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Copyrighted in Great Britain 
All Rights Reserved 

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Authors and Collaborators 


President and General Manager, The Stirling Press, Now York City 

Member, Society of Automobile Engineers 

Member, The Aeronautical Society 

Formerly Secretary, Society of Automobile Engineers 

Formerly Engineering Editor, The Automobile 


Automobile Engineer 

With Inter-State Motor Company, Muncie, Indiana 

Formerly Manager, The Ziegler Company, Chicago 


Editor, Automotive Engineering 

Formerly Managing Editor Motor Life, Editor The Commercial 1 chic! 

Author of "What Every Automobile Owner Should Know" 

Member, Society of Automobile Engineers 

Member, American Society of Mechanical Engineers 


Editor, Motor Aye. Chicago 
Formerly Managing Editor, The Light Car 
Member, Society of Automobile Engineers 
American Automobile Association 


Secretary and Educational Director, American School of Correspondence 
Formerly Instructor in Physics, The University of Chicago 
American Physical Society 


Late Lecturer, Automobile Division, Milwaukee Central Continuation School 
Editorial Representative, Commercial Car Journal and Automobile Trade Journal 
Member, Society of Automobile Engineers 
Member, Standards Committee of S. A. E. 
Formerly Technical Editor, The Light Car 

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Authors and Collaborators— Continued 


Professor of Industrial Engineering, Pennsylvania State College 
American Society of Mechanical Engineers 


Specialist In Technical Advertising 
Member, Society of Automobile Engineers 
Formerly Associate Editor, The Automobile 


Consulting Mechanical Engineer, Chicago 
American Society of Mechanical Engineers 


Superintendent Union Malleable Iron Company, East MoNnc, Illinois 


Formerly Dean and Flead, Consulting Department, American School of 

Member, American Society of Mechanical Engineers 


Associate Editor, American Technical Society 
Formerly Managing Editor of Xntionnl Builder 
Member, American Association of Engineers 


President, W. R. Howell and Company, London, England 


Associate Editor, Motor Age, Chicago 


Head, Publication Department, American Technical Society 

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Authorities Consulted 

THE editors have freely consulted the standard technical litera- 
ture of America and Europe in the preparation of these 
volumes. They desire to express their indebtedness, particu- 
larly, to the following eminent authorities, whose well-known treatises 
should be in the library of everyone interested in the Automobile and 
allied subjects. 

Grateful acknowledgment is here made also for the invaluable 
co-operation of the foremost Automobile Firms and Manufacturers 
in making these volumes thoroughly representative of the very latest 
and best practice in the design, construction, and operation of Auto- 
mobiles, Commercial Vehicles, Motorcycles, Motor Boats, etc.; also 
for the valuable drawings, data, illustrations, suggestions, criticisms, 
and other courtesies. 


Consulting Engineer 

First Vice-President, American Motor League 

Author of "Roadside Troubles" 


, Late Consulting Engineer 

Past President of the American Society of Civil Engineers 
Author of "Artificial Flight," etc. 


Member, American Society of Mechanical Engineers 

Author of "Gas-Engine Handbook," "Gas Engines and Their Troubles," "The 
Automobile Pocket-Book," etc. 


Member, American Society of Mechanical Engineers 
Engineer, General Electric Company 
Author of "Elements of Gas Engine Design" 


Author of "Horseless Vehicles, Automobiles, and Motorcycles," "Gas, Gasoline, 
and Oil Engines," "Mechanical Movements, Powers, and Devices," etc. 



Associate Member, American Institute of Electrical Engineers 
Author of "The Storage Battery : A Practical Treatise on the Construction, 
Theory, and Use of Secondary Batteries" 

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Authorities Consulted Continued 


Director, II. J. Willard Company Automobile School 
Author of "The Complete Automobile Instructor" 


Editor, The American Cyclopedia of the Automobile 

Author of "Motor Boats," "History of the Automobile," "Automobile Driving, 

Self-Taught, " "Automobile Motors and Mechanism," "Ignition Timing and 

Valve Setting." etc. 


Mechanical Engineering Department, Columbia University 
Author of "Gas Engine Design" 


Editor, Horseless Age 

Author of "The Gasoline Automobile" 


Professor of Experimental Engineering, Sibley College, Cornell University 
Author of "Internal Combustion Engines" 


Author of "Light Motor Cars and Voiturettes," "Motor Repairing for Ama- 
teurs," etc. 


Professor of Mechanical and Electrical Engineering in University College. Not- 
Author of "Gas and Petroleum Engines" 


Member, Institution of Automobile Engineers 
Author of "Motor-Car Meehanlsms and Management" 


Professor of Experimental Engineering, Sibley College, Cornell University 
Author of "Internal Combustion Engines" 



Technical Director, The New York School of Automobile Engineers 
Author of "Motor-Car Principles" 

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Authorities Consulted — Continued 


Formerly Editor, Motor Aye 

Author of "Automobile Troubles, and How to Remedy Them" 


Associate Member, Institute of Electrical Engineers 
Author of 'Electric Ignition for Motor Vehicles" 


Member, American Society of Civil Engineers 
British Association for the Advancement of Science 
Chevalier Legion d'Honneur 
Author of "Artificial and Natural Flight," etc. 


Author of "Complete Automobile," "A li C of Motoring" 


Lecturer on Manufacture and Application of Industrial Alcohol, at the Poly- 
technic Institute, London 
Author of "Industrial Alcohol," <\c. 


Consulting Engineer 

Author of "Modem fins and Oil Engines" 


Head of Department of Electrical Engineering, Columbia University 
Past President, American Institute of Electrical Engineers 

Author of "Electric Lighting," Joint Author of "Management of Electrical 


Captain and Instructor in the Prussian Aeronaut h- Corps 
Author of "Airships Past and Present" 


Associate Member, Institute of Mechanical Engineers % 
Author of "Petrol Motors and Motor Cars" 

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Authorities Consulted — Continued 


Director of Sibley College, Cornell University 

Author of "Manual of the Steam Engine," "Manual of Steam Boilers," etc. 


Motoring Editor, The London Sphere 

Author of "The Amateur Motorist" 


Major and Battalions Kommandeur in Badlschcn Fussartlllerie 
Author of "Pocket-Book of Aeronautics" 


Professor of Steam Engineering, Massachusetts Institute of Technology 
Author of "Steam Boilers" 


Author of "Operation, Care, and Repair of Automobiles" 


Author of "Motor Boats," etc. 


Editor, Work and Building World 
Author of "Motorcycle Building" 


Author of "Self-Propelled Vehicles" 


Editor, The Encyclopedia of Motoring, Motor Seics, etc. 


Author of "Ignition Devices," "Magnetos for Automobiles," etc. 


Consulting Electrical Engineer 

Associate Member, American Institute of Electrical Engineers 

Author of "Storage Battery Engineering" 

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THE period of evolution of the automobile does not 
span many years, but the evolution has been none 
the less spectacular and complete. From a creature 
of sudden caprices and uncertain behavior, it has become 
today a well-behaved thoroughbred of known habits and 
perfect reliability. The driver no longer needs to carry war 
clothes in momentary expectation of a call to the front. 
He sits in his seat, starts his motor by pressing a button 
with his hand or foot, and probably for weeks on end will 
not need to do anything more serious than feed his animal 
gasoline or oil, screw up a. few grease cups, and pump up a 
tire or two. 

C And yet, the traveling along this road of reliability and 
mechanical perfection has not been easy, and the grades 
have not been negotiated or the heights reached without 
many trials and failures. The application of the internal - 
combustion motor, the electric motor, the storage battery, 
and the steam engine to the development of the modern 
types of mechanically propelled road carriages, has been a 
far-reaching engineering problem of great difficulty. 
Xevertheless, through the aid of the best scientific and me- 
chanical minds in this and other countries, every detail 
has received the amount of attention necessary to make it 
as perfect as possible. Boad troubles, except in connection 
with tires, have become almost negligible and even the 
inexperienced driver, who knows barely enough to keep to the 
road and shift gears properly, can venture on long touring 
trips without fear of getting stranded. The refinements 
in the ignition, starting, and lighting systems have added 
greatly to the pleasure in running the car. Altogether, the 
automobile as a whole has become standardized, and unless 
some unforeseen developments are brought about, future 
changes in either the gasoline or the electric automobile 
will be merely along the line of greater refinement of the 
mechanical and electrical devices used. 

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C, Notwithstanding the high degree of reliability already 
spoken of, the cars, as they get older, will need the atten- 
tion of the repair man. This is particularly true of the 
cars two and three seasons old. A special effort, therefore, 
has been made to furnish information which will be of value 
to the men whose duty it is to revive the faltering action of 
the motor and to take care of the other internal troubles 
in the machine. 

C, Special effort has been made to emphasize the treatment 
of the Electrical Equipment of Gasoline Cars, not only be- 
cause it is in this direction that most of the improvements 
have lately taken place, but also because this department of 
automobile construction is least familiar to the repair men 
and others interested in the details of the automobile. A 
multitude of diagrams have been supplied showing the con- 
structive features and wiring circuits of the principal sys- 
tems. In addition to this instructive section, particular 
attention is called to the articles on Welding, Shop In- 
formation, and Garage Design and Equipment. 

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Table of Contents 

Oxy-Acbtylenb Welding Practice . By Robert J. Kehlt Page *11 

Introduction — Welding: Processes: Old and New Methods — Oxy-Acetylene 
Process: Advantages, Gases, Generators, Blowpipes, Oxy-Acetylene 
Flame, Welding Rod, Flux, Strength of Weld, Cutting — Electric Proc- 
esses: Methods, Spot-Welder, Arc Welder — Technique of Oxy-Acetylene 
Welding: Simple Welding Job — Operation and Care of Welding Appa- 
ratus—Connecting Apparatus — General Notes on Welding — Properties of 
Metals — Pre-Heating — Steel Welding: Welding Heavy Steel Forgings and 
Steel Castings — Cast-Iron Welding: General Considerations, Expansion 
and Contraction, Pre-Heating, Welding Rods, Flux, Preparation of Welds, 
Welding Process — Malleable-Iron Welding: Malleable Iron, Brazing 
Malleable Iron — Aluminum Welding: General Considerations, Oxidation, 
Expansion and Contraction, Welding Rod, Flux, Flame, Sheet-Aluminum 
Welding, Cast-Aluminum Welding — Copper Welding — Brass and Bronze 
— Miscellaneous Methods: Cutting — Lead Burning — Repair — Costs 

Shop Information 

By Herbert L. Connell; assisted by W. K. Gibbs Page 115 

Introduction — Bench Work: Benches— Vises — Chipping and Filing: 
Chisels, Chipping, Filing Methods (Types of Files, Manipulation, Uses 
of Files, Accurate Filing) — Rebabbitting Bearings — Bearing Scraping — 
Soldering — Fitting Piston Rings — Use of Micrometers — Lapping Cylinders 
— Drilling and Tapping — Use of Dies — Reamers — Fitting Taper Pins — 
Hand Key-Seating — Riveting — Forging — Machine Equipment: Arbor 
Presses and Gear Pullers — Grinders — Drill Presses — Power Hack Saws — 
Lathes — Milling Machines — Shapers — Planers — Tabular Data 

Building, Equipping, and Running a Public Garage . . 

By Morris A. Hall Page 197 

Preliminary Problems: Range of Business: Selling Cars as Side Line, 
Selling Accessories, Other Side Lines — Choosing Location — Size of Garage 
— Designs of Garages: Small Size Garage: Discussion of Five Typical 
Layouts — Medium Size Garage: Discussion of Four Typical Layouts — 
Large Garages: Discussion of Three Typical Layouts — Very Large 
Garages: Discussion of Typical Layouts— Finances and Building Costs: 
Income and Expense Estimates — Typical Exteriors: Building Materials, 
Ease of Erection, Architectural Appearance, Typical Exteriors, Suit- 
ability of Garage Design — Necessary Equipment: Lighting — Heating — 
Ventilation — Water Supply — Moving Cars — Fuel and Oils — Tool Equipment 

Motorcycles . 

. . By Darwin S. Hatch; Revised by Herbert L. Connell Page 269 

Introduction — Types of Motorcycles: Smith Motor Wheel, Dayton, 
Merkel, Cyclemotor, Auto-Ped, Llght-Weight Motorcycles, Developments 
in Standard Types — Analysis of Motorcycle Mechanisms: Nomenclature 
— Principles of Engine Operation: Four-Cycle, Two-Cycle — Construction 
Details: Springs and Frames, Motors, Lubrication, Starting, Brakes, 
Drive, Clutches, Gearsets, Electrical Equipment — Special Bodies and At- 
tachments — Operation and Repair: Operation Suggestions — Repair 
Suggestions: Carburetor Troubles, Valve Troubles, Inlet Manifold, Over- 
hauling, Valve Timing, Cleaning Chains, Dirty Muffler, Electrical Troubles 

Steam Automobiles . . Revised by Herbert L. Connell Page 345 

Introduction — Heat Principles — Heat Transmission: Radiation and Ab- 
sorption, Conduction. Convection, Expansion, Laws of Gases, Heat Trans- 
formation, Thermodynamics of Steam, Superheating — Mechanical Ele- 
ments of Steam Engine: General Details — Slide Valve — Superheated 
Steam and Compound Expansion — Valve Gears — Engine Types and De- 
tails: Stanley — Doble — National — Fuels and Burners: Burner Principles. 
Pilot Light, Burner Types — Automobile Boilers: Fire-Tube Types. Water- 
Tube Types, Flash Boilers, Special Types — Boiler Accessories and Regu- 
lation: Check Valves, Stanley. Doble. Ofeldt — Management and Care of 
Steam Cars: Management on Road — Firing Up — At End of Run — Engine 
Lubrication — Scale Prevention — Filling Boilers — Water Pump— Gasoline 
Pump— Engine Bearings 

Review Questions Page 413 

Index Page 419 

•For page numbers, see foot of pages. 

tFor professional standing of authors, see list of Authors and Collabo- 
rators at front of volume. 

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Welding Field. The welding process is undoubtedly one of the 
greatest contributors to the efficient and economical manufacture of 
the modern automobile. It has made possible higher standards of 
body design and may be given almost exclusive credit for the light 
weight and great strength of the present-day motor car, producing 
stronger and better working parts through the use of pressed steel 
instead of the heavy castings or riveted parts, such as axle housings, 
Fig. 1, and manifolds, tanks, bodies, etc., Fig. 2. 

In the field of automobile repair it is rapidly assuming an equally 
important place, affording a quick and inexpensive means of perma- 
nent repair to parts no longer obtainable from the supply house or 
manufacturer and permitting the building up of weak parts or the 
altering of the chassis, as may be required. This great adaptability 
of the welding unit has made it an essential part of the equipment of 
* every efficiently managed repair shop. 


Old and New Methods. The old systems — blacksmith, or forge, 
welding, and brazing — are now seldom used in automobile work. 
In fact, most blacksmiths have equipped themselves to do welding in 
the modern way, using it almost exclusively for their repair work 
because it is cheaper, simpler, more efficient, and can be used on 
materials which could not be welded by means of the old-style 
methods. The modern systems of welding include the flame and 
electric processes. Because it is almost universally used in repair 
shops, the flame process and the apparatus required in its use will 
be discussed first. Several flame-welding processes have, from time 
to time, been introduced, all utilizing oxygen in combination with 
some fuel gas, such as acetylene, hydrogen, city gas, natural gas, 
liquid gas, Blau gas, carbo-hydrogen, thermaline, etc. Many enthu- 


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Big. 1. Oxy- Acetylene Welding in Manufacture of Rear Axle Housings 

Pig. 2. Oxy-Acetylene Welding in Manufacture of Automobile Bodies 


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siastic claims of superiority have been made for each of these combi- 
nations by their advocates. 


Advantages. The easy control and intensity of the heat devel- 
oped by the oxy-acetylene flame (approximately 6300° F.) and the 
adequate supplies of carbide and dissolved acetylene which are 
maintained in every industrial center in the United States have 
proved the greater desirability, economy, and efficiency of the oxy- 
acetylene process. 

Another factor which has contributed largely to the popularity 
of the oxy-acetylene process is the comparatively inexpensive appara-* 
tus required and the low cost of its operation. Its speed, portability, 
and the ease with which its method of operation maybe learned by 
any intelligent workman make it especially well fitted to the need of 
the automobile repair shop. Very seldom is any extensive disman- 
tling of parts necessary in making an oxy-acetylene repair and, for this 
reason, it simplifies greatly the work of the repair man. 

Gases. As is generally known, two gases are used in the oxy- 
acetylene process — oxygen and acetylene. 

Oxygen. Oxygen is manufactured from air by liquefaction or 
from water by electrolysis. The former method is by far the greatest 
source of supply, furnishing practically all the oxygen used in this 
country and abroad. Oxygen made by the liquid-air process can 
contain only an impurity such as nitrogen, which cannot possibly do 
any harm. On the other hand, oxygen made by the electrolytic 
method contains some hydrogen, which will render it dangerous to 
handle if more than two per cent is present. 

Because of the very high cost of an oxygen plant and the ease 
with which an adequate supply of compressed gas may be obtained 
from manufacturers' supply, stations, it has been found impractical 
for even the largest consumers to attempt the manufacture of their 
own oxygen. 

Almost everybody is familiar with the appearance of the oxygen 
cylinder, shown at the right in Fig. 3, which plays so important a 
part in present-day manufacturing. These steel cylinders contain 
100 or 200 cubic feet of gas compressed to a pressure of 1800 pounds 
per square inch. They are furnished to the consumer without charge, 



the customer paying only for the oxygen and returning the cylinder to 

the manufacturer when the gas has been exhausted. 

Acetylene. The acetylene may be obtained in cylinders, shown at 

the left in Fig. 3, containing 100 or 300 cubic feet, or, where large 

quantities are re- 
quired, it is generated 
on the premises. 
Though frequently re- 
ferred to as com- 
pressed, the acetylene 
in cylinders is really 
not compressed, but 
is dissolved in a sol- 
vent which has the 
property of absorbing 
many times its own 
volume of acetylene as 
pressure is applied. 
This liquid in which 
the gas is dissolved in 
no way affects the flow 
of gas except when the 
acetylene is drawn off 
from the cylinder at 
too rapid a rate. Ex- 
perience has proved 
that when the gas is 
used at a rate greater 
than one-seventh the 
capacity of the cylin- 
der per hour, the 
solvent is very likely 

Fig. 3. Welding Unit for Use with Acetylene in Cylinders, 

Mounted on Emergency Truck to travel With the 

Courtesy of Oxweld Acetylene Company, Chicago, IUinoxt A , , . - 

acetylene, lowenngtne 
temperature of the flame and thus hindering the work. To overcome 
this difficulty, where it is necessary to supply gas at a greater rate, 
several cylinders may be coupled to a manifold, or header, so that the 
total capacity is at least seven times their hourly discharge. 


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Generators. By means of the acetylene generator it is possible 
to produce pure acetylene at less than half the cost of dissolved acety- 
lene, so that if any considerable work is to be done a generator 
will pay for itself within a few months or a year. In these generators 
small quantities of calcium carbide are automatically fed into a large 

Fig. 4. Low-Pressure Acetylene Generator 
Courtesy of Oxwdd Acetylene Company, Chicago, IUinoi* 

quantity of water, producing the gas at just the rate required by the 
work in hand. 

There are two recognized systems of generating acetylene — 
the low-pressure system and the pressure system. 

Lvw-Pressure Generator. This type of generator, Fig. 4, delivers 
acetylene to the blowpipe under a pressure of less than one pound. 
This system has the advantage of maintaining at all times an abso- 

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lutely constant pressure, which is an essential requirement. The 
carbide feed is controlled by the rise and fall of the gas bell, in which 
the pressure is always the same, without the use of any pressure- 
regulating device. 

Pressure Generator. The pressure generator, Fig. 5, delivers 
acetylene at a pressure of more than one pound. The carbide feed is 
controlled by the pressure in the generator. As the acetylene is 
drawn off and the pressure decreases, carbide is fed into the water; 

Fig. 5. Portable Pressure Acetylene Generator 
Court tty of Oxxcdd Acetylene Company, Chicago, Illinois 

the generation of gas increases the pressure and the feeding stops. 
In order to compensate for this pressure variation, a pressure-dia- 
phragm regulator, or reducer, is necessary so that the acetylene may 
be supplied to the blowpipe at a constant pressure. 

The low-pressure generator furnishes the most satisfactory 
service under average conditions, though where portability is essen- 
tial, pressure generators of compact construction may be obtained to 
meet this need. 

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Welding Blowpipes. There are two types of oxy-acetylene 
welding blowpipes, namely, the low-pressure, or injector type and 
the equal-pressure type. 

Fig. 6. Oxy-Aoetylene Welding Blowpipe 
Courtesy of Oxwtld Acetylene Company, Chicago, Illinois 

Injector Blowpipe. In the injector type, Fig. 6, the acetylene is 
delivered to the blowpipe at a pressure of only a few ounces. The 
oxygen at a higher pressure passes through the injector, Fig. 7, and 
expands rapidly into the mixing chamber. This rapid expansion 
and high velocity of the oxygen form a suction and draw in the acety- 
lene at a constant ratio. A slight variation in pressure of either 

Fig. 7. Section of Injector-Type Blowpipe 

the oxygen or acetylene is automatically taken care of by the injector, 
so that a neutral flame is maintained at all times. 

Pressure Blowpipe. In this blowpipe the acetylene is used at 
almost the same pressure as the oxygen. The oxygen enters the 
mixing chamber at the rear and the acetylene through a couple of 
holes at the side. 

Fig. 8. Section of Preeeure-Type Blowpipe 

In the injector blowpipe the rapid expansion into the tapered 
mixing chamber sets up a whirling action and produces an intimate 
mixture pf the oxygen and acetylene so that a ratio of 1.05 parts 
oxygen to 1.00 part acetylene is obtained, which is almost the theo- 


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retical or perfect ratio of 1 .00 to 1 .00. In the pressure blowpipe there 
is no means of obtaining such an intimate mixture of the gases in the 
mixing chamber, Fig. 8, which in most cases is not tapered, and con- 
sequently about the best ratio obtainable is 1.14 to 1.00. This larger 
amount of oxygen is, of course, wasted and, besides, tends to produce 
an oxidized weld. It is the surface oxidation, or burning, of the 
molten metal that leads some operators to believe that they are 
welding fast, while in reality they are only burning the surface and are 
not fusing the metal underneath. 

Oxy-Acetylene Flame. The oxy-acetylene flame is the hottest 
flame obtainable. Its temperature of 6300° F. is 2000 degrees above 
that of any of the other flames. This high temperature allows the 
work to be done quickly and with only a very slight loss of heat due 
to conduction and radiation. 

There are three phases of the oxy-acetylene flame, Fig* 18, 
namely, the neutral, or welding, flame; the carbonizing, or reducing, 
flame; and the oxidizing flame. Each of these has its characteristic 
appearance and it takes only a little practice to instantly recognize 
them. The appearance of these will be taken up later under "Flame 
Regulation", page 25. 

Expansion and Contraction. These natural changes of the work, 
due to the heat of the welding, are taken care of in the case of rolled or 
forged materials by proper spacing of the edges or by holding the work 
in suitable jigs and, in the case of castings, by proper pre-heating and 
cooling. The most satisfactory methods of handling this feature will 
be taken up under the instructions for welding various materials. 

Preparation of the Work. This is a very important feature and 
should receive the operator's best thought and effort. A fair amount 
of reasoning and planning on the part of the operator before he 
attempts a job will save considerable time and keep the cost of the 
welding low. The operator should figure out several ways and means 
of handling the particular task at hand, and should then select the 
best. This applies especially to castings, such as crankcases and 
cylinders, which may be welded perfectly if the operator uses good 
judgment but which will be ruined if he does not. 

Welding Rod. Thin plates may be welded by bringing the edges 
into contact and fusing them together. For heavier work, the edges 
are beveled to form a groove, and a filling material, or "welding- 


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rod", is fused into the groove. In most cases a material similar to 
the work being welded is used. The operator may build up the weld 
by means of the welding rod so that the section at the weld is greater 
than the section before welding, thus insuring a strength even greater 
than the rest of the piece. 

Flux. A suitable flux is used in cast iron, aluminum, brass, 
copper, etc., welding to dissolve any impurities and to give a film, 
or protecting coating, to the fused material to prevent oxidation. 

Both the welding rod and the flux used are extremely important 
factors in the welding and should be obtained from a reliable manu- 
facturer who supplies only materials that are tested and analyzed to 
determine their purity and suitability for the work. 

Strength of Weld. With proper equipment and suitable rods 
and fluxes, the strength of the weld will depend mainly upon the skill 

Fig. 9. Oxy-Acetylene Cutting Blowpipe 
Courtesy of Oxweld Acetylene Company, Chicago, Illinois 

and care of the operator. An operator who has had considerable 
experience and who is careful with his work should be able to obtain 
as high as 95 per cent the strength of the original material, although 85 
per cent may be taken as a safe lower limit for the average good welder. 

Working and Hammering. If the weld is hammered when at 
the proper temperature, its strength will be increased, in the case of 
welds in steel, by making the grain of the material finer. 

Experience of Operator. Poor work due to carelessness or 
inexperience of the operator, poorly designed and cheaply constructed 
apparatus that is not capable of handling the work, may be held 
responsible for such failures as may occur in the oxy-acetylene process. 

The handling of the process is not difficult and, therefore, some 
operators undertake difficult jobs before they are sufficiently capable 
or experienced. When such a job fails, it is but natural that both the 


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customer and the operator should blame the process rather than the 
way in which the work was handled. Time may be very profitably 
spent in practice on scrap material before undertaking work on mate- 
rials with which the operator is unfamiliar. By thus laying the 
foundation for a satisfactory result, the operator may quickly develop 

Fi«. 10. Electric Spot-Welding Machine 
Courtesy of Thomson Spot Welder Company, Cincinnati, Ohio 

his skill to the point which will bring him the confidence and patron- 
age of a constantly increasing number of customers. 

Oxy-Acetylene Cutting. Cutting by the oxy-acetylene process 
is done by means of a separate blowpipe, Fig. 9, quite different in 
construction from that used for welding. A more detailed description 
of the cutting process is given on page 77. 

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Methods. For a number of years electric welding was used as a 
laboratory experiment, but recently the process has been more fully 
developed. Two distinct methods are utilized: one, the electric- 
resistance welder, or spot-welder, Fig. 10; and the other, the electric- 
arc welding machine, Fig. 1 1 . 

Spot-Welder. The electric-resistance welding process provides 
for the passage of a heavy current through the joint between the 
pieces to be welded, allowing the resistance of the bad contact to heat 
them locally until they are soft enough to stick together; squeezing 

Fig. 11. Portable Arc- Welding Outfit 
Courtesy of C & C Electric and Manufacturing Company, Garwood, New Jersey 

the pieces while soft will then cause them to adhere. This process is 
used mostly in making light automobile parts, such as mud guards, 
bonnets, etc., rather than for repair. It is also used to some extent 
instead of small rivets in light sheet-metal work and for spotting, or 
tacking, small parts together preparatory to welding them with the 
oxy-acetylene flame. 

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Arc Welder. In order to do welding with the electric arc, after 
suitable equipment has been provided, it is necessary to first connect 
the work to the positive side of the power-supply circuit and the 
welding electrode to the negative side of the circuit by means of wires 
or cables, with the regulating devices in circuit to control the amouut 
of current flowing. The negative electrode is then placed lightly in 
contact with the work and quickly withdrawn to make the circuit 

Fig. 12. Operator Using Metallic Electrode 
Courtesy of C & C Electric and Manufacturing Company, Gartoood, New Jertey 

and draw the arc, thus providing the high temperature required for 

Electric-arc welding usually consists in using the heat of the arc 
to fuse, or melt, the filling material into the place to be filled, although 
the article worked upon may be melted down sufficiently to fill the 
space if it is large enough at the point to be welded. 

Two methods, or processes, using the arc for welding, are in 
commercial use, these being the metallic and the graphite, or carbon, 

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Metallic Electrode. The metallic welding process consists in using 
a piece of wire of the proper kind as the negative electrode of the arc 
and fusing it into place, drop by drop, Fig. 12. 

Graphite Electrode. The graphite process consists in using a piece 
of graphite, or carbon, as the negative electrode and fusing a piece of 
metal into place by the heat of the arc. 

Apparatus. It is possible, though not practical, to do electric- 
arc welding, having nothing but a source of primary current, and some 



Kjui n h }\h rv — 




Fig. 13. Wiring Diagram for C & C Welding System 

means for regulating the amount of current flowing, but the use of 
resistance only as a means of regulating the amount of current flow is so 
wasteful that other apparatus must be used for the sake of economy. 
It is well known among electrical men that a motor-generator set 
gives the best regulation of voltage, therefore, the leading arc-welding 
outfits in use today consist of a motor-generator set with suitable 
rheostats, resistances, circuit-breakers, fuses, indicating instruments, 
and switches for controlling the motor-generator and welding cir- 
cuits, Fig. 13. 


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From the foregoing description, it will be surmised that an electric- 
arc welding equipment will be too expensive in initial cost for the 
average auto repair shop. However, it finds a useful field in the 
welding of very heavy work where there is sufficient volume of it to 
justify the investment. 


Apparatus Required. The material in the following paragraphs 
must not be considered as instructions for welding but merely as a 
brief discussion of the various steps in making a simple weld. Com- 
plete instructions for connecting and operating the equipment are 
given in detail later. In general, the following equipment is needed 
for every welding job, no matter how small: 

(a) A welding blowpipe 

(b) A supply of oxygen 

(c) An oxygen regulator 

(d) A supply of acetylene 

(e) An acetylene regulator 

(f) Hose to connect blowpipe to oxygen and acetylene supplies 
Preparing the Metal. First, the edges of the two pieces of metal 

to be welded are chamfered or beveled, so that when they are placed 
together the two beveled edges form a V, the width of the V being 
about equal to the thickness of the metal. 

Next, the two pieces are placed together on a flat surface of fire 
brick, or other nonconductor of heat, so that the edges just touch at 
the bottom of the groove. This gives the line of the weld. The two 
pieces are then ready to be welded as soon as the apparatus is con- 

Connecting the Apparatus. To connect the apparatus, the 
following steps should be taken: 

(1) The oxygen regulator is connected to the oxygen cylinder. 

(2) The acetylene regulator is connected to the acetylene cylinder. 

(3) The one hose is connected to the oxygen regulator and to the 


(4) The other hose is connected to the acetylene regulator and to the 



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(5) A welding head is selected and attached to the blowpipe. 

(6) The oxygen and acetylene are turned on and the blowpipe is 


Welding. The operator is now ready to weld. He takes the 

lighted blowpipe in his right hand, Fig. 14, and plays the flame upon 

the beveled edges of the two pieces of metal to be welded. The 

intense heat of the flame melts the edges and they flow together. As 

Fig. 14. Simple Job of Welding 

the edges flow together, the operator melts in new metal from a rod 
which he holds in his left hand, so that the entire goove is filled up, 
producing a perfect union or weld. 

When the entire groove has been filled in this manner, the 
operator turns out the blowpipe, and allows the metal to cool. 

The foregoing is a brief outline of the steps taken by an operator 
in performing a simple operation of welding two small pieces of steel. 

We will now take up these different steps and will give more 
specific and detailed descriptions of the welding apparatus and com- 
plete instructions in its operation and use. 


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Necessity for Care. It is proper that in the operation of the 
welding apparatus we should lay stress upon the importance of careful 
and orderly methods in the handling of such apparatus. It should 
be borne in mind that the regulators and gages are sensitive measuring 
devices, that in the blowpipe the orifices are carefully designed and 
accurately machined to permit the passage of a definite quantity of 
gas and, therefore, that rough usage and abuse will certainly decrease 
their efficiency. It is not necessary in this place to give detailed 
instructions for the operation and care of the various makes of appara- 
tus, because these are invariably furnished by the manufacturers with 
their equipment. 

Because of the fact that dissolved acetylene is most generally 
used in garages and small job shops, we will confine our explanations 
to the use of apparatus with cylinder equipment. Owing to the 
greater simplicity of handling, however, the operator will have no 
difficulty in making use of generated acetylene when the opportunity 

Necessary Welding Apparatus. A complete welding station, 
Fig. 15, for use with acetylene dissolved in cylinders, consists of the 
following apparatus: 

Welding blowpipe G with set of welding heads 

Oxygen welding regulator C with two gages 

Acetylene regulator D with one or two gages 

Adapter L for acetylene cylinder 

Two lengths high-pressure hose E and F 

Darkened spectacles, wrenches, hose clamps, etc. 

Welding Blowpipe. The two types of welding blowpipes were 
described on pages 7 and 8, and need no further explanation as to 
the principles of operation. They are furnished by the manufacturers 
in various lengths to take care of various classes of work, from short 
light-weight blowpipes less than a foot long for light sheet-metal work 
up to blowpipes several feet long, which allow the operator to stay 
away from the intense heat as far as possible when working on heavy 

Welding Heads and Tips. About ten sizes of welding heads, 
or tips, are supplied for use on different thicknesses of metal and vari- 
ous classes of work, each giving its own special size flame. The 


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oxygen consumption of the various size heads ranges from about 4 to 
70 cubic feet per hour. In some makes the heads are made of one 

Fig. 15. Complete Welding Station 

piece, while in others they consist of a brass or bronze body and a 

copper tip, which can be easily and cheaply replaced when necessary. 

Working Pressures. The necessary pressures of the gas that are 

required by the different size welding heads are given by the manufac- 


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turers, and it is very important that the operator use only the pres- 
sures recommended if he wishes to get the best economy and the 
strongest weld possible. Some operators believe that by increasing 
the pressure above that specified by the maker of the apparatus that 
they are able to do the work more quickly and easily. This idea is 
wrong, because when the pressure is increased, the larger volumes of 
oxygen and acetylene cannot mix as well, so that oxide forms in the 
weld and has to be removed. This takes more time and is very likely 
to leave a slightly oxidized and weak weld. 

If the welding head being used is not large enough, use a larger 
size; never try to increase the ability of the smaller head by increasing 

the pressure. 

It is equally bad to use a pres- 
sure that is too low. If this is done, 
continual back-firing will result. 

Care of Blowpipe. If the blow- 
pipe is handled properly there will 
be very little deterioration. It 
should only be necessary to clean 
the replaceable and working parts 
and occasionally ream out the tips. 
The tips should never be 
reamed out with any instrument 
Fi«. 16. cleaning Blowpipe by Means of other than a copper or brass wire 

Oxygen under Pressure havJng ft ]()ng ^^ ^^ ^^jj 

be taken that the orifices of the tips are not enlarged by reaming. 
If they become enlarged, they may be closed slightly by placing a 
conical swag over the end and tapping lightly with a hammer. The 
end of the tip should then be dressed off square by means of an 
extra fine file, and the orifice trued round by reaming with a twist 
drill of the proper size. V 

The blowpipe may be cleaned by removing both the acetylene 
and the oxygen hose and connecting the tip to the oxygen hose. 
Fig. 16, and turning on the oxygen to a pressure of about 20 pounds 
per square inch, having the acetylene needle valve open and the oxygen 
needle valve closed, so as to drive any obstructions through the larger 
acetylene passages of the blowpipe. Then close the acetylene valve 
and open the oxygen valve to clean out the oxygen passages. 


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Regulators. There are various types of regulators on the 
market today, but the most successful ones are very similar in design 
and construction. The principal parts of a constant-pressure regu- 
lator, Fig. 17, consist of the body proper, regulator valve, diaphragm, 
pressure-adjusting spring, safety-relief valve, and gages. 

The diaphragm may be either special reinforced rubber sheeting 
or phosphor bronze. The former is preferred, because it is less likely 
to crack, or split, is more readily replaced, and gives more sensitive 
regulation because of its finer elastic properties. 

Fig. 17. Section of Pressure Regulator 
Courtesy of Oxweld Acetylene Company, Chicago, Illinou 

Operation of the Regulator. Gas passes from the cylinder valve 
through the passageway to the regulator valve. The pressure over- 
comes the tension of the inner spring and moves the sleeve-piece 
toward the back of the regulator, opening the valve. This allows gas 
to pass into the diaphragm chamber and out of the regulator by way 
of the hose connection. As the pressure in the diaphragm chamber 
increases, the tension of the pressure-adjusting spring is overcome, 
the diaphragm deflects, the sleeve-piece moves forward, and the valve 


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closes partly or all the way. Then, as gas passes out of the regulator 
and the pressure in the diaphragm chamber decreases, the tension 
of the pressure-adjusting spring and the pressure of the gas entering 
the regulator move the sleeve-piece backward, admitting more oxygen 
to the regulator. The pressure in the diaphragm chamber builds up 
as before, the diaphragm deflects, the sleeve-piece moves outward, 
and the valve closes. 

Oxygen Welding Regulator. This is an automatic regulator 
which is especially designed for welding operations. It is connected 
to the oxygen cylinder and is designed to deliver oxygen to the blow- 
pipe at any uniform pressure at which the regulator is set. To do 
successful welding, the oxygen regulator must be as nearly perfect as 
it is possible to construct it. This device is required to reduce a 
pressure which may be as high as 1800 pounds per square inch in 
the cylinder and which is constantly varying, down to a pressure 
from 10 to 30 pounds per square inch ; at the same time the regulator 
must keep the lower pressure constant. 

Oxygen regulators are usually equipped with two gages. The 
high-pressure gage shows the pressure of the gas in the cylinder and 
may be used to determine the amount of oxygen in the cylinder (see 
under Measuring Oxygen, page 99). The low-pressure gage shows 
the operating pressure at which the oxygen is being supplied to the 

Acetylene Regulator. The acetylene regulator is used with 
acetylene sjupplied in cylinders. It is connected to the acetylene 
cylinder adapter, and this to the acetylene cylinder. The acetylene 
regulator is designed to deliver acetylene at a uniform pressure, as 
needed by the blowpipe. 

Acetylene regulators are usually equipped with a large gage that 
shows the pressure in the cylinder, but which cannot be used to 
accurately determine the contents of the cylinder (see Measuring 
Acetylene, page 102). A small gage is not necessary with the low- 
pressure, or injector, blowpipe, because the acetylene pressure required 
by this type of blowpipe is very low — only a few ounces. With the 
pressure blowpipe, however, a small gage is necessary, because it is 
important to know that the acetylene pressure, which ranges from 2 
to 13 pounds per square inch, is supplied to the blowpipe at the 
required pressure for the tip used. 


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Care of Regulators. Never drop or jar a regulator. Do not use oil, 
grease, or any organic material for lubrication in connection with regu- 
lator. If it becomes necessary to lubricate the pressure-adjusting 
screw, or to repack a needle valve, make use of a little glycerine — 
nothing else. 

Do not allow dust to enter the regulator. Always insert the 
dust plug when the regulator is not in use. These are supplied with 
most regulators and are intended to keep dust out of the regulator 
when it is not in use and to protect the union nipple at the back. 

Do not change the regulator from one cylinder to another without 
releasing the pressure-adjusting screw. The diaphragm is liable to be 
ruptured if there is tension on it when the sudden rush of gaS takes 
place as the cylinder valve is opened. 

Do not attempt to repair, adjust, or change the internal mechan- 
ism of the regulator, other than replacing the diaphragm and resurfac- 
ing or replacing the valve seat. Send it to the manufacturer for 

Do not replace diaphragms or valve seats with any material 
other than that supplied by the manufacturer for this purpose. 

Hose. The best hose that it is possible to obtain should be used, 
because it is really the most economical in the end, although it might 
cost more at the beginning. A good grade of two-ply hose will be 
found to be flexible, light weight, easy to handle, and, at the same 
time, will not kink easily nor be permanently flattened if heavy 
objects happen to accidentally fall on it. In selecting a hose, the 
welder should see that he gets a hose that has a finished inside surface, 
so that small particles of rubber and dust will not flake off and be 
blown into and clog the blowpipe or welding head. 

It is best to use different colored hose for the oxygen than for 
the acetylene to prevent errors in connecting and to avoid any pos- 
sible danger from interchanging. 

Care of Hose. Both the acetylene and the oxygen hose should be 
blown out occasionally so that dirt and dust will not be carried into 
the blowpipe. This can be done by removing the hose from the 
blowpipe, connecting each in turn to the oxygen regulator, and 
allowing oxygen of about 20 pounds per square inch to blow through 
it. Examine the hose, from time to time, for leaks by immersing in 
water when under pressure. 


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Preliminary Operations. The following directions are given 
as a starting point for beginners in the operation of welding equipment. 
The letters given refer to the labeled parts in Fig. 15, page 17. 

1. First open the oxygen cylinder valve B for a moment to 
blow out any dirt or dust which may have collected in the valve, so 
that it cannot enter the oxygen regulator when it is attached to the 

2. Remove the regulator dust plug and. attach the oxygen 
regulator C to the oxygen cylinder A. 

3. Connect the oxygen hose E to the oxygen regulator and to 
the oxygen hose connection on the blowpipe G. The hose connec- 
tions are usually readily distinguished by markings on the needle 

4. Release the pressure-adjusting screw on the oxygen regulator 
by turning to the left until it is perfectly free. 

Do not open the valve on the oxygen cylinder until positive that 
the adjusting screw on the regulator is fully released. The diaphragm 
may be ruptured and the regulator put out of commission. 

5. Slowly open the oxygen cylinder valve B as far as it will go. 
Not part way. 

Do not leave the valve on the oxygen cylinder only part way open. 
This valve seats when fully opened or closed, but is likely to leak when 
open only part way. 

Do not handle the regulator with greasy hands nor allow any oil, 
soap, or organic matter to come in contact with any part of the regu- 
lator or cylinder valve. Oxygen under high pressure coming in con- 
tact with these substances is dangerous. 

6. Wipe out the acetylene cylinder valve to remove any dirt 
or dust which may have collected in the valve, so that it cannot enter 
the acetylene regulator when it is attached to the cylinder. 

7. Attach the adapter L to the acetylene cylinder K. 

8. Remove the regulator dust plug and attach the acetylene 
regulator D to the adapter. 

9. Connect the acetylene hose F to the acetylene regulator and 
to the acetylene hose connection on the blowpipe G. 

10. Release the pressure-adjusting screw on the acetylene 
regulator by turning to the left until it is perfectly free. 


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11. Open the acetylene cylinder valve about three full turns by 
means of the wrench J. 

12. Select the welding head of the size suitable for the work in 
hand. Screw the welding head down firmly, but not too tightly, into 
the head of the blowpipe with the wrench provided for that purpose. 

Starting the Work 

How to Light the Blowpipe. 1. Take the blowpipe in hand and 
open the oxygen needle valve fully. 

2. Turn the oxygen pressure-adjusting screw to 'the right until 
the required pressure for the welding head being used shows on the 
low-pressure gage. See the maker's chart for the correct pressure. 

3. Close the oxygen needle valve. 

4. Open the acetylene needle valve fully. 

5. Turn the acetylene pressure-adjusting screw to the right until 
a good jet of acetylene issues from the welding-head orifice. In the 
case of pressure blowpipes, turn the screw until the required pressure 
for the welding head being used shows on the low-pressure gage. (See 
the maker's chart for the correct pressures). 

6. Open the oxygen needle Valve slightly and light the blowpipe 
by means of the pyro-lighter that is usually furnished. 

7. Open the oxygen needle valve fully. 

Note: A back-fire might occur when turning on the oxygen if there is not 
enough acetylene being supplied. If this occurs, increase the acetylene supply 
by turning the acetylene pressure-adjusting screw farther to the right. 

8. Adjust the acetylene pressure-adjusting screw to give a 
slight excess of acetylene to the flame. 

9. Adjust the acetylene needle valve to give a neutral flame 
(see under Flame Regulation, page 25). 

How to Shut Off the Blowpipe. In the case of the injector type 
blowpipe, first close the acetylene needle valve, and then the oxygen 
needle valve. 

In the case of pressure blowpipes, first close the oxygen needle 
valve, and then the acetylene needle valve. 

When laying aside the blowpipe for a short time, the pressure- 
adjusting screws on both regulators should be released by turning to 
the left until free. 

When work is suspended for any considerable time, the valves 
on both cylinders should be closed. 


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Never light the bknvpipe unless some oxygen is passing through it. 
If the blowpipe is lighted, or burned, with only acetylene passing 
through it, there will be a deposit of carbon made in the tip, which will 
in time clog the orifice and interfere with the perfect operation of 
the blowpipe. 

Back-Firing. If the flame is not properly adjusted, or the tip 
becomes clogged, the blowpipe may back-fire. When this occurs, 
first close the acetylene needle valve quickly, then open it again fully 
and relight the blowpipe. If the back-fire continues, close both the 
acetylene and oxygen needle valves. Then relight the blowpipe and 
proceed in the usual manner. 

If the blowpipe becomes overheated, it may back-fire. When 
this occurs, it may be cooled by plunging it into a bucket of water. 
Be sure that the acetylene has been shut off and a small quantity 
of oxygen is flowing through the blowpipe to prevent water backing 
into the tip and causing further back-firing when the blowpipe is 

Oxy-Acetylene Blowpipe Flame 

Character of Flame. The oxy-acetylene flame consists of two 
parts — an inner cone, which is incandescent; and an outer envelope, 
or nonluminous flame, which is sometimes called the secondary flame. 

The temperature of the oxy-acetylene flame, taken at the extrem- 
ity of the inner cone, is very much higher than that of all other flames. 
It is calculated to be approximately 6300° F. One of the main reasons 
for the superiority of the oxy-acetylene flame over all other welding 
lies in the fact that this high temperature is concentrated at the point 
of inner cone. 

The character of the oxy-acetylene flame depends upon the 
proportion of oxygen and acetylene contained in the mixture and 
the thoroughness of the mixture as it issues from the tip of the blow- 
pipe. Varying proportions of the gases produce three characteristic 
types of flame, Fig. 18, called, respectively, reducing, or carbonizing, 
flame; neutral, or welding, flame; and oxidizing flame. Each type has 
its characteristic appearance, and it takes only a little practice to 
instantly recognize each. The welder should at all times observe 
carefully the type of flame produced and promptly correct any 


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Neutral, or Welding, Flame. A neutral flame is produced yhen 
acetylene and oxygen burn in the proper proportion, theoretically 
1.00 volume of oxygen to 1.00 volume of acetylene. The appearance 
of this flame is characteristic, Fig. 18 b. It is made up of a distinct 
and clearly defined incandescent cone, or jet, of bluish hue, surrounded 
by a faint secondary flame, or envelope, purplish yellow in color and 
of a bushy appearance. 

The incandescent cone may be from ^ to f inch in length and is 
usually rounded or tapered at the end. The maximum temperature 
of the oxy-acetylene flame is ^ to A inch beyond the extremity of 
this cone. 

Fig. 18. Oxy-Acetylene Flame. Top v 

Bottom, Oxidizing Flame 

The middle illustration in Fig. 18 shows roughly the character- 
istic appearance and formation of the neutral, or welding, flame. 
This flame is the one most extensively used, and no welder is proficient 
until he is thoroughly familiar with its appearance and distinguishing 
characteristics and is able to maintain this flame under working 

Flame Regulation. The neutral flame is obtained by starting 
with a flame having a slight excess of acetylene and gradually cutting 
down the acetylene supply by means of the blowpipe needle valve. 
As this is done, the streaky appearance of the inner cone will 


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gradually diminish. The flame is neutral when the streakiness just 

Carbonizing, or Reducing, Flame. The reducing, or carbonizing, 
flame is produced when there is an excess of acetylene in the flame. 
This flame is of an abnormal volume, dirty yellow in color, of uniform 
consistency, and has a streaky appearance. By gradually decreasing 
the acetylene supply at the needle valve, the size of the flame is 
decreased, and gradually a white cone of great luminosity appears at 
the blowpipe tip. The extent of the reducing, or carbonizing, action 
of the flame is judged practically by the size and definition of the 
luminous cone. When this cone becomes more clearly defined and 
takes the form and color of a bluish white incandescent cone, or pencil, 
the streakiness is further diminished, and the flame approaches the 
neutral stage. The upper illustration in Fig. 18 shows a reducing, or 
carbonizing, flame that has a fair but not large excess of acetylene. 
The temperature of the reducing flame is considerably lower than that 
of the neutral flame. 

Use of Reducing Flame. A slight excess of acetylene is used in 
the welding of brasses, bronzes, aluminum, and certain alloy steels 
to guard against the burning out of easily oxidized elements. It has 
also been used in the case of certain mild steels to increase the carbon 
content to secure greater hardness. In this connection It must be 
remembered that increase in hardness is usually accompanied by 
decrease in strength, so that in general welding an excess of acetylene 
should not be used. 

Oxidizing Flame. An oxidizing flame is produced when there is 
an excess of oxygen in the flame. The effect of too much oxygen is to 
diminish the size of the flame, blunt or blurr the inner cone, and pro- 
duce a weak, streaky, or scattering flame. In some blowpipes, the 
inner cone is not only diminished in size but is slightly bulged at its 
extremity as compared with the neutral flame, which is shown in 
the middle of Fig. 18. The lower illustration in Fig. 18 shows the 
oxidizing flame. 

Caution Against Oxidizing Flame. An oxidizing flame should be 
carefully guarded against or it will become a source of trouble. An 
excess of oxygen will burn the metal, causing weak welds, and in the 
case of cast iron it will produce a hard weld that will be difficult to 


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Manipulation of Blowpipe and Welding Rod 
Position of Hose. Occasionally the hose is thrown over the 
operator's shoulder. In this case the weight of the blowpipe is sus- 
pended and held by the hose so that it is only necessary to impart the 
peculiar welding motion to the 
blowpipe, which can usually be 
done by the fingers. However, this 
method is not generally recom- 
mended, as it seriously hinders the 
free movement of the welding 
flame. It should be used only as 
a relief when the work is of long 
duration and the operator's wrist 
and forearm become tired. 

Position of Blowpipe. The 
operator, having lighted the blow- 
pipe and properly adjusted the 
flame, is now ready to begin weld- 
ing. Grasp the blowpipe firmly 

in the hand, as shown in Fig. 19. ««■ 19 - ^Jjjg ggjji? Holdin * 
The blowpipe is so designed that it 

balances properly when grasped at this point. It is not good practice 
to hold the blowpipe in the fingers, because it is not possible to 

Not Be Inclin< 

wpipe Should Fig. 21. Blowpipe Should Fig. 22. Blowpipe Should 

ted Too Much Not Be Held Too Vertical Not Travel Backwards 

manipulate the flame with as great regularity and control, nor will 
it be possible to do as heavy work without tiring. 

Inclination of Blowpipe. The head of the blowpipe should be 
inclined at an angle of about 60 degrees to the plane of the weld. 


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The inclination of the head should not be too great, Fig. 20, because 
the molten metal will be blown ahead of the welding zone and will 
adhere to the comparatively cold sides of the weld. On the other 
hand, the welding head should not be inclined too near the vertical, 
Fig. 21, or the secondary flame will not be utilized to its full value for 
pre-heating the metal ahead of the actual welding. 

In ordinary welding practice it is best that the top of the blow- 
pipe be so inclined and so directed that the maximum amount of pre- 
heating is obtained without blowing the molten metal ahead. 

Travel of Blowpipe. The travel of the blowpipe should be away 
from the welder and not toward him, Fig. 22, as the work can be 
observed more closely and done more easily and quickly. 

Movement of Blowpipe, In making a weld a simultaneous fusion 
of the edges of the parts to be joined and the welding rod is necessary. 
If this does not occur, a true weld is not produced. 

Fig. 23. Circular Motion of Blowpipe for Fig. 24. Oscillating Motion of Blowpipe 

Welding Light Sections for Welding Heavy Sections 

In the case of parts which have been chamfered out and which 
require the use of filling material, a peculiar motion must be imparted 
to the blowpipe, which will take in both edges of the weld and the 
welding rod at practically the same time. 

In comparatively light work a motion is imparted to the blowpipe 
which will cause the incandescent cone to describe a series of over- 
lapping circles, as shown in Fig. 23. This overlapping extends in the 
direction of the welding. This motion must be constant and regular 
in its advance so that the finished weld will have a good appearance. 
The speed of progress should be such that complete fusion of the three 
members referred to is secured. The width of this motion is depend- 
ent upon the size of the material being welded and varies accordingly 
with the nature of the work. It does not take much experience to 
establish the proper size motion and the proper rate o£ advance for 
the various sizes and kinds of metals. 


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In very heavy work, if the above system were used, a great deal 
of the motion would be superfluous. Consequently, a movement 
in which the cone of the flame will describe semi-circles should be used, 
as shown in Fig. 24. This confines the welding zone and concentrates 
the heat. While the progress is not so fast, it is more thorough than 
the other system for this class of work. 

Importance of Movement. To the average beginner the regular 
control from these motions is difficult. It requires considerable 
practice and experience to become skilled in this, but it is the regu- 
larity of these motions that produces the characteristic rippled surface 
of good welding. The progress of a welder and the quality of his 
work can be determined to some extent by the skill with which he 
produces this effect. 

Position of Welding Rod. 
After the beginner has mastered the 
peculiar motions of the blowpipe, 
his next step will be to properly 
introduce the welding rod into the 
weld in such a manner that the 
regular advance of the blowpipe 
will not be hindered or retarded. 

The Welding rod, Or Wire, ^ 26 Correct Method of Holding 

should be held and inclined, as weidingRod 

shown in Fig. 25. In this position a sufficient quantity of material 
may be added at the right time. If the welding rod were held in a 
vertical or horizontal position, the welder would be liable to add an 
excess of metal, part of which would not be properly fused. 

When to Add Welding Rod. Great care must be taken in adding 
this metal that the edges of the weld are in their proper state of fusion 
to receive it. If the metal is not hot enough, the added material will 
simply adhere to the sides, resulting in adhesion only, not a true weld. 
It is, therefore, necessary to produce equal fusion at the edges of the 
weld with that of the welding rod by the correct motion of the 

How to Add Welding Rod. When the proper time arrives to add 
the filling material, the welding rod is lowered into the weld until it is in 
contact with the molten metal of the edges. When in this position the 
flame of the blowpipe is directed upon it, and thus fusion is produced. 

39 Digitized by 



In welds of unusual depth the end of the rod is immersed in the 
molten metal and the blowpipe flame is played around it. The 
material is thus protected from the air and the gases of the blowpipe. 
The heat of fusion in this case is supplied mostly from the molten 
metal which surrounds the rod. 

Faults to Be Avoided. The usual faults of the average beginner 
are: first, failure to introduce the welding rod into the welding zone 

at the proper time; second, to hold 
the rod at the wrong angle; and 
third, to fuse either too little or 
too much of the rod. The filling 
material when melted should never 
be allowed to fall into the weld in 
drops, or globules, Fig. 26. 

Building Up the Weld. In 

welding it is customary to build up 

the welded portion in excess of the 

Fig. 26. welding Rod should Not Be thickness of the original section. 

Allowed to Fall into the Weld in Drops & 

There are several reasons for doing 
this. First, the weld is reinforced and the strength is accordingly 
increased. Second, in case it is desired to finish the surface there is 
sufficient stock to allow machining. Third, in some cases small pin- 
holes or blowholes may be found just under the surface of a weld, 
which do not extend to any depth in the weld and may be removed 
by filing or machining. 


The above are basic principles involved in producing all good 
oxy-acetylene welds. There are many detailed operations which 
must be learned by practice for the successful handling of the 
different metals, but by keeping in mind these basic principles and 
by applying them properly, the more difficult operations can be readily 

Haste Fatal to Good Welding. It is a fundamental rule for 
successful welding that the operator must give his undivided attention 
to the work in hand. Do not try to hurry over or slight any step of the 
work. You cannot weld faster than the metal will melt and fuse 


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Burning a Hole in the Metal. Occasionally an operator becomes 
so interested in some minor detail of his work that he allows the flame 
to burn through the metal and form 
a hole. 

How to Weld Up a Hole. It is 
a difficult operation for a beginner 
to fill these holes. His first at- 
tempts usually result in enlarging 
the holes instead of closing them. 
The proper way to take care of 
this is to incline the blowpipe so 
that the flame is almost parallel to 

the Surface Of the Work, Fig. 27. Fig. 27. Method of Filling in a Deep 

„ T . X , .tit • • x i • v.. Hole— Start at the Upper Edge 

With the blowpipe in this position, 

play the flame upon the upper edge of the hole until the sides become 
plastic, taking care that the edges do not become entirely fused. 
When the edge is in the proper condition, the welding rod is interposed 
and a small amount of metal is added to the top edge of the hole. 
This operation is repeated until the hole is filled in. As the work pro- 
gresses, the blowpipe is gradually raised until it resumes its normal 

Overhead and Vertical Welding. In welding overhead, Fig. 28, 
or vertically, Fig. 29, the same 
procedure is followed as in filling a 
hole. The metal should not be 
allowed to reach the state of fusion 
that is secured in ordinary weld- 
ing. It should be hot enough to 
assimilate the welding rod, but not 
so fluid that it will flow out of the 
weld. In overhead welding care 
should be taken that oxidation 
does not occur, because the 
molten oxide will flow from the 

weld and seriously inconvenience Fig. 28. Overhead welding 

the operator. 

Beginning a Long Weld. In beginning a long weld pains should 
be taken to see that it is started properly, and at this point of the 


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work time should not be spared. When the weld is properly started 
the speed may be increased. As the weld advances the speed becomes 

Fig. 29. Vertical Welding 

greater, because the material becomes heated up and the blowpipe 
action is faster. 

Defects in Welds. There are a number of sources of defects 
in welds, and the average beginner usually encounters all of them 
before he becomes a skilled welder. 

Improper Flame Adjustment. If the flame is not properly 
adjusted the weld will be inferior. The commonest fault is the 
presence of too much oxygen in the welding flame. Unless the 
operator takes a great deal of care in removing the oxidized particles, 
they will be incorporated in the weld, Fig. 30. The oxide, of course, 

Fig. 30. Oxidised Weld Fig. 31. Failure to Completely Penetrate to the 

Bottom of the Weld 

greatly decreases the strength and greatly affects the other mechanical 
properties of the weld. 


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Failure to Penetrate. A fault, not only of the beginner but also of 
the skilled operator, is failure to penetrate to the bottom of the weld, 
Fig. 31, and is the cause of a great many defective welds. In his 
desire to complete a weld as soon as possible, the operator very often 
hastens over the most important 
part of the work, which is to 
secure the absolute fusion of the 
edges at the bottom of the weld. 

Failure to do this not. only 

* i i uxe weia 

reduces the section of the metal 

at the weld, but also gives a line of weakness in case the welded 

pieces are submitted to bending or transverse strains. 

Adhesion of Added Metal. When molten metal from the welding 
rod is added to the edges of the weld which are not in fusion, a weld 
is not secured. The added metal merely adheres to the cooler metal, 
Fig. 32, and perfect fusion is not secured. Adhesion may be caused 
by improperly chamfering the pieces to be welded, by improper incli- 
nation of the blowpipe, by improper use of the welding rod, or by 
faulty regulation and manipulation of the welding flame. 

The tendency of beginners is to not prepare the pieces properly 
for welding. Usually the chamfering, or grooving, is either not deep 
enough, that is, does not extend entirely through the section to be 
welded, or it is not wide enough. In welding pieces improperly 
prepared the tendency of adhesion is great. 

The most common fault is the addition of the welding rod to the 
edges of the weld before they are in fusion. The adhesion in this case 
is applied to both edges. Sometimes one edge of the weld is in fusion, 
but the other is not. In this case adhesion is applied to only one side, 

Fig. 33. Weld Not Properly Reinforced Fig. 34. Weld Properly Reinforoed 

but with the effect that the strength of the weld is lessened the same 
as when adhesion occurs on both sides. 

In some cases the edges of the metal are brought to a state of 
fusion too soon, so that oxide has an opportunity to form on the edges 


* ~ Digitized by 



of the weld. Then, when the welding rod is added, adhesion occurs 
with a film of oxide separating the edges and the added material. 

Often an operator will concentrate the flame upon the welding 
rod and the edges of the weld. Then, as the blowpipe is played 
around the welding rod, some of the molten metal is forced ahead. 
The metal ahead is not in the proper state of fusion and consequently 
adhesion results. 

Irmifficimt Reinforcing. It is not uncommon to see welds 
produced that do not contain enough metal, Fig. 33. All welds 
should be reinforced with additional metal as in Fig. 34. In case a 
smooth finish is desired this excess metal car be removed by grinding 
or machining. Too great an excess of metal n ust not be added be- 
cause this takes extra time and the gases are wasted. 


Before the beginner takes up the actual welding of metals, it is 
necessary that he study their properties, peculiarities, and behavior 
under the action of the welding flame. Some of the physical proper- 
ties of the more common metals are given in Table I. 

Melting Point. The first property that the welder should 
consider is the melting point or temperature at which the metal will 
fuse or become fluid. The average welder is usually fairly familiar 
with the difference in melting points of lead or zinc, and iron or steel ; 
but he is usually not familiar with the difference between the melting 
points of brass, bronze, copper, white cast iron, gray cast iron, etc. 
This knowledge is especially important if it becomes necessary to weld 
members of dissimilar materials. 

Thermal Conductivity. The conductivity of a metal is its 
ability to transmit heat throughout its mass. This property, which 
is not the same for all metals and varies within wide limits, is of great 
importance to the welder. It can be seen that if one metal conducts 
or transmits the heat from the welding blowpipe more rapidly through- 
out its mass than another, it is necessary that allowance be made both 
as to the pre-heating equipment and the size of the blowpipe used." 

In welding metals of high thermal conductivity, it is necessary 
to use oversize blowpipes — as in the case of copper. Although the 


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melting point of copper is low, yet the conductivity is high, and, 
consequently, a blowpipe of the same size as would be used on a 
similar section of steel must be used. 

The conductivity of a metal will have a great bearing on the 
consideration of expansion and contraction. If one metal absorbs 
or leads the heat away from the welding blowpipe more rapidly than 
another, the heated area will become very much larger, and, conse- 
quently, the expansion and contraction more severe. 

Specific Heat. The specific heat of a metal is the amount of 
heat that is absorbed when it is raised through a certain range of 
temperature. A metal having a low melting point but relatively 
high specific heat may require as much heat to bring it to its point of 
fusion as a metal of high melting point and low specific heat — as in 
the case of aluminum compared to steel. 

Coefficient of Expansion. The linear increase per unit length 
when the temperature of a body is raised through one degree is its 
coefficient of expansion. 

The coefficient of expansion varies materially with the different 
metals. Of the metals most commonly welded, as seen from Table I, 
aluminum has the greatest expansion, bronze and brass next, then 
copper, steel, and iron. Aluminum expands almost twice as much 
as iron or steel, consequently, in dealing with aluminum work it is 
necessary that this feature be considered very seriously. 

Expansion and Contraction. When a body of any material is 
subjected to an increase in temperature, it expands and its volume 
and linear dimensions are increased. When the temperature is 
lowered a reverse action takes place, the body contracts, and its 
volume and linear dimensions decrease. Metals or metallic bodies 
are very susceptible to this change in volume due to variations ; n 

The effect of this expansion and contraction is of great impor- 
tance to the welder. It is impossible for the welder to produce satis- 
factory work until he has a knowledge of the nature and the amount 
of expansion usually encountered and of how to compensate for it. 

The expansion and contraction of the welded piece cannot 
be controlled or arrested mechanically, because the force of expansion 
is irresistible. In malleable, or ductile, metals the expansion is liable 
to produce warping or deformation of the piece, while in materials 


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that are not of this nature — brittle materials — such as cast-iron, the 
result of the expansion and contraction, unless properly taken care of, 
is fracture. 

If the expansion can take place in all directions, it will give the 
welder no trouble, as the piece will expand equally all over, and upon 
cooling will contract to its original volume. If, however, the welding 
takes place at a point that is confined by various parts or by the par- 
ticular construction of the piece, it is then necessary to give it due 

The resultant effect of contraction, produced by the cooling of 
the welded object, must be considered equally with that of expansion 
Contraction produces as much cracking, or checking, and warping as 
does expansion. Therefore, it is essential that the welder study not 
only the effect of expansion, but also the subsequent result produced 
by contraction. 

Methods of Handling Expan- 
sion and Contraction. There are 
many ways of taking care of 
expansion and contraction, such 
as heating the entire piece to a 
dull red heat, simultaneously 
heating opposing similar parts, 
and breaking the piece at certain 
points to allow free expansion and then re-welding at the break. If the 
material is ductile or malleable, it may be warped or bent out of 
shape to such an extent that the spring will take up completely the 
opposing force of expansion and contraction. This, however, entails 
an accurate calculation and should not be used except where no other 
means are feasible. 

Handling Simple Case of Expansion and Contraction. We will 
first consider the simplest condition of welding. Assume that a long 
bar which is free at each end has broken at point A, Fig. 35. In this 
case the welding may be carried out without any fear of encountering 
difficulties due to expansion and contraction. The bar is free to . 
expand and contract at each end. While there might be some warp- 
ing or deformation due to the heat of welding if the blowpipe is not 
handled properly, yet, there is very little danger of weakening the 
weld because of internal strains. 

Fig. 35. Simple Case of Expansion and 


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Now let us assume that this bar is part of a casting, as shown at C, 
which is surrounded and joined to a rigid frame B and D. In this 
case the expansion and contraction due to welding must be taken 
care of. It is readily seen that the expansion is not the force that will 
cause trouble, because when the two pieces expand during welding, 
the metal, which is in a fused condition, is so soft that the expansion 
can take place in the weld and the edges will approach each other. 
This will not affect the confined frame. However, consider the action 
on the metal when it starts to cool. Contraction sets in and, as it is 
irresistible, there must be some compensation for the shortening of 
the bar C. If the material is ductile and one that will stand bending, 
deformation or warping will occur. But, if it is of low ductility, such 
as cast iron, a break will occur either at the weld or at a line of less 

Methods of Handling. In welding an article of the general 
nature, shown in Fig. 35, when the break is in an internal member, 
such as at C, there are several ways of handling it. 

Heating Entire Casting. The entire piece can be raised to a high 
temperature as referred to above and in this way produce an expan- 
sion in the entire mass, and, consequently, equal contraction. How- 
ever, this is not necessary, and in some cases is not possible; the 
operation also takes more time and costs more. It is only necessary 
at the time of welding to heat simultaneously similar parts to a good 
red heat, in order that the stiffness of the frame may be lessened, and 
thus take care of the contraction. 

Heating Confining Members. In the example referred to, the 
application of a pre-heating burner at the points B and D will cause 
the frame to expand in the linear direction of the expansion and con- 
traction produced by the weld. Therefore, when the weld is finished 
and the frame starts to cool and contract, the parts B and C, in as 
much as they were raised to practically the same temperature as the 
metal surrounding the weld, will contract equally and, therefore, a 
successful weld will be produced. 

Use of Wedges. If it is impossible to apply pre-heating at the 
points referred to, another method may be used. By the use of 
jacks, wedges, or similar devices, a casting such as shown in Fig. 35 
may be sprung or bent out of shape, and the edges of the part to 
be welded may be separated. After the weld is executed and con- 


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traction sets in, the jacks, wedges, etc., may be withdrawn. The return 
of the sprung parts to their original positions will compensate the 
contracting strains. 

Breaking Another Member. Another method of taking care of 
expansion and contraction is that of breaking the piece at some extra- 
neous point, such as at E. In this case the expansion and contraction 
will be free to act at the point C without any fear of serious after- 
effect, as the casting is free to spring in any direction, because of the 
loose joint at E. As the point E is not confined, it is an easy matter 

Fig. 36. Complex Case of Expansion and Contraction 

to reweld this break without fear of any bad results. This method, 
however, is dependent upon the thickness of the metal and is one 
that should not be attempted unless no other means are feasible. 

While this diagram is extremely simple, nevertheless the prin- 
ciples to be considered and the methods of handling them are indenti- 
cal with those experienced in all practical work. A clear conception 
of the forces acting, the nature of their action, and how to counteract 
them, is essential in work with the oxy-acetylene blowpipe. 

Handling Complex Case of Expansion and Contraction. A good 
example of a complex case of expansion and contraction is the fly- 
wheel or pulley with broken spokes, as shown in Fig. 36. 


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Assume that the spoke is broken at A. If this were welded with- 
out considering and allowing for expansion and contraction, the 
shrinkage strain would be so great that failure would occur. 

Pre-heating the rim from W to X to a dull red heat will cause the 
rim to expand outwardly, separating the edges of the broken spoke. 
While in this state the weld should be made rapidly and then the 
entire wheel allowed to cool slowly. Thus a good weld without the 
presence of internal strains will be produced. The expansion of the 
rim, due to the pre-heating, will offset the contraction of the weld 
in the spoke. 

If the crack in the spoke is near the rim, it is only necessary to 
apply a gas or oil burner to the rim at M until it is at a red heat. 
This will expand the spoke and rim, and separate the edges of the 
break sufficiently to offset the contraction of the weld. 

The spoke may be welded at A without pre-heating if the confin- 
ing member — in this case the rim — is broken to lessen the rigidity. 
In order to do this the rim must be broken at a point P, always close 
to the spoke. First one side of the spoke is strongly tacked at the 
weld. Then the other side is welded two-thirds the way through. 
The tack is then melted out and the weld completed. The rim is then 
welded at point P. If the edges do not meet accurately, they may be 
brought to do so by heating either at M or 0, according to which edge 
is low. 

If two spokes are broken as at A and B, the same general pro- 
cedure as given above may be followed. In case it is necessary to 
pre-heat a large portion of the casting it is important that the pre- 
heated area always extend beyond the spokes adjacent to those 
fractured, from Y to Z. 

If two diametrically opposite spokes are broken such as B and C, 
each may be treated as independent of the other and welded by any 
of the methods given above. 


Reasons for Pre-Heating. Pre-heating is employed for three 
fundamental reasons: 

To Compensate for Expansion and Contraction. When pre-heat- 
ing is used to counteract the effects of expansion and contraction, it 
is necessary that the casting be heated either in certain confined 


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localities or entirely to a dull red, or in some cases to a bright red heat. 
With this treatment the internal strains existing in all welds are 
reduced to a minimum. 

To Decrease Cost of Welding. When a weld is being executed 
on a large casting, it is too expensive to supply the total amount 
of heat required from the blowpipe alone. To offset this, pre-heating 
by some cheaper method is used, and the result is usually a saving 
of from 25 to 60 per cent of the cost of welding by means of the blow- 
pipe alone. Then, too, it is possible to accomplish the welding with 
greater speed, due to the casting being at a higher temperature. 

To Make Metal More Receptive to Action of Welding Flame. When 
the temperature of a metallic body is raised, the state of the metal 

Fig. 37. Pro-Heating with Welding Blowpipe Fig. 38. Gas Burner for Pre-Heating 

surrounding the weld is more nearly that of the molten metal in the 
weld, and the result is a more homogeneous and smoother-grained 
union, dependent upon the temperature reached in pre-heating. 

Methods of Pre-Heating. There are various means of carrying 
out this preliminary heating. The method used should be governed 
by the particular work in hand. 

Pre-Heating with Welding Blowpipe. The simplest method and 
the one most used on light objects is that of utilizing the flame of the 
welding blowpipe, Fig. 37. In welding thin castings, it is only 
necessary that the flame of the blowpipe be played upon the parts at 
the line of the weld for a few moments, in order that the pieces may 
obtain a red heat. This is, however, expensive, and should only be 
employed on small objects. 

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Gas and OH Burners. If the article to be welded is of fairly large 
size, the use of gas, Fig. 38, or oil burners, Fig. 39, is economical. 

Fig. 39. Oil Burner for Pre-Heating 

Courtesy of Oxweld Acetylene Company, Chicago, Illinois 

Fig. 40. Charcoal Fire for Pre-Heating Castings 

These pre-heating torches, however, limit the area of the surface 
covered, so consequently are used more successfully on that work 


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which requires localized pre-heating. The flames produced are of 
sufficient temperature, but not the necessary volume to evenly heat 
the entire casting. 

Charcoal Fire. The most satisfactory method of pre-heating is 
by means of a charcoal fire built around the article to be welded. 
The usual procedure is to build a small temporary fire-brick furnace 
around the piece and fill in with charcoal, Fig. 40. This is ignited by 
means of kerosene. As the progress of the ignition of the charcoal 
is rather slow, the pre-heating is carried out gradually. The nature of 
this pre-heating flame is of such evenness and volume that the tem- 
perature imparted to the casting is the same throughout its mass. 

In welding large castings of a complicated nature, such as engine 
cylinders, it is necessary that they be pre-heated evenly throughout 
and that the welding be carried on while the casting is at a dull red 
heat. Therefore, the most satisfactory means of accomplishing this 
is by embedding the casting in charcoal and carrying on the work 
while it is embedded in the hot coals. 


General Considerations. The welding of steel is apparently 
simple, but in reality it is a fairly difficult material to weld and 
should receive the welder's best thought and care. It is simple to 
produce a nice looking weld that has a smooth even surface, but it is 
not easy to produce a weld that is strong and will stand up under 
service. Welds of high strength are absolutely necessary in cases like 
automobile frame and crankshaft repairs, because a poor weak weld 
might prove fatal. 

Oxidation. It is practically impossible to prevent a certain 
amount of oxidation; but it is very important that it be kept to a mini- 
mum. The oxide that forms on the top of the weld may be removed 
quite easily, because it melts at a lower temperature than the metal. 
It may be floated off the weld while hot, or removed as a thin skin 
after the weld becomes cold. Care must be taken, when adding the 
welding rod, Fig. 30, page 32, that this film of oxide is penetrated, 
because if this is not done the oxide will be incorporated in the weld, 
which will therefore be very weak. 

Expansion and Contraction. The effect of expansion and con- 
traction is not as severe in steel welding as in cast iron or aluminum; 


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but, nevertheless, it must receive due consideration. In steel castings 
it is taken care of in a manner similar to that used for cast iron, that 
is, by pre-heating. In sheet-steel work the creeping, or drawing, of 
the edges is taken care of by arranging the edges of the sheets at an 
angle, or by tacking, or by the use of jigs to hold the work. 

Welding Rod. Each welding head is designed for use with a 
certain thickness of metal. As the volume of the flame varies with 
the size of the welding head, care must be used to select a welding 
rod of the correct size in making welds in sheets of various thickness. 
There is great danger of burning a welding rod that is too small, or, 
if the rod is too large, it may not melt through and will enter into the 
weld in a semifused condition and not be thoroughly incorporated in 
the weld. The following table shows the proper size of welding rod 
to be used for the different thicknesses of sheets: 

Thickness or Sheet Sue or Welding Rod 

Up to J inch A i nc h 

J to A inch J inch 

J to | inch A inch 

\ inch and over \ inch 

Never use twisted wire made up of two or more strands, because 

this offers a very large surface for oxidation, which is a condition 

operators must try to avoid. 

Neutral Flame. The importance of maintaining a neutral flame 
at all times cannot be emphasized too strongly. An excess of acety* 
lene in the flame tends to carbonize the N work, resulting in a hard 
brittle weld; while an excess of oxygen will oxidize or burn the metal. 
It is seldom necessary to adjust the flow of gases through the blowpipe 
after correct adjustment has once been made, except in the case of 
very heavy welding where the intense heat of the molten metal tends 
to expand the orifice in the tip of the welding head. This has some 
effect on the size and shape of the flame and necessitates more or less 
frequent adjustment to keep the gases in correct proportion to main- 
tain the neutral flame. 

Movement of Blowpipe and Addition of Welding Rod. In welding 
sheet steel, it is necessary that the oscillating movement previously 
referred to be imparted to the blowpipe and used continuously — 
both because of its high-melting point and the behavior of the molten 
metal under the action of the blowpipe flame. Steel cannot be pud- 


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died and it is therefore necessary to add the filling material in thin 
overlapping layers. The importance of securing a perfect bond 
between every two layers can be readily seen. To make a true weld, 
a simultaneous fusion of the edges of the sheets and the welding rod 
must be produced. 

To do this with light- and medium-weight sheets, a motion is 
imparted to the blowpipe which will cause the flame to describe a 
series of overlapping circles as previously described, page 28. This 
overlapping extends in the direction of the welding and, in order to 
make a weld of good appearance, must be constant and regular in 
its advance. 

In heavier plates, while the same rule governing simultaneous 
fusing of the edges of the sheets and welding rod apply, the filling of 
the groove is accomplished in a slightly different manner. On 
account of the depth of the weld the flame is not large enough to 
fuse a body of metal of so great an area, and it is impossible to fill the 
groove entirely from bottom to top with one layer of metal. The 
bottom edges of the groove must first be thoroughly fused for an inch 
or two before adding metal. When this is done, bring the flame back 
to the starting point and when the metal is in the proper molten 
condition add the filling material, oscillating the blowpipe in a series 
of semicircles, as previously recommended for welding heavy sections, 
page 29. Follow this method of filling the groove in sectional layers 
until the proper height is reached, making sure that thorough fusion 
is accomplished between the layers themselves and the edges of the 
sheet and the layers of filling material. 

After- Treatment. Correct after-treatment is as essential for 
successful welding of steel as the actual welding operation. Proper 
after-treatment will improve the grain of the metal and will materially 
increase the strength and toughness of the weld. There are three 
principal treatments that will benefit the material and are easily 
employed in the repair shop. These are called annealing, hammering, 
and quenching. 

Annealing. Annealing consists of reheating the work to the 
proper temperature and then allowing it to cool slowly. The work 
should be heated to a bright cherry red by means of a blowpipe or 
suitable burner, or in a furnace that can be carefully regulated. Care 
must be taken that the work reaches the bright cherry red, because 


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heating to a lower temperature will be detrimental and may leave the 
weld weaker than if not annealed at all* After the work has been 
heated, it should be allowed to cool very slowly and evenly. It 
should be covered over with asbestos or dry sand, packed in lime, or 
left to cool in the furnace. Care must be taken that cold air currents 
do not strike the work before it has become cold. 

Hammering. Hammering consists of reheating the weld to 
the proper temperature and then hammering while at this tempera- 
ture with a hand hammer. The weld should be heated to a bright 
yellow heat and then hammered with quick light blows. Heavy 
hammers or heavy blows should never be used. The hammering 
should cease as soon as the weld falls to a dull red, for otherwise 
the fine grain of the metal will be spoiled and the weld will be weak. 

Quenching. Quenching consists of reheating the work to the 
proper temperature and then plunging it into water, brine, or oil. 
This method is used mainly for small articles. It is used quite often 
for hardening and tempering. Quenching should be employed only in 
special cases, because, although it will make the work strong, it will 
also make it hard and brittle. 

Light Sheet-Steel Welding 

Preparation. In welding two short pieces of flat steel, up to A 
inch in thickness, no special preparation of the plates is necessary, 

except to have them flat as possible 

and to be sure that the edges are 

reasonably true. The two pieces of 

metal should be placed on a level 

surface, preferably fire brick or 

some other nonconductor of heat. 

Expansion and Contraction. 

With light sheet, expansion and 

contraction are cared for by tacking 

the seam at certain intervals or by 

arranging the sheets so that the 

Fig. 41. Ught sheets in Portion for edges to be welded are set at a 

e ^ ag slight angle rather than parallel, 

Fig. 41. The correct amount of divergence is determined by the 

thickness of the metal and should be from 2 J to 6 per cent of the 


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length of the weld. The amount of divergence between these limits 
varies also with the speed of welding, fast welding requiring less 
spread. After the plates are in this position, place two pieces of flat 
bar steel on each side, about £ inch from, and parallel to, the line of 
the weld. Clamp or weight these pieces down so that they cannot 
be readily moved. The work is now in position for welding. 

Jigs. In making this type of weld in flat sheet steel in longer 
lengths, up to several feet and up to -&- inch in thickness, a welding v 
jig made up with two slotted jaws hinged at one end and provided 
with hold-down clamps at the other end will be found more conven- 
ient than the individual hold-down bars. 

Fig. 42. Jig for Holding Light Sheet Cylinders for Welding 

For welding short cylinders, a jig made similar to that shown in 
Fig. 42 will be found satisfactory. 

Tacking. Tacks, or short welds, at intervals of from 2 to 6 
inches, according to the thickness of the sheet, can be made the entire 
length of the seam to hold the edges in position for welding if jigs 
are not available. 

One of the above methods must be used to take care of the 
creeping action due to expansion when the flame of the blowpipe 
is applied to the metal. If this action is not provided against and 
the two sheets are placed with parallel edges, they will first diverge 


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when the welding is started, as in a, Fig. 43, and then gradually come 
together. When about half of the weld has been made, they will again 
become parallel as in b. From this point on as the welding continues 
the sheets will draw together until they overlap, as shown in c. 

(a) (6) (c) 

Fig. 43. Result of Not Providing for Expansion 

Welding Light Sheet Select the welding head and a piece of iron 
welding rod of the size suitable for the thickness of the sheet and 
place the work in position for welding. 

As steel is very sensitive to the action of the carbonizing 
flame and particularly to that of the oxidizing flame, a constant, 
nonvarying, neutral flame should be maintained. The incandescent 
jet should be of maximum size and clear outline at all times. 

With the correct neutral flame, start welding at the point 
where the two sheets meet. Impart the circular motion to the 
blowpipe, described under Movement of Blowpipe, page 28, to 
produce the correct rippled surface on the finished weld. When the 

Fig. 44. Appearance of Good Weld in Light Fig. 45. Appearance of Poor Weld in Light 
Sheet Steel Sheet Steel 

weld is finished, turn out the blowpipe and allow the work to cool 
until the metal is black. 

Then remove the hold-down bars and examine the weld. I* 
you have followed instructions, your weld will have the appearance 
shown in Fig. 44 and will not be like that shown in Fig. 45. On 


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closer examination you will find that all the particles of dirt and 
impurities you noticed floating on the top of the molten metal when 
you were welding are now lying with the oxide 
on top and alongside of the weld where they can 
be readily brushed or scraped off. Now take s ^Lve?Cu!& 
your job to the shears and. cut off one or two 
pieces. Upon examination, the cross-section should present the 
same uniform texture and color in both the weld and the sheet. 
Types of Welds in Light Sheet Lap Weld. Lap joints, either 
single or double, Fig. 46, should never be used 
in welding sheets of any thickness because ^■■^■■■■^■■^ 

the weld will be subjected to a shearing strain. Fig. 47. Butt weld in 

ttt 1 1 1 1 1 1 1 . u ^ ht 8heet 

Welds should be under tension or compres- 
sion strains, never under shearing or bending strains. 

Butt Weld. The most common and the simplest weld to prepare 
in light sheet is the butt joint, shown in Fig. 47. 

Flange Weld. Another type of weld in light* ^^™^^"^™ Bfc ' 
sheet, but one that entails some preparation, is **• 4 \ ig 5sgrt* dd in 
made by flanging up the welding edges about -fa 
to & inch, Fig. 48, laying the two pieces flat and parallel on the weld- 
ing table and executing a flange, or 
edge, weld. It is not necessary to 
use welding wire with this type of 
weld, because the metal in the 
flanges when they are fused to- 
gether acts as a filling agent. By 
careful manipulation the edges can 
be fused down to a small bead, 
practically flush with the surface 
of the sheet. 

Cylinders. In welding light 
sheets that have been rolled in 
cylindrical form, the separation of 
the edges can be accomplished by F - 49 Method of Welding LiKht sheet 

placing a Wedge about tWO-thirds Winders-Uaing Wedge to Space the Edges 

of the way down the length of the seam after the welding is started, 
Fig. 49. As the welding progresses the wedge should be moved further 
along the seam and withdrawn entirely as the work nears completion. 


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Tacking can also be resorted to in welding cylindrical forms, 

although this results in the deformation of the cylinder, as shown 

in Fig. 50, and makes it necessary 
to hammer or re-roll the cylinder 
into shape. 

The edges of very light sheet 
cylinders can be flanged and an 
edge, or flange weld, executed; but 
this method cannot be recom- 
mended with sheets heavier than 
tV inch. 

Corner Welds. In making a 
corner weld in the lighter gage 
sheets up to A inch, the edges of 
the sheet should be flanged, as 
shown in Fig. 51. In sheets from 

XZJ^M&&*ffi$^ A to A inches in thickness, it is 

only necessary that the edges of 

the sheets run as true as possible in position, as shown in Fig. 52. 

Tacking is necessary in this case, as the sheets, due to expansion, 


Fig. 51. Corner Weld Fig. 52. Corner Weld Fig. 53. Sharp Corner 

for Very Light Sheets, for Light Sheets, A to Weld for Light Sheets 

up to A Inch Thick A Inch Thick 

readily move out of position when welding is commenced. On welds 
of this latter type it is necessary to use welding wire. 

Two other forms of corner 
welds are illustrated in Figs. 53 
and 54. These sheets should be 
tacked and, if ^ inch or thicker, 

Fig. 54. Broad Corner Weld for Welding wire should be USed. 

Light8heet8 Tank Heads. In making 

tanks when either a bottom or heads in both ends are required, the 
method of putting in the heads is governed by the design and pur- 
pose for which the tank is intended. 


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Storage Tanks. If the tank is to be used as a storage receptacle, 
such as gasoline tanks, the heads can be cut to the outside diameter 
of the shell, laid flat on the end of the shell and tacked at intervals 
all the way around, Fig. 55. Then the shell, with the heads securely 
tacked in place, is laid on its side and the welding is started at any 
point, the tank being turned, from time to time, as the welding 
progresses. Or, the heads can be flanged to any depth desired, 
and backed into the shell until the edge of the flange and the edge of 
the shell are even, Fig. 56, making sure that the head fits the shell 
snugly. They are then tacked and welded in an upright position. 
This latter method is the better of the two from the welding stand- 

Pressure Tanks. When a tank is built to stand a considerable 
pressure, such as air-compressor tanks, the heads should always be 
dished and flanged, the boiler-maker's standard specifications govern 

Fig. 55. Head Weld 
for Storage Tanks 

Fig. 56. Head Weld for 
Storage and Medium- 
Pressure Tanks 

Fig. 57. Head Weld 
for Pressure Tanks 

this. The heads can be either backed in and an edge weld made, 
Fig. 56, or set up so that the edges of the flange exactly meet the 
edges of the shell, Fig. 57. In either case the parts should be tacked 
together before welding. In the second case, care should be used 
in flanging to have the outside diameter of the flange exactly the 
same as the outside diameter of the shell. This method is the best 
because the weld is under direct tension or straight pull. 

Tubes. Light-weight tubing should be squared off and fitted 
nicely before welding is attempted. It should be tacked in several 
places and then welded. 

Heavy Sheet-Steel Welding 

Preparation. In welding heavy sheet metal above A inch in 
thickness, a certain amount of preparation is necessary. The 
success of the weld depends in a great measure upon the proper 


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preparation of the work to be welded. While the preparation is 
governed largely by the particular location of the weld and form 
of the sheets to be welded, there aie certain general rules that must 

always be observed. 

In making a perfect 
weld it is necessary that 
the metal at the weld 
be completely fused 
throughout its entire 
thickness. In light sheets 
the projection of the 
flame is great enough to 
produce this result, but heavy sheets would require a flame of such 
magnitude that it could not be readily handled. Therefore, in order 
to facilitate complete fusion, the edges of the sheets to be welded are 

Fig. 58. Heavy Sheets in Position for Welding 

Fig. 59. Welding Heavy Plate Steel Cylinder 
Note grooving of edges, spacing clamps and wedge about ball way along the seam 

chamfered or beveled to form a V-groove, the width of this V being 
equivalent, or nearly so, to the thickness of the metal. 


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Expansion and Contraction. With heavy sheet, expansion and 
contraction are cared for by observing the same rules of spacing, 
Fig. 58, and clamping, Fig. 59, or, in some cases, tacking, in order 
to hold the work in position for welding, as described for light 
sheets on page 47. 

Welding Heavy Sheet. Select a welding head and a piece of 
iron welding rod of the proper size to accomplish the work in hand. 

Because steel is sensitive to the carbonizing and oxidizing flames, 
it is necessary to maintain the correct oxygen pressure and a neutral 
flame at all times. In ordinary heavy sheet welding there are two 
general methods of procedure, either of which will produce a good 
weld when properly executed. These methods may be called weld- 
ing by sections, and continuous welding. 

Welding by Sections. Welding is started by first playing the 
flame of the blowpipe along the edges of Ihe pieces to be welded. 
This is done merely as a preliminary heat treatment. The flame 
is then played on the bottom of the groove at the beginning of the 
weld until the edges are in a molten condition, at which time the 
blowpipe is momentarily withdrawn and the molten metal allowed 
to flow together. This is done without the aid of any filling material. 
Care must be exercised at this point, because successful welding 
depends upon complete penetration and perfect union of the bottom 
edges. When a perfect union of the two members is secured for 
about one or two inches, the welding rod is brought into use. By 
playing the flame around the welding rod in contact with the edges 
of the weld instead of directly on the welding rod, it is possible 
to bring them both to the point of fusion simultaneously. The rod 
is then gradually added to the weld, layer by layer, until this par- 
ticular section of the weld is built up to the required height. The 
flame is then played on the face of the metal just added and on the 
bottom of the groove until fusion of these parts is secured. The 
welder then repeats the operation described above until the next 
small section of the groove is filled up to the proper level. The 
welding progresses by means of these small sections, each being built 
up completely before another is started. 

While the metal is in a fused condition, the velocity of the flame 
will cause the molten metal to become slightly indented. The 
flame should be withdrawn momentarily, from time to time, thus 




allowing the fluid metal to flow back to its normal level, in which 
position it will solidify. Skill in steel welding depends greatly on 
this manipulation, as the flowing together of the different molten 
centers produces the weld. 

Continuous Welding. In this method the weld advances con- 
tinuously with each addition of metal. By this method the metal 
is added in short layers, sloping rather than horizontal. The weld 
is started by fusing together the bottom edges of the groove as pre- 
viously described. The filling material is then added so that it 
will be from J to \ inch high at the starting point and slope to nothing 
in a length of 1 or 1 £ inches along the bottom of the groove. This 
will give an inclined surface to which the filling material is added 
in parallel layers. The added metal being on a sloping plane, the 
fusion of the bottom edges is always carried ahead with the welding, 
as each layer includes a small section of the bottom of the groove. 

Types of Welds in Heavy Sheet. Lap Weld. As explained on 
page 49, the lap weld should never be used. 

Butt Weld. The beveled or grooved butt joint is the only 
welded joint that should be employed on heavy sheets, Fig. 60. 

The most satisfactory method of 
handling the work is to space the 
edges, because tacking is very 

Pig. 60. Butt Weld in Heavy 8heets ,., , A , , , , . 

likely to not hold on heavy sheets. 

Never weld sheets from both sides, because unequal strains 
are likely to be introduced by localized heating when working on 
the second side. 

Cylinders. Heavy cylinders should also be prepared for the 
grooved butt weld, for the same reasons as for heavy sheets. 

| CO ■ (b) 

Fig. 61. Corner Welds for Heavy Sheets 

Corner Welds. The two most satisfactory corner welds for 
heavy sheet are shown in Fig. 61. Although the second is a little 


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more costly to prepare, it is more satisfactory than the first because 
it insures better penetration. 

Tank Heads. In welding bottoms or heads in tanks of heavy 
sheet, the purpose for which the tank is to be used governs the method 
of constructing the heads as it does in welding tanks of lighter gage. 
The same general rules apply in both cases, the main difference being 

Fig. 62. Head Weld for Fig. 63. Head Weld for Fig. 64. Head Weld for 

Storage Tanka Medium-Pressure Tanks High-Pressure Tanks 

that the edges of the heavy shells and heads are chamfered, de- 
pendent on the design of the tank. All require tacking to hold the 
members in position for welding. 

Storage Tanks. In the case of putting on a flat head, the edge 
of the head only is chamfered, Fig. 62, while in putting in a flanged 
head where an edge weld is to be executed, as in Fig. 63, both shell 
and head are chamfered to make the V-groove. 

p D D 

Fig. 65. Welds for Tank Reinforcing Rings 

HighrPressure Tanks. When a head is put in, as shown in 
Fig. 64, both the edge of the flange and the edge of the shell are 
chamfered. This type of head is the best for high-pressure tanks 
because the weld is in tension. 

This method also applies to the welding of two cylindrical 
shells end to end in making tanks of such dimensions that one 
single sheet of steel is not large enough to make a complete shell. 


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Tank Rings. In welding angle-iron rings to tanks of the same 
thickness, it is necessary that the edges of both ring and shell be 





Fig. 66. Various Pipe Joint Welds 

beveled as at the left, Fig. 65. Two methods of welding heavy 
rings to lighter shells are shown at the middle and right. The inside 
weld at the right should be only enough to smooth off the joint. 

If too much heat is applied from the 

inside there is likely to be trouble from 

warping or buckling. Rings should always 

be tacked to prevent bowing, twisting of 

Fig. 67. welds for Pipe Heads t h e rings, and buckling of the shell. 

Tubes and Pipes. Various tube and pipe welds are given in 

Fig. 66. 

The methods for closing the end of a pipe with a head are 
shown in Fig. 67. The first is the easier and stronger of the two. 


Fig. 68. Welds for Pipe Flanges 

Three methods of welding flanges to pipe are shown in Fig. 68. 
The first method is easier to weld than the second ; but the latter 


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Fig. 69. 

Preparation of Heavy Forgings for 

is the stronger. The third method is the best method of welding 
flanges to pipe, but is, of course, a special type of flange. 

Welding Heavy Steel Forgings and Steel Castings 

Preparation. In welding heavy steel sections, such as crank- 
shafts, axles, and the like, the weld is prepared by grooving or beveling 
from both sides. This is done 
because it is easier for the oper- 
ator to do the work and for the 
sake of economy, because by 
beveling from both sides less 
filling material is necessary and, 
consequently, less time and gas 
are needed. 

Square Sections. Square or rectangular sections of forgings 
are best prepared by beveling half way through from each side, 
Fig. 69. After the welding has 
been carried on from one side, 
the piece turned over and the 
welding completed from 
the second side, there will 
probably be a slight bow, or 
curve. In the case of forgings, 
this is not objectionable, be- 
cause the work can be, and, in fact, should be, reheated and straight- 
ened. The reheating in the case of forgings is beneficial to the grain 
of the material and the 
strength of the weld. With 
castings, however, this bend- 
ing is not possible. There- 
fore, to keep the work in 
alignment, it is best to pre- 
pare the work as shown in Fig. 70. The welding is carried on two- 
thirds of the way through from the first side, and then finished 
by turning over and working from the second side. 

Round Sections. Round or elliptical sections should be prepared 
by beveling the ends to a wedge as indicated in Fig. 71. They should 
never be turned down to a point. By preparing the pieces as shown 

Fig. 70. 

Preparation of Heavy Castings for 

Fig. 71. Preparation of Round Sections for Welding 


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in the illustration, the welder will have a flat surface to build his 
weld upon. If the work were prepared to a point, the filling material 
when added would have no surface to lie upon and would run down 
in drops, necessitating burning or melting away when the work 
is tinned over, and probably resulting in a weak weld with con- 
siderable oxide. 

Expansion and Contraction. Expansion and contraction will 
probably cause very little trouble to the operator in the case of 
shafts and other heavy pieces that are not connected. The only 
difficulty the operator will encounter in these cases will be the possible 
bending, which was noted above, when welding from two sides. 
However, if the broken part is confined by rigid members, the work 
should be handled either by pre-heating, or one of the other methods 

recommended and ex- 
plained under Expan- 
sion and Contraction, 
pages 36 to 40. 

V-Blocks. When 
welding shafts, it is ad- 
visable to line them up in 
position on V-blocks, so 
that they may be turned 
over and still kept in 

Fig. 72. "V Blocks for Welding Shafts alignment, Fig. 72. 

Welding Heavy Section. In the case of a heavy section select 
the proper size welding head and a piece of welding rod of the cor- 
rect analysis for the particular work at hand, and place the work in 

If the section is over or about one inch, it should be pre-heated 
by means of a gas or oil burner until it is at a red heat. This will 
save oxygen and acetylene, and will bring the material to a tempera- 
ture at which it will be more receptive to the action of the welding 
flame and thereby insure a more homogeneous weld. If not objec- 
tionable to the operator, it is advisable to let the pre-heating burner 
play on the work while the welding operation is going on, taking 
care, of course, that the materials of combustion of the pre-heating 
burner do not strike the molten metal and have a detrimental effect 
on the weld. 


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The welding flame is first played on the edges at the bottom of 
the groove until they are in a molten condition. The flame is then 
momentarily withdrawn to allow them to flow together and "set", 
and form the bottom of the weld. When a perfect union of the bottom 
is secured all the way across, the welding rod is brought into use. 
By playing the flame around the welding rod and the edges of the 
weld instead of directly on the welding rod, it is possible to bring 
them to a fusing temperature at the same time. The rod is then 
gradually added to the weld, layer by layer, until the entire groove 
has been filled up. The welding rod is kept plunged into the molten 
metal all the time to prevent oxidation. Any oxide that forms during 
the welding is floated to the top and removed by scraping with the 
welding rod, or by blowing away with the force of the welding flame. 
The welder must be careful that he does not allow the molten metal 
to run over the sides of the weld. Each layer is added in such a 
way that it extends slightly beyond the end of the groove. Then, 
from time to time, as the groove is filled up, the operator smooths 
down the two ends. 

Hammering. As each section, about \ inch thick, is added 
to the groove, the operator stops the welding operation, heats the 
work to a bright yellow, and hammers the weld lightly but rapidly 
to give it as fine a grain as possible. After the weld has been com- 
pleted, it is either hammered or annealed, as directed on page 45. 


General Considerations. Many defects are experienced by the 
beginner in welding cast iron because of its peculiar properties. The 
two principal faults noticed are the production of hard, glassy, and 
brittle metal in the weld, and subsequent cracks, breaks, and checks 
either in the weld or in the adjacent metal, owing to excessive internal 
strains set up by unequal contraction. Both are serious defects, and 
the liability of their occurrence is so great that proper preventive 
methods should be continually borne in mind and applied while 
welding this material. 

Oxidation. Cast iron melts at about 2000° to 2190° F., and 
iron oxide melts at about 2450° F. The oxide is formed, however, 
at low temperatures, a bright red heat being sufficient to cause 
the combination of oxygen from the air with the iron of the casting. 


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It is not possible to melt this oxide and flow it from the weld, so it 
remains in the casting in the form of thin flakes or crust. This 
not only prevents the alloying of the molten metal, but also combines 
with the free carbon and is, consequently, conducive to the formation 
of white iron. Therefore, this oxide must be removed or destroyed. 

Expansion and Contraction. Cast iron is absolutely lacking in 
elasticity, and its tensile strength is very low. In preparing work 
for welding, it is always necessary to take fullest precautions against 
the bad effects of expansion and contraction. Expansion and con- 
traction should be treated with more importance in the welding of 
cast iron than in any other metal. 

When the internal strain produced by contraction is greater 
than the tensile strength of the section to which it is confined, fail- 
ure will occur. When the strain is not great, but still exists, the 
resistance of the section to external stresses is reduced in proportion. 
Thus a casting may appear to be normal after welding but the 
excessive internal strains caused by the welding may make it fail 
at the slightest shock. 

One of the three general methods of coping with the forces of 
expansion and contraction, which are given on pages 36 to 40, 
must be used when welding cast iron. The proper method to pursue 
is determined by the size and shape of the casting and the nature 
and location of the break. A very large percentage of the failures 
due to shrinkage cracks may be prevented by an intelligent anticipa- 
tion of the forces of expansion and contraction and the proper hand- 
ling of the work to overcome these. 

Pre-Heating. Pre-heating should be used to some extent in 
all cast-iron welding. If the piece is small and the break is so located 
that it is not necessary to consider expansion and contraction, the 
blowpipe should be played upon it until the chill is removed from 
the casting. If the casting is large, an oil or gas burner, or charcoal 
fire can be used. In a large casting this preliminary heat treatment 
not only favors the execution of a good weld but also requires less 
oxygen and acetylene because of this large volume of heat from a 
cheap source, thereby reducing the cost of welding. 

Welding Rods. The success of cast-iron welding depends 
greatly upon the selection of a suitable welding rod. It has been 
proved time and again that hard, brittle, and weak welds have been 


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produced for no other reason than because inferior filling material 
was used. 

The presence of silicon in proper proportion tends to produce 
a soft gray-iron weld. It increases the fluidity of the metal, retards 
oxidation, and prevents decarbonization and blowholes. The 
success of the filling rod is dependent upon the amount of this ele- 
ment it contains. From 3 to 4 per cent is the average silicon content 
of good welding rods. The welding rod must be of high-grade cast 
iron, soundly cast and absolutely homogeneous. It must be free from 
all sand, grit, and rust. For convenience in handling, it is usually 
cast in 24-inch lengths of three diameters, i, f, and £ inch. In 
case either a longer or heavier rod is desired, two or more are welded 

Flux. The principal problem that confronts the welder is to 
prevent the formation of oxide, and in case it is formed, to reduce 
it and remove it from the weld. If this is not done, the molten 
metal will be enclosed in a thin film of nonmetallic material, and 
any additional metal that may be fused or added will adhere to this 
film rather than break through it and fuse homogeneously with the 
other metal. It is not possible to satisfactorily break up this film 
mechanically, therefore it must be reduced to a molten, or slag, 
condition. To accomplish this a suitable flux is used that will dissolve 
the oxide. 

A flux is not used solely to dissolve the oxide, but also to float 
off other impurities, such as sand, scale, and dirt. It forms a 
protecting glaze on the weld and surrounding surfaces and increases 
the fluidity of the molten metal. 

Borax and salt (sodium chloride) are two compounds often 
used by welders, but they really contain little merit as a flux. Their 
low fusibility seems to be the only point in favor of their use. 
Occasionally, they may be employed to advantage in welding heavy 
sections or burned iron, such as are found in firebox and grate cast- 
ings, but their function is only that of a cleanser. Both tend to 
produce hard iron. There are certain flux powders put on the market 
that contain large proportions of manganese. These powders cannot 
help but have a hardening effect on the iron. Others contain potas- 
sium perchlorate, a violent oxidizing agent. Still others contain 
material that chlorinize the weld. Needless to say, powders of this 


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kind must not be used. It is best to guard against the purchase of 
such defective mixtures by obtaining flux powders from reliable 

It is necessary that the welder learn to apply flux properly. 
An excess will cause as much trouble as an insufficient quantity. 
Blowholes may be increased in size and number by using too much 
flux. Also the molten iron will incorporate certain constituents 
of the flux if it is applied in excess. The amount to be applied depends 
upon the flux used. A welder must learn to know his flux as well 
as his blowpipe. 

The powder should be applied regularly by dipping the hot 
welding rod into it. The quantity adhering is sufficient. Do not 
throw large quantites into the weld as plenty will be added by the 
welding rod. 

Preparation of Welds. All cast iron over | inch in thickness 
should be beveled or chamfered before welding. If this is not done, 
it is necessary that the metal be burned out by the blowpipe in order 
that complete penetration be assure J. This is bad practice as it is 
almost impossible to do it without either changing the state of the 
metal in the groove due to the forced flame, or causing partial ad- 
hesion. The chamfering should be a little wider than on other 
metals for the reason that it is good practice to introduce as much 
special metal from the welding rod as possible. 

The chamfering can be done by various means. If the casting 
is light and broken in two pieces, it may be taken to an emery wheel 
and the edges ground off. If the casting is too heavy to move, a 
portable grinder or cold chisel and air or hand hammer can be used. 
If the casting is only cracked, the cold chisel and air or hand hammer 
are the most satisfactory tools to use. 

After the weld has been beveled satisfactorily, the adjacent 
metals should be cleaned about \ to £ inch from the edge. This 
is important, because all dust, sand, scale, etc., should be removed 
from the welding zone. 

To Prevent Crack from Extending. If the defect in a casting 
is a crack that shows a tendency to extend upon heating, a hole 
should be drilled in the casting a short distance from the end and 
in the direction the crack would follow. The crack will not extend 
beyond this hole, and the hole can be very easily filled in. 


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Welding Process. Although the melting point of cast iron 
not high, the total heat required to bring it to fusion is great, 
refore a blowpipe of large size is used. The speed of welding 
ncreased considerably, and the selection of the proper size blow- 
»e is influenced by the extent of the pre-heating. 

Cast iron melts very rapidly after the fusing point is once 

,ched, and when molten is extremely fluid. Because of this 

>perty, the welding should be carried on horizontally, otherwise 

i metal will flow toward the lowest point. This is not desired, 

oecause it will tend to produce adhesion. In case it is not possible 

to arrange the casting so that the weld will be horizontal, the welding 

must be started at the lower end, and skill must be used to prevent 

the too rapid advance of the molten metal. It is very difficult to 

produce vertical and overhead welds because of the fluidity. In 

welding thin sections of cast iron, the rapidity with which it melts 

and its fluidity often cause the metal to sink, bulge downward, or 

drop in. Consequently, it is necessary that close observation and 

careful manipulation be used on this kind of work. 

Flame. The incandescent jet of the oxy-acetylene flame should 
never impinge on the molten metal. The tip of this jet should be 
held at a distance of \ to £ inch from the metal according to the 
thickness. The molten iron is seriously influenced by the high 
temperature of this jet and may become oxidized and decarbonized. 
This must be rigidly observed except when it is necessary to use 
the jet to burn out sand holes, blowholes, etc. 

Manipulation of Blowpipes and Welding Rods. Because cast 
iron fuses rapidly when once the melting point is approached and 
the molten iron is extremely fluid, the circular or oscillating motion 
imparted to the blowpipe need not be so pronounced. The welding 
of cast iron is nothing but a succession of overlapping miniature 
pools, or puddles, of molten metal. 

The weld is started by playing the blowpipe on the two lower 
edges of the weld. The flame should strike the weld almost perpen- 
dicularly, because if the blowpipe is inclined, the flame will blow 
the molten metal ahead of the weld, and adhesion will result. When 
at the proper temperature, these edges are fused together without 
any filling material by the aid of a little flux. It is important 
that this first operation be carefully carried out, as the strength of 


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the weld is dependent upon a good bottom and top. When this 
first fusion has been successfully obtained, the welding rod is brought 
into play and the high silicon metal is added. With each addition, 

Fig. 73. Warm Welding Rod la Dipped into the Fig. 74. For Cast-Iron Welding, Blow- 

Flux before Each Addition to the Weld pipe and Welding Rod Are Held Almost 


the welding rod is previously dipped into the flux can, and the 
adhering flux introduced in the weld, Fig. 73. As the welding of 
cast iron is a comparatively rapid procedure, the welding rod can 

Fig. 75. Dirt May Be Scraped off by Means of the Fig. 76. Welding Rod Should Not Be 

Welding Rod Held Too Far from Welding Zone 

be held more vertically and added faster, Fig. 74. In welding "dirty" 
iron it is sometimes convenient to hold the rod in a horizontal position 
and scrape out sand, carbon, or any other dirt by means of the rod 


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as soon as it appears, Fig. 75. In this connection, it may be added 
that the welding rod should be used constantly to work out impurities 
and blowholes. The welding rod should be melted as much as possible 
in the molten metal of the weld. It should be plunged into this 
liquid, and the fusion carried out by playing the flame around it. 
The welding rod should not be held too far from the welding zone, 
Fig. 76, nor should it be added to the weld drop by drop as shown 
in Fig. 77. 

As a section of the weld is finished, it should be scraped or rubbed 
with a file while red hot, Fig. 78, to remove the film of flux, scale, 
sand, and dust that is present. This film if allowed to cool becomes 
very hard and is quite resistant to machine tools. Regardless of the 

Fig. 77. Welding-Rod Should Not Bo Fig. 78. Scraping Finished Weld with File to 

Added Drop by Drop Remove Scale 

quality of metal beneath it, many welds have been rejected because 
of the hardness of this superficial surface. 

If the weld is carefully executed and the surface is cleaned, 
it will look like the left of Fig. 79, while if poorly executed and not 
cleaned, it will look like the right of Fig. 79. 

Never go over a weld the second time if it can be avoided. In 
case it is absolutely necessary, always add fresh metal from the 
welding rod, as a failure to do this will cause a loss of silicon in the 
weld and destroy its value to the metal. 

Always perform the welding as fast as possible, because extended 
heating will tend to lower the silicon content of the weld, with the 
resultant formation of hard iron. 

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Blowholes. Blowholes occur frequently in the weld and are 
particularly troublesome if in the bottom of the weld. Their presence 
can be caused by mechanically enclosed gases or by improper blow- 
pipe handling. When blowholes appear in the weld, they should be 
instantly worked out. This may be done by forcing with the welding 
rod and applying flux. In beginning a weld, it is necessary that 
the presence of blowholes be guarded against, as it is difficult to work 
out a blow T hole at the bottom of the weld after it is finished. Occasion- 
ally, in going over a w r eld, a blowhole is discovered; this must first be 

Fig. 79. Appearance of Cast-iron Welds That Have Been 
Properly (left) and Poorly (right) Executed 

burned out by the white jet of the flame and then worked over with 
the welding rod. 

After- Treatment. The rate of cooling materially influences the 
structure of the metal in the weld. If rapid cooling is allowed, hard 
brittle iron is produced. If slow cooling is employed, soft gray 
iron is formed. Internal strains and stresses may be distributed 
and adjusted or, in some cases, eliminated by proper coolirig and 

Castings which are not large or w r hich it has not been necessary 
to pre-heat extensively may be satisfactorily annealed by playing 
the blowpipe on the weld and surrounding metal until it is at a 
bright red heat. The heated portion is then covered with asbestos 


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paper, cinders, or other nonconducting material that will retain 
the heat and protect the castings 'from air currents. For small 
castings, a barrel or bin of hydrated lime and fiber asbestos is recom- 
mended. This makes a convenient arrangement and is very satis- 
factory as an annealing agent. 

Where it is necessary to heat the entire casting in a charcoal 
or coke fire, the same temporary furnace used for pre-heating may 
be used in annealing. After the welding has been completed, the 
casting should be covered over with hot coals and ashes, and the 
furnace should be bricked up, i. e., all large, air ports closed, the top 
covered with asbestos paper, and the casting allowed to cool with 
the fire. 

The castings should never be removed from the 'annealing fire 
until they are entirely cold. This is imperative, as cold air currents 
on the warm castings may cause checks or cracks. In some cases, 12 
to 24 hours are required for satisfactory cooling. 

Use of Carbon Blocks. In case it is not possible to line up 
the weld horizontally, or it is necessary to fill in a wide hole, carbon 
blocks or steel plates are sometimes used to dam or retard the flow 
of the metal. 


Malleable Iron. Malleable cast iron, or malleable iron, as it 
is commonly called, is used extensively in castings where toughness, 
malleability, and resistance to sudden shock are required. The 
characteristic that gives malleable iron its greatest value as compared 
to gray iron is its ability to resist shocks. Malleability in a light 
casting, } inch thick and less, means a soft pliable condition and 
the ability to withstand considerable distortion without fracture, 
while in the heavy section, £ inch and over, it means the ability 
to resist shock without bending or breaking. 

In the manufacture of malleable-iron parts, white iron castings 
are packed in annealing pots with suitable material, such as mill- 
scale, borings, etc., and subjected to a cherry red heat for from 48 
to 96 hours, after which they are allowed to cool slowly. During 
this annealing process, the material in which the castings are packed 
absorbs the carbon from the surface of the casting. In this way the 
surface becomes really a steel, while the inside, or core, becomes 
gray cast iron. 


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Fusion Weld Not Possible. When malleable iron is heated 
to a fusing heat the malleable properties are destroyed and cannot 
be regained. 

Brazing Malleable Iron. The most successful method of joining 
malleable iron with the oxy-acetylene blowpipe is by brazing with 
Tobin bronze. While this gives a joint of different color, yet the 
strength, malleability, and machining qualities are satisfactory. 

The two pieces to be joined are beveled as for cast-iron welding. 
The edges are brought to a point just below fusion, great care being 
taken that they do not become fused. When the edges are at the 
right temperature, a rod of Tobin bronze is fused into the groove 
with the aid of a good brass flux. The work should be carried out by 
using a flame having a slight excess of acetylene and should be done 
as rapidly as possible to prevent oxidation of the bronze. 


General Considerations. Wlien aluminum approaches its melt- 
ing point, it does not change color in ordinary light, but retains its 
silvery appearance even when in the molten condition. When 
molten, it is very fluid and is, therefore, rather difficult to control 
under the welding flame. 

Oxidation. Aluminum oxidizes very easijy when in a molten 
condition, forming an oxide that melts at about 5400° F. The oxide, 
therefore, cannot be penetrated by means of the flame, but must 
be removed either chemically by means of a flux or mechanically 
by means of a paddle. 

Expansion and Contraction. Because of the high heat con- 
ductivity of aluminum, expansion and contraction do not give great 
difficulty owing to localized heating. However, because aluminum 
expands greatly and is very weak when at high temperatures, con- 
traction strains are very likely to produce cracks or checks unless 
the work is allowed to cool evenly and slowly. It is advisable to 
pre-heat aluminum castings to between 300° and 400° F. to aid the 
distribution of the heat and prevent warping. 

Welding Rod. In welding sheet aluminum, such as automobile 
bodies, the welding rod should be clean material of the same alloy 
as the sheets that are being welded. If wire cannot be obtained 
of the same composition as the sheets, narrow strips should be 


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sheared from the sheets themselves and used for a filling material. 
The strips should be sheared about as wide as the sheets are thick. 

For aluminum castings, such as crank cases, a good grade of 
aluminum wire about | inch in diameter should be obtained. Welders 
should not use the cheap solders or very low fusing cast rods that 
are sometimes sold, and for which great claims are made. The 
operator will readily appreciate that when these materials are added 
to the weld they will merely adhere to the sides, because, while the 
filling material will be quite fluid, the edges of the weld will not be at 
a fusing temperature. 

Flux. It is impossible to weld sheet aluminum without the 
use of a good flux to dissolve the oxide and float it to the top as a 
slag. In cast-aluminum work a paddle may be used to accomplish this 
result, but such a device is not practical for sheet work. The 5vx 
may be applied either by dipping the warm welding rod into the 
flux powder or by mixing the flux with water to form a paste and 
applying this to the joints by means of a brush. Care must be taken 
that too much flux is not used, because an excess will produce a 
porous weld and one with a poor surface. After the work has been 
completed the flux should all be washed off with warm water. 

Flame. In order to be sure that an oxidizing flame is not 
being used, it is permissible and advisable to use a flame showing 
a slight excess of acetylene. This flame will also have the advantages 
of being slightly larger in volume than the neutral flame and of lower 
temperature, this last feature being helpful, especially to the new 

Sheet-Aluminum Welding 

Sheet-aluminum work may be handled very similarly to sheet 
steel as regards preparation and allowance for expansion and 

Types of Joints. For light sheets under ^ inch the flange 
weld should be used. The butt joint may be successfully made on 
light sheets by an experienced operator, but there is a great deal 
of danger of burning through and having to fill up holes, which will 
leave a poorly finished weld. 

For sheets above & inch the butt weld is found to be the best, 
and for sheets above J inch the edges should be beveled the same 
as for steel plates. 


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Welding Process. Select the proper size blowpipe and welding 
rod, a good flux, and arrange the work for welding. Start the welding 
by playing the secondary flame of the blowpipe over the parts 
surrounding the weld, to warm them up slightly. If the flux is to 
be applied with a brush, it should be done at this time, because the 
heat will evaporate the water and leave the solid flux evenly dis- 
tributed over the weld. Welding should then be started from £ to 1 
inch from the end — not at the end. The blow pipe should be handled 
about the same as for steel welding, care being taken that the inner 
cone of the flame does not come in contact with the metal. For 
very thin sheet welding it is not necessary to give the circular or 
oscillating motion to the blowpipe; it is merely necessary to move 
it forward in a straight line. 

On the heavier work, however, the same motions should be 
used by the welding operator as are used for steel. The welding 
wire is best held directly in line with the weld and always in contact 
with the metal just ahead of the blowpipe. If the wire is not in con- 
tact with the edges when they become molten, they will be likely 
to curl up or draw away instead of flowing together. After the 
main weld has been completed, the operator should go back and 
weld the short section that was left unwelded at the very beginning. 
After the work has cooled the flux should be removed by washing 
off with warm water. 

Re-Welding. The operator should be careful that the weld is 
completed as he goes along, so that he will not have to go back to 
make repairs or to do re-welding. If it is necessary to go back over 
a weld, cracks or checks are very likely to result because of the 
weak condition of the metal when it is at a fusing temperature. If 
it is necessary to re-weld a certain portion of the joint, the surface 
should be chipped off so as to present a clean surface for the new 
filling material to fuse to. Following the suggestions already made, 
the seam and the surrounding surfaces should be thoroughly pre- 
heated before the welding is started to prevent cracking as much 
as possible. 

After- Treatment If possible, welds in aluminum sheet should 
be reheated evenly to equalize any internal strains. Then, after the 
weld has become cold, it should be hammered to improve the grain 
of the metal. 


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Cast Aluminum Welding 

Aluminum Castings. Most aluminum castings are alloys of 
aluminum, zinc, and copper; the alloy being added to the aluminum 
to give it a higher tensile strength and increase its resistance to 
shock. The welding of cast aluminum is different from that of 
sheet aluminum and resembles in a general way the welding of 
cast iron. Oxidation is taken care of by using flux or by scraping the 
oxide out by means of a paddle. The second method is faster and 
is the one preferred by most operators. 

Paddle. The paddle is made by flattening down the end of a 
J-inch steel rod to a smooth short flat blade about f inch wide. 
The handle may be left straight or bent to suit the operator. The 
paddle should be used only when just below a red heat. If it is 
cold, the molten metal will stick to it, and if it is too hot it will burn 
and the metal will stick to the roughened surfaces. 

Preparation. Sections if over \ inch in thickness should be 
chamfered - before the welding is started. Sections thinner than 
this may be worked without beveling. The old metal may be scraped 
out by means of the paddle in order to give a clean bright surface 
for the new material to be added to. 

Pre-Heating. Because aluminum alloy castings are not very 
ductile and are weak when at a high temperature, expansion and 
contraction must be taken care of. This is handled in the same 
general way as in the case of cast-iron work. The casting should 
be pre-heated either partially or wholly by some slow heating agent, 
such as a gas burner or mild charcoal fire. The pre-heating should 
never be carried to too high a temperature, because of the danger 
of the metal sinking, or caving in. The casting will be sufficiently 
warm for welding when a file or chisel will mark it easily, or when 
a piece of dry pine stick is charred upon being drawn across the 
heated section. 

Welding Process. When a flux is used in welding cast alumi- 
num, the work is carried on in the same general manner as in welding 
cast iron, and the same general precautions regarding the peculiari- 
ties of the metal are to be observed as in welding sheet aluminum. 

If a paddle is used to break the film of oxide and scrape it out of 
the weld, the edges are brought to a state of fusion for a length of 
about 1 or 1§ inches. The paddle is then used to scrape out the weld 


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to make a slight bevel and present clean surfaces for the filling mate- 
rial to be added to. The welding rod is then introduced into this 
groove. The paddle is used continually to work in the filling material, 
scrape off any oxide that forms, and then to smooth off the surface 
of the weld. After a small section of the joint has been completed, 
the casting is turned over, and the weld for this length is smoothed off 
on the underside by means of the blowpipe and paddle. The welding 
is carried on in this manner, section by section, until the entire joint 
is completed. If the weld were completed on the first side and then 
turned over and smoothed its entire length on the underside, cracks 
would develop, and the casting would warp out of shape. 

After-Treatment. When the welding has been completed, the 
casting should be reheated slightly to remove any local strains and 
should then be covered over with asbestos paper to protect it from 
drafts and to allow it to cool very slowly. If the cooling is carried on 
rapidly, or if air currents are allowed to strike the casting, it will very 
likely crack either in the weld or some weak section. 


General Considerations. Because of the high thermal 
conductivity of copper, the heat from the blowpipe is conducted 
back into the work rapidly and is lost to the weld. This necessitates 
the use of a large size welding head or the use of an auxiliary source 
of heat to assist the welding flame in the case of heavy work. When 
at high temperatures, copper is weak in tensile strength the same 
as aluminum. Because of these two factors the effects of expansion 
and contraction must be carefully considered, so that the work will 
not cool too rapidly after the welding has been completed, and will 
not crack at high temperatures. 

Oxidation. Copper oxidizes quite readily, forming an oxide 
which dissolves in the molten metal and changes the structure of 
the weld. The amount of oxide that can be absorbed is very high, 
consequently great care must be exercised to keep the absorption 
at a minimum. Welding rods containing a small percentage of 
phosphorus and suitable fluxes are used to counteract the oxide and 
reduce it as much as possible. 

Welding Rod. For successful copper welding, it is necessary 
to use electrolytic copper containing about one per cent phosphorus, 


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supplied in coils and drawn rods. The cast copper alloy rods that 
are on the market are not satisfactory, because the structure and 
composition will vary even in a single rod to such an extent that a 
homogeneous weld cannot be made. 

Flux. In welding copper the flux is used not only to cleanse 
the weld, but also to protect the metal adjacent to the welding zone 
from the gases of the flame. When welding sheet copper it is advisable 
to make a paste of the flux by adding water and to coat the metal 
about one inch adjacent to the edge of the weld. When this flux is 
melted, it will form a glassy film that will protect the metal from the 
gases of the flame and the air surrounding the work. Additional 
flux is added to the weld as the work progresses, by dipping the 
warm rod into the dry flux, as in welding other materials. 

Flame. It is very important that the neutral flame be 
maintained at all times, and the operator should use great care in 
adjusting his gases, so the flame will not have an excess of acetylene 
nor be oxidizing. Because of the peculiar properties of the metal, 
the gases of the reducing flame are very likely to be absorbed, and 
because of the ease with which the metal oxidizes, oxidation is 
liable to occur if the flame contains an excess of oxygen. 

Preparation. Sheets that are less than J inch in thickness 
may be butted together without beveling. Sheets heavier than 
this should always be beveled, and no attempt should be made 
to depend upon the flame to penetrate the heavier thicknesses. In 
all cases of copper welding, the edges to be joined and the material 
adjacent to the edges should be scraped or filed to present a clean 
surface for the filling material to be added to. 

Welding. The edges of the metal surrounding the weld should 
be raised to a fairly high temperature before the actual welding is 
started. On small pieces and light-weight work, this may be done 
by means of the welding blowpipe, but for heavy work and long 
welds, it is best to do this by means of a gas or oil pre-heating burner. 
After the work has been brought to a high temperature, the welding 
should be started at one end and should be performed as rapidly 
as possible. The welding rod and edges of the weld should reach 
the state of fusion at the same time, so as to prevent adhesion and 
to insure a good weld. This feature is harder to accomplish in welding 
copper than in other metal, because the heat is conducted back into 


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the rod or into the work very rapidly, necessitating very careful 
and skillful manipulation of the blowpipe and rod. The blowpipe 
should be held almost vertical, about the same as in the case of 
cast-iron welding. If held at too great an angle, the molten metal 
will be blown ahead and will adhere to the cold edges of the weld 
in advance of the blowpipe. The inner cone of the flame should 
never come in contact with the metal, but should be held about 
i or £ inch above the surface of the weld to prevent burning the 
metal. The oscillating motion should be carried on about the same 
as in steel welding but a little more rapidly, and should consist of 
smaller circles. The welding rod should be plunged into the molten 
metal all the time and should be continuously moved around or 
stirred, so that it will be thoroughly incorporated and will bring the 
oxide and slag to the surface. The weld should be built up above 
the surface of the sheets, so there will be enough material to allow 
for hammering after the welding has been completed. 

Re-Welding. In case it is necessary to re-weld a portion of the 
joint, it is necessary that the old material be chipped out and new 
material added. 

After-Treatment. After the welding operation has been 
completed, the work should be heated very carefully and evenly 
until it is almost at a bright red heat. The weld should then be 
hammered while hot, so that the strength of the joint will be increased 
as much as possible. After the hammering has been finished, the 
work should be again reheated to a red heat and cooled quickly 
by means of an air blast or chilled by plunging in water. Care must 
be exercised in this operation if the work be a casting having confined, 
or rigid members, so that cracking, or checking, does not occur. 


General Considerations. Brass and bronze are both alloys of 
copper, brass consisting mainly of copper and zinc, and bronze 
of copper and tin. Both brass and bronze are welded in about the 
same general manner as copper, but because of the peculiar properties 
of the alloying metals, zinc and tin, it is necessary that they receive 
certain variations in welding. 

Oxidation. In both brass and bronze, the alloying metal is 
greatly affected by the high temperature of the flame, and the material 


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will be subject to a loss of zinc or tin, unless proper precautions are 
taken. These metals will combine with the oxygen and pass off as 
white vapor, and leave a weld of different composition and color. 

Absorption of Gases. The molten metal in both brass and bronze 
absorbs certain gases very readily, and unless this absorption is 
counteracted, the weld will be spongy and weak. This may be taken 
care of by using a suitable welding rod and flux. 

Welding Rod. Because of the varying composition of brass 
and bronze, and because of the loss of the alloying elements when 
welding, it is practically impossible to produce welds of the same 
color as the original material. When welding brass, a good grade 
of drawn brass will be found most satisfactory, and in the case of 
bronze, a good drawn bronze, such as manganese or Tobin bronze. 
The cast rods that are on the market are not satisfactory, because it is 
quite impossible to cast a rod having the same composition throughout. 

Flux. The flux used for brass and bronze is practically the 
same as that used for copper. It should be applied by dipping the 
warm welding rod into the powder and adding it to the weld in this 
manner. It is not necessary to use as much flux as in welding pure 
copper, and care must be taken that an excess is not used, because the 
weld may become porous. 

Flame. A neutral flame must be maintained at all times for 
the same reasons as explained under copper welding. The blowpipe 
should be held between £ to J inch from the metal. If the flame 
is held too close in the case of bronzes, the concentrated heat will 
cause a segregation or separation of the tin from the copper, and 
it will be practically impossible to again unite these elements. 

Preparation. The edges of the metal for a thickness of less 
than J inch may be merely butted together and welded, while for 
metals above this thickness the edges should be beveled or cham- 
fered, so as to allow penetration of the flame and insure a good weld. 

Welding. Because of the high conductivity of these materials, 
it is best that they be pre-heated to bring them to a suitable condition 
for rapid welding. Care must be taken when pre-heating bronze 
that it does not get too hot, because it is weak at high temperatures 
and is liable to break or* crack under its own weight. The 
welding is carried on in about the same manner as for copper, and 
the blowpipe is handled in practically the same way. The welding 


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rod should be in contact with the edges of the metal at all times, 
and the blowpipe should be played constantly on both the rod and 
the edges of the metal to keep them at the same temperature in order 
that adhesion may be prevented. 

Re-Welding. Re- welding should be avoided, but if it is 
absolutely necessary to re-weld the work, the section should be 
chipped out, and new material added, as in the case of copper. 

After-Treatment. Both brass and bronze should be annealed 
after welding by reheating evenly, and then allowed to cool slowly. 
Brass may be improved by hammering before the final annealing. 
Brass of low zinc content, i.e., red brass, should be hammered 
while hot, while brass of high zinc content, i.e., yellow brass, 
should be hammered cold. 

Cutting In Automobile Repairs. The oxy-acetylene cutting 
blowpipe finds considerable application in the automobile repair 
shop for beveling the ends of shafts 
and other pieces of work preparatory 

Fig. 80. Beveling Round Shaft for Welding. Fig. 81. Beveling End of Heavy 

The other piece is on the table Square Shaft for Welding 

to welding, Figs. 80 and 81, cutting reinforcing plates out of large 
sheets for frame repairs, altering chassis, etc., Fig. 82. The cutting 


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blowpipe is capable of doing this work cheaply and quickly, two 
necessary factors for the successful first-class repair shop. 

Principle of Cutting with Oxygen. At ordinary temperatures, 
steel oxidizes in the air, forming what is commonly called "rust". 
At a white heat it will oxidize more rapidly, as is seen in the black- 
smith shop when pieces are brought to a very high temperature. 
When steel is heated to a red heat, and 
a stream of pure oxygen is directed on 
it, the oxidation takes place more rap- 
idly and more violently and is restricted 
to the locality upon which the stream 
of oxygen is played. This localized oxi- 
dation is the basis upon which the oxy- 
acetylene cutting blowpipe operates. 

Metals That Can Be Cut. Steel and 
wrought iron are the only metals that 
can be cut successfully by means of 
the oxygen jet. Although cast iron, cop- 
per, brass, bronze, aluminum, etc., oxi- 
dize easily, nevertheless they cannot 
be cut. 

When the oxygen combines with 
the iron, heat is generated. This heat ~ QO ^ 44 . ■ . . . ™ A 

' ° Fig. 82. Cutting Reinforcing Plate 

of formation, with the aid of the heat ° utof FrYmeRe^ir for 

supplied by the pre-heating flames of 

the blowpipe, brings the oxide to a molten condition. The molten 
oxide either flows or is blown out of the cut and leaves a fresh 
thoroughly heated line through the metal for the further action 
of the cutting oxygen. In the case of steel and wrought iron, the 
oxide melts at a much lower temperature than the material being 
cut and therefore blows out without melting the surface of the 
material. In the cases of cast iron and certain alloy steels, the 
melting temperature of the oxide is as high and in some cases 
higher than that of the metal, and therefore melts the edges or 
freezes in the kurf and so hinders the cutting. Also, in the case 
of some of these materials, the heat of formation produced by the 
combination of the oxygen with the metal is not sufficient to carry 
the cut through the thickness of the work. 


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Necessary Cutting Apparatus. A complete cutting station, 

Fig. 83, consists of the following apparatus: 

Cutting blowpipe with set of cutting nozzles 
Oxygen cutting regulator with two gages 
• Acetylene regulator with one or two gages 
Adapter for acetylene cylinder 
One length high-pressure rubber hose for acetylene 
One length copper armoured hose for oxygen 
Darkened spectacles, wrenches, hose clamps, etc. 

Cutting Blowpipe. 

In the cutting blowpipe, 
Fig. 9, page 9, there 
are usually six small 
oxy-acety lene flames sur- 
rounding a center orifice 
through which pure oxy- 
gen is directed. The six 
heating jets are used 
only for the purpose of 
bringing the edge of the 
material to a tempera- 
ture at which the jet of 
pure oxygen will unite 
rapidly with the steel, 
as explained above. 

Cutting Nozzle. 
There are usually four 
sizes of cutting nozzles 
furnished for handling 
work of various thick- 
nesses, from very thin 
plate up to material 14 
and 16 inches thick. 
Besides these, some 
manufacturers also f ur- 
lere * nish what is known as 

Courtesy of Oxwdd-Acetylent Company, Chicago a "rivet Cutting nOZZle". 

This is a thin flat nozzle that can be laid against the sheet, allowing, 
the rivet head to be cut off close to the sheet. 


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Working Pressure. The necessary pressures of the gas that are 
required by the different sizes of cutting nozzles and for the different 
thicknesses of material are given by the manufacturers. It is very 
important that the operator use these pressures instead of higher 
pressures because of the increased amount of oxygen used and the 
consequent high cost of operation, also because the cut will not be 
smooth if too much oxygen is used. 

Care of Blowpipe. If the blowpipe is handled properly there 
will be very little deterioration. It should only be necessary to 
clean the replaceable and working parts, repack the valves, and 
occasionally ream out and true up the nozzles. Care should be taken 
that the orifices of the nozzles do not become enlarged by reaming, 
because the heating jets will be made thicker and shorter and the 
cutting jet will spread rather than leave the blowpipe as a long 
thin stream. 

The blowpipe may be cleaned the same as the welding blow- 
pipe by removing both the acetylene and oxygen hose and connecting 
the nozzle to the oxygen hose, Fig. 16, page 18, and turning on the 
oxygen to a pressure of about 20 pounds per square inch, having 
first the cutting oxygen valve open, then the acetylene needle valve, 
and lastly the oxygen needle valve. This will allow the large particles 
to be blown out of the larger passages before they have a chance 
to clog up the smaller passages. 

Regulators. The cutting regulator, in principle, is the same as 
that described on page 20, but in size it is much larger than the 
welding regulator and is capable of both a higher delivery pressure 
and a greater volume. 

The acetylene regulator is the same as is used in the welding 
equipment, and described on page 20. 

Care of Apparatus. The blowpipe, regulators, and hose should 
receive the same care and attention as is explained for the welding 
apparatus on pages 18 to 21. 

Instructions for Connecting Apparatus. The regulators and the 
blowpipe are connected up in the same manner as the welding 
apparatus, and therefore the operator is referred to pages 22 to 23 
for instructions. 

How To Light the Blowpipe. (1) Take the blowpipe in hand 
and open the oxygen cutting valve fully. 

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(2) Turn the oxygen pressure-adjusting screw to the right 
until the required pressure for the work to be done shows on the 
low-pressure gage. (See the maker's chart for the correct pressure.) 

(3) Close the oxygen cutting valve. 

(4) Open the acetylene needle valve fully. 

(5) Turn the acetylene pressure-adjusting screw to the right 
until a good jet of acetylene issues from the heating orifices. In 
the case of pressure blowpipes, until the required pressure for the 
thickness to be cut shows on the low-pressure gage. (See the maker's 
chart for the correct pressure.) 

6. Open the oxygen needle valve one-quarter turn and light 
the blowpipe by means of the pyro-lighter that is usually furnished. 

Note — A back-fire might occur if there is not enough acetylene being 
supplied. If this occurs increase the acetylene supply by turning the acetylene 
pressure-adjusting screw farther to the right. 

7. Adjust the acetylene pressure-adjusting screw to give a 
slight excess of acetylene to the flame. 

8. Adjust the acetylene needle valve to give a neutral flame 
(see under Flame Regulation, page 25) when the cutting oxygen 
valve is open. 

To Shut off the Blowpipe. In the case of the injector type of 
blowpipe, first close the acetylene needle valve and then the oxygen 
needle valve. 

In the case of pressure blowpipes, first close the oxygen needle 
valve and then the acetylene needle valve. 

To Cut. With the cutting valve closed apply the heating flames 
to the edge of the metal, keeping the nozzle at such a distance that 
the small flames barely touch the metal. As soon as the metal 
becomes heated to a cherry red, open the cutting valve, raise the 
blowpipe slightly to increase the distance between the nozzle and 
metal, and then move it along the surface as fast as a distinct and 
and clear kurf can be secured. The blowpipe should be held at a 
constant distance from the work. It should travel away from the 
operator in order that he may watch the cut advance. 

Back-Firing. Occasionally, particles of molten metal will 
impinge on the nozzle of the blowpipe, or the operator will allow 
the nozzle to touch the surface of the metal, and the blowpipe will 
back-fire. When this occurs, first close the acetylene needle valve 


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and allow oxygen to clear the passage, then open the acetylene 
needle valve fully and relight. If the back-firing continues, close 
both the acetylene and oxygen needle valves, cool the blowpipe by 
plunging in water and relight. Other causes of back-firing are 
loose internal and external nozzles or dirt on the nozzle seat. These 
can be eliminated by tightening the nozzles and cleaning the seat. 
These back-fires are usually only a series of pops or sharp reports, 
and, as a rule, will not extinguish the flame. 

Notes on Cutting. Heating Flames. The heating flames 
should be small to produce smooth cutting. If the flames are too 
small, the blowpipe is liable to back-fire. If they are large, the top 
edges of the cut will melt and produce a rough cut. 

Speed of Cutting. The speed of the blow r pipe travel should be 
slow enough to allow the oxygen jet to penetrate yet not so slow 
that the oxygen will be wasted. 

Restarting Cut. If the blowpipe travels too fast, and the cut 
is "lost", it is necessary to shut off the cutting oxygen and apply the 
heating flames to the point of stopping until the metal is hot enough 
to start the cut again. 

To Cut Round Shafts, Etc. The cutting of round pieces will 
be made easier if the surface of the work is first chipped with a chisel. 
This will present a good edge for the cutting blowpipe to bite on. 

To Pierce Holes. When piercing holes, a high oxygen pressure 
is necessary, and the metal must be brought to fusion before the 
cutting oxygen is employed. The blowpipe is held at a slight angle so 
the sparks will be blown out of the hole and away from the blowpipe. 

Cutting Dirty and Poor Material. If there is considerable rust, 
scale, paint, etc., on the surface, the cutting will be interfered with 
by small particles flying against the end of the nozzle and perhaps 
causing back-firing. To overcome this, the heating flames may be 
made longer, allowing the blowpipe to be held farther away from 
the surface, or the scale or paint may be removed by first passing 
the flame over the line of cutting before the cutting is started. 


Different Methods. Formerly, lead burning, or lead welding, 
was confined to garages and service stations that catered to the electric 
automobile only, but since the introduction of electric lighting and 


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starting batteries for gasoline automobiles, lead burning has become 
one of the works of the repair man in all garages. It is therefore 
important that the repair man have a sufficient knowledge of this 
class of work to enable him to handle any work of this nature that 
may happen to come into his shop. 

Up to the time of the recent development of a very small oxy- 
acetylene blowpipe for lead-burning work, the hydrogen air burner 
was used by most lead burners. The oxy-acetylene blowpipe, how- 

Fig. 84. Oxy-Acetylene Lead Burning Apparatus 
Courtesy of Oxweld Acetylene Company, Chicago 

ever, is rapidly supplanting the old method and, as a matter of fact, 
within two years it has become universally accepted as being far 
superior to the old method in handiness of operation, speed, and 
consequent economy, and has been adopted by the large battery 
makers in both their factories and service stations. 

When an operator accustomed to the old flame tries the oxy- 
acetylene blowpipe, he is very likely to discredit it at first and claim 
that it is not satisfactory. However, every operator who gives the 
oxy-acetylene lead-burning blowpipe • a fair trial and uses it in 
accordance with the methods recommended by the manufacturers 


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of the apparatus must acknowledge it as being superior to any 
method he has ever used. Its advantages are emphasized even more 
emphatically if he returns to the old, slower, and more costly methods. 
Lead-Burning Apparatus. A complete lead-burning station 
for use with oxygen and acetylene, Fig. 84, consists of the following 

Lead-burning blowpipe with set of tips 

Oxygen regulator with low-pressure gage 

Acetylene regulator with low-pressure gage 

Adapter for acetylene cylinder 


Two lengths of high-pressure hose to connect regulators to valve block 

Two lengths of b oq\\ hose to connect blowpipe to valve block 

Lead-Burning Blowpipe. To make the blowpipe as light in 
weight and as handy as possible there are no large valves. Instead, 
a valve block is furnished for regulating the gases, which may be 
attached to a bench or a wall. In order to make minor or finer 
adjustments of the flame, and to allow various size tips to be used 
on the blowpipe and still maintain a perfect flame, an adjustable 
injector is provided at the top of the blowpipe within reach of the 
operator's fingers. 

Tips. There are about five sizes of tips supplied for use on 
different thicknesses and various classes of work, each giving its 
own special size flame. The oxygen consumption of the various 
size tips ranges from § to 6 cubic feet per hour. For storage-battery 
work the average consumption is about 2 cubic feet per hour. 

Regulators. The regulators supplied with lead-burning apparatus 
operate on the same principle as the regulator described on page 19, 
the only difference being that they are of smaller size and especially 
adapted to small flames. 

Operation of Lead-Burning Apparatus. The apparatus is 
connected in the same general manner as the welding apparatus 
for which instructions are given on pages 22 to 26. The needle 
valves on the valve block are used to obtain approximate adjust- 
ment of the flame, and then the small thumb-nut on the blowpipe 
is used to make the finer adjustment. The pressure-adjusting 
screws should be set to give pressures of about 10 pounds per 
square inch for the oxygen, and 2 pounds per square inch for 
the acetylene. 


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The blowpipe, regulators, hose, etc., should receive the same care 
and attention as the welding apparatus and for which suggestions 
are given on pages 18 to 21. 

Lead-Burning Process. The oxy-acetylene blowpipe should be 
handled in such a manner that the flame strikes Ihe work perpen- 
dicularly. If the blowpipe is used on a slant, the inner cone will 
not bring the work to the fusing temperature as rapidly as if held 
vertically, and the secondary flame, or outer envelope, will be very 
likely to heat the surrounding metal to such a temperature that it 
will give way and break under its own weight. When working with 

the oxy-acetylene flame on stor- 
age batteries and the like, the 
operator should do the burning 
quickly. He should bring the 
flame down to the work, fuse the 
metal, add the necessary burn- 
ing bar, or filling wire, smooth 
off the work, and remove the 
flame, all as rapidly as possible. 
Burning Terminal Groups. 
When burning plates to terminal 
bars, a small flame should be 
used, and the work should be 
held in a fixture, as show T n in 
Fig. 85. The small ends on the 
,,.„,., ^, plates should extend up into the 

rig. 80. Assembling Terminal Groups 

terminal bar slots about two- 
thirds of the way. The burning should be carried on by first fusing 
the ends of the plates to the bottom of the slots, then filling up the 
rest of the slot by adding lead from a coil of wire or a burning bar. 
After the several plates have been burned on in this way, the flame 
should be moved perpendicularly over the surface to smooth it off 
and leave a nice finish. The flame should not be held flat against 
the work. It will take longer to smooth off the work, and it will 
not have nearly as neat an appearance if the flame is used flat. 

Burning-On Connecting Links. The terminal poles should 
extend up into the links about one-third of the way. The flame 
should be brought down into the hole until the inner cone almost 

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touches the top of the pole, and the pole fused and united with the 
bottom of the link as quickly as possible. After a good union has 
been secured in this manner, the burning bar should be introduced 
and the rest of the cavity filled up, Fig. 86. When working on links 
and poles it is advisable to do only part of one pole, move to another 
for a few minutes, and then come back to the first for a few minutes. 
This will allow the work to cool off slightly and will prevent breaking 
down or melting away. When burning this class of work, especially 
if the lead is old and pitted with dirt and cut by acid, it is advisable 
to increase the supply of oxygen 
and use an oxidizing flame 
when working down in the 
pocket. This will burn out any 
dirt and will prevent the blow- 
pipe from puffing out when it is 
burning in the rare atmosphere 
that exists in the pocket. 

Forms or Molds. Small steel 
frames, or molds, are found very 
convenient, especially when 
working on terminal links. 
These molds are shaped to con- 
form to the work and are placed 
around it while burning. They 
are a great help in preventing the _ . oa ^ . . _ A . T . , 

& v ^ ft Fig. 86. Burmng-On Connecting Links 

corners of the work from break- 
ing down and melting away and, in this manner, relieve some of 
the tediousness of the work and allow the operator to work under less 
strain, and permit the work to be done by men who are not skilled 
lead burners, but who have occasional work of this sort to do. 


Methods. Old Process. Up to within the last few years 
the methods used for removing the carbon from gas-engine cyl- 
inders were very impractical and unsatisfactory. To do this work 
meant the dismantling of the motor, the removal of all the parts, 
and the scraping of the cylinder walls by hand. Because this 

95 Digitized by G00gle 


operation necessitated a great deal of work it was not done, in most 
cases, until the carbon deposit became very he^vy. 

Oxygen Process. The introduction of the inexpensive process 
of removing the carbon by burning it out by means of pure oxygen 
has replaced the old methods and they are no longer used. This 
new process is so simple, necessitates so little work, can be done so 
quickly and cheaply, that it can be employed every few months and, 
in that way, keep the cylinders free from carbon. 

Carbon-Removing Apparatus. Complete apparatus for remov- 
ing carbon by means of oxygen, Fig. 87, consists of the following: 

Carbon-removing handle with flexible tube 
Oxygen regulator with low-pressure gage 
One length of high-pressure rubber hose 

It will be seen from this list that all that 
is necessary for a garage to have in addition 
to its welding equipment is the carbon- 
removing handle with a flexible tube. 

Burning Out Carbon. Shut off the gas- 
oline at the tank or just in front of the 
carburetor and allow the engine to run until 
it has sucked the gasoline out of the lines. 
Remove the valve caps and spark plugs 
from all the cylinders. 

Turn the engine over by hand until 
the first piston is at the upper end of its 
stroke and both its valves are closed. Intro- 
duce a small quantity of kerosene into the 
cylinder head by means of an oil can or a 
Fig. 87. Carbon-Removing piece of saturated waste. Light the kero- 
sene in the cylinder, introduce the end of 
the flexible tube into the cylinder and allow the oxygen to play 
on the carbon at a pressure of about 5 pounds per square inch. 
The carbon deposit will catch fire and will continue to burn as 
long as there is carbon present. Of course, if the carbon is depos- 
ited in patches it will be necessary, after one patch has been 
removed, to start another by means of kerosene. 

After the first cylinder has been thoroughly cleaned, turn the 
engine over by hand until the piston of the second cylinder is at 


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its upper stroke with its valves closed, and then proceed to remove 
the carbon from this cylinder in the same manner. 

After all the cylinders have been thoroughly cleaned, clean the 
valve caps and spark plugs by scraping or by burning off the carbon 
and then replace them in the engine. 

Notes on Carbon Burning. Before burning out the carbon be 
sure that there is no chance of gasoline being present which might 
cause back-firing into the intake manifold. 

The oxygen pressure should not be too high. Only enough oxygen 
should be supplied to keep the carbon kindled. Too much pressure 
will waste oxygen and increase the cost of burning out the carbon. 

Too much kerosene must not be used, because there is a chance 
of the operator burning his hands with the sudden burst of flame 
that might result. 


Pressed-Steel Parts, All pressed-steel parts of automobiles, 
such as frames, bodies, fenders, axle housings, tubing, etc., should 
be welded, using a pure iron welding wire for a filling material. 

Frames. Almost all frame repairs necessitate a certain amount 
of dismantling of other parts. The extent of the dismantling depends 
upon the location of the proposed weld. If the work is to be done 
under the body, it is best to remove the car body. This is not 
absolutely necessary, however, because the work can be done by 
merely jacking up the body several inches to give enough room to 
do the work, and protect the body from the heat of the welding 
flame. If the weld is to be done close to the radiator, this should 
be removed so that the solder will not be melted out, Fig. 88. If 
the weld is about 12 inches from the radiator, the solder can be 
protected by placing sheet asbestos over the radiator. In this 
connection it is well to remind the operator that it is always advisable 
to cover the parts of the car near the welding with sheet asbestos 
to protect them from any possibility of the flame or heat getting 
too close. 

Jacks should be placed under the frame and the frame brought 
into alignment before the welding is started; the jacks should not 
be removed until the weld has been completed and has become 
thoroughly cooled. 


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It is always advisable to bevel the work by chipping. In the 
case of frames of light-weight pleasure cars this may be dispensed 
with if the operator is careful to penetrate through the thickness 
of the material. All paint, dirt, and grease must be scraped off 
next to the weld from both the inside and outside of the frame 
before the welding is commenced, to prevent dirt from being 
incorporated in the weld. 

A reinforcing plate should be prepared about the same thickness 
as the frame, as wide as the frame is high, and about three times 

Fig. 88. Radiator Is Removed if Welding Flame Is Near It 

as long as it is wide. This may be cut out of sheet steel by means 
of the cutting blowpipe, Fig. 82, page 77, or by means of a hack saw. 
The blowpipe is the quickest and easiest method, especially for 
cutting plates for curved frames such as are used on pleasure cars. 
The weld will look better if the reinforcing plate is welded on the 
inside of the frame, but in some cases that is impossible without a 
great deal of extra dismantling. It is then allowable to weld it on 
the outside. 

The welding should start at the lower end of the frame and 
move upward as explained under Vertical Welding, page 31. The 

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two flanges of the channel should then be welded, starting at the 
corner and moving toward the edge. When welding the lower 

Fig. 89. Badly Bent Frame 

Fig. 90. Frame after Heating with Welding Flame and Straightening 

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flange, the work should be carried on as explained under Overhead 
Welding, page 31. After the frame has been welded, the reinforcing 
plate should be welded on by welding the horizontal edges first 
and the ends last. 

The weld will be materially strengthened if it is hammered 
during the process of welding, as explained under Hammering, 
page 46. 

The oxy-acetylene blowpipe is also very valuable in straightening 

frames that have become bent in 
accidents. A frame of this sort 
is shown before and after straight- 
ening in Figs. 89 and 90. 

Bodies and Fenders. Bodies 
and fenders that have been torn 
can be successfully welded if the 
operator uses his best efforts and 
is careful. 

Fenders, as a rule, do not 
present very much difficulty be- 
cause the break usually extends 
to the edge. It is advisable to 
pack wet asbestos along both 
sides of the weld to prevent buck- 
ling as much as possible, Fig. 91. 
The wet asbestos will absorb the 
^lonTw 1 !^ heat and will not allow it to be 

of LiK ht sheet. conducted back into the sheet. 

Bodies should be welded in a similar manner when they are 
torn. If possible, it is advisable to bend the edges outward slightly 
before welding. Then, as the weld is cooling, hammer it flat to 
compensate for the contraction that takes place. 

If a patch must be welded in, it should be prepared either 
round or oval, or should have rounded corners of large radii. 
The patch should be dished to compensate for the contraction 
thai'- *vill take place when the work cools. The hole in the body 
and thj patch should be trimmed so as to fit well. W r heii 
the pafch is ready, it should be tacked in place. The welding 
should be carried on as quickly as possible. After the weld has 


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been completed, the flame should be played on it to heat it evenly. 
As the weld starts to cool, the center of the patch should be heated 

Fig. 92. Broken Front Axle 

Fig. 93. Welded Front Axle 

Fig. 94. Crankshaft in Crankshaft Jig Table for Welding 

slightly so that it will stretch easily and compensate for the coi* 
traction taking place in the weld. 




Springs. The welding of springs should not be attempted 
except for emergency repairs to allow the car to be used until a new 
spring can be obtained. A steel \\ v elding rod of low-carbon content 

Fig. 95. Pro-Heating Crankshaft with ('.as Fig. 90. Welding Crankshaft. Note that 

Burner the Pro-Heating Burner la Used to 

Assist the Welding Flame 

should be used for filling material. No attempt should be made 
to re-temper the spring, because the average garage is not equipped 
to handle work of that nature and, consequently, the spring is very 

Fig. 97. Welded Crankshaft 

likely to be worse if a poor job of tempering is done than if tempering 
is not attempted. It is well to pack wet asbestos around the spring 
next to the weld to prevent the heat being conducted back into the 
rest of the spring. 


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Shafts and Axles. Shafts and axles are alloys of nickel, nickel 
and chromium, or chromium and vanadium. It is desirable to have 
the filling material of the same composition as the shaft or axle, 
but this is practically impossible. The most suitable welding rod 

Fiji. 98. Broken Malleable-Iron Rear-Axle Housing 

that can be obtained for this work is one containing about 3.50 
per cent nickel, or one containing about 0.20 per cent vanadium and 
0.12 per cent chromium. This latter steel is more difficult to handle 
under the welding flame, so that most welders prefer the 3.50 per 
cent nickel rod. 

Square shafts, Figs. 92 and 93, and round shafts, Fig. 80, page 
76, should both be beveled by means of the cutting blowpipe or by 
grinding, and should then be placed in alignment or in suitable 
jigs, Fig. 94. A gas or oil pre-heating burner should then be directed 

Fig 99. Repaired Malleable-Iron Rear-Axle Housing 

on the point of welding, Fig. 95, and the work heated to a red heat 
before welding is started. The welding should then be carried on, 
Fig. 96, according to the instructions given under Welding Heavy 
Sections, page 58. After the welding has been completed the work 
should be reheated and any straightening done that is necessary. 


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The weld should then be heated up evenly, covered over with sheet 
asbestos, and allowed to cool slowly. The finished weld is shown 
in Fig. 97. 

Axle Housings. If the housing is of pressed steel, it will not 
present any particular difficulty to the welder, except that he will 
have to take care that it does not get out of alignment. A pure iron 
welding wire should be used, and the work should be prepared and 
carried on as explained under Light Sheet-Steel Welding, pages 
46 to 50 

If the housing is of malleable iron, Figs. 98 and 99, it should 
be beveled, placed in alignment, and then brazed, using Tobin bronze 

for a filling material as 
explained under Malle- 
able-Iron Welding, page 
67. The work may be 
pre-heated slightly to re- 
lieve the effect of expan- 
sion and contraction, but 
must not be heated above a 
dark red. The operator 
must be very careful to 
not bring the malleable 
iron at the weld to too 
high a heat or its mal- 
leable properties will be 
destroyed and the hous- 
ing will be weak. 

Manifolds. Pressed- 
steel manifolds should be 

Fig. 100. Welding Broken Flange on Manifold wek , ed according ^ fa 

directions given under Light Sheet-Steel Welding, pages 46 to 50. 
Cast-iron manifolds, as a rule, have only simple breaks to be 
repaired, such as broken flanges, Fig. 100. These should be beveled, 
and the parts clamped to a flat surface to keep them straight. They 
should then be pre-heated in the vicinity of the weld by means of 
the welding blowpipe before the welding is started. After the weld 
is completed they should be reheated evenly and then covered 
over and allowed to cool slowly. 


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Engine Cylinders. If the water jacket is cracked, the crack 
should be chipped out and the surface of the casting next to the 
groove should be cleaned by scraping. If the cylinder is cracked in 

Fig. 101. Water Jacket Cut Away to Allow for Welding Cylinder Wall 

the head end, it will be necessary to cut away a section of the water 
jacket by drilling or sawing, Fig. 101. After the cylinder head has 
been welded, the water-jacket section can be welded back into place, 
Fig. 102. Sometimes it is quite difficult to detect how far the crack 
really extends, therefore, care must be taken to be sure that it is 
chipped out its entire length. 

All of the plugs and other fittings must be removed from the 
cylinders before pre-heating. The cylinders should be placed in 

Pig. 102. Cylinder Wall Welded and Section of Watcr-Jacket Replaced 

the pre-heating fire with the open end of the cylinder upward, 
Fig. 103. They may be placed on a slant if the crack is on the side 
of the water jacket; but they must be in such a position so there 


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will be no chance for dead air to remain in them. If this precaution 
is not taken, the cylinder walls are very likely to crack. 

The welding should be carried on according to the directions 
given under Cast-iron Welding, pages 59 to 67. The cylinders 
must be left in the charcoal fire all during the welding. It is even 
advisable to keep the top of the fire covered over and to weld through 
a hole in the asbestos paper, Fig. 103, to prevent air currents from 
striking the cylinder while it is hot. After the welding has been 

fig. 103. Welding Cylinders and Preparing Pre-Heating Fire for Cylinders 

completed, the fire should be started up enough to heat the entire 
casting evenly, and should then be covered over and allowed to die 
out. The cylinder must not be removed until it has become cold 
enough to be handled with bare hands. 

Protection for Machined Surfaces. The finish in the bore of the 
cylinder will be affected by the heating if some means is not used 
to protect it. The best protection that can be used is to coat it and 
other machined surfaces with flaked graphite and oil. This can 
be made into a paste and painted on, or the surfaces can be oiled 


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Fig. 104. Water Jacket Plugged and Welds Being Tested 
with Gasoline 

and the graphite dusted on. The latter method is really the best 
if carefully applied. The graphite must be coarse; the fine flake 
will not do. 

Testing Welded Cyl- 
inders. There are sev- 
eral ways of testing 
welded cylinders. The 
two most generally used 
are by water pressure 
and by gasoline. In the 
first method, the water 
jacket is tightly plugged, 
filled with water, and 
then subjected to pres- 
sure by means of a hand 
pump. The method of 
using gasoline is simpler 
and quicker. The water 
jacket is plugged and 
filled with gasoline, Fig. 
104. If there are any 
cracks or leaks the gas- 
oline will work its way 
through and will spread 
out over the surface sur- 
rounding the crack or 

Crankcases and 
Transmission Cases. It 
is usually necessary to 
remove the case from the 
car. But, if the arm is 
broken some distance 
from the main case, it 
may be welded while in 
position, as shown in Fig. 105. When welding in this manner, it is 
necessary to cover the parts near the welding with asbestos sheets 
to protect them from the flame of the blowpipe. The arm should be 

Fig. 105. Welding Arm of Crankcase without Dismantling 


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pre-heated slightly by means of the welding blowpipe before the 
actual welding is started, and, after the welding has been completed, 

it should be reheated to relieve 
any internal strains, and muSt 
then be covered over to allow it 
to cool slowly. 

Some operators spend a great 
deal of time trying to keep the 
bearing of the case in line, and 
while doing this they allow the 
rest of the case to twist, so that 
it is necessary to take a machine 
cut off the edges in order that 
they may fit the other half of the 

Fig ' ^M^Be nSaLES aiTo?™ CaTO ~~ case * ** ls muc ^ better to keep 

the edges true and dress up the 
bearings, because it is quite likely that the bearings will have to be 
trued up anyway. The case should be clamped flat against two 
straightedges, but not too tight, or the case might crack from the 

strains produced when heat is 
applied. The case should be 
placed on the welding table in 
such a position that the welder 
can work on the outside and 
smooth off the inside without 
having to disturb its position. 

Fig. 107. Lower Half of Crankcaae with Piece The most Satisfactory 

Broken Out— Must Be Entirely Pre-Heated ... 

method of pre-heating is to place 

Fig. 108. Upper Half of Crankcaae with Piece Broken Out and Missing 

a gas burner under the case and let it burn vrithout an air blast. If an 
air blast is turned on, the case is liable to become overheated and 


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cave in. In fact, unless there are holes to allow some of the heat 
to escape, the case is liable to become overheated with only the 
soft gas flame. If the case is broken at one end, as shown in Fig. 108, 
it is only necessary to heat the one end; but it is very necessary to 
heat both sides of that end to prevent warping. If like the case 
shown in Figs. 106 or 107, it is best to heat the entire case. This 
can best be done by using two gas burners so that the heat will 
surely spread. 

If the case is cracked or a piece is broken off, the welding should 
start at the inner end of the crack and move toward the edge or corner. 
The welding should be carried on 
as directed under Cast Aluminum 
Welding, page 71. 

If a piece has been broken 
out and lost necessitating building 

Fig. 109. Sheet-Iron Form to Back Up Section to Be Welded-In 

up a section of the casting, Fig. 108, it is necessary to back-up the 
work by means of a piece of sheet iron bent to the required shape, 
Fig. 109. The welding should be started at one edge and should 
move across the space in a line parallel to the edge. When the 
added material gets almost to the opposite edge, the welding should 
stop, the edge of the case and the edge of the new added section 
should be cleaned, and then the weld completed in the same manner 
as for welding up a crack, Fig. 110, as outlined above. 


The cost of welding varies within wide limits for the different 
metals and the different classes of work. It is, therefore, not possible 
to give cost tables that will apply to all work. The costs given in 
Tables II and III are for steel work under fair conditions. 

Measuring Oxygen Consumption. Oxygen is supplied 
compressed to 1800 pounds per square inch, in cylinders containing 


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Welding Cost Table 


of Metal 


(ft. per hr.) 


per Linear Foot 

(cu. ft.) 


per Linear Foot 

(cu. ft.) 

per Linear Foot 

Labor 46c 

Oxygen 2c 

Acetylene.. 2|c 





$ .024 














































Cutting Cost Table 


of Metal 


(ft. per hr.) 


per Linear Foot 

(cu. ft.) 

per Linear Foot 

(cu. ft.) 

per Linear Foot 

Labor 45c 

Oxygen 2c 

Acetylene.. 2Jc 





$ .014 



















































Factors for Correcting; Oxygen Volumes 

Deg. F. 


Deg. F. 


Deg. F. 













1.030 1 






1.040 \ 












1.061 , 


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100 and 200 cubic feet. The amount of oxygen in a cylinder can 
be measured quite accurately by means of the high-pressure gage 
on the regulator. Most of these gages are supplied with two rows 

Fig. 110. Upper Half of Crankcase with Section Built-in 

of figures on the dial, Fig. 111. The outer circle gives the pressure 
in the cylinder in pounds per square inch, and the other circle gives 
the per cent of oxygen remaining in the cylinder. The latter set of 
numbers makes the calculation very easy: e.g., if a 100-cubic foot 
cylinder is being used and the gage hand indicates 73, there is 73 

Fig. HI. Dial of High-Pressure Gage of Oxygen Regulator 

cubic feet of oxygen in the cylinder. If a 200-cubic foot cylinder is 
being used, there is 200X0.73 = 146 cubic feet in the cylinder. 
The amount of oxygen indicated by the gage reading is more or less 
approximate and depends upon the temperature of the oxygen in the 


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cylinder. The correction factors given in Table IV should be used 
to determine the volume of the oxygen at "standard temperature", 
60° F., if an accurate measurement is required, e.g., if in the case 
given above the temperature is 50° F., then the real volume at 
standard temperature would be 146X1.020=148.9 cubic feet. 

Measuring Acetylene Consumption. The amount of acetylene 
in a cylinder cannot be determined by means of the high-pressure 
gage. All the high-pressure gage can be used for, in the case of 
acetylene, is to indicate very roughly the amount of acetylene in 
the cylinder. There is only one method that can be used to determine 
the amount of acetylene used, and that is to weigh the cylinder. 
Each pound by weight of acetylene is equal to 14.5 cubic feet. There- 
fore, to determine the amount of acetylene used on a certain job, it is 
necessary to weigh the cylinder before and after welding and 
calculate the volume cf ?cetylene used from the difference in weight, 
e.g., if the cylinder weighs 217 pounds before welding and 207$ 
pounds after welding, then (21 7 - 207$) X 14.5 = 9$ X 14.5 = 137.7 
cubic feet. 


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Courtesy of Gould and Eberhardt, Newark, New Jersey 

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Importance of Shop Equipment. The average garage or repair 
shop should be equipped to do any repair job which comes into the 
shop. Of course, the demands in different districts vary somewhat, 
but a study of the requirements will guide the management in the 
installation of the equipment necessary. This article is intended to 
cover the more common bench operations and the operations per- 
formed on the various machines which are most necessary. In the 
article on Building, 
Equipping, and Running 
a Public Garage, other 
suggestions as to equip- 
ment of tools and ma- 
chines are given. In still 
another article on Oxy- 
Acetylene Welding 
Practice, practical in- 
structions for welding 
various metals and var- 
ious parts of an automo- 
bile are given. 


Work Bench Design. 

As a large portion of the 

repair work in a shop is 

bench work, the height, 

width, and equipment of 

the work bench should be 

carefully considered. The machinist's bench at which hand work is 

ordinarily performed should be of substantial character, about 2 feet 

10 inches from the floor and 2 feet 3 inches wide, Fig. 1 . For the sake 

of economy it is usual to have a 2J- or 3-inch plank at the front to 

which the vises are fastened and on which all the heavy work is 

Fig. 1. Work Bench 

on and Sharpe Manufad 

Providence, Rhode Island 

Courtesy of Brown and Sharpe Manufacturing Company, 

%ce, Rhc ' 


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done, while the rear of the bench is made from 1-inch lumber. Maple 
and birch are preferred as materials for a bench, although ash makes 
a very good substitute. 

Work Vises. In order, that work may be held rigidly for the 
performance of hand operations, the machinist uses what is termed 
a vise. They are made in a great variety of forms and sizes, but all 
consist essentially of a fixed jaw, a movable jaw, a screw, a nut fas- 
tened to the fixed jaw, and a handle by which the screw is turned 
in the nut and the movable jaw brought into position. The sec- 
tional view, Fig. 2, shows these parts clearly and also a device, 

Fig. 2. Simple Bench Vise 

present in some form in all vises, by which the movable jaw is sepa- 
rated from the fixed jaw when the screw is backed out of the nut. 
In the machinist's vise both jaws are made of cast iron with 
removable faces of cast steel. These may be checkered to provide 
a firm grip for heavy work, or may be smooth to avoid marking the 
surface of the plate operated upon. When holding soft metal, even 
the smooth steel jaws would mar the surface; and in such cases it is 
customary to use false jaws of brass or Babbitt metal, or to fasten 
leather or paper directly to the steel jaws. The screw and handle 
are made from steel and the nut from malleable iron. 


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The common method of fastening a vise to the bench is by 
means of the fixed base shown in Fig. 2, although a swivel base 
is really preferable. Vises of this kind often have swivel jaws as well, 
which enable them to hold tapered work securely. This swivel jaw 
is provided with a locking pin, which fixes the jaws in a parallel posi- 
tion. The height of the vise from the floor depends somewhat on the 
class of work to be performed, but a general rule is to have the top of 
the jaw about 1J inches below the point of the elbow when standing 
erect beside the vise. 


Chisels. One often hears the term "cold chisel mechanic ,, used 
in derision, but the man who can by the use of a hammer and hand 

Fig. 3. Methods of Using Chisels on Bolts and Nuts 

chisel remove metal neatly and without marring the adjacent parts is 
a really good mechanic. The term came from the common practice 
in the early days of the automobile of tightening nuts in place with a 
cold chisel, which, of course, scarred the nuts very badly. This 
practice was more the fault of the maker than of the mechanic, as 
there were places on the automobile where a wrench could not be used. 
But this difficulty has been corrected on modern cars, and there is 
now practically no excuse for the use of the cold chisel in this manner. 


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It is often necessary, however, to remove interfering lugs, etc., 
when fitting accessories to a car. This is especially true when putting 
ignition apparatus, lighting and starting equipment, and other attach- 
ments on Ford cars. In cutting soft steel with a hand chisel there is 
little danger of doing damage except by cutting too deep or letting the 
tool slip, but in cutting cast iron, cast aluminum, and cast brass, which 
are the metals usually encountered on the motor car, there is great 
danger of cracking the adjacent part in case deep cuts are attempted 
with the necessarily heavy hammer blows. 

A survival of the-pld cold-chisel-mechanic days is found in the 
method of removing nuts. In these days such practice should seldom 
be necessary around the engine, but it does sometimes happen that 
nuts on the muffler and other chassis parts become so badly rusted in 
place that they cannot be removed by a wrench even after the kero- 

Fig. 4. Common Forms of Hand Chisels 

sene-oil treatment. The first thing is to try to start it with a dull 
chisel at A, Fig. 3, but if this does no good and it is desired to save 
the male member, the nut can be split as shown at B. If it is on only 
an ordinary bolt that can be renewed from stock, it is easier to sheer 
the bolt, as at C, Fig. 1. 

Cutting keyways by hand and putting oil grooves in anti-friction 
metal bearings are the other two uses made of the cold chisel by the 
automobile mechanic, and these subjects will be taken up in detail 

Chisel Types. Common forms of hand chisels are shown in 
Fig. 4 in the following order from left to right: flat, cape, diamond, 
and two types of round nose. 

Flat Chisel. The flat chisel is the most used and works best where 
the surface to be cut is of less width than the edge of the tool. It is 


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beveled on both sides, an included angle of 70 degrees being best for 
cast iron, while 60 degrees seems best on wrought iron and steel. 

Cape Chisel The cape chisel is a narrow chisel with the sides 
ground back so as to give clearance to the cutting edge in a channel. 
It is used particularly for cutting keyways and for making channels in 
a large surface preparatory to using a flat chisel. 

Diamond Point The name describes this tool, which is used for 
cutting sharp-bottomed grooves and for putting holes in sheet metal. 
It has little application in automobile work. 

Round Nose. Round-nose chisels, some very small, are of great 
importance in cutting the oil grooves in babbitt and die-cast bearings. 
These are often made with curved shanks. 

Chipping. The ball-peen hammer seems best balanced for the 
chipping process, and the size of the hammer should be consistent with 
the chisel being used and the class of work in hand. Warning has 
already been given against unnecessarily heavy blows on any part of 
iron, aluminum, or brass casting, because these metals are very brittle. 
Only the cutting edge of the chisel should be in contact with the work, 
the lower bevel being at a slight angle. For a deeper cut the sljank is 
raised, and for a shallow cut the lower bevel should almost touch the 
work. The general tendency is to raise the chisel too high and thus 
drive into the piece instead of making a good cut. 

Filing Methods 

Types of Files. The greatest time-saver in filing, as a feature of 
bench working, is in the selection of the correct file for the work at 
hand. It is therefore imperative, if a shop is to be at all efficient, 
to have a stock of files which will take care of every kind of work. 
Although there are a great number of shapes and sizes available with 
every imaginable type of cutting surface, those most commonly used 
are the flat file, hand file, warding file, square file, triangular file, 
half-round file, and the round file. 

You can obtain a file which will cut across one angle of the file 
or one in which the cutting surfaces cross each other. These are 
known as single or double files. Different materials to be worked on 
require different coarseness of the cutting surfaces, and there are five 
general grades most suitable for general work: coarse; bastard; 
second cut; fine, or smooth; and superfine, or dead cut. 

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File Shape. In files of fine cutting surface, the length is much 
shorter than in files with coarse cutting surface. The reason for this 
is obvious, inasmuch as in heavy cutting one needs a long clean sweep 
where plenty of muscular effort may be applied to the best advantage; 
while in fine cutting where the work is more delicate, one needs a file 
which is light and easy to hapdle. 

Properly constructed files have a very slightly convex surface in 
the direction of their length. The reason for this is that a perfectly 
flat file surface, digging-in to the full depth of its cutting ability, 
presents too much cutting surface to be handled by manual power. 
With a convex surface, however, the file is first applied at the center of 
the cutting surface, and this bites into the metal, allowing the rest of 
the file to be carried in easily. This convexity avoids dulling the 
cutting teeth, for it prevents frequent skimming strokes over the 



D E F Q 

Fig. 5. Sections of Different Types of Files 

surface of the metal which, as they apply only the sharp edges of the 
file, quickly breaks them down. This is naturally, not the case when 
the teeth are deep into the metal. Another purpose which this con- 
vex surface serves is to compensate for the bending to which a file is 
naturally subjected when pressure is applied to it. Although convex 
in its natural position, the bending action of the file, due to its pres- 
sure after the teeth have cut in, very nearly makes up for the convex- 
ity. This is, of course, not an accurate compensation. 

Proper Files for Certain Work. Before discussing the proper 
methods of handling files, it will be well to discuss the kind of file to 
select for a certain work. This is a matter upon which no fixed rules 
can apply. One mechanic may do a certain job with a long coarse 
file, where another may do the same job in equally quick time and as 
well with a finer cutting surface. 


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Generally, however, the kind of metal being worked determines 
the character of the file to be used. For cast iron, which presents a 
clean surface free from scale and an undue amount of rust, a bastard 
file is generally used. Although this is a softer metal than steel, it 
presents a surface of porous glassy character which is very hard on 
the cutting surfaces of a file. Old files — ones whose cutting surfaces 
have already been dulled by long use — should be used in east-iron 
work. On steels of all kinds a sec- 
ond-cut file is generally accepted as 
presenting the best surface. The 
superiority of the second cut over 
the bastard for steel work is due to 
the fact that the cutting surfaces 
are shorter, and when sufficient pres- 
sure is applied for the file to bite 
into the surface, there is less tend- 
ency for these surfaces to chip off 
than there is with a coarser file such 
as the bastard. 

Aluminum, bronze, brass, bear- 
ing metals of all kinds, and kindred 
soft metals permit the use of flat files 
with coarse cutting edges. 

Manipulation of Files. In filing, 
the work is usually held rigid in a 
vise, although many jobs are done 
directly on the automobile itself. 
In bench work, the surface should be 
at about the height of the elbow, and in constructing benches and 
installing vises it is well to bear this in mind. 

Handles. Although it might appear to be a trivial matter, one 
cannot be too particular as to the, kind of a handle which is fitted to 
the file. Before buying your files, hold them in your hand, with the 
handle against the palm and the other hand holding the steel end of 
the file. Press the file vigorously against a surface and determine for 
yourself whether the handle fits the palm in such a way that several 
hours of work would not become painful. Also make sure that the 
axis of the handle is on a true parallel with the file. 

Fig. 6. Correct Bench Filing Position 


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Position for Filing. If one is to undertake a filing job which will 
require several hours of concentrated labor, it is well for him to learn 
that position which will give greatest accuracy and which, at the same 
time, will be the least tiring. The feet should be placed a foot apart 
and at right angles to the work bench, or nearly so, Fig. 6, the left 
foot being in line with the top of the vise and the right slightly ahead 
of the left. This position allows the body to follow the file accurately 
and eliminates that swinging sideways movement which] is disastrous 
to accurate work. 

Holding the File. Take hold of the handle of the file with the right 
hand as you would take hold of the steering wheel of the car, with the 
fingers underneath and the thumb lying across the top. When a big 

Fig. 7. Position of the Hands for Bench Filing 

file is used and the work is heavy, grasp the steel end of the file with 
the left hand by placing the top of the file into the palm and twining 
the fingers around the end, Fig. 7. If the work is delicate, it is only 
necessary to pinch the end of the file with the fingers of the left hand. 
Remember that the first dozen strokes of a new file on a tough 
piece of steel frequently lessens its cutting value as much as an hour of 
steady cutting on a softer metal. Handle the file firmly and push it 
into the metal with an even steady stroke to avoid chipping the edges. 
When much metal is to be filed, the direction of stroke should be 
changed frequently, thus permitting more accurate work as well as 
allowing faster removing of metal. The file, when moved endwise, 
produces small grooves in the direction of the work; when the direc- 


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tion of the file is changed, it cuts into the top edges of the grooves with 
much the same effect as working against the grain in wood. 

Uses of Different Shapes of Files, We have gone into the types 
of files to be used as to coarseness or fineness of the cutting surfaces. 
Now let us consider the shapes best suited to various kinds of work. 

When one selects a file for a certain job, he must bear in mind the 
shape and the size of the work, the quajity of the metal, the amount of 
stock to be removed, and the quality of the finished work. The first 
two mentioned requirements fall under the shape of the file, the others 
under the nature of the cutting surfaces. 

If the surface is a flat one, the flat file, hand file, or warding file 
will serve. The length will, of course, depend on the length of the 
surface to be filed. For very light work the length of the file should 
be about 8 inches, and for heavy work about 18 inches. If the sur- 
face is a, square interior, such as a keyway, the square file finds its place. 

The triangular file finds its use in notching round bars, in cutting 
through steel tubing, and in filing gear teeth, bolt threads, and kin- 
dred applications. The half-round file is used where the curvature of 
a radial filing job becomes too great for efficient work with a round file. 
With these large surfaces, it is not possible or even desirable to have 
the file fit accurately the surface to be cut. In using this file it is impera- 
tive, if smooth work is to be done, that the file be given a side sweep 
with each stroke. The round file, which in its general form is tapered 
throughout its length, has obvious uses in working with round holes. 

Accurate Filing. The matter of accurate filing is a knack which 
can be acquired only by practice^. It is the process of learning a 
smooth even stroke in which the file is held flat against the work 
throughout the length of the stroke. However, the file maker has 
contributed towards accurate work in a safe-edge instrument which 
has innumerable applications around a motor car. 

Use of Safe Edges. Suppose one desired to increase the depth of 
a keyseat without in any way impairing the surfaces on the sides of 
that keyseat. If he were to introduce a flat file with cutting edges on 
all four surfaces, he would have removed considerable metal consti- 
tuting the sides of the keyseat before he had cut the keyseat much 
deeper. For this kind of work there is the safe-edge file — one in which 
there are cutting surfaces on two opposing sides and smooth surfaces 
on the other two. These are procurable in all sizes and shapes. 


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Draw Filing. The term draw-filing refers to the process of opera- 
ting the file over the work at right angles to the length of file. To 
do this work properly, the file is grasped in the palms of both hands, 
as one would grasp the handles of a push cart, Fig. 8. The purpose of 
this method of filing is accuracy in the work. As the belly of the 
file can be brought to bear on the high spots under better control and 
with less oscillation than in cross-filing, a less skilled mechanic can 
obtain more accurate results. Of course, due to the fact that the 
cutting surfaces operate on a great angle, the amount of cut at each 
draw is far less than it is in cross-filing. 

Filing to a Micrometer Fit. Suppose one has a square block of 
steel, one side of which is to be cut down to an accurate surface with 
^5 inch of stock taken off. Calipers or micrometers should be set 

Fig. 8. Position of the Hands for Draw Filing 

about tt inch greater than the finish size of the block. The surface 
may now be cut down with a flat second-cut file until the piece will just 
pass within the calipers or micrometers. Now the micrometer or 
calipers should be set to the exact dimension of the finished piece, 
and draw filing should be resorted to so as to cut down the surface 
carefully until the caliper or micrometer is a very tight fit over all 
the edges and through the center. 

Now one should use a small file of a smooth fine grade for the 
final dressing off and should resort to the cross-filing method, so as to 
remove the grooves caused by the draw-filing operation. With a little 
filing, then a measurement from the caliper or micrometer, a little 

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more filing, and still another measurement, etc., a very accurate job 
is possible. 

Revolving Filing. Quite another angle is presented in revolving 
filing. This means the filing of a piece of work which is revolving in a 
lathe chuck. The stroke for this kind of work is entirely different 
than in hand filing. These strokes are fewer and of longer duration 
inasmuch as the work is revolving rapidly and permits of faster 
cutting. In filing rotating work very nearly all of the cutting edges 
should be brought into play, that is, one should stroke slowly from one 
end of the file to the other. 

The file should be held in the hands in the same manner as for 
cross-filing in a vise, as previously described. If the amount of 
metal to be removed is considerable, the file should be held at an angle, 
and, if it has single cutting edges, at the angle which presents these 
edges, flat against the work. The file should be turned over fre- 
quently and held at the opposite angle, thus cutting crosswise of the 
grooves caused by the cutting edges of the file/ 

If a smooth finish is required and the amount of surface to be 
removed is nominal, the file should be held at right angles with the 
work and turned over frequently. It should be swept in even move- 
ment from the right to the left of the surface being filed. 

It must be remembered that less pressure is required to make 
the file bite in revolving work than in stationary work. This permits 
the use of special files for rotating work with concave surfaces which 
would not suit at all for stationary work. If one does not desire to 
purchase special machine files, there is an opportunity for using up 
the old stock which have become so warped and worn that they are 
no longer suitable for accurate bench work. This applies to the 
cutting of the radial surface of rotating work. If one is to file a flat 
rotating surface, such as the end of a disc, one must use an accurate 
file with a convex surface, the same as for bench work. 

Cleaning Files. It is quite important, if one hopes to minimize 
the purchase qf new files, that the ones in use be carefully cleaned after 
each operation. If the particles of metal removed in the cutting 
operation become packed into the teeth, this greatly diminishes the 
cutting powers of the tool. This cleaning may be done to some extent 
by striking the edge of the file against a solid surface, but such a cure 
is not a good one. The work can be done more effectively by using 


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a wire brush made for the purpose or by scraping the edge between the 
cutting surfaces with a thin piece of brass. 

Presence of Grease. In filing any metal on the bench, it is well 
to assure yourself that all grease is removed both from the file and 
from the work. Grease tends to hinder the file from cutting into the 
metal. In steel work, where the job is revolving, the file may be 

frequently oiled, as this measure 
tends to keep the file clean. 

When one is obliged to file 
objects in inaccessible places 
about an automobile, there is no 
rule which can be laid down other 
than to do the filing in the easiest 
possible manner. The work re- 
quired is seldom so extensive that 
the file will be harmed, no matter 
how carelessly the work is done. 


Types of Jig to Use. There 
are still a few cars running which 
embody the old principle of solid 
bearings in which the bearing 
metal must be poured into the 
bearing container. This process 
is known as rebabbitting bear- 
ings. It is not good practice to 
use the main shaft for the purpose 
of casting the bearings, because 

Pig. 9. Jig for Rebabbitting Bearing. the hot metal J g &pt to spr } ng the 

shaft. A better plan is to use a wood jig such as shown in Fig. 9. 
It is unfortunate but true that a new jig will probably have to be 
made for every different size of job, but the jig is easily turned in a 
lathe in one set-up of the chuck. The solid flange A should be about 
1 inch thick and should have a diameter 1 inch or so greater than the 
outer diameter of the bearing. The shaft C should be turned to a 
size ^r inch smaller than the size of the bearing surface, and should be 
about J inch longer than the length of the bearing itself. Then on the 


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shaft side of the flange A should be turned a groove B having a depth 
of i inch and a diameter equal to the diameter of the hole through the 
connecting rod when the babbitt metal is removed. 

Pouring the Babbitt. The jig is now ready for use. Fill the 
groove B with plastic fire clay even with the surface of the flange and 
place the bearing container 
over the shaft of the jig, as 
shown in Fig. 10. The 
bearing container should be 
adjusted over the shaft of 
the jig so that the space on 
all sides is exactly the same, 
determining this with a 
tapered steel gage, Fig. 11. 
Drop the gage into one side 
and note the mark on the 
taper where it comes to rest 

When touching the jig Shaft Fi * 10 - Jfej an ? Bearing Container 

° . Ready for Pouring 

and the bearing container. 

Then move the gage about and determine whether the other side is 
too close or too far away. Continue this operation until the space to 
be filled is the same on all sides. It is important that the machined 
surface of the bearing container rests perfectly flat on the block. 

With everything properly located, lay a rim of fire clay about i 
inch thick around the top of the bearing container, as shown in Fig. 5, 
so that the space between can be filled with bearing metal above the 
edge of the container to take care of contraction. 

Everything is now ready for the pouring of the bearing metal, 
which has been melted in a ladle. Before starting to pour, make sure 

r'f if g 

Fig. 11. Tapered Steel Gage 

that all impurities which have risen to the top are skimmed off. These 
impurities, if allowed to pass into the bearing, might cause trouble 
later. Pour the metal from the ladle into the hole quickly and with a 
circular movement about the rim of the hole. It is important that it 
be poured in quickly, because babbitt cools very rapidly. However, 


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this does not imply that the metal should be splashed in recklessly 
with the probability of throwing out the setting of the jig. 

Finishing the Bearing. Allow the metal to cool for a period of 
30 minutes and then remove the jig by pulling it out of the hole with 
a screwing motion. If care has been taken in placing the clay, the 
babbitt bearing will be held firmly in the bearing container. If the 
bearing is too tight for the crankshaft, it may be scraped to a proper 
fit as described in the next section. 

When babbitt bronzes are to be relined, it is also necessary that 
there be a core to fit within the bronze, this core to be the size of the 
piece upon which the bearing operates. 

Of course it is necessary, after the pouring has been done, to chip 
off the excess babbitt on the upper and lower surfaces of the bearing, 
smoothing down these edges after the bigger portion has been chiseled 
off by the use of a coarse file. The final polishing may be done with a 
fine file. 


To the amateur repair man, scraping bearings looks like a tre- 
mendous task. But if the proper facilities are at hand, it is a com- 
paratively easy matter for a man with some shop experience. 

Dismounting the Motor. In order to properly scrape both the 
connecting rod and the crankshaft bearings, the crankshaft must be 
removed. There is a method of scraping the crankshaft, or main, 
bearings without removing the crankshaft, but this operation is too 
difficult for the average repair man. The first step, of course, is to 
get the crankshaft out of the motor. This is done by first removing 
the motor from the frame, after it has been drained of all oil and water, 
and setting it on a motor stand, or on the bench if a stand is not avail- 
able. The flywheel is now taken off, and then the cylinders. All that' 
remains on the bench or stand is part of the crankcase with the 
crankshaft, connecting rods, and pistons. In most cases the removal 
of the pistons is necessary. By dropping the lower half of the crank- 
case, the crankshaft and connecting rods may be removed. This 
assembly should be placed on the bench and the connecting rods 
removed. Of course if the rods may be removed while in the motor, 
as is sometimes the case, it is advisable to do so. 

Holding Crankshaft. A means of holding the shaft upright on 
the bench must be devised. Usually on the end of the shaft, there is 


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a flange with a number of holes drilled through. Place the flange end 
of the shaft on the bench, as shown in Fig. 12, and mark on the bench 
with chalk the places under the holes. Drill holes through the bench 
where the chalk marks appear, and bolt the shaft to the bench, using 
as many bolts as you have holes. The bolts should be long enough to 
run through the bench and have 1 inch left over. 

Cleaning and Fitting Connecting-Rod Bearings. With the 
crankshaft in the position shown in Fig. 12, clean the shaft thoroughly 
with gasoline. Emery cloth should be used to 
rub down any cuts which appear. 

Cleaning Parts. Immerse the connecting- 
rod parts in gasoline, and then rub them dry. 
The connecting rods, like the cylinders, are 
numbered from the front to the back of the 
motor, and in working with them, never put 
a rod in any but its proper position; that is, 
rod No. 1 should always be fitted to wrist 
No. 1. The connecting rods are now ready 
for an initial fitting. 

Putting Lampblack on the Crankshaft. 
The connecting-rod wrists on the crankshaft 
having been cleaned and polished thoroughly 
with emery, the wrist corresponding to the rod 
to be fitted is blackened with lampblack. Let 
us say that rod No. 1 is to be fitted. A little 
lampblack mixed with oil is rubbed on the 
wrist with the finger. Connecting rod No. 1 is 
then placed in position and tightened. In 
doing this, care should be taken that the nuts are tightened as they 
should be. Many repair men make the mistake of assuming that the 
nuts may be drawn up in any order whatever. This is wrong. First 
tighten one nut a little, then the opposite one a little, then a third 
and the one opposite about the same amount. Now go back to the 
first and go over the nuts in the same order. This should be con- 
tinued until all the nuts are tight and the bolts drawn up as much as 
possible without springing them. The bolts are very easily stretched 
and, therefore, care should be taken that they are not tightened 

Fig. 12. Connecting Rod 

in Vertical Position for 

Adjusting Bearings 


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CuMing-In Bearing. When all the bolts have been drawn up, 
turn the rod around in one direction for awhile, then run it back and 
forth for a few minutes, and then all the way around again. The 
entire operation of cutting-in the bearing, as it is called, should last 
about 8 minutes. Then take off the connecting rod. The connect- 
ing-rod bearing will be covered with little black spots, caused by the 
lampblack being embedded in the soft metal of the bearing. A piece of 
clean emery cloth should be used to rub the surfaces of the bearing. The 
rubbing should be continued until the surfaces are as clean as possible. 
Filing Shims. If no black spots appear it is evident that the 
bearing was not touching the crankshaft at any point. If it is noticed 
that the rod does not fit snugly when the initial fitting is given, then 
the shims should first be filed. These are the thin pieces of metal 

which rest between the two halves of 
the connecting-rod bearing and regu- 
late the tightness of the bearing. A 
filing block of wood should be made 
as shown in Fig. 13. The block should 
be gouged on its surface in two places 
so that the resulting shapes resemble 
those of the shims. They need not fit 
Fig. 13. shims Mounted for Filing perfectly, but the indentations must 
be of the same depth and still too deep to prevent filing the surface of 
the shim. The shims, when placed in these grooves, are ready for filing. 
Both shims should be filed at the same time. The block should be 
placed in the bench vise or in a metal vise. Then a fine mill file should 
be run over the surface of the shims by holding the file as previously 
instructed. Do not file much, the object of filing being to bring the 
two halves of the bearing halves closer together so as to touch the 
shaft. It will be seen from this that considerable accuracy is neces- 
sary in filing shims. The shims should be perfectly level/ 

Scraping Process. With the shims filed, place them in position 
and give the bearing another fitting. Remember the filing was done 
to bring the bearing together. When it is properly closed, the rod 
should fit tight enough to require some effort to push it around. 
Taking for granted that the bearing has been given a fitting and that 
it has been found to contain a number of black spots, as shown in 
Fig. 14, the scraping will be begun. For this operation a bearing 


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scraper, Fig. 15, is used. This may be procured at any supply store. 
The scraper is held as shown in Fig. 14. However, one who is accus- 
tomed to scraping may be able to handle the instrument better in 
another position. One very 
important point must be 
borne in mind and that is 
that the word scraping does 
not mean — as it usually 
does — scratching; scratching 
is detrimental to the bearing. 
By scraping is meant cutting 
from the surface of the bear- 
ing a very thin shaving of 
metal and at the same time 
leaving the surface of the 
bearing smooth. 

The real object of scrap- 
ing is to get the bearing to 
touch the crankshaft at every 
point. A bearing may be said to be a good one if every fa inch of the 
surface touches the crankshaft. It will be supposed that the bearing 
needs scraping. It does not show little black spots every fa inch. 
Instead there are groups of spots, at each ejid as at a and 6, Fig. 14, 
while in the center portion c there are no spots, which means that at 
this point the bearing is not touching the shaft at all. The object of the 
scraping is to make the center portion as well as the two ends touch. 

The little black spots are scraped off one at a time or nearly so, 
using short clean strokes with the scraper and taking care not to 
roughen the surface of the bearing. The scraper should be moved 

Fig. 14. 

Inside of Bearing Showing Spots Which 
Need Scraping 

Fig. 15. Type of Bearing Scraper 

sideways and at the same time a little forward. One hand is necessary 
to manipulate the scraper and the other to guide the tool. 

After all the black spots have been removed, the bearing is thor- 
oughly cleaned with a cloth. The wrist of the crankshaft is again 
blackened with lampblack and the rod given another fitting. If at 


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this fitting the rod is loose, due to the bearing having been scraped too 
much, the shims should be filed a little. After the rod has been 
turned on the crankshaft for about 5 minutes, it should be removed 
and the bearing again examined. 

Little black spots will again be seen, but this time they will be 
more evenly distributed if the bearing was properly scraped before. 
If the entire surface of the bearing contains black spots about ^ inch 
apart, then the bearing is in good condition. But this holds true only 
if the rod holds snugly on the shaft. If the black spots are again 
grouped as shown at a, 6, and c, then the individual spot scraping is 
repeated until the rod gives a snug fit and at the same time has the 
_-_~™_ -_-__ bearing touching uniformly 

Bearing Scrapers from 
Old Files. Old files, when 
properly worked into shape 
and tempered, make excellent 
bearing scrapers. There are 
several advantages in favor 
of the use of a homemade 
scraper; first of all it is possible 
to make a scraper that will be 
more adaptable to the hands 
of the workman than the 
standard type. 

Triangular file ' 
fibovc File Mode Into Scraper* 

Round file 

Fig. 16. 

Round File Mode Inlo Scrapers 
Scrapers Made from Old Files 

In Fig. 16 is shown some of the types of scrapers best made from 
old files. The way to go about making a scraper is to select an old file 
resembling the type of scraper desired. Heat the file to a light-red 
heat and forge with a hammer, or bend in a vise as required. 

When this is done, allow the file to cool slowly in the ashes at the 
side of the forge. When cool, it will be much softer than in its original 
state and most probably will be soft enough to be filed readily into the 
exact shape desired. If too hard to file conveniently, an emery wheel 
may be brought into service to shape the tool. 

When the proper shape has been obtained, the next operation is to 
temper the tool. This is done by heating it again to a light red, then 
immersing the scraper portion in cold water and moving it about for a 
few seconds until it has entirely lost its red color. It should now be 
withdrawn and its bright surfaces quickly sandpapered so that the 


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changes of color can be noticed ; then when a light yellow or straw color 
appears, the whole tool should be immersed in water, moved about 
therein for a few minutes, and then left there until cold. 

The last step in the manufacture of the homemade scraper is to 
grind the surfaces of the tool so as to get smooth sharp-cutting edges. 
The sharp-edge scraper will of course have its three cutting edges 
formed by hollow-grinding the surfaces so that about & inch of the 
original flat surface remains on either side of the edge. These surfaces 
remain flat and afterward are smoothed up on an oil stone. 


General Instructions. It is quite necessary to make use of 
solder on various parts of the automobile, such as the radiator, the 
tanks, and the lamps, in spite of the fact that when subjected to stress 
or vibration such procedure is not considered best. Certain prin- 
ciples must be kept in mind if permanent work is to be accomplished. 
Cleanliness is a watchword; the surfaces to be joined must be clean, 
and this cannot be carried too far. Chemically, the metal must be 
clean as well as free from any oxide. The use of sandpaper or a file 
to clean and brighten the surfaces is recommended, and this work 
should be done immediately before the soldering process is begun. It 
is well to bear in mind that the surfaces of the metal as well as the 
solder must be hot if a permanent job is to be done. The solder must 
flow freely, otherwise it will not enter the pores of the metals. Always 
keep the soldering iron well tinned. Never let it get red hot. 

Soldering Flux. The ordinary flux is made by placing zinc clip- 
pings in strong hydrochloric acid until no more will dissolve. Some 
special preparations which are noncorrosive give very good results 
in soldering. Work soldered with the zinc-hydrochloride as a flux 
should be thoroughly washed afterwards. A list of the more usual 
fluxes for the different metals is as follows: 


Iron or steel Borax or sal ammoniac 

Tinner iron Resin or chloride of zinc 

Copper to iron Resin 

Iron to zinc Chloride of zinc 

Galvanized iron Mutton tallow or resin 

Copper or brass Sal ammoniac or chloride of zinc 

Lead Mutton tallow 


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« Light Work. Light work in wire, sheet, and tubes of copper, 
brass, or iron can be soldered with an ordinary soldering iron, or in a 
Bunsen flame. The essentials are thorough cleanliness from grease 
and oxide of the parts and the iron itself, a suitable flux, a good 
quality of solder, and the iron brought to the right temperature. 

Heavy Work. To solder a large tank or radiator, the water 
should be run out, the place to be soldered should be well prepared, 

and a large copper soldering iron — 
sometimes called a "bit" — should 
be used, preferably one which is 
automatically heated by a blow 
lamp. Such a repair is not easy to 
make, owing to the large cooling 
surface of the metal. The tank or 
radiator may have to be taken off 
the car in order to make the repair 
conveniently. A soldered joint, of 
course, will not resist much strain 
or vibration, and in some cases it is 

Fig. 17. Soldering Iron Heating Stove j • i_i ' • e i_ • r 

courtesy of Central Electric Company, advisable to reinforce the repair by 

Chicago, Illinois • . • a i i • • * • i 

riveting. A brazed joint is much 
stronger, but brazing is a much more difficult process and should be 
done only by a skilled operator. 

Position of Work. Soldering requires time and judgment. 
Sufficient time must be given for the heat to flow from the copper to 
the work. Seams should be held horizontally to prevent the solder 

Fig. 18. Electric Soldering Iron 
Courtesy of Central Electric Company, Chicago, Illinois 

from running away from the seam. The area of the joint being 
soldered must be large, as the elastic limit of solder is much below its 
tensile strength. Be sure that the soldered joint is not subjected to 
bending or other stresses that will localize the strain on the solder. 
Use of Blow Torch. If two pieces of considerable thickness are 
to be soldered, the work cannot be done successfully with a soldering 
iron, as the metal absorbs the heat faster than the iron can supply it; 


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consequently, repairs of this kind are usually accomplished by the use 
of a blow torch. First the ends of the two pieces to be soldered are 
tinned — covered with solder separately. Then the two surfaces are 
put together and the blow torch applied, melting the solder and form- 
ing a perfect union. Another method sometimes used is known as 
sweating, in which the two pieces of metal to be joined are first heated 
by a blow torch in order that the heat from the actual process of sol- 
dering will not be so largely consumed by the metal itself. The more 
tin there is in solder the stronger it is, but it is harder to melt than that 
in which lead is the predominating element. 

Special Stoves and Irons. Special stoves for heating soldering 
irons are made and vary in construction. Fig. 17 shows one of the 
most common forms of soldering-iron heating stoves. Some shops 
make use of an electric iron for soldering, wherein the temperature of 
the iron is uniform. Such a tool is shown in Fig. 18. 


Importance of Piston Rings. Notwithstanding the fact that 
the fitting of piston rings requires much accuracy, the average repair 
man is satisfied if the rings 
merely fit into the guides in 
the piston. If every repair man 
would only stop and think, he 
would realize that a great deal 
depends upon the condition of 
the piston rings and that con- 
siderable care should be exer- 
cised in fitting them to the 

Fitting Ring in Groove. 
The first move in fitting rings 
is to get the grooves or guides 
of the piston thoroughly clean. This should be done by immersing 
the piston in gasoline and spraying it thoroughly to remove the least 
particle of dirt. Much time may be saved by trying the rings in the 
various grooves to see which ring most nearly fits a given groove. 

In Fig. 19 is shown how the ring should be started in the groove, 
and the arrows show the direction in which the ring should be moved. 

Fig. 19. 

Starting Piston Ring in Groove 
to Test the Fit 


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The entire circumference of the ring should be rolled around the 
groove. Of course, if the ring will not fit into the groove, try another 
groove. The reason the back end of the ring is fitted first instead of 
the inner is because the latter fitting would require that the ring be 
put in its usual position around the piston. Slipping the rings over 
the piston head is not easy in itself and would be difficult were the 
rings not of the proper size. 

Testing and Correcting Length of Ring. The ring should next 
be inserted into the cylinder to determine whether the ends are the 
proper distance apart. The distance between the ring ends, when 

the ring is in the cylinder, varies 
with the different designs. An 
electric lamp dropped into the 
cylinder, while the ring is in, will 
show immediately whether the 
ends of the ring are touching. 
If they do touch, they should be 
filed slightly, as shown in Fig. 20. 
The ring should be placed in a 
vise with one end protruding 
about an inch. A little of the 
ring is left sticking out so that it 
will not sway when filing is being 
done. The file — a very fine mill 
file — is placed between the ends 
as the sketch shows, with the 
left hand pressing the long end of the ring lightly against the file. 
The operation should continue for a short time only, about twelve 
strokes of the file being sufficient. The ring should be put back in 
the cylinder and the distance between the ends measured with a thick- 
ness gage, or as it is called by factory men, a feeler. Fifteen- 
thousandths is a good distance to allow if the factory measurements 
cannot be obtained. 

Lapping In the Ring. The next step is to make the ring fit its 
groove properly. Lapping is the term applied to the operation of 
grinding the ring down so that it fits. A level steel surface is used, 
upon which is sprinkled enough very fine emery dust to cover it. 
Enough water is added to make a pasty mass. The ring is then 

Fig. 20. Filing Piston Ring to Give 
Proper Spacing 


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placed on the steel plate and a block of wood about 6 by 6 inches placed 
on top of the ring; by exerting a slight pressure on the block and apply- 
ing a rotary motion, the ring is moved about over the emery. 

If the ring will not stay under the wood block, cut a little notch 
in the block to hold the ring 
still. After grinding for a few 
strokes on one side, the ring 
should be turned over and an 
equal amount of grinding done 
on the other side. The entire 
operation should not last 
longer than one or two min- 
utes. After lapping, the ring 
should be immersed in clean 
gasoline and fitted to the 
groove which it most nearly **■ 2L Puttin « ^^ mng on Pi8ton End 
fitted before. If every part of the circumference of the ring fits every 
part of the groove, then the lapping is complete and the ring may 
be tagged to designate its location. The figures 1-1 on a tag usually 
represents the first cylinder 
ring No. 1 , this ring being the 
one nearest the top of the pis- 
ton. If one part of the ring 
fits and another does not, the 
place that is too tight will 
show up when the ring is 
dipped in gasoline and then 
rubbed with a cloth. The 
high spot will be more shiny 
than the rest. Lay the ying 
perfectly flat and with a fine 
file take a little off from both 
sides of the ring. Only a little should be taken off at a time, and the 
ring should be tried after each filing. 

Replacing the Rings. When all the rings have been filed in this 
way, the next step is to place them in their respective grooves, making 
them occupy their proper position when in use. In Fig. 21 is shown a 
method for doing this. Ring No. 4 should first be placed in position. 

Fig. 22. 

Using Metal Stripe in Properly Placing 
Piston Rings 


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For this operation, three pieces of saw blade with the teeth ground off 
are used. Hold one blade against the piston with the left hand and 
with the right hand bring one end of the ring in contact with the 
blade. Get the blade about £ inch from the end of the ring, so that 
the blade can be held in place by pressure against the ring. Then slip 
the ring over the piston top. There is a space on either side of the 
blade through which the other blades may be inserted. Push the 
blades around until they appear as shown in Fig. 22. By sliding the 
ring on the three blades, it may be placed easily in its groove. With 
the lapped ring in its groove, the ring must fit so that it may be turned 
around easily. No up and down play must exist. 

Miscellaneous Adjustments of Rings. There are several things 
to be looked for to determine whether the piston rings are functioning 
as they should. If gas has been working its way past the rings or if 
the rings have not been fitting the cylinder walls properly, points 
where the gas passed will be evidenced by burned, browned, or rough- 
ened portions of the polished surface of the piston and rings. Points 
where this discoloration is noted will more often be at the thin end of 
an eccentric ring, the discoloration being apparent about i to f inch 
each side of the slot. Possibly the rings were not true when put in. 

It is well to bear in mind that before replacing pistons in the 
cylinders one should make sure that the slots in the piston rings are 
spaced equidistant on the piston. If pins are used to keep the rings 
from turning, one should be careful to make sure that these pins fit 
into their holes in the rings and that they are not under the rings at 
any point. Putting pistons in cylinders really requires the use of two 
pairs of hands. The manipulation of pistons is discussed in Gasoline 
Automobiles, Part I. 

Fitting New Rings. Fitting new rings will not prove of advan- 
tage unless the cylinders are in good condition. Before making a new 
ring installation, make sure that the cylinders are not out of round, 
warped, or scored. If found to be so, they should be reground and 
oversize pistons and piston rings installed. Piston rings must have 
a uniform wall pressure of sufficient strength to maintain a bearing 
against the cylinder walls during every revolution of the engine. 
Piston rings that will assume the shape of the worn or warped cylinder 
do not have the necessary wall pressure and will collapse under the 
force of expansion. 


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Principle of Operation. In case measurements are required 
to be more accurate than can be obtained with the ordinary calipering 
devices, the micrometer caliper, as shown in Fig. 23. is used. The 
accuracy of its measurements is determined, not by direct setting to 
two lines, but by finely dividing the pitch of the measuring screw and 
furnishing means for reading these subdivisions. It is a registering as 
well as an indicating caliper, and thus serves the purpose of a common 
caliper in combination with a rule, but with a much greater degree of 

Essentially, the micrometer caliper consists of a cresfcent-shaped 
frame carrying a hardened steel anvil B at one end and a nut of fine 
pitch at the other, the axis of the nut being at right angles to the face 

Fig. 23. Transparent View of Micrometer Caliper with Friction Stop 
Courtesy of L. 8. Starr ett Company, Athol, Massachusetts 

of the anvil. The outside of the nut A forms a projection beyond 
the crescent that is called the barrel. The measuring screw consists 
of a finely pitched screw to fit the nut, combined with a measuring 
point C, having a face parallel with that of the anvil. To the outer 
end of this screw is firmly attached a thimble 2), which fits closely over 
the barrel. The edge of this thimble is beveled at A so that gradua- 
tions placed on the edge come very close to the barrel. A reference 
line is drawn on the barrel, parallel to its axis and graduated to repre- 
sent the pitch of the screw. The chamfered edge of the thimble is so 
divided that the movement of one division past the reference line on 
the barrel of the instrument indicates a movement of the measuring 
point of .001 inch. To illustrate: if the pitch of the measuring 
screw is .01 inch, there should be ten divisions on the thimble; if .02 


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inch, twenty divisions; if" .04 inch, forty divisions. Most measuring 
screws have a pitch of .025 inch and these are the type usually used, 
every fourth dimension on the barrel being lengthened and num- 
bered to indicate tenths of an inch. 

How to Use Micrometer. When using the micrometer caliper, 
it should not be set to the size desired and pushed over the work, but 
should first be opened, then screwed down until the measuring point C 
and the anvil B are in contact with the work. The size may then be 
read by taking the number of scale divisions on the barrel and adding 
the value of the parts on the thimble corresponding to the reference 

Fig. 24. Inside Micrometers 
Courtesy of L. S. Starrett Company, Athol, Massachusetts 

line on the barrel. The proper degree of pressure to be applied to 
the screw is acquired only after extended practice, and some manufac- 
turers place a friction device on the thimble, as shown at the extreme 
right of Fig. 23, so that undue pressure cannot be exerted. 

Value of Micrometer. The value of the micrometer caliper can- 
not be impressed too strongly upon the user. Not only does it show 
when work is too large or too small, but it gives the exact amount of 
variance in desired measurements. It is a distinct improvement over 
the caliper and enables the user to work with accuracy. The 1-inch 
size is the most common, but micrometers may be obtained in all sizes 


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up to 20 inches. Using the micrometer for inside measurements is 
not the usual application, but it is easy to arrange and makes a very 
simple instrument, as shown in Fig. 24. The ordinary micrometer 
head is used, except that the outer end of the thimble carries a contact 
point, attached to a measuring rod which may be of any length. The 
shortest distance that can be measured with this device is about 2 
inches, but there is hardly any limit to length, since the rigidity of 
the rod is easily accounted for. It is evident that such rigidity is 
harder to obtain in the curved shape necessary for outside measure- 
ment, which fixes the outside limit of this form to about 20 inches. 
Reading the Micrometer. All readings are in thousandths. 
The usual micrometer has forty threads to the inch and the thimble 
has twenty-five divisions on its circumference. The barrel is divided 
to correspond to the pitch of the screw with each fourth division 
numbered. In reading, first note the highest numeral visible on the 
barrel and express it as so many hundred thousandths; then read the 
short divisions on the barrel, calling the first division twenty-five 
thousandths, or .025; the second, fifty thousandths, or .050; and the 
third, seventy-five thousandths, or .075. Now read the number iftdi- 
cated on the thimble, that is, the number that has passed the line 
running lengthwise. Add this reading to the readings of the short 
divisions. The result of adding the highest numeral visible on the 
barrel, which is expressed in hundred thousandths, the short divisions 
on the barrel and the number indicated on the thimble, give the dis- 
tance from the anvil to the measuring point. If the micrometer 
caliper is a good one, we may be sure the distance does not exceed or 
fall short of the figures given by .001 inch. 


Worn Cylinders. Where a cylinder of an automobile engine has 
become worn slightly out of shape or where the rings do not bear 
equally on the surface of the cylinder wall, the defect may be remedied 
entirely or to a great extent, depending on the magnitude of the defect, 
by lapping the cylinder wall. This measure will not cure the cylinder 
which has become scored but applies only to one which has been worn 
a very few thousandths of an inch out of round. 

Lapping by Hand. The job can be done satisfactorily only by 
using an old piston of the same bore as the cylinder which is being 


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worked upon. If one does not have a drill press, the hand operation, 
which will give a very satisfactory job, should be done as follows: 
Support the cylinder in its inverted position on the work bench. 
Inasmuch as practically all motors of present-day construction are of 
the block cast type, this heavy casting should be well supported in an 
upright position in order that the lapping may be done conveniently. 
Cleating Doum the Casting. Probably the best and easiest way to 
support the casting is by cleating it to the bench, as shown in Fig. 25. 
If the motor is a four- or six-cylinder block-cast type, use three sets 

of cleats on each side, 
rhese consist of a block 
of wood laid against the 
side of the cylinder block 
and clamped in place by 
wood pieces mitered off 
ata45-degree angle, the 
mitered edge of one end 
nailed to the block and 
the mitered edge of the 
other end nailed to the 
work bench. This cleat- 
ing will support the block 

Proper Fit for Piston. 
Before proceeding with 
the work, one must de- 
termine that the old piston which is to be used is a proper fit in the 
cylinder to be lapped. It must be such a tight fit as to require con- 
siderable pressure to move it up and down. On the other hand, a 
loose fit will mean uneven grinding and a great deal more work to 
obtain the proper lapped surface. 

The piston should have a connecting rod fitted into it, or better 
still, a rod of such a length that it will protrude about 18 inches above 
the top of the piston. If one contemplates an extensive business in 
cylinder lapping by the hand method, it would be well to fit up a num- 
ber of standard size pistons with rods such as just described. The 
connecting rod itself, however, will serve the purpose if the jobs are 
so few that they do not merit the special tools. 

Fig. 25. Cleating Casting to Bench 


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Emery Paste. With the cylinders blocked up on the work bencn 
and a suitable piston at hand, one is ready for the lapping operation. 
There are several pastes on the market made up of fine emery and an 
oil body which are excellent for lapping -work. However, one can 
make the necessary material himself with very fine emery dust, 
ordinary motor oil, and a bit of graphite worked into the paste. This 
compound should be made up to the consistency of library paste and 
applied thoroughly to the walls of the cylinder to be lapped and to 
the surface of the piston to be used for the lapping. 

When applying the paste, watch the surface upon which it is being 
applied with great care, especially 
if the paste has been made up 
previously and allowed to stand 
around the shop for some time. It 
is very easy for metal chips and 
filings to be dropped into the 
paste, and if these get into the 
cylinders when the lapping 
operation is under way, they are 
liable to scratch, or score, the 

Grinding Process. Lower the 
piston into the cylinder and pro- 
ceed with the lapping. In per- 
forming this, lower and raise the 
piston, at the same time main- 
taining a circular motion, thus 
turning the piston around so that 
all surfaces of the piston will be brought to bear upon all parts of 
the cylinder. 

This operation should be continued for a period of from 15 to 30 
minutes, depending upon the condition of the cylinder interior. It 
will not remove scratches and scores and will not iron out a warped 
or egg-shaped cylinder, but it will dress down the small humps and 
impart a very smooth gUss-like finish to the cylinder walls. 

Lapping by Drill Press. If the repair shop is equipped with a 
fair size drill press, lapping can be performed quickly on this machine. 
It is especially easy when one has to deal with separate cast cylinders 

^Drill Press Table 
Fig. 26. 

Cylinder Mounted on Drill Press Bed 
for Lapping Job 


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inasmuch as these can be clamped into the drill-press bed without need 
of special supports, Fig. 26. Howfever, if the job is a block-cylinder 
casting, one must provide some means of support outside of the drill- 
press bed and inasmuch as it is a matter of blocking from the floor, it 
is for the ingenuity of the repair man to devise the best method. 

Piston Rod. In drill-press lapping of cylinders it is, of course, 
necessary that a rod be used to take the place of the connecting rod, 
this rod to fasten to the wrist pin at one end and be so shaped as to 
lock into the chuck of the drill press at the other end. 

It is well to cut a block of wood which when dropped into the 
inverted cylinder will come up to the line which marks the top of 
the piston stroke. To lap the cylinder, the old piston is coated with the 
lapping paste as previously described and let down into the cylinder. 
The drill press must be turned at its lowest possible speed. When the 
lapping is going on, the drill-press arm should be let up and down so 
that the position of the piston is constantly changing within the cylin- 
der. Of course lapping by this method can be accomplished in about 
half the time required by the hand method. 

Cleaning after Grinding. At the completion of hand or machine 
lapping, the cylinder interior should be thoroughly washed out with 
gasoline and the surface polished with a soft cloth. It is imperative 
that all emery be removed from the cylinder as it would undoubtedly 
injure the bearings or some other part of the motor, after the motor has 
been assembled and run. 


Types of Drills. There are two kinds of drills which are found in 
modern repair shops, the twist drill and the flat drill. The former is 
the one which is used in practically every kind of work, although the 
flat drill has as its function the performance of certain operations 
which the twist drill will not handle at all. 

Flat Drills. The flat drill, Fig. 27, is the simplest and., inciden- 
tally, the oldest type; until the invention of the twist drill, the flat 
drill was used for all drilling work. It is made from a piece of round 
stock, on the end of which are forged thin lips which are ground with 
three cutting edges, the edges being on the V-shaped end of the tool. 
For the performance of accurate work the flat drill is a poor tool, its 
field being in rough drilling of extremely hard metals. As a deep 
hole drill it is useless because it does not free itself of chips. For 


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drilling out a cored hole in an iron of steel casting preparatory to 
boring, the flat drill is superior to the twist drill, inasmuch as this 
work is very injurious to the twist drill because of scale and sand which 
is bound to be within the core. 

Fig. 27. Blacksmiths' Flat Drills 

Tvrist Drills. In small drill sizes, the twist drills come in straight 
shanks, Fig. 28, while in the larger sizes, taper shanks, Fig. 29, are 
most generally used. The shank is the part of the drill which fits into 
the holding device whether it be the chuck of a drill press or a bit. 

Fig. 28. Typical Twist Drill 
Courtesy of Union Trout Drill Company, Athol, Massachusetts 

As will be seen from the illustrations, a twist drill is fluted or 

grooved in spirals which follow the direction of rotation of the drill. 

These flutes serve to carry the chips from the cutting edges which, as 

is the case with the flat drill, are on the V-shaped end of the tool; the 

c B ^ 

Fig. 20. Taper Shank Twist Drill 
Courtesy of Morse Twist Drill Company, New Bedford, Massachusetts 

flutes also act as a channel through which lubricant may be directed to 
the cutting edges. For small drills the blanks are usually made from 
steel wire and for large drills from round steel stock. The flutes are 
milled into the tool. 


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Morse Tapers 

Smallest Drill 

Labobst Drill 

No. or Taper 

Taper prr Foot 

Using Each Tapeb 

Using Each Taper 



















i 6 




1 6 




Grinding Drills. Great care must be exercised in grinding the 
twist drill. The angle of lip clearance — the lips being the cutting 
edges — should be greater at the center than at the outside of the lips. 
This is to permit the part of the drill which first touches the metal to 
be drilled to bite in. The usually accepted angle is about 12 degrees, 

as shown in Fig. 30. If the 

difference in the angle on the 

lips is too great, the drill bites 

too quickly, which may result 

in tearing off or chipping the 

cutting edges. If , on the other 

hand, the angle is too small, 

the cut is slow, and the drill 

will consequently heat excessively. Although there are a number 

of drill grinders on the market which do satisfactory work, the use of 

drills in a motor-car repair shop is seldom sufficient to warrant the 

purchase of one. After a little experience with drilling, one can 

determine the angles which give the best results by the "feel" of the 

drill and the dull drills can be ground accordingly. 

Sizes of Drills. The taper-shank drill is made in six sizes and 
the shank has the Morse taper. The exact taper and the limiting 
sizes for which each drill is generally used are given in Table I. 

These taper-shank drills are carried as regular stock in all sizes 
by 64ths from £ to 2 J inches and by 16ths from that size up to 3 inches. 
If one needs a drill larger than 3 inches, which would surely be a rare 
occasion in garage work, that drill would have to be made to order. 
The wire gage sizes run by number rather than by dimensions, 
ranging from No. 80, the smallest twist drill made, up to No. 1. 


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S.A.E. Standard Taps and Drills 

Subs of Taps 

Sura or 

J inchX28 threads 

A inch 

H inch 

| J inch 

i inch 

A inch 

i inch 

A inch 

U inch 

H inch 

H inch 

H inch 

1A inch 

1A inch 

ltf inch 


A inchX24 threads 

I inch X24 threads 

A inch X 20 threads 

i inch X 20 threads 

A inch X 18 threads 

I inch X 18 threads 

H inch X 16 threads 

} inch X 16 threads 

i inch X 14 threads 

1 inch X 14 threads 

lj inch X 12 threads 

li inch X 12 threads 

If inch X 12 threads 

11 inch X 12 threads 

The above tap drills allow a thread within A inch of full thread. 

Speed of Drills. The speed at which drills are driven has an 
important bearing on their wearing quality. Of course small drills can 
revolve faster than large drills. The proper feeds for drills — which 
means the speed of cutting as regards depth — varies with the kind 
of metals which are being cut. A very small drill can cut .02 inch 
per revolution in cast iron; a large one can cut no more than .005 inch. 

Lubrication. For cutting malleable iron or steel the drill must 
be continually flooded with oil, while in cast-iron, aluminum, and brass 
drilling, the cutting is performed dry. 

Standard Threads. Tapping is that process of cutting on the 
walls of a drilled hole a series of threads into which a screw is to be 

Fir 31. Section of V-Thread 

fig. 32. Section of United State* > 
Standard Thread 

fitted. In practically every instance in motor-car practice, the 
standard taps and drills specified by the Society of Automobile 


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Drill Sizes for Standard Threads 


No. or 

Size op Drill 


No. op 

Size op Drill 









































































































































The above sizes give an allowance above the bottom of the thread on sizes 
Ji to 2, respectively, varying as follows: f or V-threads, .010 inch to .055 inch; 
for U.S.S. and Whitworth threads, .005 to .027 inch. 

These are found by adding to the size at the bottom of the thread one- 
quarter of the pitch for V-threads and one-eighth of the pitch for U.S.S. and 
Whitworth, the pitch being equal to 1 inch divided by the number of threads 
per inch. 

In practice it is better to use a larger drill if the exact size called for cannot 
be had. 

Engineers, Table II, will be used. Drill sizes of U.S.S., V-Standard, 
and Whitworth threads are given in Table III. 

The V-thread is shown in Fig. 31. The U.S.S; thread, Fig. 32, 
is the same as the V-type except that the tops are cut off and the roots, 
or bottoms, of the threads are filled in. It is more cheaply produced 
than the V-thread and does not cut so deeply into the stock, leaving a 
stronger root. In the Whitworth, or English Standard threads, the 
tops of the threads are rounded off and the roots are concave. In the 
S.A.E. Standard thread the U.S.S. principle of construction is used. 

Taps. The tools used to cut internal threads is known as a tap, 
external threads being cut with a die. There are hand taps and 
machine taps. The difference is principally in the shank. Hand taps 
have round shanks which are milled square on the end to receive the 
tap wrench. Three types of taps, called the taper, plug, and bottom- 
ing taps, Fig. 33, generally constitute a set. 


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Taper Tap. The taper tap has straight sides on the point end 
for a distance of one-fourth the diameter of the tap. The teeth at the 
shank end are parallel for a length equal to the diameter of the tap. 

Fig. 33. Typea of Hand Taps: Left— Taper Tap; Center- 
Tap; Right— Bottoming Tap 
Courtesy of Wiley & Russell Manufacturing Company, 
Greenfield, Massachusetts 


The teeth between these parallel teeth and the straight sides are 
tapered. This gives a graduated cutting depth for the teeth, the front 
teeth cutting less stock than the back. This tap is best suited for 
starting a thread, but 
unless the hole goes 
entirely through the 
piece that is being 
tapped there will, of 
course, be a space in 

the bottom of the hole Fi « **- Wiley A IWe11 Pi P° Ta » 

equal to one-fourth the diameter of the hole which will not be threaded. 
Plug Tap. The plug tap is most commonly used. It has three 
teeth on the end, tapered off so that while useful to start the thread, 
they will bottom a hole sufficiently to take a bolt with a tapered or 
round end. 


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Bottoming Tap. The bottoming tap is useful to finish out the 
thread started by a taper tap when the hole does not go entirely 
through the piece. 

There is frequent use in garages for pipe-plug taps, Fig. 34. As 
will be seen, they are more stocky than bottoming taps, and, of course, 

fig. 35. Threading Die Holder , 

have a taper throughout the surface of the cutting area to take care of 
the taper threads required by a pipe plug. 

Tapping Process. It must be remembered in using taps that, 
because of the nature of the work they are called upon to do, they are 
tempered hard and the cutting edges are very brittle; they must, 
therefore, be handled with great care. In hand tapping the process 

Fig. 36. Two Forma of Adjustable Dies; Left— Card Die with End Taper 
Screw; Right — Wiley and Russell Die with Side Taper Screw 

simply cannot be rushed; the tap must be turned slowly forward 
about half a turn and then back, advancing the wrench a little each 
time with an even stroke. As previously mentioned, a wrench must 
be used which fits over the square end. The pressure of both hands 
operating the opposite handles of the wrench must be even. 

Dies. There are two kinds of dies. One is the split type which 
requires several settings before the thread is completed and the other 


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which completes the work in one operation. The first kind is shown 
in Fig. 35, the assembly consisting of a stock or wrench in which the 
cutting die is held. These dies, for a specified size, may be opened up 
until the cutting edges will slide over the work and then, when fully 
closed, will give the completed thread of the correct dimension. 

Dies which complete the thread in one operation are made adjust- 
able for wear. They are made up in a solid round piece with one side 
cut away with a slot, as shown in Fig. 36, so that wear may be taken 
up by means of a taper-set screw. 

Oil should always be used in abundance on taps or dies. When 
one is threading steel or malleable iron, it is well to turn the die back 
after every three or four turns forward. 

In cutting threads with taps and dies in the lathe, the speed 
with which the tools may be operated is a very important considera- 
tion. Cast iron, brass, and aluminum can be threaded at a much 
higher speed than steel, but a tap or die must not be run as fast as a 
drill. A speed of 10 feet per minute in hard stock is a fair average. 

Function of Reamer • Reamers find their place in the production 
of round, straight, and smooth holes, uniform in diameter, as required 

Fig. 37. Solid Hand Reamer 

in the construction of accurate machinery, requirements which a drill 
cannot always be relied upon to meet. The reamer is a sizing tool 




Fig. 38. Expanding Reamer and Arbor 

having two or more teeth either parallel or at an angle with each 
other, the latter forming what is known as a taper reamer. These 


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Fig. 39. 

of Three-J 

Diagram Showing Action 
ree-Lipped Rean 
Irregular Hole 

Reamer in 

teeth may be either straight or spiral, a spiral tooth producing a 
shearing cut and a straight tooth a square cut. 

The construction of reamers divides them into two general 
classes — solid, and adjustable, or expansion, types. A solid reamer, 

Fig. 37, has a shank and teeth made from 
a single piece of tool steel. All taper 
reamers come under the solid class. The 
expansion reamer is a built-up tool, the 
usual form consisting of a shank and head, 
with an expanding arbor passing down 
through the center, Fig. 38. As adjust- 
ment to compensate for wear only is 
attempted, the amount of expansion is 

Number of Teeth. Number, form, 
and spacing of teeth are important con- 
siderations. Reamers having fewer than five teeth are not to be 
used where an accurate cylindrical shape is desired. A reamer 
having three teeth cannot be depended upon to produce round 
holes, inasmuch as any irregularity in the hole being reamed affects 
the cutting of the tool. For example, suppose a depression A, Fig. 
39, exists in the drilled hole; if tooth B comes to this point and drops 

in, the cutting of C and D is decreased, thus 
producing a hole that is not round. The 
same effect to a lesser degree is shown in 
Fig. 40. When the cut is relieved at A, 
the pressure of the cut C will crowd the 
tool toward E. Since the pressure of the 
cut at B and D balance each other, any 
decrease of the cut at C causes an increase 
at D, and B and C will overbalance 1), 
the body of the reamer moving an appre- 
ciable distance toward E. With five or 
more teeth this effect practically disap- 
pears. The more cutting edges, the more smoothly will the reamer 
work. The construction of adjustable reamers does not admit of as 
many teeth as can be formed on a solid reamer, yet the advantage 
of adjustability to a certain extent offsets this. 

Fig. 40. Diagram Showing Action 

of Four- Lipped Reamer in 

Irregular Hole 


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Where reamers have a number of teeth equally spaced, they do 
not produce so good results as those having an odd number of teeth. 
In the former, the teeth fall opposite each other, causing greater 
tendencies to vibration, and in the case of reaming irregular holes, 
the greatest cut will be carried on two opposite teeth. With an odd 
number of teeth the greatest cut must be carried on at least three 
teeth. Extensive use of reamers having an even number of teeth 
irregularly spaced is common. This gives practically the same effect 
as having an odd number of teeth. 

Clearances. Grinding of the clearance on top of the tooth is an 
important point in the construction of a reamer. The clearance 
should be sufficient properly to relieve the cutting edge, as shown in 
Fig. 41. If too great a clearance is given, the tooth will be weak and 
chatter in the work. As 
is frequently produced, 
the cleared surface is 
slightly concave, the 
amount depending upon 
the diameter of the emery 
wheel used in grinding it. 
As a plane surface is 
desirable, a wheel of 
large diameter which 
gives approximately such 
a surface should be em- 
ployed, or better still, the face of a cup emery wheel which gives a 
straight clearance. 

Clearance Angle. Clearance angle will depend largely on the 
distance the axis of the emery wheel is set back of the axis of the 
reamer. In no case must the wheel come in contact with the front 
face of the tooth being ground on the one next behind, and the guiding 
finger which steadies the reamer must always bear against the front 
face of the tooth being ground. When the diameter of the reamer is 
large and the pitch of the teeth so small that the necessary clearance 
cannot be given except by using too small an emery wheel, the wheel 
can be mounted on an axis at a considerable angle to the axis of the 
reamer. This produces a plane surface, but because of the wear of 
the emery wheel, it is not so satisfactory as the use of the cup wheel. 

Fig. 41. Diagrrjn Showing Method of Grinding 
Reamer for Clearance 


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The wheel must be so placed as to cut its entire width, otherwise it 
will be grooved and the cutting edges of the tooth rounded off. 

Characteristics of Hand Reamings. Reamers for hand use are 
made in two lengths, what is known as the short reamer being con- 
siderably shorter both in the flute and in the shank than the regular, 
or jobber's, reamer. The diameter of the point is about Vr inch under 
size, the tool tapering to exact diameter at about one-fourth of the 
length of the tooth from the point. The remainder of the teeth are 
ground nearly parallel, the diameter of the shank end being from .0005 
to .00075 inch small. This slight taper counteracts the tendency 
that all reamers have to ream a hole slightly over size at the top, 
which is due to the tool remaining longer in contact with the wall of 
the hole at the top than at the bottom. The limit of error allowed in 
their manufacture does not exceed .00025 inch. 

Kinds of Reamers. The spiral-fluted reamer always is cut with a 
left-hand spiral. It gives a smooth shearing cut and is especially 

Fig. 42. Reamer with Inserted Blades 
Courtesy of Brown and Sftarpe Manufacturing Company, Providence, Rhode Idand 

valuable for machine reaming on centers as it does not tend to draw 
into the work and off from the center. They are also made in shell 
and taper form. 

A fluted chucking reamer with a taper shank is not unlike a hand 
reamer. The teeth are short and slightly tapered at the point, which 
facilitates starting when used against the dead center of a lathe. 

The three-flute chucking reamer has a long shank, and the fluted 
portion is ground cylindrically true and is especially adapted to the 
reaming of deep-cored holes. 

Those classes of adjustable-blade reamers in which each blade is 
set out independently, Fig. 42, should be reground after each adjust- 
ment, as it is almost impossible to set the blades out equally. In 
using a reamer it should be turned continually forward. Never turn 
it backward for withdrawal, as this is likely to injure the tool. Oil 
should be used freely in reaming steel or wrought iron. Cast iron 
and brass are usually reamed dry. A small amount of oil, however, 
frequently improves the quality of work in these metals. 

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Determining Amount of Taper. In order to set the slide rest 
of the lathe at the proper angle for boring or reaming any degree of 
taper, measure the diameter of the circular rest-seat, Fig. 43, and 

Fig. 43. Compound Tool Slide Rest 

describe a circle of that diameter on a flat surface, marking the center 
of the circle and drawing a radial line AH, Fig. 44; mark off on AH a 
distance AB equal to the diameter of the small end of the taper hole 
to be bored and draw the line AG at right angles to AB and of a 
length equal to the length of the taper to 
be bored. Draw GB parallel to AB and 
of a length equal to the diameter of the 
larje end of the taper. Connecting D 
an 1 B, the distance EF measured on the 
cii cumference of the circle between the 
lir es will equal the amount that the rest 
in ust be swiveled to cut the desired taper. 
Reamers and Taper Pins Available. 
The Pratt & Whitney Company makes 
standard taper reamers with a taper of 
tV inch per foot and diameters from J inch 
up; also 4-inch length of flute up to 2 
inches in diameter; finally they make 
18-inch length of flute, diameters advanc- 
ing by 16ths and 32nds. The Pratt & Whitney standard taper-pin 
reamers taper £ inch per foot and are made in fifteen sizes. 

Fig. 44. Diagram for Determining 

Slide Rest Setting to Give 

Certain Taper 


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Brown & Sharpe make eighteen sizes of tapers ranging from 0.20 
inch to 3 inches in diameter at the small end; taper 0.5 inch to 1 
foot, except the number 10, which is 0.5161 inch per foot. 

The Jarno taper is 0.05 per inch, or 0.6 inch per foot. The 
number of the taper is its diameter in tenths of an inch at the small end, 
in eighths of an inch at the large end, and the length in halves of an 
inch. Thus, No. 3, Jarno taper is l\ inches long, 0.3 inch in diameter 
at the small end and f inch in diameter at the large end. 


Hand keyseating is that process of cutting a groove into a piece of 
metal into which a key will fit accurately. The need of accuracy 
in keyseating is the great drawback to the hand method inasmuch as it 
is a tedious job to cut a true seat with a chisel. 

Keyseating Process. The roughing out of the keyseat is done by 
chipping, a process already described. The first thing to determine 
is the size of the keyseat, and this is obtained from the S.A.E. table of 
standard sizes of keyseats, Table IV. It is well to have a chisel with a 
cutting surface about \ inch smaller than the width of the keyseat to 
be cut, although with a large keyseat a smaller chisel will do the work 
but with somewhat more cutting. A cape chisel, Fig. 4, is the tool 
used for keyway cutting. 

Laying Out the Keyway. The next operation is to very carefully 
mark off the keyway with scratched lines or chalk, the distance 

between the lines to be from 
iV to Tt inch less than the 
width of the key. Use these 
lines to guide the chisel and 
cut the keyway to a depth 
approximately- within -fa inch 
of the depth of the finished 
keyway. One must always 

Fig. 45. Chipping Keyseat in Round Shafting j^^ sufficient stock Qn the 

sides and bottom of the keyway for an accurate finish filing. 
Chipping. The work is held in a vise, and the chipping is done 
by grasping the chisel firmly with the left hand, holding the cutting 
edge to the work and striking the head of the chisel with the hammer, 
Fig. 45. The eyes must be kept on the cutting edge of the chisel to 


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Standard Sizes of Keyseats 

For straight keys, height of keyseat =»D 

For feather keys D = }A 

Keyseat in shaft same depth as D in small end 

Standard Taper =»1 inch per foot. 

watch the progress of the work. The beveled side of the chisel is the 
guiding surface and this should be held at a very slight angle with 
the surface of the work that is being cut. Of course, to increase or 
decrease the amount of the cut, it is only necessary to raise or lower 
the chisel. If the hand is carried too low, the tool will run out before 
the end of the cut; while if the hand is carried too high, the chisel will 
gouge into the stock and make the progress of the work slow. In 
steel, malleable iron, and cast iron, the depth of the cut should vary 
from tV to | inch, but should never be greater than the latter figure. 

Chipping Malleable Iron and Steel. When chipping malleable 
iron or steel, one should keep on the work bench a piece of waste or 
cloth saturated with oil. After each complete cut is made through the 
work, the chisel should be rubbed in this waste or cloth. This lubri- 
cates the cutting edges and prolongs the life of the chisel. 

Finish Filings. It is in the finish filing that the greatest accuracy 
must be observed. It is not advisable to attempt cutting keyways to 
an accurate size by the use of inside calipers or other measuring instru- 
ments; it is best to have at hand the key which is to be fitted into the 
keyway. As the work of filing progresses, test the key in the keyway 
at frequent intervals. The sides and bottom should be filed at the 
same time, and it is quite important that the proper width of file be 
obtained. One should so file the keyway that the bottom and sides 
will be cut down to the proper size at about an equal rate. The key 
mu?t not be a loose fit but a press fit within the slot. 


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Woodruff Keys. Although it is a very difficult and time-consum- 
ing task, it is possible to cut Woodruff keys with a chisel. These are 
"half moon" keys, the radial surface serving to lock the key into the 
seat after the matching keyways are fitted over it. The cut and try 
process is the only method to use in fitting Woodruff keys. Have the 
key at hand and chip the concave keyway, using the key as a pattern. 


Brake Linings. Types of Rivets. Rivets used for brake linings 
are of three kinds, the flat head, countersink, and split rivets, Fig. 46. 
The former is headed like an ordinary nai 1 and may be procured 
in a number of head-diameter sizes. The countersink rivet has a 
head which is flat on top and tapered underneath to fit a countersunk 
hole. The split rivet has a countersunk head with a split shank 
to permit the bending over of the ends like a cotter pin. 

The split rivet with countersunk head is the easiest rivet to 
handle in relining brake bands. It is not well to use the old brake 

lining as a pattern for a new one, 
but a new one should be cut. 
Wrap new lining around the band, 
being sure that it is tight all 

Fi«. 46. Types of Rivets for Brake Linings around the Surface and CUt it off 

the right length, allowing no overhang. 

Riveting the Lining. Fasten the band in the vise with the 
convex surface up and one end within the jaws of the vise. Procure 
a drill the size of the rivet holes in the brake band. With a sharp 
instrument prick the brake lining through the two end rivet holes 
and drill the lining through. Then countersink these holes so that 
the top surface of the rivet is very slightly below the top of the 
lining. Do not countersink so deep that the rivets will pull through. 
Now insert the copper rivets through the lining and brake band. 
If split rivets are used, proceed as follows: Select a bolt of such a 
size that it will give a firm seat for the head of the screw and fasten 
it in the vise with the threaded end up. Place the rivet head 
against the end of the bolt, spread the two ends of the split rivet 
with a screwdriver, and then pound them firmly against the band 
with a hammer. If solid head rivets are used, the head should be 
riveted solidly with the round end of a machinist's hammer. 

■eJLh *rm* ^£&fc*» 


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Proceed around the band with consecutive rivets, keeping the 
lining stretched firmly at all times. 

Clutch Facings. The most common cause of faulty cam-clutch 
action is some defect of the leather facing. When one has determined 
that the facing needs replacement, he is confronted with the propo- 
sition of installing a new leather, and here is where one must have 
a working knowledge of the proper methods of riveting. 

Proper Clutch Leathers. Just a word about clutch leathers. 
If one decides that a leather must be replaced, then it is the best 
plan to replace it with a new one from the factory of the maker of 
the automobile. Of course, it is not a difficult matter to cut a clutch 
leather (see instructions in Gasoline Automobiles, Part IV), and if 
the garage has a stock of good clutch leathers, then cutting your 
own is the simpler plan. One difficulty, however, is that the quality 
and thickness of the leather you purchase may not be suited at 
all to the clutch upon which it is to be put. The factory leathers 
are of a material and size specified by the engineers of that factory 
and are the right ones to use. 

Preparing the Leather. Before riveting the new leather in place 
it should be made as pliable as possible by soaking it in neat's-foot 
or castor oil. This soaking should be carried on until the oil has 
penetrated the leather from surface to surface. Do not soak the 
leather in water with the idea that it will fit more tightly over the 
cone; there is a big chance of its shrinking too much and pulling 
away from the rivets. 

Putting Leather on Clutch. It is best to purchase the leather 
in endless form, that is, sealed at the ends so that it will fit perfectly 
over the cone. First, place the leather on the cone with one side 
flush with the large diameter of the cone. Then pry the leather on 
until it is evenly fitted to the metal surface. If the leather hangs 
over the small-diameter edge of the cone, it is not on far enough and 
should be pried farther over the edge of the taper. No trouble should 
be experienced in fitting the leather by the use of the hands only. 

Riveting Process. The holes in the leather should be countersunk 
deep enough so that the rivet heads will be below the surface and 
yet not so deep that there will be danger of the leather pulling 
away from the rivets. Incidentally, after the leather facing has 
been applied, it is well to nib off the high spots of the leather with 

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Proportions for Riveted Steel Plates with Iron Rivets 






Thickness of plate 

Diameter of rivet 

Diameter of rivet hole . 
Pitch — single riveting. . 
Pitch — double riveting. 














the edge of a piece of glass. Insert a rivet through one of the counter- 
sunk holes in the leather, which, of course, matches up with a hole 
drilled through the clutch cone. Flat-headed countersink rivets of 
copper should be used, the rivets being long enough to project & 
inch through the clutch cone. Place a bolt with the head ground 
slightly flat in a vise, the head end being up. Hold the rivet in the 
clutch leather against the bolt head and hammer a head on the 

rivet with the round end of a 
ball-peen hammer. Duplicate 
this operation for each of the 

Cold-Riveting Metals. 
Rivets are used to hold together 
two or more pieces of sheet 
metal and are employed in the 
assembly of frames, the sup- 
porting of spring hangers, etc. 
Table V gives the proportions 
for riveted joints in steel 
plates with iron rivets. Cold 
riveting can be applied to work 
where accuracy is not a requi- 
site and the rivets are of small 

Fig. 47. Eaaily-Made Type of Rivet Set ^ Rg ; n sheet metftl WQrk 

Hot-Riveting Metals. For htft-riveting work there are two 
general classes of rivets used : countersunk rivets and flush rivets, 
Fig. 47. Flush rivets are used to support the spring hangers to the 
frame and in riveting cross-members to the frame, etc. Countersunk 
rivets are used cold in brake lining facing and clutch facing, as 
previously described, and in joining pieces where clearance is a factor, 
as in riveting the ring gear to the differential case flange. 


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Rivet Set. In heading large rivets, it is always advisable to 
use a rivet set, and in the case of riveting the ring gear to the differ- 
ential case flange this tool is essential. The rivet set is a tool with 
a spherical depression in the end. When this spherical depression 
is applied to the shank end of a rivet and the rivet set is hammered, 
the end of the rivet will be headed over in a nicely rounded head. 
It is the only way that accurate riveting can be accomplished. 

Installing New Ring Gear. Usual rivet sizes for use in fastening 
the ring gear to the differential housing flange are J, i^, and f inch. 
The rivets used are round-headed or countersunk and are made of 
iron. To do a good job of installing a new ring gear proceed as follows : 

Removing Old Gear. The first thing to be done is to remove 
the old gear. This is done by cutting off the rivet heads with a sharp 
chisel in the manner show r n in Fig. 3. If the rivet is countersunk, 
the head may have to be drilled out to remove it. After the gear 
is off, go over the surface of the differential housing flange with a 
file — especially over the rivet holes — to remove any b.urrs or irregu- 
larities in the metal which would cause an untrue seat and thus 
throw the ring gear out of line. Do the same thing on the face of 
the ring gear which is to fit against the differential housing flange. 

Heating Rivet. Although this job may be done by cold riveting, 
the hot method is a stronger and truer assembly because it permits 
more accurate seating and firmer fastening of the rivets. The 
rivets should be of such a length that they will extend beyond the 
flange a distance equal to one and one-half times the diameter of 
the rivet. The rivets should be placed through the flange and gear 
in consecutive order but alternating in direction; that is, the head 
of one rivet should go through in one direction and the head of 
the rivet next to it in the other direction. 

One of the best methods of heating the rivets is by means of 
an oxy-acetyline flame, although they may be heated in a forge as 
well. The rivets must be put into the holes red hot, as they are 
more easily headed over, and, in addition, the shrink in the rivets 
as they cool draws the pieces closer together. The constant hammer- 
ing in forming the head thoroughly fills the hole. 

Making Rivet Set. If one does not desire to purchase a rivet 
header, it is not hard to make one. One ofohe simplest ways is as 
follows: Procure a bar of round steel about twice the diameter of 




the head of the rivet. Fasten one of the rivets in a vise with the 
shank within the vise and the under side of the head flat against the 
top of the vise jaws. Now heat one end of the bar to a w T hite heat 
and drive the heated end against the round rivet head, thus making 
a depression in the end of the bar, Fig. 47. It will probably be 
necessary to reheat the bar two or three times, using a new rivet 
each time, to get the depression deep enough. This depression should 
be of such depth as to take in the entire head of the rivet. Another 
method is to drill the depression into the end of the bar, thus giving 
a V-shaped depression. Such a depression will serve nearly as well 
as the round one for the work at hand. 

Heating the Rivet. It is now assumed that one has rivets, 
red hot, in the forge, a rivet set of the proper size, and that an anvil 

or a block of steel or iron, 
upon which the riveting 
may be done, is available. 
Extract one of the rivets 
from the forge with the 
tongs and insert it 
quickly into the rivet 
hole. It is imperative 
that the work be done 
quickly, so that the final 

Fig. 48. Section of Rivets in Place . , . . 111 

heading is completed be- 
fore the rivet has had a chance to cool. The head of the rivet is dropped 
down against the anvil or block of iron or steel. With the assembly 
held firm against the anvil or block, place the rivet set over the 
shank of the rivet and hammer with quick light strokes against the 
other end of the rivet set with a fairly heavy machinist's hammer. 
Convenience and quick work demand that this be made a two-man 
job, one to hold the work and the other to do the riveting. In 
shaping the head, oscillate the rivet set in the hand so that the head 
will be evenly rounded on all sides. A properly shaped rivet head 
should be very nearly the same shape as the head, which was a part 
of the rivet in its original form, as shown in Fig. 48 A. A well-rounded 
head is stronger than one which is more or less flat and which spreads 
over a larger area. In I\ig. 48 B is shown the section of a countersunk 
head joint. 


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Fig. 49. Modern Motor-Driven Forge 
Courtesy of Canedy^Otto Company, Chicago, Illinois 


Forging Equipment. Forges. Many of the 
jobs in a repair shop require the use of a forge, 
two kinds being necessary for all well-equipped 
shops. Forging and welding are easily cared for 
by the power-driven blower forge, Fig. 49. 
This type of forge is made of steel and the 
medium size is best for automobile repair shop 
work. For brazing, melting babbitt metal 
hardening, tempering, annealing, and heating 
soldering irons, it is best to use a gas forge 
that takes its air from the tank of the air- 
compressor outfit and its gas from the regulai 
city or town mains. Portable gasoline forges 
Fig. 50, are obtainable and work equally well 
It is well to have also a small hand torch, Fig 
51, for use in smaller brazing or soldering jobs 

It is well to set up these two necessary Fig. 50. Doubie-Jet Braier 

•1111 1 rru 1 1 Courtesy of Turner Bras* Works, 

forges with a bench between them. The bench Chicago, Illinois 


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should have a large drawer and a good vise attached to it, and will 
be found useful both in brazing and soldering processes; the drawer 
can be divided into compartments, one to hold the blacksmith tools 

and the other the solder- 
ing irons and sheet-metal 
tools. The vise will come 
into use innumerable 
times at either forge. 

Fig. 51. Hand Gas Torch for Bracing Took. The remain- 

ing equipment is simple. A medium size anvil, Fig. 52; two sledge 
hammers, medium and heavy; three, or perhaps four, forge hammers; 
tongs for holding round, flat, and irregular work; tools for cutting off 
material, both hot and cold; and finally flatting and swaging tools. 
Melting ladles can be placed over either coal or gas flame, and either 
forge can be used in melting the antifriction metals used in lining 
bearing boxes. 

Blacksmith ing Repair Outfit. A complete blacksmithing outfit 
that is adequate for ordinary repair shop work can be purchased 
for approximately $50. This will give a forge that uses coal as a 
fuel, a vise, a set of taps and dies, anvil, drill press, hammers, drills, 
tongs, wrenches, and a few small tools. Some of the tools that apply 

strictly to horseshoeing can be 
applied to the repair of auto- 
mobiles. These consist of a 
farrier's hammer, knife, and 
pincers. All of the other tools 
mentioned apply to general 
metal work. A post drill will 
be found very practical for 
shops not provided with power. 
As complete sets of drills 
usually accompany the post- 
drill outfit, it is not necessary 

FfciB. Anvil Fastened to B.ook t0 St ° Ck U P 0D & ^"^ ° f 

tongs, for these can be made 
best to suit the purpose for which they are to be used. 

Electric or Gas Furnaces. If the shop is a large one, there 
probably will be considerable tool dressing that will require heat- 


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treating of various parts, and an electric furnace may be procured 
to handle this class of work. With a furnace of this kind, the amount 
of heat may be regulated within close limits, and temperatures may 
be reached that are sufficiently high for hardening, carbonizing, or 
annealing any pieces within the range of the furnace. It is 
questionable whether a furnace of this kind would be practical, 
except for large shops where there is much oT this class of work to 
be done. Furnaces of the gas- or oil-burning types, Fig. 53, are 
probably more serviceable and less 
expensive than the electrically heated 
form. Welding is a very useful repair 
process in automobile work and it will 
be found fully treated in another 

Heat Treatment. Since there is 
an almost universal use of high-grade 
alloy steel in automobile construction, 
it is quite necessary that the repair 
man have some knowledge of heat 
treatment of the various metals. It 
must be known that metals of this 
character cannot be machined unless 
they are annealed and are of but 
little greater value than the ordinary 
machinery steel parts if they are not 
properly heat-treated to bring out the 
physical characteristics desired after 

* . . Fig. 53. Simple Gaa Furnace 

fabrication. Courtesy of American Gas Furnace Company, 

Tempering Steel. The simplest 
method of tempering steel is the old-fashioned method of only partly 
cooling the tool when quenching it, then quickly withdrawing it, pol- 
ishing off its working surface, and letting the heat which remains in 
the tool produce the required temper as judged by the color. When 
first quenched, the point of the tool is the coolest and, on with- 
drawing it, the heat in the balance of the tool heats up the point, 
changing its color from light straw to deep straw, then light brown, 
darker brown, light purple, dark purple, dark blue, light blue, and 
finally blue tinged with green and black. When black appears, the 


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temper is gone. When the color desired is reached, the tool should 
be completely quenched. 

The following tabulation shows the temperature in degrees 
Fahrenheit at which steel assumes certain colors. 

Degrees Color 

430 Very light straw 

450 Light straw 

470 Dark straw 

490 Very dark straw 

500 Brownish yellow 

520 Yellow tinged with purple 

530 Light purple 

550 Dark purple 

570 Dark blue 

The modern method of tempering is by means of a furnace, 
as shown in Fig. 54, an oil bath being heated by an oil or gas flame 

to the proper temperature, as 
indicated by the thermometer, 
and the tools immersed in the 
bath. When they have reached 
the same temperature, they are 
lifted out and quenched in a 
hardening bath. The use of 
such a furnace makes the tem- 
pering of the shop tools more 

Hardening Steel. As it is 
necessary to maintain the steel 
in the state it was at the mo- 
ment quenching began, the 
quenching bath is a very im- 
portant part of the process of 
hardening. The better the 
bath, the more nearly per- 
fection is attained. 

Various baths are used for 
cooling steel when hardening, 

Fig. 54. Typical Tempering Furnace on aCCOUnt of the different 

Courtesy of Strong, Carlisle and Hammond , , * . . ., .,, 

Company, Cleveland, Ohio rates at Which they COOl the 


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heated metal. An oil bath is used when the steel is wanted tougher 
and not excessively hard, as the oil cools the steel more slowly than 
water. Brine or an acid bath is used when the steel is wanted very 
hard, as they absorb heat more rapidly than water. For excessively 
hard work, mercury or quicksilver is sometimes used, as it absorbs 
the heat very rapidly. 

Self- Hardening Steel. Self-hardening steel is used to a large 
extent in modern practice for lathe tools, much being used in the 
shape of small square steel blades held in special holders, as 
Fig. 55. Self-hardening steel, as its name indicates, is almost 
self-hardening by nature; generally, the only treatment that is 
required to harden the steel being to heat it red hot and allow it 
to cool. Sometimes the steel is cooled in an air blast or is dipped 
in oil. It is not necessary to draw the temper. The self-hardening 
quality of steel is given to it by the addition of chromium, 
molybdenum, tungsten, or one of that group of elements, in addition 
to the carbon which ordinary tool 
steel contains. High-speed steel 
is lower in carbon. 

Self-hardening steel is com- 
paratively expensive, costing from m 55 Tool u _ Hardening 
40 cents and upward per pound, steel *""** 
some of the more expensive grades costing $1 or so. However, when 
in use, self-hardening steel will stand a much higher cutting speed 
than the ordinary so-called carbon steel, and for this reason it is 
much more economical to use, although its first cost is higher. 

Self-hardening steel cannot be cut with a cold chisel and must 
be either cut hot or nicked with an emery wheel and snapped off. 
Great care must be used in forging it, as the range of temperature 
through which it may be forged is comparatively slight, running 
from a good red heat to a yellow heat. Some grades of self- 
hardening steel may be annealed by heating the steel to a high heat 
in the center of a good fire and allowing the fire and the steel to cool 
off together. Steel which has been annealed in this way may be 
hardened by heating to the hardening heat and cooling in oil. 

Hardening High-Speed Steel. High-speed steel has a much 
higher critical temperature than carbon steels. A temperature of 
about 1350° to 1600° F. is sufficient for carbon steels in general. 



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High-speed steels require heating from 1800° to 2300° F. and to 
be cooled in oil such as machine, fish, or linseed. 

Bending Rods. If a piece of hard tubing is to be bent, it must 
first be annealed, otherwise it is likely to break. If the piece to be 
bent is thin-walled tubing, it will collapse. Occasionally, the bending 
of a moderately thick-walled piece of tubing can be accomplished 
without heating or filling, although it always is best to fill the tubing 
before attempting to bend it. If the interior is made solid, or nearly 
so, with some substance and if the tubing is properly heated and 
of the right temper, it can be bent to a curve of small radius without 

damaging the walls of the tubing. 
It is poor policy to avoid filling 
the tube by the use of a vise or 
wrench, or hammer and anvil for 
bending, as the walls of the tube 
will suffer and the appearance of 
the finished work will be unsat- 
isfactory. There are several 
methods of filling tubing that give 
good results. Some molten sub- 
stances can be poured into the 
tubing, such as resin for thin 
copper, and brass or lead alloy 
in steel tubing. The fillers can 
be removed by heating the tubing 
after the bend has been made. 
Some make use of a steel rod 
when the bending describes a part 
of a circle, as the filler rod takes 
the same curve as the tube and thus comes out easily. When many 
pieces of about the same size of tubing are to be bent, it can be very 
satisfactorily accomplished with a grooved jig, as shown in Fig. 56. 


Definition of Terms. In designing or cutting gears, it is quite 
essential that the terms as applied to this practice be clear to the 
operator. The nomenclature of gears and their measurements are 
such that only by diagram, shown in Fig. 57, together with the 

Fig. 56. Grooved Jig for Bending Pipe 


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following explanation, can one obtain a clear conception of the 
various measurements: 

Pitch Diameter. The pitch diameter is the diameter of the 
pitch circle. 

Addendum Circle. The addendum circle has the same diameter 
as the outside diameter taken over the points of the teeth. 

Dedendum Circle. The dedendum circle is known, also as the 
root circle and is the circle at the bottom of the teeth. 

Pitch. Pitch is the distance from the center to the center of 
the teeth when measured on the pitch circle. Measured in this 
way, it is called the circular pitch. 

Fig. 57. Names of Tooth Parte 

Face. The face of the tooth is that part of the curve outside 
of the pitch circle. 

Flank. The flank of the tooth is the portion of the curve within 
the pitch circle. 

Thickness. The thickness is the width of the tooth, taken as 
the chord of an arc of the pitch circle. 

Space. The space is the distance . between adjacent teeth, 
measured as the chord of an arc of the pitch circle. 

Method of Design. In designing gears two methods are 
employed, one known as the fixed-pitch method and the other 
as the diametral-pitch method. The latter perhaps is the more popular 
since the first involves some tedious calculation, but in the event 


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that one may wish to apply it, it is well to explain the process and 
what it means. 

Fixed-Pitch Method. It once was the practice to design gears 
on the basis of a fixed distance representing the teeth and this was 
usually based on the common fractions of an inch. Thus the desired 
number of teeth multiplied by the given pitch gave the circumference, 
and the distance, found in this way, divided by 3.1416 gave the 
diameter of the pitch circle. 

Let us suppose that the pitch is divided into fifteen parts, 
seven of which represent the thickness of the teeth and eight the 
width of the space. To find the length of the teeth, the pitch is 
divided into ten parts, of which seven represent the length of the 
teeth — three parts covering that portion outside of the pitch circle 
and four parts the length of it, one part being allowed for bottom 
clearance. Because of the tedious calculation involved in this 
method, mechanical engineers devised the diametral pitch method. 

Diametral-Pitch Method. The diametral-pitch method desig- 
nates the pitch by a number instead of giving the length of the pitch 
in inches. This number indicates the number of teeth for each inch 
of diameter of the pitch circle. Thus, if the diametral pitch is 6 
and the diameter of the pitch circle is 10 inches, the gear will have 
6 times 10, or 60 teeth. Also, if we know that the pitch is 6 — or as 
usually expressed "6-pitch" — and the gear has 60 teeth, the pitch 
diameter is 60-*- 6, or 10. If the gear has 60 teeth and the diameter 
of the pitch circle is 10 inches, the pitch is 60-*- 10, or 6-pitch. 
Three simple rules cover the diametral-pitch method: 

(1) Multiply the diameter of the pitch circle by the diametral 
pitch to get the number of teeth. 

(2) Divide the number of teeth by the diameter of the pitch circle 
to get the diametral pitch. 

(3) Divide the number of teeth by the diametral pitch to get the 
diameter of the pitch circle. 

Proportions of tooth parts are determined by rules quite as 
simple as those of the pitch. These are as follows: 

(1) The addendum is equal to one inch divided by the diametral 
pitch. For example, the addendum on a 6-pitch gear will be \ inch. 

(2) The dedendum is equal to the addendum increased by the 
clearance y which is equal to yg the thickness of the tooth on the pitch circle. 

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Fig. 68. Proportions of Teeth of Different Diametral Pitches 


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Determination of the thickness of the tooth and the width of 
the space at the pitch line is not by the same rule as that given in 
the former method. In all accurately cut gears, the width of the 
space exceeds the thickness of the tooth only as much as may be 
necessary to permit the gear teeth to roll freely together and need 
not be over .03 of the circular pitch. In cut gears for ordinary 
purposes, this amount may be doubled, while in gears having cast 
teeth, it may be necessary to make it as great as 0.10 of the circular 
pitch, depending largely on the accuracy of the casting. That a 
clear conception may be obtained of the relative dimensions of 
spur-gear teeth of different diametral pitches, the gear teeth are 
shown in full size .in Fig. 58. These are the more common pitches. 
The larger ones are usually 1-, 1J-, 2-, 2£-, and 3-pitch. 


Best methods for doing work are constantly coming up in all 
shop work, and the success with which the desired end is attained 
depends largely upon the skill and judgment of the man in charge. 
A few examples of the questions likely to arise and suggestions for 
handling them to give the best solution follow. 

Peening. Stretching metal on one side of a piece of work is 
called peening. There is considerable difference between peening 
and bending. Let us suppose that you have a warped piece of 
metal to be straightened. If it were to be bent until it were straight, 
it could be placed on a block with the concave side down and struck 
with a hammer and driven down past the line of support. This 
strain would reduce it into an approximately straight line. However, 
this method could not be applied to a piece of metal with complicated 
outline for it would remain wavy. In peening to trueness such a 
piece as that previously mentioned, the piece is placed on an anvil 
with the convex side down and struck sharp blows with the peen 
of the hammer on the concave side, with the result that the metal 
is stretched at the point where the blow is struck. Working succes- 
sively over the whole surface results in the concave side being 
stretched so that it is equal in dimension to the convex side, and 
the piece becomes straight and remains so. Skillful use of the hammer 
will straighten almost any piece of thin metal. The same process 


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of stretching the metal is sometimes applied to a hole in a ductile 
metal which is too large. Possibly a screw has worked the threaded 
hole too large, but by peening the metal around the hole with a 
hammer and prick punch, the fit is made tight again. Such a method 
is not good shop practice but accomplishes a quick repair. 

Drilling Hard Metals. When a hole is to be drilled in a very 
hard metal, the drill must also be very hard and must be run at a 
relatively low speed. The drill must be forced against the metal 
with as much pressure as possible without breaking the point and 
an abundant supply of oil is necessary. A drill may be excessively 
hardened by heating it to a dull red in a charcoal fire and quenching 
it in mercury instead of in water to make the cooling more rapid. 
Nicking the surface of the metal with a cold chisel also will give the 
drill a start, and beneficial results are obtained by using turpentine 
in place of oil in some cases. Very thin chilled cast iron may be 
softened somewhat by placing a small amount of sulphur on the 
place where the hole is desired and then heating to a dull red. This 
should be done slowly, however. 

Avoiding Scale. When cast iron is being worked in a lathe or 
a planer, the point of the tool always should work beneath the scale, 
which is the outer shell that covers all cast iron as it comes from the 
foundry. This scale is very hard and brittle and if the edge of the 
tool is made to work in, or against it, the edge is soon dulled. When 
the tool works beneath the scale, raising the chip removes the scale. 

Pickling. All castings that are to be machined to dimensions 
that are only slightly less than those of the rough castings should 
be pickled or washed in a solution of sulphuric acid and water, 
which causes the scale to drop off in flakes and leave the metal bare, 
unprotected, and rusty. Either submersion or swabbing is effective. 
After being pickled the casting should be washed in a sal soda solution. 
A good pickling solution for this work is one part of commercial 
sulphuric acid to ten parts of water. 


Types of Machines. An arbor press is one of the most useful 
tools for an automobile repair shop. Arbor presses are available 


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in a number of forms. In the simplest type, the pressing medium is 
a rod which is forced down by pulling down on the handle which 
is counter- weighted on the opposite end. By a ratchet principle, 
the rod is held against the work while another stroke of the handle 
forces the rod farther down. When the handle is let up to the top 
of its stroke, the locking mechanism is released and the rod may 
be pushed up by hand. 

Fig. 59. Arbor Press for Automobile Work 

There is now on the market a universal press especially adapted 
for automobile work, Fig. 59. This machine has a capacity of 22 
tons and allows a 42-inch clearance for the work. It has two levers, 
one for high-speed work, geared 1000 to 1, and one for low-speed 
work, geared 2200 to 1. In the illustration, the mechanic is shown 
pressing off transmission gears with channel blocking, using the 2200 
to 1 leverage. The other attachments furnished with the machine 
are shown on the floor. 


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Uses of Arbor Press. V-Block. For automobile work, a useful 
part of the arbor press equipment is a V-block, shown on the floor 
beside the machine in Fig. 59. This block is a receptacle for a great 
many different kinds of stock. 

Handling Press Fits. In automobile construction, there are 
a great many parts which are a press fit into another part. A press 
fit differs from a sliding fit in that one piece must be forced into another 
for permanent location while those parts are performing their function ; 
with a sliding fit, one part is located within another so that it may be 
readily moved, as in a bearing. The arbor press easily handles 
press fits in replacement and repair. 

Where a shaft is a press fit within a gear, that shaft may be 
pressed into the gear by means of the arbor press. The gear should 
be located on the bed of the press. If it has a hub, the gear should 
be supported underneath as close to this hub as possible so 
there will be no danger of springing the gear. The shaft is then 
started into the hole; the screw or rod of the arbor press tightens 
down against it and presses the shaft into the gear. It is well to 
remember that the available pressure in an arbor press is enough to 
bend a sizable piece of steel, and with this in view, work should 
always be very carefully centered and, in the case of shafting, the 
shaft should be perfectly parallel with the sides of the hole it is 
about to enter. 

Removing Bearing Bushings. One of the biggest fields for the 
arbor press in. a garage is in the removal of bearing bushings. m There 
are a great many places about the car where bearings are pressed into 
their containers, a notable instance being in the springs. Bearing 
bushings may be very readily pushed out of springs with an arbor 
press. In most universal joints the steel bushings are pressed 
in with an arbor press and about the only satisfactory way they 
can be removed is to press them out with the same kind of a 

Straightening Parts. Another use for the arbor press is in 
straightening parts. In the modern automobile, practically all 
parts which take a considerable amount of strain are constructed 
from alloy steel. In order to properly prepare alloy steel for severe 
strains, it must be heat-treated in an accurately calibrated oven to 
a temperature averaging about 1500° F. Too many repair men make 

175 Digitized by 



the mistake of trying to straighten these heat-treated parts in a 
forge. Once they are heated in a forge, the value of the previous 
heat-treating is lost and it can only be put back into the metal 
again in a heat-treating oven. 

Furthermore, parts made of alloy steel which have been subjected 
to the heat-treating process, although capable of tremendous bending 
strains, may nevertheless be bent without harm to them providing 
enough pressure is applied. An arbor press capable of exerting a 
15-ton pressure can be used for straightening front axles, steering 
knuckles, and like parts. 

The arbor press may also be used for straightening tubing and 
cylindrical parts, such as torsion tubes and rear-axle housings. In 
doing this work, a screw press is superior to the kind where leverage 
alone is the pressure factor, because it permits more careful pressing. 
With an available pressure of 15 or 20 tons, it is a very easy matter 
to crack a piece of tubing or a cylindrical part, such as a torsion 
tube or a rear-axle housing, and great care should be exerted in the 
bending operation. 

Gear Pullers. Although the arbor press may be used for gear 
pulling, there is a simpler device, known as 'a gear puller. Where 
gears are fitted to small shafts, they are in a great number of cases 
made a press fit on the shafting. If one were to attempt to hammer 
the gear off, he would very likely either damage the teeth of the 
gear or bend the shaft. A gear puller will remove the gear without 
damaging any part of the assembly. It is a simple device consisting 
of a beam at the ends of which two arms are fastened with pins. 
These arms are constructed with hooks on the ends. Through the 
center of the beam is a thread cut for the purpose, and in this is a 
screw with one end shaped to a V and the other end squared to permit 
the application of a wrench. 

In operating, the hooked ends of the two arms are fastened to 
the back of the gear or pulley. Then the screw is turned down until 
the V-end fits against the center of the shaft on the opposite side 
of the gear or pulley to which the hooks of the arms are fastened. 
Screwing down the screw by means of a wrench will exert sufficient 
pressure to force the shaft out of the gear. 

Combination Gear and Wheel Puller. There is now an instrument 
on the market which is a combination gear and wheel puller, Fig. 





60. As will be seen, in this instrument the arms cross like a pair of 
pliers, and the upper ends of the arms have a number of holes drilled 
in them. A center block between the arms carries the thread for 
the screw, as well as a tapped hole on each side. Screws are passed 
through the drilled holes in the arms at various points and into 
the tapped holes of the center block, thus giving considerable 
variation in adjustment for the different sizes of work. 


Advantages of Grinding. 

Machine-shop grinding operations 
depend upon the abrasive or cutting 
qualities of stone, emery, carborun- 
dum and corundum, when suitably 
held and presented to the work. The 
use of solid grinding wheels has made 
it possible to attain many refinements 
in machine construction that would 
have been impossible without them. 
It has made it practical economically 
to finish hardened steel parts that 
could not possibly be machined with 
cutting tools in the lathe or the planer, 
and with the softer materials it has 
made possible smoother and truer 
surfaces than can be obtained by any 
other method. 

Types of Grinding. There are 
four principal divisions to grinding: hand grinding, tool and cutter 
grinding, cylindrical grinding, and surface grinding. The two latter 
classes are never required in repair work. 

Hand Grinding, Under hand grinding is included all the 
operations in which the work is held to the wheel by hand or with 
a rest, as in rough grinding, ordinary lathe-tool grinding, buffing, 
and polishing. The class of machine used for this work is of the 
simplest form, consisting of the wheel-carrying spindle mounted 
on suitable bearings on a substantial head or pedestal. Some machines 

Fig. 60. Combination Gear and Wheel 


Premier Electric Company, Chicago 


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of this character carry one wheel, others two. Adjustable rests 
are provided upon which the wwk being ground can be steadied. 
This class of grinders is designed for dry grinding of rough and 
heavy material, where the danger of overheating the work is negligible. 

If the work to be ground 
is tempered, or is likely to 
become over-heated, a grinder 
in which a supply of water 
is constantly on the rim of 
the wheel to keep the work 
cool is used. Buffing heads 
or spindles usually consist of 
a standard with a shaft car- 
ried on two bearings, the 
pulley for operating being 
mounted between the two 
bearings in a Y-yoke. This 
shaft usually extends well 
out from the bearings so that 
work may be conveniently 
handled. The ends of the 
shaft are fitted with wheels 
having rims of wood, leather, 
or cloth, which are charged 
with emery or other grinding 
material. With the buffer 

i ^ no rest is used. 

Tool and Cutter Grinding. 
For tools and cutter grinding, 
a better class of grinding 
machinery is required than for the hand-grinding operations. In 
this case the term tool refers to drills, reamers, milling cutters, 
and the finest class of tools, and does not include ordinary hand or 
lathe tools, which usually are ground on a grinder where the wheel 
is in constant touch with water. 

The Cincinnati Milling Machine Company makes a universal 
cutter and reamer grinder, shown in Fig. 61. As the name implies, 
these tools are provided with all necessary attachments for grinding 

Fig. 61. Small Milling Machine Tool and 
Reamer Grinder 
Courtesy of Cincinnati Milling Machine Company, 
Cincinnati, Ohio 


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the cutting edges of all classes of reamers and milling cutters, and 
in many cases may be used for doing a limited amount of cylindrical 
grinding, both internal and external. 

Cutter grinders have become very necessary to the modern 
repair shop through the extensive use of the rotating cutter in machin- 
ing operations and the necessity of keeping these cutters true and 
sharp. In the grinding of cutters, care and judgment must be 
exercised, and not until the operator has become thoroughly familiar 
with all the setting combinations of the machine can he expect to 
get the best results. Since water is not used on the wheels of cutter 
grinders, the wheels are usually quite hard and fine, and light cuts 

Fig. 62. Grinding Milling Cutter with Cup Wheel 
Courtesy of Cincinnati Milling Machine Company, Cincinnati, Ohio 

must be made in order not to draw the temper of the tool at its 
cutting edge. The cutter support should be adjusted to bear against 
the tooth being sharpened, and its position relative to the wheel 
should be such as to give the necessary amount of clearance to the 
cutting edge. A setup of the above grinder for sharpening a milling 
cutter with a cup wheel is shown in Fig. 62. 

Care of Tools. Twist Drills. Much care should be taken in 
the grinding of twist drills to see that the angle and clearance is 
correct and equal on both sides. Correctly ground drills cut faster, 
stand up longer between grindings, and produce the proper size of 
hole. It will be found that a correctly ground drill seldom breaks, 
since it cuts its way cleanly and does not scrape nor jam as it does 
when the angle and the clearance are not right. 


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Proper Wheels. Wheels for any class of grinding should be 
properly adapted to the work as to shape, grade, and hardness. 
Shape and character of the work determine in any case the shape 
of the wheel to be used, while the material of which the work is 
composed, the amount of metal to be removed, and the condition 
of the finished surface must determine the quality of the wheel. 
A free cutting wheel which is run at the proper speed and with a 
light cut is best for accurate grinding, since it removes the metal 
without pressure and consequently cuts the high spots without 
heating up the work. 

However, if the work is to be very accurate, it is best to use 
water on the wheel, as a slight temperature tends to have a noticeable 
effect upon the work. When long cuts are to be taken, it sometimes 
is difficult to get the wheel to stand up so as to give a parallel cut. 
Since the harder wheels hold the emery longer, they can be run 
somewhat slower and they are best adapted for giving cuts of this 
kind. The wheel should have a wide face and be of large diameter 
so as to present as many grains of abrasive as possible to perform 
the required work. It also is necessary to use the coarser feed and 
lighter cuts in order that the wheel may cover the entire surface 
before it drops materially in diameter. 

Manufacturers of grinding wheels give a table of speeds for 
wheels of different diameter, but these speeds are not always best 
suited to the work. All wheels should fit easily, yet closely, on their 
spindle, to prevent any possibility of cracking, and a soft washer 
of uniform thickness should be placed between the sides of the wheel 
and the clamping washer. In grinding long work, it is quite necessary 
to support the work at one or more points between its end bearings, 
for otherwise true work is impossible. 


Function of Drill Press. The standard drilling machine, in its 
various forms, consists primarily of a revolving spindle which carries 
the cutting tool; a work-holding plate, or table; and a substantial 
frame connecting the two. Details of spindle adjustment and also of 
spindle drives and feeds, while they differ in points of detail in the 
several designs and classes, all bear close mechanical relations to 


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each other. Boring holes of comparatively small diameter is the 
specific field for this class of tools, but reaming and tapping these 
holes are in many cases added to the work of the drill by means of 
special tools and fixtures, thus taking over the; work that at one 
time was done on the lathe. 

Method of Action. In the class of drill presses termed standard 
upright, the feed is automatic, and usually a variety of feed speeds 
is given as well as an automatic knock-off that stops the work at 
any desired point. In addition to the automatic feed, both wheel 
and lever feeds are usually provided. The rack and pinion method 
of moving the spindle is common to practically all makes and types 
of drill presses. The spindle usually has its lower bearing in a quill 
which is given a close sliding fit in the head. The feed rack is secured 
to the quill. This has particular reference to that type of drill press 
having a sliding head, the head having a vertical adjustment on the 
front face of the column to adapt the machine to work of different 
heights and to drills and tools of varying lengths. The head is 
counter-weighted so as to make operation convenient. The head 
can be fiwnly clamped in any position. 

An arm supports the work table and this arm is manipulated 
by means of a screw and a crank. It can be swung to a considerable 
angle either side of the spindle and firmly clamped in almost any 
position. In case the work is too high to be supported on the adjust- 
able table, a lower-base table may be used. 

A stationary head usually is found on the smaller machines of 
this class, all the vertical adjustment being accomplished by moving 
the table up or down, as required. Such machines are regularly 
made up to 52-inch capacity, the size indicating the maximum 
diameter of the work whose center can be reached by the spindle, 

In work where small drills can be used, a light machine called 
a sensitive drill should be used in order to obtain the high speed 
required and the lightness of parts necessary. Here, the term sensitive 
commonly means lightness of parts, smooth running, and perfect 
balance, which enables the operator to judge as to the pressure he k 
applying to the drill and, consequently, lessens the danger of breaking 
the drill. Some manufacturers go a little farther and employ at 
some point in the drive an adjustable friction clutch with which the 
speed of the drill can be regulated. 


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Securing Work. Securing work on the table of drilling machines 
requires clamps, bolts, jacks, and blocking, as in other types of heavy 
machines. The same care should also be exercised in the setting, 
for true work requires careful setting. The use of a square and surface 
gage as well as good parallel bars is essential in setting up work for 
drilling. For through drilling, the work must be located so that the 
drill in passing through will enter a slot or the central hole on the 
table. If the work is too large or if for any other reason this cannot 
be done, then the parallel bars on the table should be used before 
putting on the work. These should be sufficiently thick to allow the 
drill to pass through without striking the table. 

Lubrication in Drilling. Drilling of steel and wTought iron 
requires lubrication for the cutting tool, while cast iron and brass are 
drilled dry. Lard oil makes the most satisfactory lubricant, however, 
its cost usually makes its use prohibitive. The lubricant tends to 
conduct away the heat generated by the cutting tool and it should be 
applied directly on the part of the work that is being cut. Some drills 
have a special reservoir in the head for carrying oil and the lubricant 
is forced on to the cutting edge. 


Method of Action. Very general use is made of power-driven 
hack saws in the automobile repair shop. These machines use the 
regular pattern of hack-saw blades, which with proper care do a 
remarkable amount of cutting; the machines require but little atten- 
tion and when properly adjusted will saw off work reasonably square. 
There is usually an arrangement by which the machine comes to a 
stop when the work has been cut and the saw drops through. 

Pressure on the Blades. When the saw blade is new, the weight 
on the top of the saw frame should be a little less than after the teeth 
have become worn, for, when new, the saw bites into the metal con- 
siderably faster than after they have become dulled from use. Fur- 
thermore, there is danger of stripping the teeth or breaking the blade, 
especially if the work is of small diameter. A comparatively light pres- 
sure permits contact with but a few of the teeth at each point in the 
stroke. Tubing is very hard on blades and should be cut with a very 
light pressure and with saws which are somewhat worn. Never use 
oil on the hack-saw blade. 


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Pressure for Different Metals. It also should be borne in mind 
that different metals require different amounts of pressure on the saw. 
Unless one desires to break saws and strip teeth, a close adherence to 
the following must be observed : Aluminum or any other soft metal 
of this character cuts twice as easily as cast iron and approximately 
four times as easily and as fast as steel, consequently the weight on 
the frame of the s&w must be moved forward or backward to give the 
proper pressure. Perhaps the best point for locating the weight in 
cutting aluminum is at the extreme outer end of the frame, about the 
middle for cast iron, and well toward the inner end for steel. Of 
course, there is no regulation of the backward and forward speed of 
the hack saw, hence it is necessary to bring judicious use of the weight 
into play if the life of the saw blade is to be preserved. 

Power hack-saw blades should last as long in comparison to the 
amount of sawing done as the hand hack saw, perhaps longer, if the 
saw is not called upon to do duty at a faster pace than that for which it 
was designed. 

Allowance for Cut. The novice in using the hack saw frequently 
does not make allowance for the cut but measures off the length of his 
piece, marking the exact length, and then starts sawing with the 
blade exactly on the mark. When the piece has been cut off, he finds 
that it falls short of his measurement, perhaps -fa inch. This shows 
that allowance must be made for the width of the saw cut instead 
of sawing directly on the mark, for the -fa inch which the blade 
removes sometimes makes the piece useless. 


Characteristics. Of course the most important power machine 
in a motor-car repair shop is the lathe. In this discussion, the 
engine lathe only will be considered in its simple form, or modifications 
of it, as shown in Fig. 63. The lathe is capable of handling a great 
variety of work. There are four main parts in the ordinary engine 
lathe: bed A, headstock B, tailstock S, and carriage A\ The bed 
is the bench, or foundation, upon which the rest of the machine is 
supported. Placed on top of the bed are what are known as shears, 
which are really tracks upon which the moving parts ride. There are 
two pairs of these shears, and the headstock and tailstock rest upon 
the inside pair and the carriage on the outer pair. The headstock con- 


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tains the pulleys and other devices which receive and transmit the 
power to the work. The tailstock is the holding device for centering 





© 5 
a fe 





material to be worked upon between itself and the headstock. The 
carriage carries the tools which perform work upon the material 
at hand. 


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Before attempting to operate a lathe, it is advisable for one to 
acquaint himself with the mechanism. An examination without 
instructions will show one what levers move the tail stock, adjust the 
tools, regulate the speeds, etc. 

Lathe Tools. It is with the tools for the lathe that the amateur 
repair man finds his greatest difficulties. Only the most important 
points in tool use can be touched upon because of the limited scope 
of this article. Many shapes and sizes in cutting tools may be fitted 
for various jobs which one encounters but the standard tools will 
be found satisfactory for most jobs. Tool-holders for holding 
tungsten steel cutters are 
very useful and are prob- 
ably more convenient 
than the usual lathe tools 
because the cutters do 
not have to be sharpened 
so often. In Fig. 64 are 
shown three typical 
forms of cutting tools. 
The first is a holder with 
straight body; the sec- 
ond, a cutting-off tool; 
and the third, a right- 
hand holder (left-hand 

holders are also avail- Kg. 64. Typical Lathe Tools 

able). There are a num- Curtesy of Armstrong Brothers Tool Company, Chicago 

ber of other necessary tools, of which thread-cutting tools and 
knurling tools might be mentioned. 

Lathe Equipment. Headstock and Spindle. The headstock 
is fastened on the left hand of the bed and carries the main running 
gear of the lathe. At each end of the headstock there is a bearing for 
the spindle. The right end of the spindle is threaded to carry the face 
plate F, Fig. 63, and is recessed to receive the live center G. The dead 
center H is mounted in the tailstock. The work is mounted between 
these centers, the left end of the work being held by a dog which is 
fastened to the face plate to keep the work from slipping. 

Holding Devices. For lathe work in which only one end can be 
supported, there are four classes of holding devices: the center rest, 


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the carriage, faceplate, and chuck. In center-rest work, the center 
re9t of the lathe carries one end of the work and the live spindle the 
other. In carriage work, the work is secured stationary to the car- 
riage and a rotary cutter mounted on the spindle performs the 
machining. With chucks or faceplates, the work is supported in jaws 
within a live spindle. A live spindle is one which rotates and is direct 
driven from the power medium. 

Fig. 65. Combination Chuck 

Every lathe should have one or two chucks as a part of its equip- 
ment. These are made in two-, three-, and four-jaw types, but the 
three-jaw type, Fig. 65, is adaptable for most work. 

Simple Lathe Work. The beginner's job on a lathe is to turn a 
plain spindle between centers. For example, assume that a bar of 
1-inch round steel is to be reduced to a diameter of J inch. 

Centering Stock. The piece to be turned down is first cut to the 
proper length allowing enough for squaring and is then centered. 


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Centering means placing V-shaped depressions in the exact center of 
each end of the piece. 

There are some very handy centering tools on the market which 
are adjustable for different lengths and diameters of stock and afford 
a quick means of placing an accurate center in each end of a bar. 
Fairly accurate centering can be done with a center punch and ham- 
mer. Each end of the piece must be bisected with two horizontal 
lines to obtain the center, this being done with a surface gage. Then 
depressions can be hammered into the ends of the stock by placing 
the point of the center punch at the point where the bisecting lines 
cross, which should be the center point of the stock. Another method 
is to mark the centers, as described, and drill centers into the end in 
the drill press. 

These centers do not have to be deep or wide, but should have 
just enough of V to afford a firm support for the points of the centers. 
Where the work is going to consume considerable time and the piece 
which is being worked is heavy, it is advisable to make deeper centers 
and cut oil grooves into the sides of them with a cape chisel so that the 
center may be frequently oiled. In centering the piece, it must be 
neither a tight nor a loose fit. 

Squaring Off Work. With the work centered, the ends of the 
piece are squared off with a cutting tool. This is an operation 
requiring care. The expert lathe man will square the end to within 
a very small fraction of an inch of the tailstock center, but will not 
ruin the center by cutting into it. 

Roughing Cut. The next operation iS the cutting down of the 
surface of the stock to within about ^ inch of the finished diameter. 
The depth of each cut, of course, depends on the material which is 
being worked on. In soft metals, such as brass and aluminum, a 
fairly deep cut is possible, while in steel it should be around -fa inch. 
This is a matter which can be determined by watching the action of 
the tool and examining the point frequently to see what effect the cuts 
are having on it. This roughing operation tends to work the center 
into a smooth easy-running bearing. 

Reversing Work. The work is then removed from the centers 
and changed end for end. Another roughing cut is made and then 
the work is ready for the finish cut. It must be remembered that no 
part of the work shall receive its finish cut until the parts have been 


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roughed over and the centers have been well worn in. These pro- 
visions are necessary for accuracy. 

Finish Cut. The finish cuts must necessarily be light ones. On 
the second roughing, that is, the cut which is made after the piece has 
been reversed, the stock should be cut down enough, so that only one 
cut is necessary for the finish job. 

Mild steel can be cut with cutting-speed settings of 25 to 100 
feet per minute, depending on the hardness and quality of the stock. 
Although too much speed is to be avoided, it is a fact that the begin- 
ner generally puts far too light, not realizing the possibilities in the 
cutting tool. 

If the surface is to be a polished one, the mechanic must make 
some allowance for filing and finishing with emery. Here is found 
another beginner's fault in that he generally leaves far too much stock 
to be filed off. It must be remembered that it is a difficult proposition 
to file a rotating piece and still keep it cylindrically true. The finish- 
ing cut, when filing is to be done, should leave about .003 inch to be 
filed and smoothed off. This work of cutting down a bar between 
centers is the elemental training for all between-center work, in fact 
to a greater or less degree, for all kinds of lathe cutting. 

Boring. The majority of work done in chucks and with carriage 
support comes under the head of boring. As work of this kind is 
usually performed on solid stock, it is necessary to drill a hole 
sufficiently large to allow the boring tool to enter. This hole can be 
easily drilled in the lathe by using an ordinary twist drill supported in 
the tail center. If the work is to be of large size, the taper shank drill 
is best suited for this work, inasmuch as it readily cleans itself of the 
cuttings. If the drilling is to be very deep, the drill must be fre- 
quently drawn out, cleaned, and oiled, or the generated heat will 
damage the flutes of the drill. 

Drill and Boring Tool. The size of drill which one must use for 
making holes preparatory to boring depends, of course, on the nature 
of the work. If the work is to be small in diameter and of consider- 
able depth, a drill within one-sixteenth of an inch of the diameter of 
the finished hole should be used if possible. If the hole is to be of 
large diameter and shallow, the drill should open a hole large enough 
to permit the entry of a short stiff boring tool, and this naturally does 
not have to be very large. There may be obtained boring bars of 


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universal type which will take a variety of tool shapes. In these the 
tool is secured in a mortise through the bar by suitable wedges or, 
more usually, the tool is of round steel fitted into a hole through the 
bar and secured in position by a set screw. In cylinder boring, or 
reboring, more than one cutter is generally used inasmuch as a single 
cutter would be liable to spring the cylinder and gouge the metal. 
The use of a cutting bore equipped with three cutters gives a tool 
which will operate steadily and make a very satisfactory bore. As in 
all cases in lathe work, the finish cuts should always be light ones to 
insure true work. 

Mounting the Work. It is more or less of an art to fit a piece, 
especially an irregular one, into a lathe chuck. No rules can be laid 
down for this inasmuch as each piece must be centered to take care of 
its regularity or irregularity in shape. In a good many jobs, the work 
is of such shape that it cannot be held in a chuck. In such cases, the 
work may be clamped to the face plate or to an angle plate fastened 
on to the face plate. This is a setup which requires a great deal 
of care and patience. In such parts as gear blanks and other pieces 
having hubs, the work should be chucked on these hubs whenever 
possible. Work held in this manner will run true if properly bored 
and turned. It must be remembered that a chuck centers the job. 
For instance, if one has a piece with a flange and a hub as a part of it, 
he can have the bore run true with the hub by chucking the work on 
the hub; but if he desires to have the bore run true with the flange, 
he should chuck the work on the flange. 

Degrees of Fit between Shaft and Hole. When a piece of shaft- 
ing or tubing is to be turned down to fit a certain drilled or bored hole, 
there are three kinds of fits which apply, viz, working fits; 
driving, or forced, fits; and shrink fits. A working fit is one such as is 
found in a bearing, that is, the work will be so machined that it will 
slide easily in the piece. A driving, forced, or press, fit is one in which 
the work is so machined as to require pressure, either by hammering 
or in an arbor press, in order to get the cylindrical stock into the hole. 
In automobile construction, a working fit is generally machined so 
accurately that the difference in diameter between the cylindrical 
piece and the hole is extremely small, and still a perfect sliding fit is 
maintained. The importance in fitting bearings is to have the 
surfaces of both pieces true to one another within .001 or .002 inch. 

189 Digitized by GOOgk 


In accurate work, this agreement runs into ten-thousandths inch. 
A shrink fit differs very little from a driving fit. It must be 
so machined in both pieces that, when the bored or drilled piece is 
heated enough to expand it a few thousandths of an inch, it will allow 
the cylindrical piece to be easily pushed into it. Then when the 
heated piece shrinks or contracts, a very tight fit is naturally the 
result. There is one thing to be avoided in making a forced fit and 
that is the tendency to swage the metal. This is not the case in a 
shrink fit inasmuch as the piece goes in easily and then the hole closes 
squarely down upon the center. It is very important in making a 
press fit that the cylindrical piece be introduced squarely into the 
hole. In the shrink fit, it is quite necessary that the relative posi- 
tions of the two parts, one within another, be quickly made because 
the shrinking takes place rapidly and causes the two parts to lock 
together. With a forced fit, in which it is contemplated that the 
parts will have to be separated, the surfaces of the hole and the cylin- 
drical piece are lubricated, thus preventing oxidization of the metals 
and making it easier to drive out the shaft. The easiest way to do 
this is to heat the ring, thus expanding it, in the meantime keeping the 
shaft as cool as possible by pouring cold water over it. 


Characteristics. In many respects the shaper and the planer 
are alike. The same cutting tools may be used in either and the 
general principles involved in the operation of these machines are 
quite similar. However, they differ materially in design; with the 
planer the work moves to the tool, while with the shaper the tool 
moves over the work. On the planer the vertical and lateral feeds 
are given to the tool, while on the shaper the lateral feeds are usually 
given to the work and the vertical feed to the tool. In what is known 
as the traverse-head shaper, both feeds are given to the tool §nd the 
work is held perfectly stationary. A shaper of stdhdard design is 
shown in Fig. 66. 

Clamping Work in Shaper. Proper securing of the work in the 
vise on the shaper table for planing operations is a most important 
step in the production of satisfactory work. The variety of work 
assigned to the shaper is great and the operator will continually find 
himself with new problems to solve, problems that require the exer- 


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cising of good judgment and care. In the majority of cases more Skill 
is required in setting up the work than in the actual machining. 

In work that is compact and heavy and where the amount of 
metal to be removed is comparatively small, there is but little danger 
of springing the work; but if the work is large, of irregular shape, or 
light, the danger of springing is materially increased. In the first 



Fig. 66. Typical Pillar Shaper 

place, lack of uniformity in clamping distorts the work and throws the 
machined surfaces out when it is undamped. Again, the removal of 
the outer surfaces of a casting or forging, which frequently relieves 
shrinkage and forging strains, throws the work out of true. The first 
of these difficulties can be overcome only by using the utmost care in 
setting up the work, and the second, by first roughing off all surfaces 
as far as possible before taking any finishing cuts, thus allowing the 
work, after the roughing, to assume its normal condition. 


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It is very important that the clamping of the work to the table 
be done with due consideration for locating the points of clamp 
pressure directly over the points of support. The supports should be 
firm and bear about equally on the work and the table. If only a thin 
shim is required to level up the work, this should be of metal in pref- 
erence to card board, leather, or any compressible material which will 
allow the clamp to spring the work. Good blocks and parallel bars 
are indispensable in the shaper and planer outfits. For work where 
the points cf support vary in height, leveling wedges and small jack 
screws are excellent, as they can be adjusted quickly to any desired 
height. These wedges, especially if any single wedge is used, should 
have only a very slight taper. 

Operation Suggestions. When it comes to operating the shaper, 
the beginner should keep a few points closely in mind. Not all 
geared shapers have a fixed length of stroke, the depth of the cut and 
the speed of the countershaft affecting in a certain degree the points at 
which reversal takes place. Some allowance must, therefore, be made 
for the overtravel of the tool. An excessive amount of overtravel, 
however, means a large loss of time. Roughing cuts should be as 
heavy and with as coarse feeds as the machine will conveniently 
handle and as the strength and character of the work will permit. 
First, before planing side surfaces, see that the top of the tool box is 
inclined from the work. This allows the tool to swing out and clear 
the work surface on the return stroke. If it is not inclined, the point 
of the tool drags hard on the work surface and, should it be inclined to 
the wrong side, the tool will swing into the work and do damage. 
Raising the tool clear of the work on the return stroke preserves the 
cutting edge. Means are often arranged for accomplishing this 

Keep the cross-rail clamped firmly to the housing, when in use, and 
parallel with the table. Before putting in the feed, see that the feed 
gear is on the right spindle, as otherwise the tool may start up or down 
when it is intended to move across the work. As there is usually 
more than one way to do a certain piece of work, you should study 
which is the best way to do it. Those factors that have a great deal 
to do with turning out quality and quantity work are the manner in 
which the work is set up, the kind of tools and the way they are ground, 
as well as the efficient handling of the machine. 


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Milling Machines. Although the milling machine is not an 
essential part of the well equipped repair shop, it is really a necessity 
in a large shop which does building and rebuilding and all kinds of 
machine work. In its elemental form the milling machine is made up 
of a rotating cutter which is held in one plane and a moving bed which 
carries the work under the cutting edges of this cutter. If one is to 
thoroughly familiarize himself with one of these machines, there is so 
much to learn in the setting and manipulation that it is hardly prac- 
tical to try to give a detailed list of instruction herein. Therefore, 
only a brief description of the machine will be given. If a man has no 
idea of the operating principles of a milling machine, the quickest and 
best way to familiarize himself is to appeal for instruction from a man 
who knows how to operate this machine. The milling machine is a 
much more accurate tool than a shaper inasmuch as it cuts stock off 
with one sweep where a planer requires several sweeps with new 
adjustments for each sweep if accurate work is to be done. 

Types. The plain and universal milling machine of the column 
pattern are the ones generally used for repair-shop work. In this 
machine, the upper portion of the column carries the spindle and cone, 
this spindle being back-geared in the same manner as is a lathe. The 
outer end of the spindle is supported by a suitable overhanging arm. 
The work table is adjustable vertically and horizontally, these adjust- 
ments being made by means of screws which operate with wheels and 
handles. There is a wide range of cutting speeds provided in the 
feed mechanism. 

Cutters. Milling machine cutters are produced in a variety of 
forms designed to take care of different kinds of work. One of the 
most commonly used cutters is the axial type which has teeth on the 
cylindrical surface only. In the small cutters, these teeth are straight 
across the surface, and in cutters above 1§ inch they are cut spirally. 
Another and similar type of cutter is the plain milling cutter with 
nicked teeth. This has merit in being able to take a deeper cut 
inasmuch as the chips are broken up by the nicked cutting teeth. 

The narrow cutters come in what are known as straddle-mill, 
radial-face, and side cutters. Another type is the end, or shank, 
milling cutter which is similar to the radial-mill except that it has its 
independent shank. These are generally used for small milling work, 


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and frequently the teeth are cut spirally. When one desires to do slot 
milling at the end of a shank cutter, there is a special type provided, 
having radial teeth on the inner ends provided with cutting edges, 
which enables them to cut their way out when moved along the 
work. For cutting standard T-slots, there are special tools provided 
having a shank end and inasmuch as they work with the shank 
vertical to the slot, it is necessary that the center portion be cut away 
first to allow the parrow end of the shank to pass between. For 
annular cutting, there is a variety of tools built up to take care of 
every kind of this work. Probably the most economical for milling 
tools are those having removal cutters which may be replaced when 
worn out. 

Planers. It is only in the very large repair shops that the planer 
will find use. As the name indicates, the planer is used for finishing 
flat surfaces. As has already been said, the planer resembles the 
shaper, and no further description will be given. 


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Service of Public Garage. During the years of development 
of the automobile, the problems of its care have been solved with 
equal precision. The automobile mechanic has become skilled in 
his line, so that the repair shops, which are almost invariably a 
part of a public garage, render valuable service in curing the aches 
and pains which every car develops at some time or another. The 
system of garage service, too, has become standardized; but a point 
that is appreciated all too little in the business is that a garage is 
essentially a service proposition. A man takes his car to the garage 
to be cared for and pays the charges for this to relieve himself of 
this work. Many men patronize a public garage because they do 
not want the work of washing, cleaning, and oiling their cars; many 
others go there because they lack mechanical knowledge and prefer 
to pay for this knowledge and the service which goes with it, in the 
way of adjustments, replacements, and general care, rather than to 
try to learn these things themselves. 

Viewed from this standpoint, the garage is nothing but a service 
proposition, rendering service which the public would rather pay for 
than to carry out itself. No man should go into the garage business 
with any other thought than to render the utmost of service and to 
charge a fair price for it. Many garages have been unsuccessful 
in the past because their owners lacked an understanding of this 
principle, the businesses having been run with the idea of rendering 
as little service as possible and getting as much money as possible 
for it; in short, the garage business has been reduced to a housing 
proposition, that is, payment for floor space and a roof to protect 
the cars from the weather. Another phase of this question is that 
many garages have been unsuccessful in the past simply because 
they rendered services of value without making an adequate charge 


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for it. The garage can no more afford to give away its product — 
services and work — than can the butcher or baker afford to give 
away his produce. Similarly, when the garage takes on the sale 
of the most needed accessories as a side line, it cannot afford to give 
these away even in the smallest quantities. Therefore, no one should 
go into the garage business unless thoroughly imbued with the idea 
of selling service and getting as well paid for the service rendered 
as is legitimate. Moreover, this thought should be prominent from 
the start, so that the building can be planned and built with facilities 
for rendering this service the most quickly and easily, and with the 
least cost to the management. 

Selling Cars as a Side Line. The question of whether it is 
advisable and profitable to sell cars as a side line and whether it 
works in well with the garage business is one that depends upon the 
place where the garage is located and also upon the man. There 
undoubtedly are situations in the country or in the small town 
where this combination is a nautral and desirable one, because the 
business will be small enough to make it almost necessary to concen- 
trate everything — sale of cars and of accessories, and the care and 
repair of both after the sale — in a single building and tinder one 
management. As a rule, however, it has been found that the two 
lines are separate businesses and require separate and distinct 
methods of handling. The men fitted for one business are seldom, 
if ever, suited to the other, and the nature of the buildings — its 
fittings or surroundings, equipment, care, heating, lighting, and 
many other things- is so different as to warrant separating the two; 
in short, it is very seldom that the garage and the salesroom can be 
operated together to advantage. 

Selling Accessories. The secondary question of whether it is 
advisable to go into the sale of accessories must also be considered. 
It might almost be taken for granted that the garage would sell oil, 
grease, and other lubricants; gasoline, kerosene, and other oil prod- 
ucts; but in the matter of the smaller but frequently used accessories, 
such as spark plugs, tire-repair kits, jacks, and other small tools* 
tires, and similar supplies which are in constant demand, local 
conditions outside of the garage usually govern. 

In the country or in the small town, where automobile accessories 
and supplies are not handled by any other stores, it is advisable for 


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the garage builder to consider this point and to provide space and a 
suitable arrangement for handling them. 

In the city, on the other hand, there are many stores that handle 
accessories on a scale far beyond the ability of the garage man. 
This enables the big stores to give a choice in the way of quality and 
price that puts the garage man at a disadvantage. To sum up the 
matter, where the number of people, and, as a result, the number of 
cars and trucks, within a reasonable radius of the garage is great, 
there will be stores specializing in supplies and equipment; and it is 
inadvisable for the garage man to go into their sale on as large a 
scale as capital and business in sight will permit. 

Special Side Lines. Practically the same conclusions apply to 
the matter of including the auxiliary business. By side lines, reference 
is had to vulcanizing and tire repairs; to painting, upholstering, and top 
work; to general machine shop work and alterations on a large scale, 
such as the remodeling of old cars, the conversion of cars into trucks, 
etc.; complete overhauling which necessitates facilities and equipment 
beyond the average garage; and other things. In the country and 
the small town, it is advisable to go into these various auxiliaries as 
far as the business in sight will warrant, but in the cities where there 
are specialists in these lines who can give more and better service, 
give it quickly and advantageously, and perhaps at a lower price 
with profit, it is inadvisable, and the garage man should not attempt 
anything outside of strictly garage service. 

In the medium size town, it is frequently advisable to consider 
the general proposition of having a number of such auxiliary busi- 
nesses in the same building, apparently component parts of the 
garage, but, in reality, separate and distinct firms, each run by a 
different man. This makes a convenient working unit for the people 
owning cars, yet the various businesses being separate, and each 
run to facilitate a special line of work or endeavor, they do not 
conflict; on the contrary, each one derives business from its close 
association with the others. 

Financial Problems. One point which should be considered 
with more care than any other is the matter of financing. It is a 
big mistake to start a garage on the assumption that it will pay a 
profit from the start. This is seldom the case, and the prospective 
garage man should plan his finances so that he will have sufficient 


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money to care for running expenses for a considerable length of 
time. This should be done even if the initial building is not built as 
large as the garage man plans to have it ultimately, and even if the 
equipment is not as complete as might seem desirable. In a very 
short time, if the garage has been planned wisely, the location chosen 
carefully, and if the business is run on a basis which holds all boarders 
who come in and attracts more, the profits will come, and the exten- 
sions of building and equipment can follow. 


Probably no single item will have a greater influence on the 
success or failure of the garage business than the wise choice of 
location. Three things must be considered: existing car owners, 
the location and proximity to main highways, and the allowable 
size and shape of the building. The value of the land wHl have an 
influence on the overhead expense, for what might seem an ideal 
location in every other way may be beyond the financial means of 
the garage man. 

Land Values and Size of Building. Size is closely inter-related 
to value of land and to the cost of the building, as will be shown 
by a simple example. If a plot 80 x 100 can be arranged to such 
advantage as to hold the same number of cars as another plot 100 x 
100, and the former cost but $8000, while the latter is held at $10,000, 
other things being equal, the first is the best business proposition. 
Suppose both plots will hold 56 cars; then the land cost alone is 
$143 per car for the first lot and $178 per car for the second. Obvi- 
ously, a greater price would have to be charged for storage in the 
second case than in the first, to make an equal margin of profit. 
And what is true of the land is equally true of the building, for 
a building 100 x 100 would cost at least 15 per cent more than a 
similar one which measured only 80 x 100. 

Central Location in Territory Desirable. In choosing a site 
there are two points to consider. Generally speaking, that site in 
the proposed territory would be best which is in the geographical 
center of the cars that would use it. This could be arrived at mathe- 
matically, of course, but this is unnecessary, because a rough 
inventory of the cars upon which the garage would depend for patron- 
age will locate a general center of action that is satisfactory. 


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If the surrounding residents protested against a garage at the 
location decided upon, or if there were any other reasons why it 
could not be located in the place desired, a second item would have 
its influence upon the second best choice. This is the proximity 
to a through highway. The importance of this point may be judged 
from the plain statement that many garages, during the touring 
season, derive more than 25 per cent of their receipts from passing 
cars. The transient trade grows more important each year as touring 
increases. The influence of this growth would be such that when 
the second choice has to be made outside of the center of action of 
the territory to be served, this location should be such as to bring 
the garage nearer, as much nearer as practicable to the point where 
it can retain the permanent trade and still get that of the through 


Methods of Calculating Size. The inventory of the proposed 
territory is valuable, since it gives a good basis for the size of the 
garage. Obviously, in a territory with but 25 cars all told, of which 
perhaps 15 were well housed in private garages, it would be foolish to 
build for more than 30 to 40 cars, that is, the 10 to start with, perhaps 
as many added in the first year because of the presence of the garage, 
and an average of 4 or 5 transients would be about all that could 
be counted on throughout the first year. This totals less than 25 
cars on the average, and a building large enough to house 30 to 35 
cars is all that this much business would warrant. Of course, a small 
quantity of oils, gas, and minor supplies would be sold to the owners 
of the other cars, but the profit from these would be very small 
because the sum total of the sales would be small. Transient trade 
bulks up large, by comparison with steady boarders, principally 
because it is almost universally charged about twice as much, that 
is, a garage having a flat monthly rate of $15 a month, will charge 
all transients $1 a day, or $30 a month, making one transient, while 
it stays, the equal of two steady boarders. The boarders, however, 
form the backbone of the business, since without them the garage 
could not exist to take the transient trade. 

Knowing the number of cars available and estimating the addi- 
tions and the average number of transients during the first year, 


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a rough total can be arrived at which can be used to determine the 
size of the building. An average car must have a floor space of 
approximately 15x7, and at least 20 feet should be allowed for a 
comfortable aisle, or driveway, between standing cars. Few cars, if 
any, actually total 15 feet in length, or 7 feet in width, but, on the 
other hand, cars cannot be placed in the space assigned within a few 
inches; so the space given is about as small as can be used. 

Methods of Arranging Cars. The size of car and of the aisle 
space brings out our first rule of garage proportioning, in which 
there are three ways of arranging cars: one row on each side of a 
central aisle; two rows deep on one side, and one row on the other 
side of a central aisle; two rows deep on each side of the aisle; also 
duplications of these arrangements when the garage is unusually 
wide. Taking the figures given above, we get the following preferred 
widths, namely, two 15-foot spaces and a 20-foot aisle for the first 
case, or a 50-foot total; three 15-foot spaces and a 20-foot aisle in 
the second, or a 65-foot total; and four 15-foot spaces and a 20-foot 
aisle in the third, or an 80-foot total. Doubling up on these gives 
100 feet for the first, 130 feet for the second, and 160 feet for the 
third. This last is probably too wide for all normal conditions, 
but the other five are possibilities. 

To make these more clear, Fig. 1, in which these five cases are 
shown, respectively, at A, B, C, D, and £, is presented. The depth 
needed per car is 7 feet; so the width having been determined, and 
one of the above five methods having been fixed upon as the best 
for the purpose, the total depth is found by dividing the number 
of cars to be housed by the number accommodated in one 7-foot 
width, and then multiplying this result by 7. Thus, suppose a 
narrow garage has been fixed upon, under scheme B, Fig. 1, which 
accommodates three cars in one width, or 7 feet. And suppose the 
total number of cars to be provided for is 90; then 3 goes into 90 30 
times, and 30 times 7 gives 210 feet for the total depth. As this is 
deeper than lots usually run, it would be best to change to scheme 
C, which accommodates 4 cars per strip of width, thus 4 goes into 
90 22 plus, and 22 times 7 equals 154 feet for the depth. Under 
certain conditions, a strip might be available straight through the 
block, so that instead of changing to scheme C we could go the other 
way, changing to A and making the garage narrower and longer. 


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On this basis, 90 cars would need a strip 50 x 315 feet. The advantage of 
the last method would be to provide two entrances, one on each street. 

. — V 

* * 

t W- 




% • 










* -: 








The writer has seen cars placed in a garage parallel to the aisle, 
as sketched in Fig. 2. This placing has the disadvantage of making 


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much extra work in putting in or taking out a car behind those in 
the front row. Usually, where the cars all face in one general north 
and south or east and west direction, there is little trouble in 
getting a car in or out, except at the times when all owners come in 
or go out at once. But as soon as a different placing is introduced, 
there is difficulty, for not only must more cars be moved, but they 
must be moved in different directions, and some of those moved 
will obstruct the passage of the car coming in or going out, thus 
making double work. This method, however, is usable; in fact, 
it is in fairly wide use. It increases the width in scheme A to about 
57 or, in round figures, 60 feet, and adds one car in each two strips 
for every 14 feet. In B it makes the width 72 or, in round figures, 75 



— — «, 



"■ 15 *i 








" ■ y ■- 









Fig. 2. 

Modifications of the Garage Arrangement* offFig. 1, Made Possible by 
Turning Part of the Cars 

feet, and adds one car for every 14 feet of depth. In C it makes the 
width 87 or, in round figures, 90 feet, and adds one car for each 14 
feet, or adds two — one on each side — when it is 95 feet in width. 
Schemes D and E may be handled in a like manner. 

Modifications of Size Due to Situation. If the garage is situated 
in a small town or in the country, it is possible to slightly trim the 
dimensions given. Thus, a Ford car needs but 12 feet; being uni- 
formly narrower and turning shorter than other cars, it can be handled 
in a narrower aisle. This would mean that a garage entirely for 
Fords could have/ under scheme A, Fig. 1, a width as little as 12 + 15 
+ 12, or 39 or, in round figures, 40 feet. This is an unusual supposition, 


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but is given to show how valuable the inventory of the territory is 
and how complete it should be, for this inventory would show the 
relative number of small machines. 

Other Modifications and Deductions. Space for Office Fuels, 
Etc. In what has been said previously, the entire inside of the build- 
ing has been figured as storage space and aisles for cars. This is 
not ordinarily possible, for there are many other things to consider, 
all of which deduct from the interior space. First, there is the 
office which must be well and wisely located, for it must govern the 
incoming and outgoing in such a way as to keep a perfect check on 
all cars. Then there is the room, preferably separate from the office, 
for the oils, fuels, and greases. Usually, the building regulations 
require a fire wall all around this room, and, even if they did not, it 
is good policy to build it that way. Then, the wash rack is a very 
important place and takes up the space of at least two cars, possibly 
more. Toilet rooms for both sexes, lockers, air compressor, and other 
things require floor space. Also, if there is a sales department 
connected with the garage, either for small things or for the larger 
units, as tires, a show room and storage space are both needed. 
Then, too, there is the matter of auxiliaries. If the shop has a tire- 
repair department, space must be allowed for this. Similarly, if any 
of the other auxiliaries are included, they deduct from the floor space 
for car storage. 

Space for Stairways and Elevators. If the building is more 
than one story high, the space taken up by the elevator and imme- 
diately surrounding it on all floors, or that taken up by ramps, or 
inclines, if they are usfcd, must be considered. This space might be 
thought to be small at first, but, in figuring it over, it will be found 
that the elevator must be at least 16x8 in size, which means at 
least an 18 x 10 total. To this space must be added at least 10 x 10 
for the machinery to operate it, and approximately as much more, 
10 x 10, which must be kept clear at the elevator in order to give 
access to it readily. This space totals 38 x 10, a space almost equal 
to four cars, which should be deducted on each floor, while ramps 
would take out still more space. 

Space for Posts. In order to support the roof or upper floors, 
as the case may be, posts or expensive structural steel trusses are 
necessary. The location of these posts influences the arrangement of 

205 - Digitized by 



the cars, both as to width and as to depth, so that unless they are 
very cleverly placed much space can be lost around them. In a 
comparatively large garage of considerable width where more than 
one row of posts is needed, the space taken up by posts mounts 
up considerably, and can easily total that of two or three cars. 

Summary of Deductions. By the time the space of two cars is 
allowed for the office, that of two more for toilets, one for lockers, 
one for the fuel and oil room, that of two or three more for the wash 
rack or twice this amount if there are two wash racks, that of one 
or two for the posts, etc., and the total added up, it is found that a 
fairly large percentage of the storage space is gone. If the building 
be one with upper floors, it is found that elevators or ramps have 
taken out fully as much more, and that all this deduction is repeated 
on each floor, with the exception of the office space and of the fuel 
and the oil spaces. 

All the modifications and deductions stated in the preceding 
paragraph must be taken into account in laying out the original 
plans and in buying the site and erecting the building. If the net 
floor space which can store cars, and the number of cars which can 
be stored in this space be multiplied by the average price which can be 
obtained for each space, the answer will, to a great extent, determine 
the revenue. Consequently, if the deductions reduce the space 
below the point previously considered necessary, the size should 
be increased to compensate for this loss, that is, if deductions cut out 
10 cars that were figured in,' the size should be increased sufficiently 
to house 10 more cars than were provided for originally. 

The plans for four different sizes of garage will be considered 
in detail. These plans are not offered as ideal, for such a thing as an 
ideal garage does not exist, but they will present, in a more easily 
^grasped form, some of the difficulties of garage planning and construc- 
tion. The sizes have been selected upon the basis of being: small; 
medium size; large; very large. 

Except for the very large size, which is too large for any but 
city use, these garages might be located anywhere. After the garages 
have been considered in detail, the matter of equipment will be taken 
up, and the equipment that is generally considered necessary will 
be indicated; also the equipment that is desirable and perhaps 
profitable but not necessary, as well as that which the handy garage 


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man can make for himself; most of the latter equipment is also 
desirable and profitable, but it is not absolutely necessary. Finally, 
such other details as heating, ventilating, safety, lighting, cleanliness, 
and other similar subjects will be considered according to their value. 



While it might be considered small in the country, or in a very 
small city or town, a garage approximately 50 x 100 is generally 
spoken of and considered as a small garage. Such a garage can seldom 
be arranged to regularly care for more than 25 cars and take care 

Fig. 3. Average Arrangement of Small Garage (50 x 100) to House 27 Cars 

of them well. If any accessories are sold, the space they occupy 
cuts down the number of cars. If an agency for a car or a truck 
is maintained, space must be provided for a show room and sales- 
room, and a building of this size can seldom be used to store as many 
as 20 cars. Although it may seem large, it is, in reality, small. 

Typical Arrangements. Layout 1. Let us see how this space 
can be arranged to the best advantage. In Fig. 3 is shown a layout 
in which the cars are arranged along the two walls at the front part 
of a 50 x 100 building, but the last 32 feet of this space have been 
partitioned off into a form of repair shop, with a bench along the 
rear wall and a few tools in one corner. This layout provides no 
office and no locker space, but just the bare storage room, with a 

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little space for repair work, and few facilities for doing it. It accom- 
modates 26 cars, as the sketch shows. 

Layout 2. If the intention was to have storage space only, 
with simply a bench provided for repair work, this space could be 
managed more advantageously by rearranging it, as shown in Fig. 4. 
Here the partition has been taken out, and for a short distance 
along one wall all cars have been moved out into the central aisle 
a few feet. This allows room for the work bench and space beside 
it in which to do work. Space is provided for 28 cars, 2 more than 
in layout 1, and, if it were necessary, two cars could be put against 
the rear wall in the aisle, as shown by the dotted lines, to make a 
total of 30. Of course, the corner for tools and the tools themselves 

Fig. 4. Rearrangement of Small Garage to Hold 28 (and possibly 30) Care 

have been taken out, but, aside from that, the rearrangement has 
added almost 16 per cent to the revenue. 

Layout 3. This is perhaps the maximum space for this size of 
garage, as nothing but storage space has been provided. If a wash 
rack is to be added, that will cut the storage space down. So, too, 
will an office for accessories and a show room. Another arrangement 
is shown in Fig. 5, in which the entire front of the building is given 
up to display, the cars entering at the rear. Note how the show room 
takes the larger part of the front, and the accessory salesroom the 
other part; also how the offices, toilet rooms, and stock room take 
up space back of the salesroom, so that the garage itself houses 
but 19 cars. The wash rack is really in the aisle, although at one end. 


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Layout 4* By eliminating the private office, or rather combining 
it with the other office, with a door opening into both the show room 
and the accessory salesroom, and by leaving out the toilets, as indi- 
cated in Fig. 6, which is this same plan revised, 5 cars may be added to 

the storage total, making 24 in all. This arrangement would be 
particularly good if the shop walls of the central office were of glass, 
for then it would be possible for a person in the office to keep track 
of the entire establishment — show room, accessory salesroom, and 
garage. * This layout provides for oil and gasoline storage, tools, 


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work bench, wash rack, salesroom, accessory room, stock room, 
and office, yet it houses 24 cars. 

Layout 6. Another 50x100 floor plan is shown in Fig. 7. 
This plan provides for the grouping in one unit, on the right side 

of the entrance, of the two salesrooms, office, stock room, and men's 
toilet. It is intended for the man or firm wishing to have consider- 
able window display space at the front, and, for that reason, both 
the salesroom window at the right and the other window at the left 


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are arranged for displays. The window at the right is for cars, 
while the one at the left is for small parts. A good idea of this plan 
is obtained from the front view of the establishment, Fig. 8. This 

Pig. 7. 

Different Arrangement of Small Garage with Show Rooms and Offices 
Courtesy of "Motor World' * 

plan is mentioned because it has a bearing on the floor space available 
for car storage, the display window for accessories and the oil-barrel 
arrangement just back of it taking up the space of one car. 

Fig. 8. 

General Appearance of Front of Garage Shown in Fig. 7 Plan 
Courtesy of " Motor World" 

A modest repair outfit at the rear is composed of a work bench, 
lathe, drill, emery wheel, and press. The capacity, as shown, is for 
17 cars, but by arranging the cars directly back of the accessory and 
parts stock room and parallel to the aisle, as shown in the dotted 
lines, one car can be added, making the total 18. 


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Modification of Layout 5. Considering the diversity of other 
things provided for, this layout seems excellent. For the man who 
might like this arrangement, yet who does not wish to give any 
space to car sales, the layout shown in Fig. 7 can be modified. The 
oil barrels can be removed and the accessory department moved to 
the extreme front, while the accessories and parts stock room can be 
eliminated. If the garage man sold only small accessories — the little 
things which could be handled at a simple counter or from ordinary 
shelves on the wall back of the counter — he would need little or no 
stock room, as such storage room as was needed for excess stock 
could be found under the counter, on the top shelves, or elsewhere. 
By this rearrangement, as can easily be figured, 8 or 9 cars may be 
added, making the total 25 to 26 cars, without changing the front 
or general good arrangement; in short, the layout shown in Fig. 7 
provides for a car-agency arrangement, and also storage for 17 or 
18 cars. The same layout without the agency space can be arranged 
for the storage of 25 or 26 cars. 

In making his initial plans and the building layout, the garage 
man must balance his income from storage plus that from car sales 
against the increased income from storage alone, that is, in the two 
layouts just shown in Fig. 7 and its suggested change, he must figure 
out whether he will make more money from a 17- or 18-car garage 
and a sales agency, or from a 25- or 26-car garage and no sales 
agency. The accessory sales are about the same in the two cases, 
although possibly in the case of having a car agency, he might sell 
more accessories to the people who bought cars from him. This 
question, however, is problematical. 


Typical Arrangements. Layout 6. In the following, a garage 
is considered of medium size, which has a floor space of approxi- 
mately 10,000 to 12,000 square feet. In a square form, this gives 
from 100 x 100 to 100 x 120 feet, and in a long narrow form, 
60 x 200 feet, with various other forms in between these two. As 
a matter of fact, neither the exactly square form nor the unusually 
long and very narrow shape is an advantageous one. A floor plan of 
a Brooklyn, New York, public garage is shown in Fig. 9. This garage 
measures exactly 100 feet each way. It is on a corner, with an 


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entrance on each street. Moreover, the single central post appears 
to give a maximum of floor space. The supply room and the office 
are small, and apparently little space is wasted or taken up for 
things other than car storage. Yet, when we come to figure out 
the number of cars which this building will store — only 30, as can 
be figured from the plan, Fig. 9, and with little or no aisle room, 
so that cars would have to be moved every time one not in the 
first row was taken out — the truth of the statement that the square 
shape is not economical is proved. By inspecting this layout 
for an opportunity to improve upon it, we see that only two things 
can be rearranged to advantage. One is to reduce the number and size 
of the lockers. This size 
and arrangement may 
have been forced by local 
conditions, competition, 
or by some other reason, 
but even that arrange- 
ment of lockers is not 
as good nor as economical 
of space as if they were 
grouped in one corner. 

ever, seems to occupy the 
best corner of the build- 
ing, yet there is a space 
on the Sea Gate Avenue 
front, between the office and the door, which is large enough for the 
washstand but which will hold only one car. By moving the washstand 
to this spot, the other corner would be available for cars. These 
spaces are shown by the dotted lines, which indicate that four cars 
could be put in the space now occupied by the washstand and this 
number, less the one lost in the other corner, would make a net gain 
of 3, bringing the total to 33 cars. If, now, it were possible to place 
the lavatory in a corner of the office space by slightly reducing its 
size, say from 8 x 8 to 6 x 7, two cars could be put in the space which 
it now occupies. So this square shape could store as many as 35 cars. 

It compares unfavorably with the preceding layout, the 
rearranged Fig. 7, which was only 50 x 100 and was rearranged to 

Fig. 9. 

Brooklyn Medium Size (100 x 100) Garage, 
Located on Corner 


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house 24 cars, while this 100 x 100 can hold 
but 35. If this shape were as efficient as the 
other, the doubled size should hold at least 
twice as many cars, or 48. 

Layout 7. A New Jersey establishment, 
very long and narrow in shape, is shown in 
Fig. 10. This garage is built on a corner and 
extends through to a rear street, so that it 
has three street fronts. The third street front 
is utilized only for light, as the location of the 
repair shop at the end precludes having an 
entrance there. The dimensions show that this 
garage is not quite as large as the other, since 
it has but 8100 square feet of floor space. 
Moreover, it is so narrow that a row of cars 
cannot be put along each of the two walls 
to take advantage of the length. The best 
that can be done is 20 cars along the one 
all, with a maximum of 6 along the street wall, 
and even this number can be obtained only 
by placing them at an angle. The repair 
shop is sufficiently large so that it might 
easily hold 5 cars on which work was being 
done. This gives a maximum of 31, or if the 
repair shop be considered as separate from 
the storage, 25 only. 

Two ways of improving layout 7 suggest 
themselves. One of these is to move the 
chauffeur's room, charging panels, and trans- 
former inside the repair shop; by doing this, 
storage space for 2 more cars along the wall 
could be gained. The other method would 
be to move the repair shop up alongside of the 
office and the tire room. This can be done 
in two ways: It can be placed along the back 
wall, where a depth of 49 feet would give it 
about 60 per cent of its present space, replacing 
7 cars. Then at the rear, in its former space, 


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providing the vulcanizers were moved with it, space for a total of 
9 cars could be made. This would be a gain of 2 cars, which, 
with the previous gain of 2 by moving the chauffeur's room, gives a 
total of 30 storage cars. On the other hand, the repair shop would 
be so small that it could accommodate but three cars for repairs. 

The way to improve this layout would be to place the office 
and tire room back alongside the repair room, allowing the repair 
room to occupy the full width of the building. In this rearrangement, 
the chauffeur's room, charging panels, and transformers would be 
taken care of also, so that while 16 feet would be taken off the length, 
the entire balance of the floor space would be available for storage 
of cars. This rearrangement would not take off anything at the rear, 
and the space added at the front corner would store 6 cars, while 
one more could be set at an angle against the outside wall. This plan, 
then, would bring the total capacity of this long narrow garage up 
to 33 cars. The only way in which the layout could be further 
improved would be by the removal of one of the doors on Railroad 
Avenue; by doing this, 2 more cars could be set at an angle along 
that wall, making a total of 35. When cars are set at an angle like 
this, however, the projecting corner of each car makes a bad point to 
pass, as this corner is a fender, which is a rather weak unsupported 
part. This arrangement, too, cuts down the available aisle to a 
space scarcely sufficient for cars to pass through, certainly not 
enough for them to pass through at speed. 

Layout 8. Both the above arrangements provide for car storage 
and small accessories only, one having a repair shop, with battery- 
charging and tire-repair facilities, but neither having car sales space. 
A layout with slightly more floor space is shown in Fig. 11. This 
layout is an irregular space having a tapering corner which renders 
it doubly interesting, and space is provided for painting and trimming, 
also for a small car salesroom, and for an additional store that could 
be rented. The car space will store an even 40 cars, while the repair 
shop provides space for 6 more, and the paint shop and the trim room 
can accommodate 2 cars each, thus making room for a total of 50 
cars in the establishment. 

The building is on a corner and has entrances on three sides. 
If the prospective garage man has a layout like this, and if it were 
desirable to make it yield more revenue by adding storage space, 


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the elimination of the store and the small office corner would allow 
storage for about 8 more cars in that space. In figuring this space, 
however, the net additional revenue from 8 cars would have to be 
balanced against the net revenue from the rental of the store. In 
this layout, where the offices are at the front and the paint and 
trim shops are at the rear, the cars enter from the street at the right, 
while the other cars can enter either at the front or at the rear through 
the repair shop. Consequently, the space at the rear end of the 

Fig. 11. Combined Garage, Salesroom, Paint, Trim, and Repair Shop on Irregular Corner 
Courtesy of " Motor World" 

right portion of the building could be used for two more cars, as 
the dotted lines show. These two changes w y ould bring the capacity 
up to 50 storage cars, w r ith 10 more cars in the three shops, so there 
w r ould be a source of revenue from a total of 60 cars. 

As the tapering corner is the part that gives the trouble, layout 8 
might be improved by using this irregular portion for the three 
shops. If a partition were run from the back to the front, between 
the door and the window in the far corner and parallel with the 
right side until it met the present office lines, it would leave a car 


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storage space 85 x 60 feet, with square corners and three entrances. 
It would also give all the office space of this layout and allow the 
shops more floor space than they have, that is, over 3400 feet as 
compared with over 3000 feet. This layout, shown in Fig. 12, by 
narrowing down the present aisle from the street at the right and 
putting in another double row toward the back would permit storing 
47 cars. In addition, two more cars could be put in the corner 
where the two aisles meet, thus giving storage for 49 cars as compared 

Fig. 12. Rearrangement of Medium Garage Shown in Fig. 11, to Give More Regular Car Space 

with the present 40, and yet retaining all the present advantages. 
This might seem a small amount for so much trouble, but it can be 
figured as follows; If one car pays a minimum of $20 a month, 
which is $240 a year, 9 cars would add $2160 a year or, in round 
figures, $2000. At the same time, all three repair shops have more 
space than previously, and the garage space is cut down to a rec- 
tangular shape, with four square corners, making it easy to arrange, 
use, and keep clean. This rearrangement also makes the garage 
portion more accessible for cars, despite the fact that the front 
street entrance is eliminated in so far as the garage portion is concerned. 


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General Characteristics. A garage is considered large which 
has in excess of 20,000 feet floor space, that is, while the small garage 
would have about 5000 feet, and the medium size garage somewhere 
near 10,000 feet, the larger form would be about twice the size of 
the medium, or four times the size of the small garage. As a general 
thing, there are few garages of this size, which would work out at 
somewhere between 60x340 for the longest and narrowest shape, 
and 150 x 150 for the square, that is, when a garage has sufficient 
business to warrant this much floor space, it is in a section where 
the land is too valuable to be used in the form of a one-story building, 
for which reason most of the large garages occupy two stories, two 
stories and basement, three stories, or even more. This immedi- 
ately brings in a point not previously touched upon, namely, the 
method of handling the cars on other floors than the ground floor. 

Elevators vs. Ramps. In garages of more than one story, the 
cars are handled in one of two ways, by means of elevators or by 
inclines called ramps. Ramps have come into use in the last few 
years, and present the following advantages: They are usable at 
will, at any time of the day or night; the attendant and the machinery 
to run the elevator are eliminated, as is also the danger from the open 
pit. The ramp minimizes the fire hazard, which the elevator shaft 
always increases by providing a natural chimney, while ramps are 
never continuous from basement to top floor, and are made of concrete. 
On the other hand, they take up more space on all floors than 
elevators. Where the layout of the building allows it, however, they 
are considered a better investment. Certainly, from a service view- 
point, ramps can and do render much quicker and more efficient 
Service than any number of elevators. They are said to cost less, 
for the increase in the building cost is more than offset by the saving 
in the cost of the elevator and its machinery. 

In the large garages to be shown and described, some have 
elevators and others have ramps, and although no direct means of 
comparison is afforded, an analysis can be made in every case, and 
the question of which method would have been better can be settled. 

Typical Arrangements. Layout 9. Fig. 13 shows a one-story 
garage of the amount of floor space which entitles it to be called 
large. It is an old remodeled building with a width sufficient to 


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allow the arrangement 
B, shown in Fig. 1. 
With this arrangement 
the building has room 
for 100 cars. There is 
provision for a small 
store, a stock room, 
office, toilets for men 
and women, wash rack, 
also fuel and oil pumps. 
The latter are placed 
at the street front, just 
inside the door. The 
building, although as 
long as the average 
block is deep, does 
not run through to 
another street, so there 
is no back entrance. 
This plan makes it 
possible for some cars 
to be placed at the 
back end of the aisle 
against the rear wall 
and as far forward as 
seems advisable, as in- 
dicated by the dotted 
lines. Despite the 
number of windows on 
all four sides, it is 
advisable to have 
several skylights in a 
building of this size 
and shape. In an old 
building altered for 

garage use, the better way is to cut the skylights through the roof. 
Use of Basement. This layout, beyond its unusual length, 

shows few, if any, features. It has, however, everything on one 


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floor. When it comes to building several stories, the question arises 
as to whether it is cheaper to excavate a full basement and use that, 
or to merely go down far enough for foundations and build one story 
higher to offset the lack of a basement. In a specific case where 
three floors are needed, they can be obtained by the use of a basement 
and two stories, or three stories above ground and no basement. 

The question of which construction is better must be settled 
by local conditions. If the general increase appears to promise a 
need for more space in a few years, the basement and two-story 
building would provide the three floors for the present need, and the 
walls could be made heavy enough for the addition of one or more 
floors above, later. On the other hand, the three floors might repre- 
sent the limit of future expansion, that is, as far as the garage man 
could see ahead, while excavation was high priced, or the site con- 
tained rock or something of that sort. At any rate, it is a question 
to be settled in advance, for the basement cannot be put in after 
the building is erected. 

Steady boarders do not like the basement unless it is unusually 
well lighted and kept very clean. But this is not a great disadvantage, 
as there are many things about a garage that patrons do not like. 
If a choice is offered between a basement with a ramp and a third 
story, the patron will take the basement every time. From the view- 
point of some garage men, the basement has the advantage of lacking 
in natural light, and there is a disinclination on the part of patrons 
whose cars are located there to work on them, consequently the garage 
gets more work than it would if all cars were on or above the ground 
level where the floors are well lighted and the owner is given to 
doing much of his own work. 

Layout 10. A three-floor garage with two elevators is shown 
in Fig. 14. This might be either a basement and two-story building 
or a three-story building. The layout includes a repair shop and a 
paint shop, located at the rear of the top floor for the best light and 
occupying the full width of the building. On the ground floor 
is a salesroom, accessory sales space, stockroom, office, a private .room, 
and toilets for men and women. In the car-storage space are two 
wash racks, located directly in front of the two side entrances. The 
lack of wash racks above the ground floor would appear to be a big 
disadvantage here, for the 54 cars on the second and the 33 cars on 


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the top floor would have to be brought down one at a time, washed, 
and then taken up again, or else not washed at all. 

Since a paint shop needs a form of wash bench, it would seem as 
though one should have been laid out on the top floor in connection 
with the paint shop and another on the second floor, to obviate this 
drawback. On the other hand, a garage of this type will often rent 
most of its entire top floor, totaling, in this case, space for 33 cars, for 
dead storage, the balance being occupied by cars to be repaired, for 
which there is not room in the repair shop. In this case, no washing 

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Fig. 14. Arrangement of Three-Story Garage, in Which Two Elevators, Side by Side, Are Used 

or other attention need be given the cars; so, in the usual garage, 
the need of light and heat would be eliminated. It is an excellent 
layout, and could not be improved upon for quantity or economy of 
space, unless the •ends of the aisles at the front and back of the 
building were used. As the dotted lines show, this would add room 
for four cars on the second floor and two on the top. 

Improvements of Layout 10. The elevator arrangement in this 
building might be criticised on the ground that the two elevators are 
so close together and so located in the middle of the building as to 
be no better than one, except for frequency of service. As they are 


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placed, they take out the space of three cars on every floor. If they 
had been placed back in the corner at the rear, only two cars each 
would have been displaced on the ground and second floors, but the 
paint shop arrangement would have been upset, and there would still 
have been the objection of two elevators side by side being little better 
than one. If the elevator nearest the front were left where it is, and 
the other one moved back to the rear corner; the two cars displaced 
on the ground floor would have been offset by the three which could 
be added at the present position, thus gaining one. On the second 
floor, the two cars displaced would just equal the two which could 
be added, while on the top floor two cars would be added, so that the 
net result would be 3 car spaces gained. In addition, the paint, 
repair shops, and the second floor would get better elevator service. 
Layout 11. A typical city garage, built on a very narrow lot, 
so narrow that the garage floor space is not economical, is shown in 
Fig. 15. This is the first-floor plan, as the basement is not used for 
cars, although the three upper floors are. The arrangement shown, 
with the office, clothes closets, and toilet in one corner at the front, 
the entrance on one side, with the elevator at the rear on the same 
side, the wash rack alongside the elevator, and the stairs close to the 
wash rack, all cut into the space so that but 19 cars can be housed. 
If the building were a few feet wider and had the entrance in the 
middle, the cars could be lined up along the two walls, in which case 
the single floor capacity would be in excess of 32 cars. On the upper 
floors this is actually done, as a large percentage of the vehicles are 
taxicabs, the owner of this garage being interested in a taxicab 
company. These taxicabs are small, being shorter than regular 
touring cars, and therefore need less space for standing room and for 
maneuvering. As a result, the second floor houses 30 cars, the third 
floor 30, and the top floor about 10, the balance of this floor being 
given up to the repair, paint, and trim shops, and to cars waiting to 
be put in shape. There is a wash rack on both the second and the 
third floors, immediately above the one shown on the ground floor. 
The whole makes a convenient arrangement, considering what the 
building is and the impossibility of lengthening or widening it, or of 
making any other material change. Fig. 16 shows a photograph 
taken on the ground floor, and Fig. 17 shows one of the upper floors. 
These pictures show no crowding, as they were taken during 


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the day when nearly all cars were in use, so that by comparison 
with its total number of machines, the garage was almost empty. 








Layout 12. Another garage of about this same total capacity is 
shown in Fig. 18, but this is both wide and deep, and has a basement 


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which is used. The connection from ground floor to basement is by 
a ramp along one wall, but so placed as to have direct access to the 
street. There is provision in one corner for $ small car salesroom, 
an accessory salesroom, stock room, private office, and a general 
room, also an aisle to the shop, off of which are the toilets, as well 
as a fair size store for renting. On this floor are also two wash racks 


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Basement and Ground Floor of a Large Oarage, Using Ratnpa 
Courtesy of " Motor World" 

and a fair size repair shop. The basement has no provision except 
for cars, and a furnace room in one corner, which houses the heater 
and the coal. It accommodates 50 cars, despite the ramp and many 
aisles. The capacity could be increased to 60 cars, by putting them 
in the ends of the aisles against the walls and under the ramp. 

On the ground floor are three entrances, which give easy and 
quick access to the cars. The arrangement is good, compact, and 


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efficient, the ends of all aisles forming the wash racks. The capacity 
might be increased by taking out the store for renting and utilizing 
the space for cars. By making this change, 6 more cars could be 
accommodated. The present total is 35, and this would bring it up 
to 41. In considering this change, the revenue from 6 cars the 
year round would have to be balanced against the annual rent of 
a store of this size. The whole building now houses 85 cars, but 
with the suggestions made, it could handle 100, as it has 22,500 
square feet of floor space. This gives an average of 265 square feet 
per car for the original layout and 225 for the modification. As a 
car occupies but 15 x 7 feet or 105 square feet, it can be seen that 
this garage, which has a good average layout, is about 40 per cent 
efficient, and could be made 47 per cent. It is an unusually good 
layout which works out at 50 per cent, everything considered. 


When a garage can or does house in excess of 100 cars, or when 
its floor space is 30,000 square feet or more, it is not an exaggeration 
to call it a very large one. The very large garage is interesting beyond 
the other forms just described because its equipment is usually more 
complete, it possesses more facilities for doing work, its arrangement 
is generally studied out more carefully because of the enormous 
investment, and because of the number of cars which must be over- 

Typical Arrangements. Layout 13. An unusually large garage 
is shown in plan view ki Fig. 19. This is unusual for the reason that 
it houses only 100 cars and a few odd dead-storage vehicles when its 
width and length would allow the handling of almost twice that 
number with ease. It is one story high, without a basement, and has 
a chauffeur's room, a toilet, an office, a storeroom, and a wash rack, 
all housed in an L near the center of one side. Aside from vacuum- 
cleaning machinery, the balance of the entire floor, which runs clear 
through a city block, is available for cars. This space is 88 feet 
wide and 275 feet long, sufficiently wide for an arrangement like C, 
Fig. 1, with an additional width of 8 feet in the center aisle. This 
arrangement provides for 4 cars per 7 feet of length. The garage shown 
is 275 feet long, so there could be 39 such strips. Even if 2 cars were 
omitted to make room for the vacuum machinery, and 4 more in 

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front of the office and wash rack, there would still be space for 150 
cars with -a central aisle of unusual width. The garage actually has 
100 and will take no more. 

Use of Vacuum Arrangement. The vacuum machinery is an 
unusual feature. It removes all dirt and dust from all cars. The 
machinery is connected to each car space by means of a 2J-inch 
pipe, while a removable hose with a nozzle is carried around by the 
workman. Another unusual feature is that the machine shop, which 
is large and unusually well equipped, is located two blocks away. 
In addition to its broad central aisle, approximating 58 feet with 
but two rows of cars along the walls, two very large central skylights 


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Fig. 19. Very.Large Western Garage Which Runs through the Block 

make it very light and airy. Another feature is that each car space 
has a steel locker 40 inches one way, so that the largest tires in use 
can be stored there with perfect safety. The arrangement of the 
entrances is well worked out. On the street at the right there is but 
one entrance, this being used for both entrance and exit, but on the 
other street, where there are two, one is used for entrance only, and 
other for exit only. 

Layout H. Another very large garage is shown in Fig. 20. 
This garage has a shape not unlike the one shown ill Figs. 11 and 12, 
and the size is not radically different, being 100 feet wide by from 
100 to 154 feet long, an average length of 127 feet. It differs from 
the other in that perhaps 50 per cent of the ground floor space is 
given over to salesrooms, offices, elevators, and apparatus, and also 
in having four floors and a roof; the roof is a special feature to be 


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spoken of later. This garage was built for and is run in connection 
with the sales agency for one of the largest cars, hence -the amount 
of space given over to the salesrooms at the front of the building. 
While the single elevator might be thought inadequate for a building 
of this size and height, in combination with the turntables provided — 

Fig. 20. Very Large New York City Oarage with Many Unusual Features 

two on the ground floor and one on every other floor except the roof — 
it is quite sufficient, and there is seldom, if ever, any waiting. 

The car capacity is 20 on the ground floor; 60 on the second 
floor; 75 to 80 on the third, which is utilized for dead storage; and 
from 40 cars upwards on the fourth, which has a large and very 


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well equipped repair shop; and 25 cars on the roof. The latter is a 
distinct feature never seen elsewhere. The building has a high 
ornamental coping rising more than 10 feet above the roof, which is 
covered with tile. Inside of this coping, around the two sides of the 
obtuse angle, that is, the south and west sides, a light roof has been 
carried in for 25 or 30 feet, making a protected space of that width 
along those two sides. As the elevator runs up high enough to serve 
the roof as well as the lower floors, cars can be placed in this space 
and be as well protected as on any lower floor, except against a driving 
rain or snow from the north or east, accompained by a very high 
wind. Even then it is doubtful if the car would get wet. This space, 
in summer months, is as good as space anywhere else in the building. 
The length of the roof along these two sides is such that the cars can 
be placed end to end along it and still leave over 10 feet of working 
space under the light roof. This gives a capacity, in round figures, 
of 150 cars on live and 75 to 80 on dead storage, or 225 to 230 cars 
total which the garage handles. About 50 men, exclusive of sales 
and office employees, are needed to handle this number properly. 

Prices for Service. The prices, which are those of the trade 
association, are about as follows: 


Runabouts below 20 h.p $20.00 

Touring care from 20 to 40 h.p 30.00 to $35.00 

Touring care over 40 h.p 40.00 

Roadsters over 40 h.p 30.00 to 35.00 

Landaulets, any power 30.00 to 35.00 

Limousines, any power 35.00 to 45.00 

Transient storage, per night, no cleaning 1.00 

Repair work, per hour 75 

Dead storage 10.00 and up 

Striking a rough average of the 150 cars on live storage at $30 
would give a monthly revenue of $4500, and the dead storage on 
the 80 cars at $12 would bring in $960 a month, a total of $5460 a 
month, or $65,520 a year. This estimate is exclusive of repair work, 
spare parts, accessories, oil, gasoline, grease, waste, etc., all of which 
would probably bring the yearly income up to $75,000. 

Layout 15. Another very large garage, interesting by reason of 
having ramps up to the third floor, is shown in Fig. 21. Not that 


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Pig. 21. Floor Plana and Sectional Elevation of Very Large Three-Story Garage Using Ramp* 

Courtesy of " Motor World" 


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ramps cannot be used as high up as desired (6, 8, or even 10 stories), 
but it is unusual. When a high building is considered, the elevator 
is usually thought best, while ramps have the preference in a low one. 
This garage, with its three floors, has almost exactly 30,000 feet of 
floor space, housing 127 cars and giving an average of slightly over 
236 square feet per car, as against the 105 considered necessary. 
This garage has an efficiency of 44.5 per cent. 

The ground floor has two unusually large show rooms at the 
front, on either side of an entrance, with an accessory salesroom and 
stock of parts back of one of them. At the rear are two more 
entrances, one central, the other to the ramp. The wash rack is in 
the center of the aisle, midway of its length, and thus handy from 
both ends. The second floor is very simple, with the ramp coming 
up close to one side wall, crossing the building and going on up 
alongside of the other wall. This influences the layout of the cars, 
which is square and very simple, with a wash rack at the end of the 
large longitudinal aisle. The third floor has the ramp coming up 
at one side near the end, while the repair shop is across the rear 
end. This combination calls for a broad center-aisle space and 
considerable other waste room. Even with this waste, the ground 
floor has spaces for 40 cars, the second for 50, and the third' for 37 
cars, outside of those in the repair shop. One car could be added on 
the second floor, and two or three on the third, without disturbing 
anything, as shown by the dotted lines. The sketch at the bottom 
shows how the ramps proceed from floor to floor. The big problem 
in laying these out is to balance the desire to save as much space as 
possible against the keeping of the slope within a reasonable figure. 
Of course, cars coming in under their own power can negotiate slopes 
up which it would be very difficult to push a car by hand. 


Income and Expense Estimates. As something has been said 
about costs and also about revenue, it will be well to take up the 
subject of financing. In this connection, the sets of figures in Tables 
I and II are of pertinent interest. A group of men planning a large 
garage in New York City brought the estimate of costs, as given 
in Table I, to the writer for comment. In this estimate it seemed 


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that everything was figured and figured properly, yet there was 
no profit. The amount left for net income, $6900, was but 2f per 
cent on the total investment, and was not considered an adequate 

Analysis of Actual Estimate. The writer was asked to go over 
the figures and see what was the matter with them. The biggest 
item was that of the building itself, and it was discovered that this had 
been figured at 18 cents per cubic foot, while good standard practice 
showed but 13 cents necessary in garage construction, and very 
serviceable garages had been built and were in satisfactory operation 
which cost but 12 cents per foot. As the idea here was to show an 
opportunity for large profit, the lower cost per foot was used as a 
basis for a revised estimate. This changed the building cost, the 
interest on the building while being built, the cost of obtaining a 
building loan on it, and, in the operating expense, lowered the annual 
interest charges. 

On the other hand, no allowance had been made for equipment, 
elevators being included in the building cost, and other equipment 
was considered as "not costing much , \ In the matter of the number 
of machines, the spaces had not been well planned, and a 
rearrangement showed how 290 machines could be housed instead 
of 165. The district selected being an excellent one, where there were 
many cars and not many garages, also where the opportunity for 
motor trucks was beginning to show up very large, the vacant space 
was cut down from 20 per cent to 15 per cent. The revenue per car 
was refigured on the basis of actual gasoline, oil, and other supplies 
which an average city car would have to have, and the profit figured 
from this. It substituted a more exact method for a lump sum 

Analysis of Revised Estimate. Table II shows the revised 
figures and indicates how the final profit of over 30 per cent was 
arrived at, this being over and above the 6 per cent interest on the 
money invested. In looking these figures over in the light of present 
conditions, it would seem as though fewer elevator men would be 
needed, but this would be offset by the fact that the office force seems 
inadequate for a building of this size and for the handling of such a 
large number of cars — almost 250 — with the attendant number of 
book accounts. 


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Five-Story and Basement Oarage 


Ground $60,000 

Building (1,000,000 cu. ft. at 18 cts.) 180,000 

Architect ." : 2,000 

Interest on ground during construction 1,600 

Interest on building during construction 2,400 

Taxes and insurance during construction 1,000 

Cost of obtaining loan 5,000 

Incidental expenses 3,000 

Total cost $255,000 


5 Stories, 30 machines each at $30 average $54,000 

Basement, 15 machines at $30 average 5,400 

Gasoline, oils, etc., profit per month on each 

machine, $5 9,900 

~™~ $69,300 

Running 80% full (deduct J) 13,860 

Total income. $55,440 


Interest at 6% on $255,000 $15,300 

Annual taxes and insurance 4,500 

Electric current for elevators, etc 3,600 

Monthly supplies and sundry expenses 1,800 

1 Day superintendent at $150 per month 1,800 

1 Night superintendent at $100 per month 1,200 

1 Bookkeeper and stenographer at $75 per 

month 900 

8 Elevator men at $40 per month 3,840 

10 Floor men at $70 per month 8,400 

10 Washers at $60 per month 7,200 

Total expenses $48,540 

Estimated Net Income $6,900 

In submitting this second estimate, the writer made the point 
that the territory in which it was proposed to build this garage was 
a rich field for an electric garage, so that by investing an additional 
$6000 for switchboard, wiring, and plugs, and adding an electrician 
at $100 a month to the payroll, at least one-third of the capacity 


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Five-Story and Basement Oarage 


Ground $60,000 

Building (1,000,000 cu. ft. at 12 cts.) 120,000 

Equipment 12,000 

Architect 2,000 

Interest on ground during construction 1,600 

Interest on building during construction 2,000 

Taxes and insurance 1,000 

Costof loan 4,000 

Incidental expenses 3,000 

Total cost $205,600 


65 Cars a floor, 5 floors, at $30 a month per car $99,000 

15 cars in basement at $30 per car 5, 400 

Sale of gasoline on basis of 8 gallons a car per 

day, 3 cents profit on a gallon 17,000 

Sale of oil, grease, and supplies at an average 

profit of 5 cents a car per day 3,500 

Other revenue from rental of lockers, repair 

parts, charging, ignition, vehicle batteries, 

etc 2,000 

Totalincome $126,900 

Deduct 15 per cent for space not filled 19,035 

Total yearly revenue $107,865 


Interest at 6 per cent on $205,600 $12,336 

Annual taxes and insurance 4,500 

Electric current for elevators and for charging 3,000 

Monthly supplies and expenses 1,800 

1 Day superintendent at $1 10 per month 1,320 

1 Night superintendent at $1 10 per month 1,320 

1 Bookkeeper and stenograper at $75 per month 900 

6 Elevator men at $40 per month 2,880 

10 Floor men at $70 per month 8,400 

10 Washers at $60 per month 7,200 

Total expenses $43,656 


Yearly income, as above $107,865 

Yearly expenses, as above 43,656 

Yearly Profit $64,209 


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would be taken up by electrics which would yield $50.00 a piece a 
month for pleasure^cars, and the following rates for trucks: 

100O-lb. capacity $40 per month 

2000-lb. capacity 45 per month 

30OO-lb. capacity 60 per month 

2-ton capacity 55 per month 

3-ton capacity 60 per month 

4-ton capacity 65 per month 

5- and 6-ton capacity 70 per month 

On this basis, an average figure would be around $54 a car for 
the electrics, at which rate 82 (one-third the net capacity kept filled 
constantly), even after deducting one-third from the table allowance 
for rental and for gasoline and oil sales, would add a little over $10,000 
to the annual receipts, and only $1200 plus the extra interest of $360 
on $6000 to the running expense. The net result, all things considered, 
would be to increase the rate of profit on the increased investment 
and over the interest charge to 34.3 per cent. This showed that it 
would be a profitable proposition to consider the electrics, which 
had not been given a thought previously. 

This is about 32 per cent profit on an investment of $205,600, 
over and above the 6 per cent interest figured in above Tables I and II. 

While these figures represent a big car layout and city conditions, 
the average which can be worked out from them is not very far off 
for any kind of an installation. Thus, the original investment of 
$830 per car housed cannot be lowered very much. Using this 
estimate as a basis, a garage large enough, say 50 x 110 feet, to house 
30 cars would necessitate a total investment of $24,900 or, in round 
figures, $25,000. Experience has shown that this is not a bit too 
much. The average income per* car is put down at $440 a year, and 
the average cost of operation per car housed at approximately $100. 
The income for a typical 30-car layout would give a total of $13,200, 
and the cost of operation is $3000. It is doubtful whether a 30-car 
garage could be run on this low basis of cost, which shows the economy 
of having the larger institution. On this basis, the small garage 
could have but one bookkeeper and stenographer at $40 a month, 
and one floor man at the same figure, with the owner acting as both 
day and night superintendent, washer, etc. On a small layout of 
this kind, it is a question whether the cost of operation per car would 


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not run closer to $200, while the revenue per car, owing to the 
considerable number of small cars, would probably come down as 
low as $300. 

The amount of money to be invested, in addition to the cost 
of the building and its equipment, should be such as to carry on the 
business for a reasonable length of time, even without any income. 
Too many garages have been started without this capital, going on 
the assumption that motorists had plenty of money and would pay 
promptly upon receipt of bills. This is not true enough to be laid 
down as a rule or to be counted upon. So the garage man who is 
just starting should have enough cash to carry his establishment for 
several months without any income. It is not urged that the building 
and lot be kept entirely free and clear, or even that it be owned, 
but some capital, considerable, in fact, is a necessity. 


Building Materials. It would be unwise to specify any one 
material as the best, regardless of location, conditions, or amount of 
money involved, for practically all the materials used for other 
buildings are used also for garages. Among the materials which are 
widely used are: wood; steel; wood and steel; concrete in solid or in 
reinforced forms; hollow tile or other tile, usually stucco covered; 
concrete, in combination with any or all those given previously; 
brick; stone; brick or stone combined with any or all the others; 
and glass combined with any of the others. 

The kind of material to use should be selected according to (a) 
its first cost, balanced against its probable life and depreciation 
costs; (b) its availability, which is generally governed by local 
conditions and which has a very large influence upon the cost; 
(c) its fireproof qualities and their effect upon maintenance charges, 
through the insurance rates; (d) ease of erection; (e) architectural 
appearance when completed; and (f) general suitability to the garage 

First Cost. The cheapest material might be the shortest in 
life so that depreciation charges would be the greatest; on the other 
hand, the material which was most expensive in the first place might 
last the longest and thus have the smallest annual charges for deprecia- 


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tion and repairs. These things have to be considered and balanced 
one against the other. That form might be said to be the best in 
any case, which showed the greatest number of advantages in all 
respects. For instance, wood was formerly a very cheap material, 
but now it is fast getting out of that class; in certain locations, it 
is even a very expensive material. On account of its short life, high 
depreciation, and other drawbacks to be brought out later, it would 
be a poor material to use. Under some circumstances, however, 
wood is so cheap that nothing else can compare with it, its first 
cost being so low as to overbalance its shorter life and greater depre- 
ciation. In a case of this sort, wood would be the very best material 
to use. These same general remarks may be true of many other 

Availability. Availability has been partly discussed above. 
When a material is freely available, it is sure to be cheap, whereas 
a material which is difficult to get is equally sure to be expensive. 
Beyond being plentiful, availability means also easy to order, easy 
to have delivered, easy to handle in loading and unloading, easy for 
workmen to handle and use, and of such a nature that no difficulty 
will be encountered in getting it to the garage site, regardless of 
where that may be. All these items count, each one has a value, and 
in determining the choice of material they should be taken into 

Fireproof ness. There is so much gasoline, oil, and other 
inflammable material around a garage that fire is always a possibility. 
Garage insurance rates are high and always cut a big figure in the 
annual running charges of the garage, so that a wise man will consider 
these in detail before building. Not alone is fire a source of danger 
to the garage building, but it is also dangerous to the business, and 
indirectly to the garage man through his customers' cars, as the owners 
of the cars might sue if a fire occurred. From this point of view, 
the all fireproof building is the best, but the materials differ. All 
concrete construction, with metal window sash and door frames, 
probably comes the nearest to being fireproof; but all brick, with, 
concrete floors and metal sash $nd door frames, is almost as good, as 
is also the hollow-tile stucco-covered form and the stone or structural- 
iron framework, covered with tile or brick, as well as various other 


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Here again, the relative advantages of each material must be 
balanced, and that one selected which has the greatest number of 
good points, also the preceding qualities must be considered, as well 
as those which follow. Thus, in a location where concrete might be 
admittedly the best on all counts, cement for making it might not 
be available or, if so, in such limited quantities as to make it difficult 
to erect such a building. A wooden structure, possessing the merits 
of being the cheapest, is often made semifireproof by being covered 
with galvanized iron inside and out, the combination possessing 
many real advantages despite its crudeness. 

Ease of Erection a Factor. Ease of erection is somewhat a 
matter of local conditions. For a contractor who knows his business, 
no one building is more difficult to erect than another. But there 
are conditions in which there would be difficulties in the way of 
erecting buildings, say of concrete, that would put this material 
entirely out of consideration. It will be admitted that bricks are 
easier to lay up than stone, so that the former would have an 
advantage almost anywhere over the latter. In a town lacking a 
structural iron works, steel or iron as a framework would undoubtedly 
be out of the question. 

Architectural Appearance. Architectural appearance has been 
considered all too little in the past, both as regards the appearance 
of the material and in the matter of design of the building. With 
reference to the appearance, it will be admitted that wood does 
not have a good appearance for garage use, especially when it is 
covered with galvanized iron, as in the example just given. Sheet 
steel does not appear well either. Solid concrete does or does not 
appear well, according to the method of handling. Brick presents a 
good appearance if handled well, but it can be so handled as to have 
ugly outlines. Stone usually presents a good appearance; and also 
the combinations of brick and stone; brick or stone with glass; 
concrete with brick or stone, or with wood in the form of half timber- 
ing; and other forms. In short, almost any form can be made to 
present a splendid appearance, regardless of the appearance of the 
material itself in the raw state. 

With reference to the general appearance of the garage itself, 
it cannot be urged too strongly that the garage builder employ an 
architect and let him design an exterior that will be both simple and 

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pleasing. Too many garages, like Topsy, have "just growed", and 
they look it. In going along the road looking for a place to buy 
some gasoline, or other supplies, 99 motorists out of 100 will stop 
at the best looking of two garages set opposite each other. Viewed 
from this standpoint, a pleasing exterior appearance is a commercial 
asset; it brings in business, therefore it has a value, and should be 
studied out as carefully as any other point in the garage design pr 
construction that will have an influence on the right side of the 

Typical Exteriors of Good Design. In this connection, some 
sketches of exteriors made from actual photographs of successful 

Fig. 22. Pleasing Garage Exterior Lines Produced through Symmetry and Disposition 
of Windows and Doors , 

garages will be presented, and the garage man considering the building 
of a new structure can study them out and see which appeals most 
strongly and why. Having determined this point, his existing or 
projected building can be modified to have these lines, in order to 
bring the same success. 

Fig. 22 shows an ornamental and pleasant front obtained by the 
arrangement of the windows in large and small units. Despite the 
straight lines, it is regular and symmetrical. The building is of 
brick, with a front of white-faced brick, on which the name appears 


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in gold letters. The ground floor is of cement, the second floor 
double J-inch Georgia pine laid at right angles. All ceilings and 
partitions are covered with pressed-sheet steel, enameled white. 
The roof is flat and has two skylights. It measures 60 x 100 feet 
and holds 75 cars. 

Another brick building is shown in Fig. 23. This is one story 
higher, and the roof overhangs the third story, giving a pleasing touch. 

Fi«. 23. Good Garage Front Which Was Brought about by the Use of Tapestry Brick, 
Concrete, and Tile on Simple Lines 

The front is of tapestry brick, with tooled cement trimmings and 
columns. The roof tiles are semicircular in form and green in color. 
The building is fireproof throughout, with metal sash and door frames. 
Such a large part of the building is used for show room and salesrooms 
that the garage capacity is small. 

Fig. 24 shows another brick building in which a considerable 
amount of glass gives the structure an open pleasing appearance, 


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! Fig. 24. Large High Garage with Big Capacity, Yet of Pleasing Appearance Owing to 
Neat Lines and the Free Use of Glass 

Fig. 25. Ornamental Overhanging Roof Lines and the Rising Central Portion Break Monot- 
ony of Straight Lines and Give this Garage a Good Appearance Which Draws Trade 


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at the same time increasing the interior light in a marked manner. 
Floors are made of cement. The front shows what can be done 

with perfectly plain mate- 
rials and plain straight 
lines. The garage shown in 
Fig. 25 is built of brick on 
a steel framework, while 
the roof, having many sky- 
lights with wire glass, is on 
ste,el trusses. The orna- 
% mentation by means of the 
„ raised center, curved lines, 
a overhanging [tile roofs, and 
jl small overhanging ledges of 
^| red tile above the two 
|!§ symmetrically disposed 
§* entrances, all combine to 
~< make a pleasing building to 
J3*| look at, and one which the 
1 1 people of the neighborhood 
1<5 would not object to. The 
^J floor is made of concrete. 
1 9 The size is 88x275 feet, 
13 and it houses slightly over 
m* 100 cars. 

« The garage in Fig. 26 is 

| attractive because of its long 
& low lines, its Spanish Re- 
naissance style of architeo 
. ture, the very large windows 
* on the ground floor, and the 
symmetrical disposition of 
all windows, the whole build- 
ing being symmetrical about 
a center line. It is faced with 
tapestry brick, has an over- 
hanging red-tile roof, and is set back 50 feet from the street. The walk 
is of tapestry brick, the car entrance being on the side street occupying 


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a prominent corner. The floors are of concrete, the entire building being 
of brick and reinforced concrete. It measures 162 x 260 and houses 
over 120 cars, besides giving up the whole front to the offices and 
showrooms. The rear, or garage, portion is but one story high. 

A western garage is seen in Fig. 27, having a bold front of 
stucco and red tile in the Mission style. Its long low lines, the red 
tiles standing out from the dead-white stucco, the straight lines 
broken up by the ornamentation, with just enough curves added, 
and the symmetrical placing of all doors and windows make it very 
attractive to look at. The owners did this intentionally, and some 
one from that city has said of it: "Outside of its service, the bold 

Fig. 27. Stucco, Red Tile, and the Ornamental Touches Make This a Distinctive Garage 

pleasing front which is in harmony with adjoining buildings and with 
the evergreen park on the opposite side of the street, is the most 
valuable asset of the garage." The garage measures 80 x 80, all of 
which is for live storage except a 12 x 28 office. Forty-five cars are 
handled normally, but places have been made for 58. 

A southern reinforced concrete structure is seen in Fig. 28. 
It is of a Spanish type of architecture with an overhanging flat-tiled 
roof. It is on a prominent corner and has three stories and a basement, 
each measuring 103 feet square, all with cement floors. All the shops 
are located on the top floor, while a small part of the ground floor is 
used as salesroom and show room. 

General Suitability of Design to Garage Business. This means 
neither more nor less than proper planning. If the building has 

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been planned for easy entrance or easy exit and has an arragement 
that gives the washers the least amount of car moving to do, that 
provides for a large enough office so placed as to have supervision 
over all cars coming in or going out, with the oil room located where 
it is easy and convenient to all customers as well as to the workmen, 
with a location of the fuel tank at a point where it may be easily 
filled and customers easily supplied inside the garage as well as 
transients at the curb, and if it has all the other features which will 
make the garage easy to operate and which also will make for efficiency 

Fig. 28. An Example of What Can Be Done with Reinforced Concrete, When Well 
Designed and Suitably Ornamented 

and for a minimum of lost time and wasted steps, then it will be 
suitable for the garage business. If space allowed, it would be an easy 
matter to show how any one of these items, if overlooked, can bring 
about the failure of the business. It will suffice to say, however, that 
if entrance and exit are difficult, customers will not come in, or having 
come in once will not come again; if the arrangement makes the 
washers a maximum amount of extra and unnecessary work, it will 
be difficult to get them to do their work thoroughly, and customers 
will be displeased and will go elsewhere; if the office is too small, or 
so located that the incoming and outgoing cars cannot be observed, 


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there will be large losses; if oil and gasoline are not quickly accessible, 
people will go elsewhere to buy their supplies of these materials; so 
too, with many other features which might be mentioned, and, if 
these things are not well studied out in advance and provided for, it 
will not be possible to run the business on an efficient profitable basis. 


Major Equipment. Ordinarily, a person thinks of equipment 
as tools, supplies, and other means of doing work, but these might 
almost be called minor equipment in comparison with the major 
equipment. Major equipment might be listed as lighting, both 
natural and artificial; heating, which almost always means the 
individual heating plant for the garage, as there are few cities where 
heat, like electricity or gas, can be bought; ventilation, which may be 
incorporated in the building in part, or it may mean fans, blowers, 
and the like, in addition to those means which the building provides; 
water supply and provision for washing, in which the water supply may 
mean the installation of a pump, the provision of a special tank, 
power for driving the pump, etc.; drainage, which is closely allied 
with ventilation, for means must be provided for taking care of the 
fumes from gasoline, oil, kerosene, etc., which are dangerous and 
must not be allowed to reach city sewers; provision for power to drive 
machine tools, tire pumps, vacuum cleaners, buffers, etc. ; an elevator or 
a ramp and a turntable — provision for moving the cars up and down, 
if there is more than one floor, or around the garage; fuels and oils, 
greases — in liquid form and in cans or packages — and waste; benches, 
lockers, cabinets, racks, stands, and other similar things which might 
be called garage furniture; and, finally, tools, both large and small. 

Lighting. Natural Light. The interior width of the garage has 
a large influence on the number of windows needed for natural, 
and the number of lights needed for artificial, lighting. The narrower 
the garage, the easier it is to light it adequately by means of windows 
set close together on the sides of the building. But, as it widens out, 
the dark zone in the middle of the building becomes greater and 
greater until the point is reached at which artificial lighting is needed 
all the time, day as well as night. One of the axioms of building 
should be to keep the width down below the point where artificial 
lighting must be used day and night. 


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The location of the lot on which the garage is to be built, that is, 
whether it is between other buildings, on a corner, facing on three 
streets, running to an alley, etc., is important as regards the lighting, 
for plenty of natural light will be available in all these locations 
except in the first. The location in a downtown part of a large city 
has an unfavorable influence on the lighting situation, for it is almost 
a certainty that the light will be obstructed in one or more directions. 
The necessity for going higher up in the air, that is, building several 
stories high, brought about through the value of the land, makes a 
garage darker than would be the case otherwise. With a one-story 
building, many large skylights can be used, and these supply excellent 
light. An irregular shape is difficult to light if it is large; on the other 
hand, if it is small, it is very likely to have a greater area of outside 
walls relative to its interior or car space than would a regular shape 
and thus an opportunity for more windows than would ordinarily 
be the case, which would reduce the necessity for excessive interior 

Artificial Lighting. The garage man should study out all these 
things so Is to get the maximum amount of natural light, for that 
costs nothing, and to use the minimum amount of artificial light, for 
that is expensive. Electricity is the only satisfactory form of artificial 
lighting, all other forms having an exposed flame which will ignite 
gasoline and oil fumes. If a supply of electricity is not available, 
a small self-contained plant, with a gas engine and a generator set 
proportioned to the number of lights needed, and a set of storage 
batteries to equalize the supply and demand should be installed. 

There is a wide difference of opinion as to the number of lights 
needed. The writer would say that the equivalent of one 16-candle- 
power lamp is needed for each four cars. These lights need not be 
installed in just this way, but they can be grouped in threes, fours, 
fives, or sixes in such a way as to give a better total effect than the 
single bulbs strung out would give. In a large garage with sufficiently 
high ceilings to admit doing it to advantage, arc lights can be substi- 
tuted, on some such basis as one arc light to a very small floor, two 
to a small medium size, three for a medium or large size, and others 
according to the size of the garage and its needs. It is generally 
advisable to have very good light around the wash rack, as most of 
the washing in city garages is done at night. 


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1 ) 

1 ) 


Fig. 29. Four Methods of Piping a Garage for Heating Purposes 


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Heating. The idea of heating the garage is not alone to keep 
the water in car radiators from freezing, as many garage men seem 
to think, but also to make it a comfortable place for workmen and 
car owners to come into or to work in, and to keep the cars at such a 
temperature as will allow quick and easy starting. Many kinds of 
heating plants are available, but steam or hot water are the best, for 
with either of these the heat can be used to warm the water for washing 
the cars, thus making washing easier and quicker. If a lighting plant 
is necessary, the exhaust from the engine can be utilized, whether it 
be steam or gas. The exhaust may not be sufficient of itself, but it 
can be used as far as it goes, effecting a considerable saving. When 
either steam or hot water is used for heating, the radiators are 
generally made up of pipes, or else a wall radiator is used. A specially 
thin form for this purpose may be had. The radiators can be put in 
one of three forms, viz, pipes to and from a header, as at A in Fig. 
29; return bends, which may be either single, as seen at B, or double, 
as shown at C; and the wall radiator, shown at D. 

Ventilation. In a small garage, a ventilator on the roof, or two 
windows opened so as to create a draft through the building will 
suffice generally, but in a large garage it is advisable to provide a 
form of fan or blower, the fan to draw out the air, and the blower to 
force in fresh air. Either one can be placed in the upper sash of a 
window; so no special place need be provided. The open doors 
with their large area, the elevator shaft or the ramp, and the big 
open space of the interior generally make ventilation easy, but it is 
desirable to provide some mechanical means of changing the air and 
thus of being on the safe side. This is doubly necessary, for the vapors 
from gasoline, kerosene, and oils are explosive, while the exhaust 
gases are poisonous. 

Water Supply. For the city garage, water supply is simply a 
question of proper pipe connections and prompt payment of bills, 
but in the country it may mean much more. It may mean, for 
instance, the boring of a well before starting to build the garage 
and the installation of a pump to draw the water up from this well 
and force it to a large overhead tank. All this costs extra money. In 
planning the water system for a garage, it should be borne in mind 
that the water is used not alone for washing, for use in toilets, and 
for other personal uses, but it is also used for filling radiators, so 


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that a pure water with- 
out too much free lime 
is needed. The water 
system also forms a large 
part of the fire protection 
of the garage and should 
receive adequate con- 

Drainage. Garages 
need good drainage to 
carry off the water used 
in washing the cars and 
to carry away the gaso- 
line and oil drippings 
from the engine, trans- 
mission, axles, and other 
parts. The best way is 
to give the cement floors 
sufficient pitch to carry 
off the heavy stuff, and 
the drainage for the water 
will be very good. The 
arrangement should be 
such that all drainage 
will flow into a trap, or 
into several traps. Gaso- 
line will float upon water 
and will vaporize while 
laying upon it, while oils, 
greases, etc., will sink. 
A water seal on the trap, 
with a ventilating pipe 
connecting the surface 
chamber to the roof, car- 
ries off the vapors, while 
the heavier materials will 
sink to the bottom and 
will accumulate. Several 


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forms of traps are shown in Kg. 30. At A is shown a cast form, which is 
very rugged and is provided with both a ventilating pipe to the roof and 
a safety air space around the sewer pipe. At B is shown a homemade 
trap of concrete and of iron pipe. At C is shoWn another home- 
made form constructed from two sewer tiles, one with an L-outlet, with 
cement to close the bottom, and a cast-iron cover for the upper one. 

Provision for Power. If there is to be a machine shop, power 
must be provided, but even if there is no machine shop, there is 
generally a need for some power, as for the driving of the water 
pump, of the ventilating fans, of the air compressor, or of other 
units. If a lighting outfit is a necessity, it can be so arranged as to 
supply small amounts of power, either directly through belting, 
shafting, and pulleys, or indirectly in the form of electricity to electric 
motors. The indirect method is the preferred way, for it is simpler, 
cleaner, neater, more economical, and more up to date. If the 
garage is supplied with electricity, the question of power takes care 
of itself; in fact, it may work to reduce the lighting cost, as current 
rates are generally based upon the quantity of electricity used, 
the lower rate being given for the greater quantity. 

Provision for Moving Cars. The subject of elevator versus 
ramp has been discussed previously and will not be repeated here. 
The garage of more than one story must have one or the other means 
of moving cars up and down. In addition, all large garages should 
have turntables, as these save a great deal of time and space in 
arranging the cars in their places, and in getting them out when 
needed. By referring back to the illustrations previously shown, 
it will be noted that a number of the larger garages had a turntable 
provided on each upper floor, and two on the ground floor, all being 
in front of the elevator. This enables turning the car as it comes off 
the elevator or before putting it on so that it points in the desired 
direction. The elevator at the back of a building must have a turn- 
table to work with it, for every car would come in frontwards, and 
if it went on to the elevator that way, it would have to be backed off 
and, unless there was a turntable right there, backed to its place. 
Similarly, when being taken out, it would come to the elevator front 
end on, and when it reached the ground floor, the owner would 
not want to back it out. In such a case, a turntable saves double 
trouble with each car every time it comes in or goes out. 


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Fuels and Oils. Nearly all fuel systems nowadays are of the 
buried-tank type, with surface pumps. These systems have developed 
through the need of having the gasoline tank out of the way and 
protected from harm, also where it could be very large and conse- 
quently have a big supply. When it is considered that a car can 
easily use from 5 to 10 gallons of fuel a day, with the average around 
7, it is easy to figure what supply a 100-car garage needs to have, 
namely, 700 to 1000 gallons per day. When transient trade is added 
to this, such a garage should have provision for close to 1800 gallons 

Fig. 31. Bowser Remote-Control Fuel-Supply System 
Courtesy of S. F. Bowser Company, Ft. Wayne, Indiana 

a day. The mere handling of this amount is sufficient to keep one 
man busy, but, as it is profitable, the garage man should provide 
for it. Many systems are now in use, the most popular for large 
installations being like that shown diagrammatically in Fig. 31. 
Here, the tank is underground, outside of the building, while there 
is a pump in the basement, which is operated by an electric motor. 
This motor is set in motion by a lever at the curb stand, or draw-off 
station. This same general layout, but without pump and motor, 
is used in those systems in which the liquid is actually pumped by 
hand, through the rotation of a handle. 


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For use in and around the garage, it is desirable to have a smaller 
portable tank and pump, like that shown in Fig. 32. This tank has 
a capacity of about 50 gal- 
lons and makes it possible 
to fill cars wherever they 
are located instead of forc- 
ing the driver to come to 
the pumping station. This 
often saves time, as the 
attendant can fill the tank 
while the owner or driver is 
doing something else. It 
has been found to be both 
handy and economical in 
large garages. 

The garage man who 
desires such a form of under- 
ground gasoline tank, but 
cannot afford to buy one, 
should buy the components 
and make one. Such an 
outfit is shown in Fig. 33, 
although this one has a limited capacity. 
The tank must have three openings — filler, 
suction pipe, and pressure pipe. These are 
marked F, D f and B, respectively, in the 
cut. A large pump supplies the air pressure 
which forces the gasoline upward through 
pipe D when the cock E is opened. 

Fig. 32. 

Portable Supply Tank for Uae in and around 
tne Garage 



Fig. 33. Simple Arrangement of Outside Fuel Tank 

For handling oils, a different form of pump is needed. Oils 
are generally kept in a special oil room, and the different qualities 
are kept separated. Moreover, in comparison with gasoline, small 


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quantities of oil are sold, at a time. Aside from the fact that 
the receptacles are small and do not have wheels, the oil-supply 
system usually resembles a battery of units, like that illustrated in 
Fig. 32. 

Air-Supply System. Thus far, no mention has been made of a 
source of air supply, which is very necessary. Air is constantly in 
demand for inflating tires, and no up-to-date garage should be 
without it. In addition, it is handy for cleaning upholstery, for 
cleaning off repair parts, and in many other ways. The general 

Fig. 34. Four Different Air Supply Systems in General Use 

sources of supply are hand (or foot) power, which is inadequate for 
a large garage; electric power; and a belt-driven or engine-driven 
air compressor. Fig. 34 shows these three forms at A, B, and C, 
respectively, while at D is shown the steam-driven form, which is 
similar to railway locomotive compressors, and is a very efficient 
and compact form for use in large garages. Air compressors are 
now made in small sizes and mounted upon wheels, with electric- 
motor drives and lamp-socket connections, so that they can be 
wheeled around the garage to the desired position, then started 
and air supplied as desired. 

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Garage Furniture. The garage has need for many articles of 
wood and steel, such as engine stands, work benches, lockers, etc., 
which cannot be described .by any other name. These are really 
necessary, and the garage without them is not adequately equipped. 
In addition to the necessities in this line, there are of course many 
more which are desirable, which save time and space, and which 
are supposed to save money too. 
Also there is much of this kind 
of stuff that the handy man can 
make himself, that is, given enough 
equipment and furniture to start 
the garage, the handy man can 
make additional furniture and 
equipment as the demand { arises, 
thus gradually improving his place 
without much expense. ' The neces- 
sary furniture will be described first. 

There are so many different 
bolts, screws, and nuts around an 
automobile that a supply cabinet 
for these articles is a prime neces- 
sity. One of the best of these cabi- 
nets is. shown in Fig. 35. It 
consists of an eight-sided cabinet, 
each side of which has twelve 
drawers, so that a total of 96 
drawers of small size are provided 

11 Fig. 35. Useful Revolving Cabinet 

in a very small space. 

Practically the same thing, but in a different form, is the type 
of cabinet shown in Fig. 36. This has a large number of small 
drawers arranged in a horizontal plane. The form shown at the 
left is made with 54 drawers, the one at the right with 60. The 
case has a steel back, the drawers are made of galvanized steel and 
are dustproof. The larger drawers at the bottom are made with 
removable partitions. A pair of these cabinets set back to back 
make an excellent combination for a good size garage. The general 
run of drawer size in this form is so much larger than that shown 
in Fig. 35 that it would be possible to utilize both in the same garage, 




the one shown in Fig. 35 for small bolts, nuts, cotter pins, and similar 
very small parts, and the one shown in Fig. 36 for much larger parts. 
Other ways of producing the same results are by the use of made 
boxes, the idea being to purchase a supply of these boxes to suit pres- 
ent needs and to erect shelving to fit the boxes bought; then, as more 
boxes were bought, more shelves could be erected. These boxes are 
really well-made drawers, with locked corners, and are made in inter- 
changeable sizes so that one large, two medium, or three small, or 
still other combinations may be used on the same shelf. Unit steel 

Fig. 36. Excellent Type of Plain Cabinet for Small Parts, Bolta, Nuts, Etc. 

shelving is also used, the steel shelves, with drawers, if desired, being 
made up in a variety of sizes and shapes to fit the various needs. 
They are built on the unit system, so it is possible to buy a few for a 
start and add others as the business grows. 

Besides the cabinets for automobile parts are the lockers in which 
customers may hang their clothes, etc., and the various racks and shelf 
brackets or salesroom fittings to display and hold the various acces- 
sories which the garage sells. They may be made in any shape, 
homemade fittings being very serviceable, but the lockers are generally 


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made of steel. They are made in two forms, both of the same height 
outside. One form has the full height per locker, while the other is 
divided in the center, thus giving two lockers each of the half height. 
Both forms are made in several widths. 

Work Benches. The work bench is an important adjunct of the 
garage, and in every garage, unless it be a city place with a repair shop 
in connection, a work bench will be found at least along one wall. 
They almost always have a wood surface, usually of about two-inch 
lumber, but the framework is of wood and steel. The wood form is 
easy to make or to have the carpenter make, as it consists simply of a 

fig. 37. Garage Interior Showing Model Work Bench Layout and General Arrangement 

framework of four-by-four timbers, with a top of two-inch lumber and 
a facing, or corner board, of one-inch stock, and a tie, or brace, of 
about one by six stock below and close to the ground. If the bench is 
carefully designed, there will be a shelf underneath it for small boxes, 
and a series of these boxes will be made for small parts, replacing, in 
part, the cabinets spoken of previously. There should be one or 
more large drawers, also shelves or racks on the wall behind and above 
the bench. The bench height varies from 2 feet 8 inches to 3 feet, but 
2 feet 10 inches is about the average. An excellent example of this, 
although made with cast-iron supports for the ends, is that shown in 


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Fig. 38. Zinc-Lined Washing Bench, Which is Very 
Useful When Disassembling Cars 
'Motor World" 

Fig. 37. This shows not only the size, shape, and arrangement of 
the bench, but also the size and disposition of the drawers, location, 

and arrangement of the 
fixed and swivel vises, and 
the arrangement of the 
other tools and parts. 
Maple and birch are con- 
sidered the best woods for 

For cleaning parts, a 
special bench is desirable, 
and this should be lined 
with zinc, by preference, 
and have a tapering or 
sloping surface. It should 

Courtesy of " Motor World" fe l QWj ftn( J should be pro- 

vided with a drain so that oily parts can be deposited on the drain and 
the oil cleaned off and saved. The oil can then be filtered, and the 
better parts used again. Such a bench is illustrated in Fig. 38, which 
shows all of its construction, unless it is the braces needed underneath 
to stiffen it. These braces are desirable, for the bench often holds a 

very heavy load of parts. By mak- 
ing the squared section of the drain 
large, frequent draining is avoided. 
A further necessity in a garage is 
a small bench on wheels or on 
casters, stout enough to work upon, 
but not too heavy to be easily 
moved around. It should be a few 
inches lower than a regular work 
bench, which will also facilitate 
moving it about. Such a bench is 
very handy when disassembling or 
assembling a car or some of its 
units, since it gives a place to lay 
the parts as they are taken out, or to 
lay them out in the order in which they are to go together again, as well 
as a place on which to lay the tools which are being used. Sometimes 


39. Small Work Be «ch on Casters, 
a Very Handy L 'vice 


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these tables are made with a drawer and are oftentimes stout enough 
to cany a vise attached to the working surface. The simplicity of 
the construction of one of these benches is shown in Fig. 39. 

Special Stands for Units. Where the nature of the work is such 
that a good many units of one kind and size from some one machine 

Fig. 40. Handy Form of Engine Stand Constructed from Piping 
Couttuy of ShewaUer Manufacturing Company, Springfield, Ohio . 

are handled, it is advisable to have special stands made for them, as, 
inso doing, much work and trouble can be saved. Several such stands 

A portable unit-motor stand made of tubing is shown in Fig. 40. 
The oil drip pan and shelf arrangement at the open end are features. 
The disadvantage of this form, however, is that the unit motor sets 


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only in an upright position. This makes work on the crankshaft 
bearings and other parts on the under side of the motor difficult. 

A stand which will hold the engine unit in various positions is 
shown in Fig. 41. It is made by the International Motor Company, 
of Plainfield, New Jersey, for its own use, and is an excellent but 
expensive stand. 

A pair of stands are shown in Fig. 42. A is made of pipe fittings 
and angle irons and can be adjusted to the transmission or to the 
engine. B is a specialized stand for transmissions. The stands in 

(R) , >u^ (B) 

Fig. 42. Two Types of Handy Transmission Stands 

this figure have the disadvantage of holding the units in an upright 
position only. 


The tools for use in the garage may be divided into two general 
and widely different classes, hand tools and machine tools. In the 
former class come all those tools which are used, but which require 
nothing but hand power to drive them. In the second class come all 
those tools which garages have or should have, but which require 
power to drive them. 

Hand Tools. In the way of hand tools, which are too widely 
known and used to need any description, are: hammers, chisels, files, 
scrapers, punches and drills, clamps, reamers, taps and dies, meas- 
uring instruments, screwdrivers, saws (for wood), brace and bit, hack 
saw, jacks, wrenches, vulcanizers, breast drill, blow torch, oil stones, 
snips for cutting sheet metal, oil can and oilers, kit tire tools, spring 
leaf spreader, pliers, etc. 


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Vises. Vises as a means of holding work are very important and 
come under the heading of hand tools. While there are a number of 
different types, only two are used regularly, the plain bench vise and 
the swivel type. With the former, the jaws can only be opened or 
closed, but with the latter, the whole vise, including the work, can be 
revolved to a more convenient position. In addition, the latter type 
has a swivel jaw, a big advantage in gripping tapered work. By means 
of the locking pin at] the right end, the jaws are fixed in a parallel 

Machine Tools. The garage which does any work upon cars will 
soon require a few machine tools. This statement applies to the small 
shop that would not undertake regular machine work under any con- 
ditions. Such a shop should have, as a minimum, a lathe, a drill press, 
an emery wheel or other grinding means, with perhaps an electric 
motor having buffing and grinding attachments and of a portable type 
so as to be capable of use anywhere in the shop. 

Lathe. Of these tools, the lathe is the most important, and the 
small garage man with limited capital should pick this out with great 
care. It should be as small as will handle his work, although some 
of this work, notably flywheels and clutches, will require an 18-inch 
size. This fact immediately brings up a point which the garage man 
should decide in advance, and that is whether he will handle this big 
work or send it out. If he decides upon the latter method, his lathe 
size can be limited to a 10- or 12-inch machine. From a garage man's 
point of view, it is to be regretted that no manufacturer has ever seen 
fit to bring out a special model for this class of work, as there should be 
a market for hundreds of them. What a garage man needs is a two- 
purpose, or two-spindle, or gap-bed type of lathe, which would give a 
maximum capacity of 12 inches for all normal work, perhaps 360 days 
in the year, and a greater capacity, say up to 18 inches, for use one or 
two days a year, as for flywheels, clutches, brake drums, etc. A lathe 
of this kind is not made, however, so the next best thing is a high- 
quality plain engine lathe. 

Lathe Accessories. With a lathe, a considerable volume of acces- 
sories are necessary for handling a variety of work. It is advisable 
for the garage man to go slow in the purchase of these, until the nature 
of his work has shown the necessity for them. By this, reference is 
had to the various compound gears for screw cutting, different forms 


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of face plates, center and steady rests, chucks, mandrels, tool holders, 
tool posts, taper cutting attachments, tool grinders, boring heads, 
and other things. 

Drill Press. Drill presses are of three kinds, generally speaking, 
the sensitive drill which is too small and delicate for the range of 
average garage work, the usual drill press, and the radial type. The 
garage has little or no use for the latter type, nor for the modification 
of the standard form known as the multiple-spindle drill. A plain 
stout drill spindle which is made to a size that will handle drills up 
to and including J inch is all that is needed. 

Emery Wheel, or Grinder. The nature and quantity of the work 

would determine the 
size and quality of the 
grinding wheel to be 
used. A plaih rotating 
emery wheel can be used 
for so little, while a prop- 
erly selected grinding 
wheel can do so much 
work that is almost 
machining and, in this 
way, replace, perhaps, 
a planer, a shaper, or a 
milling machine, that 
the garage man should 
rypic&i power-operate Mack »*w wi«i make his choice very 

ttangeable Stroke Feature carefully. It is a Vdy 

handy tool, with many advantages over the ordinary emery wheel 
using the edge only for grinding. 

Hack Saw. The power-driven hack saw is an inexpensive tool, 
and even the smallest garage finds sufficient work to warrant its cost. 
It is useful for cutting all kinds of material into lengths, as, for 
instance, bar stock in square, round, or other form. It works almost 
without attention and will do more than three times as much work as a 
man with a hand hack saw can, do it much quicker, more neatly, and 
better in every way. In Fig. 43 is shown a power hack saw, which may 
be taken as typical, although there are many different sizes and styles. 
A feature of this saw, which is not common to all saws, is the adjust- 

Fig. 43. 


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able stroke. The disc which drives the saw is slotted, and the driving 
bolt in this can be set in various positions. When set as far out as 
possible, it gives the longest stroke, and when set close in to the center, 
it gives a very short stroke. 

One thing needed for, or rather with, a power hack saw is an out- 
board support for long work. Such a stand is shown in Fig. 44. It is 
simple and is easily made. 

F!g. 44. Outboard Stand for Hack Saw Facilitates Handling Long Stock 

Of almost greater necessity than the stand is a stop for the saw, or 
a power shut-off which will work when the cut is finished. Normally, 
a power hack saw is started on its work and left. In the press of 
other work, this work is often forgotten, and the saw completes it 
and then continues sawing idly at the air. To give a signal the device 
shown in Fig. 45 may be used; this consists simply of an electric bell 
connected to a dry cell in such a way that the dropping of the end of 
the work pulls the switch, thus closing the circuit so that the bell 
rings. When the work is put in and the saw started, all that is neces- 
sary is for the workman to attach the string to the end which is to be 

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cut off, with the switch open, taking care to have the string tight 
encugh so the dropping of the piece will open the switch. 

Grinding in the Lathe. 
Many a shop owner does 
not feel that the cost of a 
separate grinder is war- 
ranted by his work, even 
though he does have 
quite a little grinding to 
do. When this is the 
case, a grinder can / be 
rigged up on the lathe. 
This is done as shown in 
Fig. 46. The large pulley 
on the line shaft and the 
small pulley at the 
grinder give a sufficiently 
high speed. The lathe 
ways form a support for 
the work if it is large, 
while the carriage feed and 
cross-feed give a movement of 
the grinding wheel along or 
across the ways as needed. 

Milling in the Lathe. In 
using the lathe for milling 
purposes, the cutter is mounted 
on the spindle, and the work 
is placed in a special fixture 
which will allow an up and 
down movement. The carriage 
travel carries the work up to 
the cutter, the cross-feed allows 
feeding it across the face of the 
cutter, while the fixture gives 
an up and down feed. By this 
means, a considerable range of 

Method of Rigging up Grinder on Lathe i i_ j 

courted of "Motor World" flat surface work can be done. 

Fig. 46. 


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Utility of Portable Electric Motor. Mention of the utility of the 
portable electric motor in the small shop has already been made, but 

Fig. 47. Arrangement of Portable Electric Motor on Truck 
CourUry of "Motor World" 

this subject should be empha- 
sized. When a small portable 
electric motor is properly 
rigged up and used to its full 
extent, it is surprising how 
much good work and what a 
diversity of work it will do. 
For grinding, buffing, and 
similar work, the motor, with 
a flexible shaft, should be 
rigged up on a movable truck 
about as shown in Fig. 47. 
When the drilling must be 
exact, the motor can be 
mounted in a special vertical 
stand as shown in Fig. 48. 

Tool Equipment for 
Larger Shops 

Additional Tools. Usually 
the larger and more preten- 
tious shop will have a fully 
equipped repair shop. Such 
a shop would have all of the 

Fig. 48. 

Framework Which Allows Using Portable 
Electric Motor as Drill Press 


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tools that have been described, with their various attachments 
and accessories, and also a number of larger machine tools, which are 
necessary and are economical, or time saving, on larger or more com- 
plicated work. Some such tools are the planer shaper milling 
machine; milling cutter grinder and other special grinders, as crank- 
shaft and cylinder grinders; and arbor and other presses, etc. As 
these are in all respects identical with those found in any machine 
shop, no further explanation of their uses is given here. 

Other Tools. There are many other machine tools, but they are 
mainly modifications of the basic types which have been mentioned. 
Moreover, the garage man is not interested in them because they are 
high priced, and are not particularly adapted to his work. The main 
things the garage man should have in mind when buying machine tools 
is adaptability to his work and the necessary volume of work to 
warrant the expenditure. If all garage men would purchase their 
tools on this basis, and this alone, they would avoid much useless 
expenditure and equally needless extra overhead charges on account 
of idle machines. 


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Evolution of the Motorcycle. The same period which has 
brought the automobile to its present state of perfection has also 
witnessed the birth and development of the motorcycle. This two- 
wheeled motor vehicle was developed from the bicycle; in fact, the 
first motorcycles were bicycles with motors attached. However, 
owing to the comparatively high speed attained, the strains put upon 
the bicycle frame were too great, and extensive modifications were 
carried out, which resulted in a distinctive design and construction 
to stand the requirements of the service. It is significant of the 
general improvement in the construction that several motor bicycles 
have recently been designed and are giving good service. 

The motorcycle started entirely as a pleasure, or sporting, vehicle, 
used by a few bicycle enthusiasts who desired greater speed or by 
racing men for pacemaking. Gradually, however, the utility of the 
machine in many directions became established, and now its place in 
its own field is as surely fixed as that of the automobile itself. For 
single or tandem road work, for package delivery, for messenger 
service, for military duty, and for a hundred other important offices, 
it is unexcelled, and the thousands upon thousands of machines that 
are sold every year in this country alone bear testimony to its popu- 
larity. There are other indications in some recently developed types 
that the field of usefulness of this flexible machine will be broadened 
still further. 

Standard Specifications. The conventionalized American motor- 
cycle is of two-cylinder construction. The frame is tubular and 
diamond shaped, with a double crossbar at the top, between which 
bars are located a gasoline tank and an oil tank. At its lowest point 
the frame is in the form of a loop, in which is clamped the aluminum 
crankcase of a twin-cylinder air-cooled motor, with the cylinders set 
V-shaped and a carburetor fitted between. Separate exhaust pipes 
lead from each cylinder to a muffler. The motor is of the L-head 
type, with the cylinders, as a rule, cast in one piece. The exhaust 



valves are at one side of the motor and are operated by cams on the 
lower side of the crankcase. The same cam often operates both 
exhaust valves. 

In a removable cage on the roof of the valve pocket just over the 
exhaust valve, is located the intake valve, which is operated by a 
rocker arm above it, controlled by a push rod running up the side of 
the motor from the cam case. The crankcase contains two flywheels, 
which form also the crank arms of a built-up crank. Both connecting 
rods are fastened to the same crankpin, and these rods run down 
between the flywheels. 

In the cam case is a small plunger oil pump which pumps oil in 
small quantities to the forward cylinder, this oil being delivered 
through the wall of the cylinder directly onto the piston at the lower 
end of its stroke. From this point the oil drops into the crankcase 
and is thrown up through the rest of tlje motor by the splash system. 
The crankshaft on one side runs into the cam case, from which a train 
of gears drives a magneto for ignition. The advance and the retard of 
this magneto are controlled by twisting one of the handlebars of the 
motorcycle, this motion being ordinarily transmitted to the magneto 
through a series of bell cranks and rods. The throttle is controlled 
by twisting the opposite handlebar; so the control of the entire 
machine is always within the driver's grasp. 

The right end of the motor shaft projects beyond the right side 
of the case and ends in a small roller-chain sprocket, from which a 
chain runs to a larger sprocket on a countershaft set at the base of 
(or just back of) the vertical frame-tube member. Since change- 
speed gearsets are becoming common, this shaft is generally located 
back of the seat-post tube. The large countershaft sprocket connects 
with a small countershaft sprocket or with a gearset by means of a 
multiple-disc friction clutch, either of the dry fabric-faced type or of 
the metal type. This clutch may be operated by a lever in front 
of the driver's seat or by a foot pedal or by both. From the counter- 
shaft, a chain runs from a smaller sprocket to a larger sprocket on the 
rear wheel hub of the motorcycle. In this hub is located a brake (or 
brakes) of the expanding or contracting type or of both, operating on 
a brake drum. The rear end of the frame is often mounted on springs 
from the seat-post back, the lower frame forks being pivoted and the 
upper connection sprung. Within this triangle and generally back of 


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the seat post is fitted a tool box, while over the wheel a luggage carrier 
forms the stock equipment. A stand ife always fitted on the rear 
wheel to enable one to leave the motorcycle without its falling over. 

The saddle is very large, as compared with a bicycle seat, and has 
sensitive springs, as well as being mounted usually in a spring-seat 
post located in the vertical-tube member. This saddle is always 
placed as low as possible on the frame. The front forks are mounted 
on some sort of springs — generally of the flat-leaf type — in order to 
absorb the shocks and thus avoid metal fatigue in the machine as 
well as bodily fatigue in the rider. This, in outline, is the American 
motorcycle of today. 

Present Trend of Models. This outline is that of what might 
be called the American heavy-duty motorcycle. About 1914 or 1915, 
it looked as if this twin-cylinder type, with a change-speed mechanism, 
would soon displace all other designs. Later developments, however, 
have brought out several decidedly light-weight machines and at 
least two motor wheels, so that for 1917 there are more types than 
ever before. One set of riders has been demanding greater power and 
greater comfort in each season's models, until we have the expensive 
high-powered three-speed electric-lighted machines, suitable for all 
kinds of cross-country work; another class has been clamoring for 
a light machine of minimum cost both for initial price and for up-keep. 
These light machines are, of course, limited to city work and other 
more or less ideal conditions, but they are meeting the want of a large 
class of buyers. Many of the designs are very similar to the experi- 
mental machines developed abroad in the last few years preceding 
the war. 


Early Machines. The first motorcycle built was the work of 
Gottlieb Daimler, who in 1885 built a two-wheeled vehicle to try out 
a gasoline motor with which he was experimenting. This machine 
was the forerunner not only of the motorcycle but of the automobile 
as well. De Dion of France, with Karl Benz of Germany, developed 
along with the automobile the gasoline motor, and the De Dion type 
was soon applied to a motor tricycle, followed by a motor bicycle 
using the same motor. 

This motor was the predecessor of the motorcycle motor of 
today. The cylinder arrangement and the location of the compression 


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chamber were almost identical. Two flywheels were used, with a 
connecting rod between, and the flywheels were entirely enclosed in 
the crankcase. Viewed in the light of modern design, the motor was 
very crude but developed horsepower enough to drive this early 
machine at what was then considered an astonishing speed — 30 
miles per hour. 

• The foreign machines were developed between 1894 and 1898, 
when an American inventor, who had been building racing bicycles, 
took up the motor-driven tandem as a pace-making mount for bicycle 
racing. As the motorcycle is all wheel base and no tread, it has no 
difficulty in holding the road at any speed; a fact which made it 
very adaptable to this kind of service. The transmission of this 
machine, designed by Oscar Hedstrom, was the basis of the formation 
of a company for the manufacture of motor bicycles, with George 
M. Hendee as the business manager of the concern. At about the 
same time, the Thomas, the Holly, the Orient, and the Mitchell 
motorcycles were being developed. 

Two-Cylinder Motors. Glenn Curtiss was one of the first to 
develop a two-cylinder motor. It was in connection with his experi- 
ments with motors that he built a motorcycle equipped with an eight- 
cylinder V-type motor, which, covering a mile in 26.4 seconds — the 
fastest mile ever covered by man — held the record until recent date. 

The first motors built were small-power engines of about the 
same stroke as bore; they attained surprising speed and cooled very 
successfully with flanges of small area. 

Starting with 2.5-horsepower motors, power and weight were 
continually added until motors of 12- and even 14-horsepower have 
become common practice. The latter are, for the most part, of large 
bore and of comparatively slow speed, but, through the activity of 
European developments, light-weight machines with high-speed 
motors are coming into prominence. 

Influence of High-Speed Motors. In the early days, when 
materials and workmanship were questionable except at a great 
expense, high speed in a motor was a disadvantage and tended toward 
short life. Belt drive from the motor to the rear wheels was common, 
and hence motors could not be geared below a certain ratio without 
having the belt pulley too small to transmit the power. Flat belts 
became very popular in America and were used on such machines as 


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the Excelsior, the Harley-Davidson, the Yale, etc., while the Reading- 
Standard and the Indian factories consistently held to chain drive. 
Within the past few years, with the introduction of change-speed 
gears and high-speed motors, a positive drive has become a necessity, 
and chain drive with reduction to a countershaft located between the 
motor and the rear wheel has become almost standard practice. 
Foreign designers still favor the belt to transmit the power from the 
countershaft to the rear wheel, claiming that this gives greater flexi- 
bility of drive. American makers obtain smoothness of action by 
incorporating a slipping clutch in the transmission. 

Light-Weight Machine. First to bring into prominence the 
light-weight motorcycle and high-speed motor was the Douglas 
Company, of England, which built a small horizontal-opposed two- 
cylinder air-cooled motor — a success above 4000 r.p.m. by virtue of 
its almost perfect balance of moving parts. This motor was set 
fore-and-aft in a light frame, with a chain taking the power from 
the motor to a countershaft at the frame junction below. A 
V-type pulley was the front member of the belt-driven system, and 
the gear reduction of the first chain drive threw a minimum strain on 
the belt and hence proved very reliable. This machine weighed, 
complete, about 183 pounds, and yet it was capable of the same road 
performance as the high-power American machines of greater weight. 

In developing the new series of light-weight machines, already 
mentioned, the American designers have undoubtedly been influenced 
by the English successes along these lines. The single cylinder has 
been retained, and the two-cylinder opposed engine is coming rapidly 
to the front. 

Modern Improvements. While the light machines have been 
developing, the refinement of the standard twin V-type has gone stead- 
ily on. The greatest improvements of recent date have been toward 
making the motorcycle more comfortable, cleaner, easier to operate, 
more reliable, and more foolproof. This, in nearly every case, has 
meant an increase in cost rather than a decrease, but buyers prefer a 
completely equipped machine at higher prices to partially developed 
mounts at lower figures. Four-cylinder machines are becoming 
popular with each succeeding year, and the manufacturers are also 
incorporating three-speed gearsets, self-starting systems, and other 
automobile features to as great an extent as possible. 

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With the many improvements in construction, convenience, and 
reliability in the motorcycle has come a broadening of its field of 
usefulness. Fitted with a sidecar and with an extra wheel, it has 
become the family carryall or has been utilized for city runs and 
delivery purposes. In the recent wars, motorcycles have played a 
very important part in the transmission of messages and in the quick 
dispatch of repair men and scouts for emergency service. A number 
of the sidecar vehicles have even been fitted with machine guns and 
very successfully used for rapid reconnoissance work. 


Smith Motor Wheel. Although not a motorcycle in itself, the 
Smith Motor Wheel for attachment to bicycles has added hundreds of 

Fig. 1. Smith Motor Wheel Attached to Rear of Bicycle 
Courtesy of A. 0. Smith Corporation, Milwaukee, Wisconsin 

enthusiasts to the motorcyclist family. This wheel is a self- 
contained power plant consisting of a single-cylinder four-cycle air- 
cooled engine, having a bore of 2f inches and a stroke of 2J inches. 

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The engine is carried upon a bed which is flexibly attached to the 
bicycle frame, the motor wheel following slightly behind the rear 

3 •"» 

ci O 

wheel of the bicycle, as shown in Fig. 1 . One end of the engine crank- 
shaft carries the flywheel, while the other end is geared internally to 


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the driving wheel. The effect of this attachment is very much the 
same as that of the person running along the side of a bicycle rider 
and pushing him by means of the seat post, the connection between 
the motor wheel and the bicycle being quite flexible. This motor 
wheel has been adapted to all kinds of service, such as light delivery 

Fig. 3. Rear of A. O. Smith Buckboard 

vans and children's automobiles. The Smith Company has recently 
brought out a very light four-wheeled buckboard, Fig. 2, carrying 
two passengers and driven by the motor wheel. The rear connection 
of this model is shown in Fig. 3. 

Dayton. Using the same construction of power plant, the Davis 
Sewing Machine Company has developed the Dayton Motor Bicycle, 
which has a motor wheel suspended between the front forks in place 


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Fig. 4. Dayton Motor Bicycle Showing Power Plant in Front Wheel 
Courtesy of Davis Sewing Machine Company, Dayton, Ohio 

Fig. 5. Engine Side of Merkel Motor Bicycle 
Courtesy of Merkel Motor Wheel Company, New York City 


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of the ordinary front bicycle wheel, Fig. 4. The illustration also 
indicates the location of the gasoline tank on the handlebars. 

Merkel. Newest in the motor-wheel development is the design 
of Joseph F. Merkel, who is well known in the motorcycle world 
through the success of the Merkel Flyer. This Merkel motor wheel 
is a combination of single-cylinder engine and rear bicycle wheel. 

Fig. 6. Flywheel Side of Merkel Motor Bicycle 
Courtesy of Merkel Motor Wheel Company, New York City 

The engine is on one side of the wheel, Fig. 5, and the flywheel and 
magneto is carried on the other side, Fig. 6. The whole assembly is 
intended to replace the rear wheel of an ordinary bicycle, Fig. 7. 

Cyclemotor. Besides this crop of motor wheels and of motor- 
wheel applications, there has appeared again a group of engines to be 
attached to the frame of the bicycle, driving through a belt to a pulley 

278 Digitized by GOOgk 


added to the rear wheel. Some years ago the same idea was attempted, 
but, owing to mechanical imperfections, did not seem to be success- 
ful. The big advance, however, which has been made in the design 

Fig. 7. Complete View of Merkel Motor Bicycle 

Fig. 8. Side View of Cyclemotor with Belt Drive 
Courtesy of Cyclemotor Corporation, Rochester, New York 

and construction of small gasoline engines and in the accessories 
employed with them, bids fair to make a success of these newer 
developments; in fact, some of them have been on the market long 


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enough to have made a favorable impression already. A good example 
of this type of machine is the cyclemotor, illustrated in Fig. 8. 

Auto-Ped. It would be hardly fair to leave this crop of near 
motorcycles without mention of the Auto-Ped, which is a device on 
two wheels, with a small board between, and with an engine attached 
to the front wheel. The operator stands upon the board between the 
two wheels, as on a child's coaster, and controls the device through a 
handle which takes care of the steering. 

Light- Weight Motorcycles. No attempt will be made to describe 
or to even list all the light-weight machines that are now on the 
market. Short descriptions, however, will be given of the machines 
which are representative of a certain type of construction. In rela- 

Fig. 9. Excelsior Light- Weight Motorcycle 
Courtesy of Excelsior Motor Manufacturing and Supply Company, Chicago, Illinois 

tion to the light-weight movement, the two-cycle engine has come 
back into striking prominence. 

Excelsior. One of the best examples of the two-cycle engine is 
the Excelsior Light-Weight model, Fig. 9, which employs a single- 
cylinder two-cycle engine of 2^-inch bore and 2f-inch stroke, giving 
a piston displacement of 22.87 cubic inches. The ignition is provided 
for by a high-tension magneto driven by a silent chain, and the drive 
is through a two-speed gear and V-belt. The ratio on high speed is 
5 r* to 1 and on low speed 8H to 1 . This design shows well-developed 
springing and a kick starter. 

Indian. Of the two-cylinder opposed chains the Indian Light 
Twin, Fig. 10, is among the most interesting. The cylinders lie fore- 


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and-af t' at the bottom of a very large loop in the frame and are air 
cooled. The bore is 2 inches and the stroke is 2J inches, giving a total 



3 c 


■8 1 



piston displacement of 15.7 cubic indies. The Dixie magneto is 
mounted directly over the crankshaft. A three-speed sliding-gear 

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transmission, and a dry-plate clutch deliver the power to the final 
roller-chain drive. 

Thor. While cost of purchase and of upkeep have undoubtedly 
been the leading factors in developing these light-weight machines, 

lightness, for its own 
sake, has a strong ap- 
peal to a large class of 
riders, and the Thor line 
includes a light twin of 
the V-cylinder construc- 
tion, Fig. 11, in which 
I low purchase cost does 
5 not enter into considera- 
I tion. This machine has 
"! 5 cylinders with a 2 J-inch 
2 | bore and a 31-inch 
2 I stroke, ,or a total dis- 
!§ ^ placement of 38.6 cubic 
5 | inches, and is provided 
^ with a high-tension 
magneto and with all the 
other refinements of its 
brother Thor machines 
E a of double the horse- 
^ power. 

| Developments in 

| Standard Types. Two- 
Cylinder. So much for 
the general types repre- 
sentative of the new 
light-weight high-speed 
engine movement. 
Turning ta the more 
standard American ma- 
chines, we find no radical changes in the twin-cylinder V-models or in 
the four-cylinder machines. There are, however, the usual improve- 
ments and refinements, with a seeming tendency to decrease the 
number of models by discarding the two-speed gear and standardizing 


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- ^ 


the three-speed type. This is probably owing to the fact that every 
machine sold is more than liable to have a sidecar, a rear car, or some 
other kind of a car or freight-carrying attachment placed upon it, and 
the three-speed machine has now been developed to a point where it 
can adequately take care of this kind of service — a demand which, a 
few seasons ago, the makers were inclined to feel was an abuse. 
Fig. 12 shows the latest of the Harley-Davidson Twins, the engine 
having a bore of 3A inches and a stroke of 3£ inches, which gives it 
a piston displacement of 60.34 cubic inches. The dry-plate clutch, 

Fig. 12. Harley-Davidson Standard Twin-Cylinder Three-Speed Motorcycle 
Courtesy of Harley-Davidson Motor Company, Milwaukee, Wisconsin 

the three-speed transmission, the kick starter, and other features 
are not new, the only changes being slight refinements, which each 
season brings about. , 

In passing, it should not be forgotten that the large single- 
cylinder type, which was the predecessor of the V-type, is still on the 
market, although its demise was predicted several seasons ago. This 
is because a number of large public-service corporations have found 
this type so successful in their trouble departments that they insist 
upon purchasing more of them each season. The wide-awake com- 
panies, however, are beginning to look more favorably upon the twin- 

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cylinder three-speed machines for their heavy service, and there is no 
question but that the large slow-speed single-cylinder type will in 
time drop out of sight. 

Four-Cylinder. The Henderson Motorcycle Company, of Detroit, 
has been the successful champion of the four-cylinder design, 
Fig. 13. These engines are air cooled and have a bore of 2\ inches and 
a stroke of 3 inches, giving a piston displacement of 58.9 cubic inches. 
The Henderson has been on the market for several years, and the 
construction in the past has included a bevel gear at the rear of the 
crankshaft, which drove through a chain to a planetary two-speed 
transmission incorporated in the rear hub. For the coming season, 

Fig. 14. Side View of Militaire Four-Cylinder Motorcycle 
Courtesy of Militaire Motor Vehicle Company, Buffalo, New York 

this construction has been replaced by a three-speed sliding gear at 
the rear of the crankshaft, with a chain drive back to the standard 
types of hub and band brakes. One of the features of the four- 
cylinder machine is its very rapid acceleration, which makes it very 
easy to handle in traffic — excellent for police-department work. 

Another four-cylinder machine, the Militaire, has recently been 
announced, which is illustrated in Fig. 14. This carries an engine of 
2H-inch bore and 3-inch stroke, with a piston displacement of 68 
cubic inches. The specifications list such unusual features as a selec- 
tive sliding-gear shaft having three speeds forward and a reverse, 
which forms a unit with the engine. The drive is by propeller shaft, 


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Fig. 15. Rear View of Militaire Motorcycle, Showing Auxiliary Wheela 

in Position for Supporting Motorcycle 

Courtesy of Militaire Motor Vehicle Company, h uffalo, New York 

and the wheels are of artillery rather than wire type. In Fig. 15 
it will be noted that there are two auxiliary wheels which swing up 
off the ground; in their normal position, they lie at each side of 


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the rear wheel. These auxiliary wheels are lowered, as shown in the 
figure, when the machine is left standing or when it is driven in 
very slow heavy traffic where the motorcyclist so often has to drag 
his feet upon the ground. 


Nomenclature. Before going on with a discussion of engines and 
how to take care of them, it is best to make sure that the reader under- 


Fig. 16. Diagrams of Various Parts of Motorcycle 

stands the names and purposes of the various parts that go to make 
up the complete machine. When dealing with the principles of the 
internal-combustion engine, we always deal with the single-cylinder 
type for the sake of simplicity, pointing out that in the two-cylinder 




and four-cylinder engines there has been but a combination of several 
single-cylinder engines. 

Referring to Fig. 16, we have at A the cylinder casting, which is 
made of gray cast iron, although in some cases it does not look it, 
owing to methods of sand blasting, enameling, etc. The cooling ribs 
are cast integral and are not of a different material shrunk on as was 
tried on some air-cooled automobile engines. At B is the crankease, 
which is an aluminum casting, usually highly polished. Most 
automobile crankcases are split along a horizontal plane, but the 
motorcycle crankease is divided in the verticle plane and bolted 
together as shown. Piston, connecting rod, and flywheel assembly is 
shown at C. The piston moves up and down in the bore of the 
cylinder. It is usually made of cast iron and often drilled with a 
number of comparatively large holes to decrease its weight and also to 
assist in the lubrication of the cylinder wall. Aluminum is gaining in 
favor as a piston material because of its light weight. The purpose 
of the connecting rod is to change the back and forth, or reciprocating, 
motion of the piston into rotary motion at the crankshaft. This 
mean* that there are bearings at both ends. At the upper end, the 
bearing is called the wrist-pin bearing, because the small shaft across 
the piston is called the wrist pin. At the lower end, the bearing is 
known as the connecting rod bearing and the big end bearing. 

One of the main differences between the general design of the 
motorcycle engine and that of a small marine or an automobile engine 
is in construction. In the ordinary design, a one-piece crankshaft, 
as at D, is used, and this extends through the crankease w r ith the single 
flywheel E fastened on the outside, as in the Motor Wheel and in the 
Indian Light Twin. In all other motorcycle designs in this country, 
however, enclosed flywheels are used. In this case there is a flywheel 
on each side, as shown at F, these being housed inside the crankease. 
The counter weights to balance the inertia forces of the piston are cast 
as part of these flywheels instead of being fastened on as is sometimes 
done with automobile crankshafts. 

A valve assembly is shown at G, giving the valve, the valve seat, 
the valve spring, the tappet, and the cam. The valve usually has a 
bevel seat, as shown, but in some cases it is flat. As the cam is 
revolved by the gearing from the crankshaft, the high portion comes 
under the bottom of the tappet and raises it upward. The tappet, 


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in turn, raises the valve from its seat, allowing gases to enter or to be 
exhausted from the cylinder, as the case may be. There is often an 
arm, or cam follower H, interposed between the cam and the lower 
end of the tappet, but the general action is the same. 

It is quite common to use an overhead valve for. the inlet, and in 
that case the valve often, works in a removable cage H instead of 
seating directly on the cylinder casting. In order to get the action 
of the cam carried to the valve, the tappet raises a long push rod and 
this, in turn, raises one end of a rocker arm, the combination of motions 
opening the valve. 


Classification. Motorcycle engines of all designs are of the 
internal-combustion engine type, which means that fuel is burned, or 
exploded, inside the cylinder of the engine, where the heat energy 
liberated is transformed into mechanical energy. An example of an 
external-combustion engine is the ordinary steam engine, where the 
burning of the fuel takes place outside of the engine itself. 

There are two general types of the internal-combustion engine, 
known as the four-cycle and the two-cycle engines. Since these 
terms refer to che number of strokes of the piston for each power 
impulse for one particular cylinder, it would be more proper to speak 
of them as the four-stroke-cycle and the two-stroke-cycle, but custom 
has dropped the word stroke. 

Four-Stroke-Cycle, or Four-Cycle. Taking up the four-cycle 
operation first, as it is the more important so far as the number of 
machines is concerned, we will assume that the piston has passed the 
Upper dead center, as at A, Fig. 17, and that at this point the inlet 
yalve is well open. As the piston travels downward, the explosive 
mixture is drawn into the cylinder, and at the lower dead center the 
!nlet valve closes. As the piston travels back, both valves are closed 
B, and the mixture is compressed to from sixty to ninety pounds 
oer square inch. At the time the piston reaches the top of the 
stroke again C, the spark occurs at the plug, igniting the charge. 
The rapid expansion, or explosion, of tlie gases, drives the piston down, 
this being known as the power stroke. The other two strokes are 
called the intake, or suction, and the compression strokes. At the 
end of the power stroke the exhaust valve opens D, and as the piston 


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Section STROKE 

Compression stroke 

Power Stroke 

Fig.' 17. Diagrams of Various Operations of Four-Cycle Engine 
Courtesy of "Motor Age", Chicago 


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returns to the top position, the burned gases are pushed out through 
the exhaust valve. The cycle of events is then repeated. Thus, 
we have four strokes of the piston for each power impulse, and this 
requires two complete revolutions of the crankshaft. 

Two-Stroke-Cycle, or Two-Cycle. In the two-cycle engine, the 
same series of operations is performed in two strokes of the piston, 
or one revolution of the crankshaft; and this is accomplished by the 
use of crankcase compression and the difference in density of hot and 
cold gases. Referring to Fig. 18, it will be noticed that instead of the 
usual poppet valves of the four-cycle engine, the two-cycle engine has 

Fig. 18. Diagrams of Operation of Three-Port Two-Cycle Engine 
Courtesy of "Motor Age", Chicago 

openings in the side of the cylinder, which are known as ports. There 
are two classes of these engines, based upon the number of ports 
employed. The more common is the three-port engine, in which 
the carburetor is connected by a passage to the crankcase, the port 
of this passage being opened and closed by the skirt of the piston. 

Starting with the piston at the lower dead center and traveling 
upward, there will be a partial vacuum produced in the crankcase 
which is air tight. When the skirt of the piston uncovers the inlet 
port, the vacuum will cause a rush of explosive gas into the crankcase 
A, Fig. 18. When the piston has reached the top dead center and 


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started down again, it will shut off this gas passage, and its further 
travel will compress the mixture in the crankcase to a few pounds 
pressure. Near the lower dead center B, the top of the piston will 
uncover the port of the by-pass from the crankcase to the chamber 
above. The gas in the crankcase, being under slight pressure, will 
rush up into the combustion chamber with considerable velocity, and, 
being colder than the spent gases of the preceding explosion, will drive 
these hot gases out through the third port, which w r as uncovered by 
the top of the piston a moment before it uncovered the by-pass. 

Fig. 19. Diagrams of Operation of Two-Port Two-Cycle Engine 
Courtesy of ''Motor Age", Chicago 

In order that the fresh gases shall not pass directly across the 
piston and out through the exhaust port, leaving burned gases in the 
top of the cylinder, the piston is provided with a deflector so as to send 
the cold gases up to the top of the cylinder, driving out the exhaust 
with as little waste of the fresh gases as possible. As the piston 
continues to pass upward, both the by-pass and the exhaust ports 
are closed again and the remainder of the stroke compresses the fresh 
gases. At the end of the compression stroke, that is, just after the 
piston passes upper dead center C, the spark occurs, igniting the 
charge and giving the power impulse to the piston. Thus we have 
inlet, compression, firing, and exhaust taking place in two strokes of 


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the piston, or, in other words, there is a power impulse for every 
revolution of the crankshaft. 

Upon the face of things, one might think that the two-cycle 
engine of equal dimensions and running at the same speed as a four- 
cycle engine would have exactly double the power of the latter. This, 
however, is not so, as the method of getting the gas into and out of the 
cylinder is less efficient in the two-cycle than in the four-cycle design. 

The two-port two-cycle engine varies from the three-port in but 
one particular, and that is that the passage between the crankcase 
and the carburetor is closed by an automatic spring-controlled valve 
instead of by f the opening and closing of a port by the skirt of the 
piston. This is clearly shown in Fig. 19. 


Spring and Frame Construction. 

Seat-Post Springs. The springs used on 
a motorcycle to absorb the road shocks or 
to add to the comfort of the rider are 
usually located on the front forks, in the 

rear frame, or in the seat post. One of Fig ^ Flyi Merkel Spring 
the first firms to adopt a spring-seat Seat Poet 

post was the Harley-Davidson, but the Merkel had used a spring- 
frame construction some time previous. The more prominent of the 
modern spring constructions will be illustrated and discussed. 

The Merkel spring-frame construction is shown in Fig. 20, a 
coil spring being fitted under the saddle and forming a continuation 
of the upper forks. In action, the lower forks are pivoted about the 
crankshaft of the motor below, this acting as a radius for the rear 
axle. The upper forks support the entire weigh c of the motorcycle 
on the coil spring. 

The Harley-Davidson and the Dayton systems, which are very 
similar, are illustrated in Figs. 21 and 22. In these constructions, the 
vertical tube of the frame contains a plunger operated from a fixed 
center with a coil spring on either side. The saddle fastens to a radius 
rod at the top of this plunger, the front end of this radius rod being 
bolted to a clutch on the frame. The entire weight of the rider is 
supported through the saddle on the coil spring below, allowing a very 
easy-riding action. 

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Rear and Front Frame Springs. The Pope uses a leaf-spring 
front fork and a spring type of rear suspension, Fig. 23. The suspen- 
sion consists of a drop-forged bracket on each side, brazed to the rear 
end of the frame, with a tension spring fastened to the top surface of 
the bracket. Double guide rods, as shown in the figure, are used, 
these rods carrying an axle yoke which is free to move between the 
jaws of the bracket, thus allowing the spring to absorb the rear 
vibration. Fig. 24 illustrates the Indian cradle-spring frame at the 
rear. This construction has the lower forks pivoted as on the Merkel, 

Fig. 21. Harley-Davidson Spring Seat Post Fig. 22. Dayton Spring Seat Poet 

but the weight of machine and rider is supported on the two leaf 
springs, as shown. The details of the front-fork leaf springs of the 
Indian are shown in Fig. 25. 

Types of Frames. There are two types of frames ordinarily used 
in motorcycle construction. One is formed with a loop, as shown in 
Fig. 26, the motor fastening to lugs on either side of the loop. This 
construction makes the machine very easy to assemble, and the 
frame is equally strong whether the motor is in or out of the frame. 
The other construction is similar to this, except that the loop below 
is eliminated, as shown very noticeably in Fig. 9. The lugs fasten 


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directly to the crankcase of the motor,' which thus becomes the lower 
member of the frame. 

Motors. Motors for motorcycle use are usually of the four-cycle 
air-cooled variety. These 
motors, as previously 
described, are now built 
with one, two, and four 
cylinders. Water-cooling 
has been tried abroad on 
motorcycles with consid- 
erable success, but so far 
has not been applied in 

Type. We have already 
predicted the disappear- 
ance of the large size sin- 
gle-cylinder engine which 
is still favored by some 
of the public-service cor- 
porations, and, at the 
same time, have pointed 
out the crop of new 
machines of the light- 
weight type which em- 
ploy the one-cylinder 
engine, to say nothing of 
the popular motor-wheel 
type. Some of these light 
singles work upon the 
four-cycle principle, while 
there is also a large crop 
of the two-stroke variety. 
Fig. 27 shows a section of 
the Excelsior light- 
weight two-cycle engine, 
in which one of the points 

worth noting is the de- Fig. 24. Indian Rear Cradle-Spring Rim 

Fig. 23. Pope Rear Frame Spring Arrangement 


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flector built into the piston head for the purpose of causing the fresh 
gases to sweep clear around the dome of the cylinder before reaching the 
exhaust port. It may also be noted that the top piston ring is pinned, 

Fig. 25. Indian Front-Leaf Spring 

Fig. 26. Loop Frame Showing Lugs for Motor Attachment 

as should be the case in all two-cycle engines in order to prevent the 
ends of the rings from working around and becoming snapped off at 
the cylinder ports. The piston is drilled full of large holes in order to 


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assist the lubrication and, at the same time, reduce the weight. This 
is another one of the engines with the outside type of flywheel and with 
the split-bushing-capped connecting-rod end, both similar to auto- 
mobile practice. The valve at the upper left-hand portion of the 
combustion chamber has nothing to do with the two-cycle operation, 
but is merely a relief valve which releases the compression at the time 
of cranking. 

Another single-cylinder type, Fig. 28, is the Smith Motor Wheel 
power plant. This type works on a four-cycle principle. The inlet 
valve above is of the auto- 
matic type, that is, instead of 
being opened mechanically, it 
is opened by the difference 
in pressure during the suc- 
tion stroke. The exhaust 
valve is mechanically opened 
by the usual valve mechan- 
ism. Again, we have the 
outside flywheel and the split 
lower end to the connecting 
rod. In this case, the lubri- 
cation is by splash, and a 
large dipper will be noted 
upon the lower half of the 
connecting-rod cap. The 
construction of the Dayton 
Motor Bicycle engine is the 

Two-Cylinder Type. In r ™* ■*?• Si , ngle ^ y ! ind ! r r M °;°; cycle M f? . 

9 ° r Courtesy of Excelsior Motor Manufacturing and Supply 

the tWO-Cylinder field the Company, Chicago, Illinois 

V-type engines seemed to be supreme in 1915; but again the light- 
weight brothers have disturbed the trend of practice, and the two- 
cylinder four-cycle opposed engine is making as hard a fight for popular 
favor in the light-weight field as the single-cylinder two-cycle. In the 
Indian model, a cross-section of which is shown in Fig. 29, we have 
an example of this construction. It is the same general design 
which English makers have been able to run at 4000 r.p.m. in their 
light-weight machines. The crank throws are set at 180 degrees. In 


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the V-machines the cylinders stand at from 42 to 50 degrees between 
the center lines, depending upon the ideas of the designer. An inter- 
esting feature of the design is to be noted in the placing of the valves at 
an angle in the combustion chamber, making the engine very compact. 
The split connecting-rod bushing and the external flywheel are used. 

Fig. 28. Diagram of Smith Motor-Wheel Power Plant 
Courtesy of A. O. Smith Corporation, MUtoaukee, Wisconsin 

In Fig. 30, we come back to what we have come to think of as 
the highest development of American motorcycle practice, namely, 
the two-cylinder V-type engine. This particular figure shows the 
Harley-Davidson power plant, which is of the L-head cylinder con- 
struction with the inlet valve above the exhaust and operated 
mechanically by a push rod and rocker arm. Other engines of the 


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V-type have the inlet and the exhaust valves side by side in the bot- 
tom of the combustion chamber, while the third school of design places 
both the inlet and the exhaust valves in the top of the cylinder head, 
operating them through rocker arms as just described. 

Instead of an external single flywheel, as we have just described 
in several cases, the V-cylinder engines have enclosed flywheels with 
the crankpin and two crankshafts fitted into them by stout tapers. 

Fig. 29. Section of Indian Twin-Cylinder Opposed Engine 
Courtesy of Hendee Manufacturing Company, Springfield, Massachusetts 

The counterbalances for the inertia forces of the piston are cast as 
part of the flywheels. With the single crankpin and the two rods, 
there are two possible constructions for the lower-end bearings. One 
would be with the rods placed side by side, while the other would 
be the forked rod as shown in Fig. 31. This is the design that has 
become standard practice. Although at first the amateur might 
think that these rods would interfere with each other, the relative 
motion between them is really very slight. 

299 Digitized by GOOgk 



In the highest development of these machines, roller bearings 
are used at the big end of the connecting rods instead of the split 

bushing, which has been 
, referred to in the light- 
weight engine described. 
Great skill is required in 
fitting these bearings, for 
if one roller is larger than 
the other rollers by a very 
small fraction of an inch, 
there will be a binding of 
the bearing upon the 
shaft. When they are 
correctly fitted, however, 
and properly lubricated, 
their life is very long, and 
the friction loss is held at 
a minimum. 

Instead of the cams 
working directly upon the 
ends of tappets to raise 
the valves, it is usual to 
interpose arms, or followers, as 
shown in Fig. 30. Just above 
the cam wheel or the large gear 
is a small rack or portion of a 
gear. This is connected to the 
compression relief and when it 
is desired to relieve the com- 
pression to the motor, this part 
gear is rotated and, through a 
lever connected to it, raises 
both inlet valves slightly off 
their seats so that the compres- 
sion is materially decreased. 
Four-Cylinder Type. Figs. 

32 and 33 illustrate the Hen- 
Fig. 31. Typical Forked Piston Rods for V-Type « • i« i 

Twin-cylinder Engine derson four-cylinder motor- 

Fig. 30. Side View of Harley-Davidson 
Twin-Cylinder Engine 


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cycle. This is also air-cooled and of the L-head type, with overhead 
inlet valves. It is designed f o^ medium-high speed, has a three-bearing 
four-throw crankshaft, three-ring pistons, an enclosed flywheel, and a 
bevel-gear reduction. The motor is lubricated by splash from the oil 
in the base of the crankcase, as will be noted in Fig. 33. This motor 
is particularly neat, noiseless, and flexible. 

European High-Speed Type. Foreigners, with their generous 
experimenting, have gone farther in motorcycle design than have our 

Fig. 32. Rear View of Henderson Four-Cylinder Engine and Transmission 
Courtesy of Henderson Motorcycle Company, Detroit, Michigan 

designers in America. The progress, however, has been in the line of 
experimental work and individual building rather than in workman- 
ship or in accuracy of production, the latter being the American's 
strong specialization. America, in spite of its heavy road conditions, 
is not experimenting with water-cooled motors for motorcycles, 
though England uses them to a limited extent. One of the most 
prominent motorcycle builders in England departs from standard 
practice in adopting both water-cooled and two-cycle principles. 




Consistent performance as a result of these innovations, coupled 
with good workmanship, has given this machine great prominence. 

Fig. 33. Side and End Sections of Henderson Four-Cylinder Motor 

Europe's greatest advantage, however, in motorcycle construc- 
tion has been exemplified by the development of the high-speed 

motorcycle motor. This is ordinarily 
of the horizontal-opposed type, the 
most prominent high-speed low- 
w r eight construction being the 
Douglas, a British machine. This 
motor is able to maintain this high 
speed through a crankshaft balance 
which is practically perfect, allowing 
it to run at the abnormally high speed 
of 4000 r.p.m. for long periods without 
fatigue of material, and hence with 
great efficiency. The motor is of thfe 
L-head type, with air-cooled cylinders 
and an outside flywheel. The cylin- 
ders being placed opposite each other, 
the counterbalanced cranks are set 180 
degrees apart. The entire motorcycle is 
said to weigh under 200 pounds and at- 
tains speeds well above a mile a minute. 
Water cooling is another English experiment, which has proven 
successful. It has not been generally adopted in Europe, however, 
and air cooling has been perfectly satisfactory in this country. 

Fig. 34. 

Excelsior Lubricating 


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Lubrication. Path of OH. A lubricating system, as used on 
the Excelsior motorcycle motor, is shown in Fig. 34, and gives the 
particularly neat method by which motors of 
this type are oiled. In this case, the oil is first 
fed to the main bearing on the cam-case side, as 
shown by the arrow. This oil is fed by pressure 
from a pump and, after covering this bearing, 
is forced out at the end and flows through the 
drill hole shown, which brings it out above by 
centrifugal force to the connecting-rod bearing. 
This bearing throws the excess oil out, splash- 
ing it in all directions and up through the slot 
through which the connecting rod runs. From 
here it runs out on either side and gathers in a 
groove at the bottom edge of the cylinder. The 
bottom of the piston drops into this trough of 
oil every time it comes down, thus carrying the 
even film with it up the walls of the cylinder. 
The excess oil flows down the side of the crank- 
case and feeds the right-hand bearing. Excess p^ 35 Excclaior oil 
from here is caught on the outer end of the Pump 

shaft and returned to the 
crankcase, where it is 
splashed up again into 
the motor for further use. 

In a V-type twin- 
cylinder motor where the 
oil trough at the bottom 
of the cylinder cannot 
catch an even amount on 
account of the cylinder 
angularity, the oil is gen- 
erally allowed to drain 
back at once on the rear 

Cylinder, and, instead Of Fig. 36. Harley-DavidBom Roller-Cam Oil Pump 

going to a main bearing first, it is fed to the forward cylinder. 

Oil Pumps. Fig. 35 shows a type of oil pump which is used to 

feed the oil to the motor. In this construction a small worm drive 

303 Digitized by 



from the cam case or the magneto gear case turns a small crank which 
operates a vertical plunger. This plunger cylinder is so arranged that 
on the top of the stroke oil may flow into the cylinder space, a ball 

check valve holding the 
oil from being sucked into 
the cylinder. On the 
down stroke, the oil inlet 
is covered by the piston, 
and the ball check valve 
opens to allow the plunger 
to force the oil in the cyl- 
inder out of the motor. 
Fig. 36 illustrates a 
special type of pump, in 
which the plunger P is 
operated by a peculiar- 
Fig. 37. Excelsior Starter with Automatic shaped roller Cam H • 
Compression Relief " 

Fig. 38. Indian Kick Starter 
Courttty of Hendee Manufacturing Company, Spring/idd, MaMackutetU 

The shaft of this roller cam contains the elements of a rotary valve, 
with openings at A and D, so that the oil is fed positively through a 
sight feed on its way to the motor. There are no ball check valves in 
this construction, and a screw J enables one to adjust the amount of 


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oil delivered to the motor within very narrow limits. The intake oil 
pipe is shown at S. The oil is fed to the motor through the opening 
G. Since oiling is so important a part of the high-speed motor opera- 
tion, the development of this device has made a change in th^ 
reliability of the modern motorcycle. 

The quality of the oil used is of great importance in the life of a 
motorcycle. Each maker recommends oils suited to his machine, and 
it is well to follow these suggestions. 

Starting. It is hardly probable that the complication of electric 
starting will be adopted widely for motorcycle use, as it is generally 
more trouble to operate a power starter and keep it in repair than to 
use the simple form of kick starter which has become so popular and 
which now is fitted to almost 
all American machines. 

Figs. 37 and 38 show 
forms of starters in use on the 
Excelsior and Indian motor- 
cycles, respectively. The 
main shaft on one side or the 
other is fitted with a small 
gear pinion which is fastened 
to the shaft on a ratchet or 

1x1. smt x F*8- 39. Typical Expanding-Band Brake 

over-running clutch. Ott to Courtesy of Harlev . Davidtum j^^ company, 

~~~ „:^~ :« ~:-,~x^J „ «^«» Milwaukee, Wisconsin 

one side is pivoted a gear 

quadrant fastened to a pedal, which is often of the folding type. 
Pushing down on this pedal with the foot meshes the pinion with the 
quadrant, and a quick thrust or kick of a quarter-turn will then turn 
the motor over several times at fair speed. When the motor starts, 
the small pinion is released, and a strong pull brings the quadrant 
back to its former position, out of mesh with its pinion. The pedal 
is generally fastened in this upward position by means of a clip so 
that it cannot rattle. 

Brakes. A number of types of brake construction are used on 
motorcycles, but they are mostly of the expanding- or contracting- 
band variety. Fig. 39 shows the construction of an expanding-band 
brake. The band is of springy material and covered with a brake- 
lining material. The shoe, or ring, fits inside the brake drum which 
is keyed to the rear-wheel hub. Operation of the lever pushes 


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the ends of the band apart so that it expands forcibly against the 
interior of the drum. 

A similar band may be fitted outside the drum, but in this 
case the fabric will be on the inside of the band, and the lever will 
pull the band tight on the outside of the drum. This is known as the 
contracting-band brake. Fig. 40 shows the brake used on the Excelsior 
motorcycle combining both types, the expanding and contracting 

Fig. 40. Typical Double-Acting Band Brake 

Courtesy of Excelsior Motor Manufacturing and Supply 

Company, Chicago, Illinois 

bands being shown in section with their linings in place. The 
operation is by two levers, shown in the lower part of the illustration. 

Fig. 41 illustrates the pedals fitted to the Henderson motorcycle, 
which operate the brakes of this complete little machine. 

Drive. Belt Drive. The early motorcycles employed belt 
drives of either the V- or the flat-faced types. As the power output 
increased, the belt slippage became excessive and the chain drive 
began to predominate. In the new light-weight machines, however, 
the belt drive has reappeared, especially in the V-type of construction, 


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which consists of a continuous two- or three-ply belt of leather with 
blocks of leather riveted to it, Fig. 42. The blocks are about 1 inch 
thick, and the sides are beveled off at the same angle as the V-pulleys. 

Fig. 41. Henderson Foot Rest and Fig. 42. Peerless V-Belt for Motorcycle Drive 

Brake Pedals Courtety of Peerless V-Belt Company, Cedar Rapids, Iowa 

Shaft Drive. The Pierce Company of Buffalo at one time built a 
shaft-driven four-cylinder motorcycle, but discontinued it after a few 
seasons. The shaft drive is again announced on the Militaire, a 
four-cylinder machine, already shown in Fig. 14. 

Fig. 43. Indian Multiple-Disc Clutch and Three-Speed Gear Set 

Chains. For heavy powers the roller chain seems to have proved 
itself the most efficient. This construction is the outgrowth of bicycle 
practice, and we now usually find two chains, one from the engine to 
the gearset and the other from the gearset back to the rear hub. The 


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chain is made up of a series of rollers turning on hardened pins which 
stand between the side bars. If kept in proper condition, the friction 

loss is very small. 

Clutches. Several kinds of clutches 
are used on motorcycles, the one most used 
being of the multiple dry-disc type, as 
shown at the left end of Fig. 43. This 
consists of a number of thin metallic discs 
faced with fabric brake-lining material and 
keyed alternately to the center shaft and 
the containing drum. When springs are 
allowed to thrust these plates tightly 
together, the amount of friction generated 
makes a reliable drive between the drum 
, and the central shaft. Suitable mech- 

anism is arranged so that, when it is desired 
to disengage the clutch, a lever or pedal 
can release this spring pressure and allow 
the discs to run free without friction 

Pig. 44. Sectional View of Reading- , A ±y 

Standard Cone Clutch between them. 

Fig. 45. Indian Neutral Countershaft 
CourUty of Hondee Manufacturing Company, Spring/Md, Ma$9aehua9Ua 

Metal-to-metal clutches consist of a set of metal discs brought 
into or out of contact by means of a lever. These are generally run 


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in oil to prevent their heating. When the spring pressure is applied, 
it takes a number of revolutions to drive out the oil from between the 
plates and thus prevent a grabbing clutch. 

The Reading-Standard motorcycle, instead of employing a 
countershaft back of the motor, fits an internal-gear countershaft to 
the side of the crankcase and drives from this to the main drive 
sprocket by means of an ordinary automobile-type cone clutch. 
This clutch is shown in Fig. 44. A cone on this clutch is faced with 
leather and operates exactly like an automobile clutch. 

Gearsets, or Change-Speed Mechanisms. Modern motorcycles 
are almost invariably fitted with change-speed gears, which might 
be classed as one-, two-, 
and three-speed types. 

One-Speed. The 
one-speed gear — if it 
can be so called — is 
merely a dog-clutch ar- 
rangement, Fig. 45, used 
to disconnect the motor 
from the rear wheels 
when the clutch is in 
engagement. The cen- 
tral part is a ring which 
can be moved from 
right to left in order to 

fit the notches in its Fig. 46. Dayton Multiple-Disc Clutch* and Sliding- 

« . . , » Gear, Two-Speed Transmission 

face into those on an 

adjacent ring connected to the driving sprocket. The sliding of this 

member is accomplished by means of the small lever. 

Tioo-Speed Planetary. Where but two speeds forward are 
desired, the planetary, or epicyclic, gearset has proven popular. 
This type, which is sometimes called the sun and planet gear, is 
made up of a nest of small gears which usually mesh with an internal 
gear at the same time that they are revolving about a common center 
gear. The small gears not only revolve in space, but also revolve 
upon their own axes. By holding the internal gear in place, a desired 
reduction can be obtained. Such gears were employed upon the 
Harley-Davidson and the Henderson; but, as mentioned before, the 



trend is toward the three-speed sliding-gear transmission, and none of 
the late catalogues of the well-known makers list the planetary gear. 
Two-Speed Gear. Fig. 46 shows a Dayton sliding ring two-speed 
transmission fitted with a multiple-disc clutch, shown in section. 
This clutch is operated by a lever or pedal and, when in engagement, 
enables the sprocket at the left to drive through the gear mechanism 
to the middle, or main drive sprocket. If the small cam ring, shown 
in the center of the gearset, is moved to the left by a lever, the 
dogs engage a shaft from the left sprocket direct to the main sprocket, 
so that one is driving on high gear. On releasing the clutch, the cam 

Fig. 47. Harley-Davjdson Three-Speed Transmission 

ring in the center of the gearset can be shifted to the right to mesh 
with the smaller gear on that side, which is driven by the sprocket at 
the left. This gear now drives through the two lower back gears, back 
through the upper left-hand gear to the main sprocket, which now, 
instead of traveling with the left one, travels at about half its speed. 
This is low-gear position. This type of gearset is used on a number 
of prominent motorcycles, the differences being mainly in details. 
Three-Speed Gear. Fig. 47 shows a three-speed gear fitted to 
the Harley-Davidson, operating on the same principle as the two- 
speed gears just mentioned. At the extreme left is shown the clutch 
and the large and small sprockets. The lower shaft to the gearset is 

310 Digitized by GOQQle 



Fig. 48. 

Method of Mounting Transmission in 
Harley-Davidson Frame 

the main shaft, and the two gears at the right on this lower shaft slide 
on keys on the shaft. The shaft is driven by a big sprocket, while the 
smaller sprocket is fast- 
ened to the left-hand 
gear. If the two sliding 
gears are shifted to the 
left, a dog engages them 
with the left-hand gear, 
these dogs being clearly 
seen in the cut. If the 
gears move to the posi- 
tion shown in the cut, 
the machine is on 
second speed, driving 
through the four gears 
which are in mesh. If 
the two gears are shifted farther to the right, the right-hand one 
of the two lower gears comes in mesh with the right-hand big gear, 
and the machine is on its lowest gear ratio. The method of mount- 
ing this gearset on the Harley- 
Davidson is shown in Fig. 48. 

A smaller three-speed gearset 
used on the Indian motorcycle is 
shown in Fig. 43 in connection 
with the disc clutch attached. In 
this case a single sliding gear on 
the princpial shaft makes all the 
connections and gives a progres- 
sive gearset of extreme simplicity. 
A gearset is a necessity on motor- 
cycles intended for passenger use. 

Electrical Equipment. Devel- 
opment from Battery Current. In 
the earlier days of the motorcycle, 
the electrical current for ignition 
was furnished by dry cells and stepped-up to the required voltage by 
an induction coil. The next development was the almost universal 
equipment with high-tension magnetos, which generated the spark 

Fig. 49. Remy Motorcycle Generator 


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mechanically and erectly furnished high-tension current. With the 
coming of electric lighting and starting equipment on all automobiles, 

the motorcycle enthusiast saw 
the advantage of the electric 
head and tail lights, to say 
nothing of a warning signal, 
and was not slow to demand 
this upon his own type of ma- 
chine. The very nature of dry 
cells works against their con- 
tinual use for supplying head- 
light current, and the storage 
battery has therefore been the 
only solution of the problem. 
A storage battery, however, to 
be carried upon the motorcycle 

Fig. 50. Splitdorf Magneto Generator as Used , , . ... 

on the Indian Motorcycle must be rather Small in Size 

a and thereby limited 

in capacity. 

In the history 
of automobile light- 
ing, the owner soon 
demanded that a 
generator be driven 
by the engine for 
the purpose of 
keeping the storage 
battery in a 
charged condition, 
instead of having to 
take it some place 
f for charging from 
an external source. 

Fig. 51. Parte of Splitdorf Mag-Generator The Same thing fol- 

Courteav of Splitdorf Electric Company, Newark, New Jereey \ owe & ' m the motor- 

cycle field; and we have seen developed a series of generators, Fig. 49, 
driven mechanically by the engine, which are capable of keeping the 
battery floating on the line or of sometimes taking care of the lights. 


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Magneto Generators. These generating machines — the Splitdorf 
type shown in Fig. 50 is used on the Indian — are a unique conception 
and apparently have not been influenced by automobile practice, 
for the instruments usually combine a high-tension magneto and a low- 
tension generator. This combination makes a single-unit machine 
mechanically, but a double-unit machine electrically, there being two 
separate armatures, as shown in Fig. 51, the same field winding 
exciting both fields. In a way, it is wrong to speak of this as partly 
a magneto, because the term magneto implies the use of permanent 
magnets for the production of the mag- 
netic field. The armature, however, is 
of the regular magneto type and delivers 
a high-tension current to the spark plug. 
The generator armature is wound so as 
to deliver about three amperes of cur- 
rent at thirty miles per hour, charging 
a 6-volt battery. The above description 
covers, in general, the Splitdorf system. 

In automobile practice it is very 
common, at present, to use the battery 
or generator current for the ignition; 
and, in order to do this, a transformer 
coil is used to step-up the 6-volt current 
to the extremely high voltage required to 
jump the spark gaps. This coil is very 
often mounted right on the generator. 
The same practice is followed on some 

of the motorcycle systems, one being the C ^S°^ ( 
Midco system used upon the Excelsior, cu-im* Ohu> 

Fig. 52. The ignition current isstepped-up by two small coils which 
are mounted in a protecting case directly above the generator, as 
shown in Fig. 53. In a system of this kind there must be both a 
circuit-breaker and a distributor; these two devices are mounted upon 
the end of the main drive shaft of the machine as shown. 

Automatic Switches. In all electrical systems charging the stor- 
age battery, it is necessary to have an automatic switch between the 
generator and the battery and also some kind of device for regulating 
the output of the generator so that it will not rise to too high a value 

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■f> C 5 ) .t 


eT S 



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at very high speeds of the engine. The first instrument is variously 
known as a cut-in, cut-out, relay, etc., and is merely a device to keep 
the cifcint open as long as the battery voltage is higher than the 
voltage being delivered by the generator. Of course, when the engine 
is at rest, the generator voltage is zero, and it is not until a road speed 
of some 8 to 12 miles per hour is attained that the voltage rises above 
the 6 or 6$ volts of the storage battery. If the circuit was not kept 
open during this period of still engine or of slow running, the battery 
would discharge itself through the generator. These relay cut-in 
switches are usually of the electromagnetic type; and the pull of the 
magnet when the generator is giving out seven volts closes the circuit, 
and the generator begins to charge the storage battery. If the lights 
are on, the generator may take care of the light load and, at high speed, 
charge the battery besides. As 
the engine slows down, our con- 
ditions for wasting the storage- 
battery current through the 
generator appear again, and 
the automatic switch opens 
the circuit. 

Regulation. Roughly 
speaking, the voltage and 
therefore the current, other 
things remaining equal, of a 


Fig. 54. Midco Third-Brush Regulation 

generator increases with the speed of the machine. If the generating 
device is designed to keep the battery in a charged condition at 
reasonable driving speeds, one can imagine the high charging rate 
that would result if there were no regulation of the output, and the 
driver "let her out" for several miles over a fine stretch of country 
concrete. Such a charging rate would probably burn out the winding 
of the generator itself and also cause serious damage to the battery, 
owing to overheating and a resulting buckling and falling to pieces 
of the plates of the battery. One method of regulation is to take 
advantage of the distortion of the field and attach one end of the 
field windings to a third brush, as at A, Fig. 54. This is known as 
the third-brush regulation and as the speed increases, the strength 
of the field automatically decreases, thus counteracting the effect 
that speed ordinarily has upon the current output. In other cases 


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the regulation is accomplished through the throwing in of resistance 
into the field circuit, which is done automatically by means of an 

electromagnetic device very similar to and often combined with the 
relay switch. 


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One- and Two-Wire Systems. There is the same variation in 
practice in the motorcycle field as on the automobile in regard to the 
one- and two-wire systems. The one- 
wire system is also known as the single- or 
grounded-retura system, and the two-wire 
as the ungrounded-circuit system. In 
the grounded-return system but one wire 
is led to each lamp, and the current passes 
back through the fixture and through the 
metal parts of the motorcycle to the 
grounded side of the storage battery. In 
the two-wire system a wire runs both to 

. . i i it i ,i Fig. 56. Splitdorf Ammeter 

and from each bulb, and tpere are two 

contact points in the base of the lamp bulb. Thus, in purchasing 
lamp bulbs, one must examine the old light to see whether it is of 
the single- or the double-contact type. 

It is not advisable to add much more electrical equipment than 
comes with the machine, such as cigar lighters, hand warmers, and 
what not, for these put a load upon the storage battery not calculated 
in the design, which will cause not only unsatisfactory holding of the 
charge but also a possible heating and buckling of the plates, owing to 
excessive discharge. Fig. 55 shows the wiring diagram of the Midco 
system on the Excelsior amd indicates a double headlight of nine 
candle power and four candle 
power and a tail light of two 
candle power. It will be noted 
that the bulbs are marked 7- volt, 
while the Midco is a 6-volt sys- 
tem. Seven- volt lamps are used 
because they give satisfactory 
light and still have a very long 
life. Six or six and one-half volt 
lamps will work perfectly well, 
but will burn somewhat more 

brightly and Will not last as long. "* 67 ' Oombtarfoa Headlight and Horn 

Ammeter. In case one has an electric generator and a storage 
battery upon his machine but no ammeter, it is well to provide such 
an instrument, shown in Fig. 56, as it gives a close check on the condi- 


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tion of the system at all times. The most valuable type is that with a 
zero in the center and a charge scale reading one way and a discharge 
scale reading the other. These instruments are usually wired into the 
system, so that they do not show the actual generator output, but 
rather the output and input of the storage battery. The rider, how- 
ever, soon learns to know whether or not the generator is more than 
able to take care of the lamp load at any certain speed, that is, whether 
it also can charge the battery. One of the valuable features of the 
instrument is that it will show a short-circuit of any account. 

Fuses. Another device in the electrical system is the fuse. 
This is a piece of wire which will melt when a current of greater value 

than is normal for the system is passed 
through it. The wire is carried in a 
small cartridge which slips between the 
clips on the fuse block. 

There is hardly another place where 
space is at a greater premium than upon 
the modern motorcycle; and to assist in 
its conservation a combined headlight 
and horn, shown in Fig. 57, has been 
brought out. 

Storage Batteries. The storage bat- 
tery, Fig. 58, which is such an essential 
part of the new complete electric-lighting 
and ignition equipment, is made up of 
a series of composition lead plates and a 
solution of sulphuric acid known as the 
electrolyte. The plates of two kinds, 
Fig - 58 s Ja y g fB a It^ rcycle positive and negative, are assembled 
^Z^^i^ZTohi^ 1 ^ alternately positive and negative to form 

a cell. Each cell has a potential of a 
little over 2 volts, and there are therefore 3 cells connected in 
series to form a 6-volt storage battery. The capacity of the battery, 
that is, its ampere-discharge rate, is dependent upon the number and 
the size of the plates. Because of the very limited space on the motor- 
cycle, it can be understood that only a battery of small capacity 
can be used. It is, therefore, even more necessary than in automobile 
work to make sure that the generator is charging at its proper rate. 


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When the battery is fully charged, and everything is in good 
condition, the density of the electrolyte should be from 1250 to 1300, 
as read by the hydrometer syringe. As the battery discharges, the 
density decreases and should not be allowed to drop below 1 150. The 
charging and discharging of the battery results in the generation of a 
certain amount of heat, which causes the water in the electrolyte to 
evaporate through the vent plugs. This must be replaced at least 
once a week with distilled water which has not come in contact with a 
metal vessel. Ordinary drinking water or distilled water which 
has been kept in a metal vessel contains enough minerals to cause 
local action within the battery, which greatly shortens its life. The 
Society of Automobile Engineers has formulated a set of rules for 
the proper care of a storage battery. These rules will be found in 
the article on Electric Automobiles, or can be provided by the battery 
manufacturers. They should be carefully read by every storage- 
battery owner. 

Spark Plugs. While on the subject of electrical equipment, it 
may not be out of place to mention the variety of spark-plug stand- 
ards. The majority of motorcycles 
use what is commonly known as the 
metric plug, which means that the fine 
threads on this plug are cut according 
to the metric system. The £-inch pipe- 
thread plug, which is cut upon the 
same taper as the usual pipe standards, 
also is used in motorcycle engines. 
There is still another very common plug 
standard, which does not seem to have 
been taken up by the motorcycle 
makers, but which might be purchased 
easily by mistake. This is the S.A.E. Fig. 59. 
{-inch plug with eighteen threads per 
inch. In the early days of the automobile industry, this same plug, 
which is distinguished by a shoulder and a copper gasket, was known 
as the ALAM plug. Every motorcycle owner should know with 
what type of plug his machine is equipped, so that he will not be 
buying and carrying about with him, for an emergency, plugs which 
would be of no service. 

Simple Passenger Attachment 
for Motorcycles 


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Passenger Attachments. The motorcycle has become so popular 
a vehicle that owners wish to take their friends with them, hence 
has come about the popularity of passenger attachments. Fig. 59 

Fig. 60. Harley-Davidson Side Car 
Courtesy of Harley-Davidson Motor Company, Milwaukee, Wisconsin 

shows the simplest type of passenger attachment for motorcycles. 
This attachment consists of an extra seat that fastens at the back of 

Fig. 61. Harley-Davidson Commercial Van 
Courtesy of Harley-Davidson Motor Company, Milwaukee, Wisconsin 

the driver's seat, which makes a tandem vehicle of the machine. 
Many thousands of these are in use in America. While at first they 
were viewed with a certain degree of contempt by the automobilist, 



they have become accepted as a proper means of conveyance. Many 
motorcycle owners who are not possessors of this attachment fit a 
heavy cushion to the luggage carrier over the rear wheel and mount 
a passenger on this. 

Seeking for more dignity in a passenger attachment, motorcycle 
riders have adopted sidecars, shown in Fig. 60, as a solution. Separate 
upholstered body constructions are fitted with an extra wheel, all of 

Fig. 62. Rear View of FLrible Side Car Showing Truss Frame and Spring Arrangement 
Courtesy of FlzibU Side Car Company, LoudonviUe, Ohio 


which attaches to the side of an ordinary motorcycle so that the 
passenger may be carried in a comfortable conveyance alongside 
the driver. 

The Harley-Davidson Company also manufactures what is 
called a commercial van, Fig. 61. This, it will be noticed, is built 
on the same chassis as the regulation sidecar, Fig. 60, a box taking 
the place of the passenger body. Sidecars are becoming more popular 
every year, as the length of good roads is increasing. Their chief 



disadvantage is the side strain caused by the pull of the third wheel 
Improvements have been made in sidecar construction, as well as 
in all other motorcycle developments, and the design known as the 
Flxible Sidecar, shown in Fig. 62, is intended to relieve much of the 
side strain on the machine when rounding corners. Not only do we 
have sidecars and rear seats for carrying passengers, but there is man- 
ufactured a series of rear cars, which goes so far as to include a lim- 
ousine, Fig. 63. 

The framework for these sidecars, rear cars, etc., furnishes an 
opportunity for all kinds of commercial applications, and besides the 

Fig. 63. Unique Motorcycle Limousine 
Courtesy of Cygnet Rear Car Company, Buffalo, New York 

light delivery in all forms, including the motor wheel, the motorcycle 
chassis has been fitted out to carry machine guns, fire-fighting equij)- 
ment, life-saving apparatus, etc. 

Cripples have also taken advantage of the sidecar and have had 
levers and rods rearranged, until it is possible for them to ride in the 
car and operate the* whole machine therefrom. 

Novelties in Motorcycle Equipment The motorcycle manu- 
facturers have lately made other substantial additions to their 


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equipment. One of these is the three-wheeled motorcycle in which 
seats for two or three passengers are built around the rear axle; but, in 



c .«• 


c . 

£ * 
.3 a 




J. a 


H 3 

the face of the failure of the cyclecar and the light-car type sand the 
consequent reduction of the price of the smaller standard-tread cars 


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to considerably less than $500, this new form of tricycle seems hardly 
justified. Improvements in the styles of package vans also have been 
made. Still another novelty has been put out by the Davis Sewing 
Machine Company, which consists of a three-wheel chassis carrying 
a fully equipped chemical engine, Fig. 64. Such a device has so much 


° § 



a * 



m 2 


more speed than the horse-drawn chemical engine and is so much 
lighter than the combination chemical and steam fire engine that its 
adoption should be a matter of time only. So many fires are put out 
by the aid of a few hand grenades or by the "chemical" that a light 
engine of this type, capable of 30 to 45 miles per hour, would be a 


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distinct advantage. These are useful in suburban districts where 
neither the water supply nor the fire-fighting equipment are always 

This tri-car is well built, the chemical equipment being carried 
on a steel frame running from the front axle to the crankcase. The 
load is carefully balanced, and seats are provided for two men. 

Front Stand. Each year brings out some small device which adds 
to the comfort of the motorcycle rider. Among the latest of these 
small improvements is the front stand, by which the motorcycle can be 
made to stand alone with the front wheel removed, as shown in Fig. 65. 
This will be particularly appreciated when the rider is in the country 
and has to work upon either the front tire or the front wheel itself, as 
that is the time when the soap box support is never available. 


The Motor. When the motor is in good working order, it 
requires practically no attention other than to supply it with fuel and 
keep it properly lubricated. When any serious trouble occurs, a safe 
plan is to take the machine to an expert and have it properly repaired. 
This will usually prove the cheapest way in the end. Some of the 
more common sources of trouble may, however, be located by the use 
of a little common sense and judgment. It is of fundamental impor- 
tance that the motor should be securely attached to its base, as other- 
wise it may be twisted around by the belt or chain, and thus thrown 
out of alignment. It is, therefore, a good plan to go over the motor 
and its connections from time to time, tightening up all loose nuts. 

A very common form of trouble is indicated by a knock, jot 
pound, which will ordinarily be found to be due either to lost motion 
or to premature ignition. The pounding due to lost motion indicates 
too much play between parts which have relative motion and would 
most commonly be caused by looseness of connecting-rod or crank- 
shaft bearings. Premature ignition, on the other hand, causes 
pounding of a sharper and more metallic sound and may be due either 
to overheating or to the fact that the spark is advanced too far. In 
some cases it also may be caused by carbon deposits in the cylinder, 
which become incandescent and in this manner cause premature 
ignition of the gas, A good way to locate a knock is by the sense of 


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sound, which may be assisted by putting one end of a piece of metal, 
such as a heavy wire, against different parts of the motor and holding 
the other end between the teeth. The source of the trouble will then 
be indicated by excessive vibration as the wire approaches it. 

The forming of carbon in the cylinder is objectionable, since it 
causes overheating and loss of power as well as premature ignition. 
This can be avoided by occasionally injecting into the cylinders a 
small quantity of kerosene while the motor is warm, turning the 
engine over a few times, and leaving it thus over night. I n the morning 
the kerosene should be forced out by turning the motor over; the foul 
oil should be drained from the crankcase and replaced with fresh oil. 

The leakage of gases from the cylinder, escaping past the pistons, 
because of wear either in the cylinder or in the piston rings, is likely to 
cause overheating of the upper part of the crankcase. When it is 
found difficult to turn the engine over, the cause is probably the over- 
heating and consequent binding of the piston. 

Valves. In order to obtain the best results from the motor, it 
is important that the valves should be properly seated, and that the 
springs should be neither too stiff nor too weak. It is somewhat com- 
monly supposed that grinding the valves will prove a cure for almost 
any of the ills to which the gasoline motor is heir. This is a mistake, 
and valve grinding should not be resorted to unless it is necessary. 
The grinding of valves is a comparatively simple process, but one that 
should not be carried to excess as it lowers the valve on its seat; 
this produces the same effect as does the lengthening of the valve 
stem, namely, prevents the valve from seating properly, thereby 
causing a difficulty greater than that which the grinding was expected 
to relieve. In order to grind a valve, a paste should be made from 
emery and oil. This should be put both on the seat and on the edge 
of the valve itself. Then the valve should be placed in position and 
turned slowly in its seat by means of a screwdriver, a steady pressure 
being maintained meanwhile; the turning should, for the most part, 
be in one direction but an occasional part-turn backward should be 
taken. During the process, care should be exercised to see that the 
pressure is in a perfectly vertical direction, as otherwise an uneven 
grinding will result. In order to tell when this process has been con- 
tinued long enough and the valve is properly ground, the surface of 
the valve seat and also of the valve may be coated with smoke from a 


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candle; the valve should then be placed carefully in its seat, turned 
completely around once, and examined. If the grinding has been 
properly done, a complete bright ring will be seen all the way around. 
Breaks in this ring indicate that the grinding should be continued. 

Carburetor. The proper action of the carburetor is of vital 
importance to the smooth operation of the motor, and, on this account, 
when anything goes wrong, it is very common for a beginner to 
decide at once that the trouble is in the carburetor and begin 
to tinker with it. As a matter of fact, however, it would be wise for 
the novice not to attempt any adjustment of the carburetor until 
he has made a careful study of the type he is using. 

Ordinarily, the motor should start without priming the carbu- 
retor, unless it has been standing a long time, or unless the weather 
is cold. In case it does not start readily, priming may be resorted to, 
although it should be remembered that over-priming does more 
harm than good, since the motor then becomes supplied with too 
rich a mixture, which is as hard to fire as one which is not rich enough. 
If the gasoline refuses to flow altogether even after priming, the 
trouble can sometimes be relieved by blowing into the opening of 
the <psoline tank. Ordinarily, about the only attention the carbu- 
retor requires is an occasional cleaning, the frequency of which 
depends very largely upon the quality of the fuel used and the care 
with which it is strained. In case the spray nozzle becomes so 
seriously choked that blowing into the tank will not relieve it, the 
difficulty can usually be overcome by holding the finger on the prim- 
ing pin until the carburetor floods, simultaneously racing the motor. 

The adjustment of the carburetor can be determined by observ- 
ing the exhaust. If the mixture is too rich, black smoke and red 
flame will appear. If it is not rich enough, it will be indicated by a 
yellow flame, while normal conditions are indicated by a blue flame. 
An important point to bear in mind is that the proper mixture varies 
with atmospheric conditions and that a richer mixture is required in 
cold or damp weather than when it is hot or dry. 

Ignition. In connection with the ignition system, it is necessary 
to be sure that all connections are clean and firmly made and that 
the insulation is sound throughout. In case of battery ignition 
it is, of course, necessary to see that the batteries are in good con- 
dition. In order to get the best results from the batteries, it is well to 

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have an ammeter with which to test them. New batteries should 
test from 15 to 18 amperes and about 1.5 volts. When a battery has 
run down to 4 or 5 amperes, it can no longer be depended upon and 
should be thrown out. Each cell should be tested separately, and it is 
never well to connect an old cell with new ones, as the old cell tends 
to reduce the life of the new ones. The terminals of a battery should 
never be short-circuited by testing directly across them with a wire or 
screwdriver, as a battery can be completely exhausted in this way in a 
short time. It is well to go over all joints and connections period- 
ically, making a careful examination to see that all binding posts and 
set screws are tight and that all points of electrical contact are bright 
and clean. The insulation also should be examined from time to 
time, looking not only for spots where the insulation has been worn 
away by chafing, but also for any places where it has become satu- 
rated with oil. Inspection of this sort is particularly important in 
the secondary winding, because the insulation in this winding must be 
much more perfect, on account of the high voltage employed, than in 
the low-tension primary wiring. In regard to the contact-breaker, 
it is important to see that it is properly adjusted and that the plati- 
num tip is clean and bright. 

A common cause of trouble in the ignition system is due to soot 
on the points of the spark plug. The spark plug should accordingly 
be removed occasionally and the points fcleaned. 

The magneto is very seldom the cause of trouble and, under 
ordinary conditions, should not be tampered with by an inexperi- 
enced person. One common source of trouble with the magneto, 
which can be easily relieved, is the binding of the carbon brush in its 
holder, thereby preventing proper contact between the brush and 
the commutator. The same thing will, of course, result if the spring 
which holds the brush against the commutator becomes weak or is 

Lubrication. The matter of lubrication has already been men- 
tioned, but it is so vital to the satisfactory operation and to the life 
of a motorcycle that it will bear repetition. The oiling should not 
be a perfunctory operation to be taken care of at random, but should 
be done methodically at intervals depending u-x>n the grade of oil 
used. Of course, it is possible to go to extremes and oil too frequently, 
but too much oil is more preferable than too litl :. 



Only the best grade of oils should be used, as the difference in 
cost is only slight, and a poor oil is sure to cause trouble. The manu- 
facturers are always glad to give advice as to the kind and grade of 
oil best suited to their make of motor, and one would do well to be 
guided by such advice, since no one knows a machine so well as the 
maker, and it is also to his interest that the machine give a good 
account of itself. 

Tires. The principal point to be borne in mind in connection 
with the tires is that they should be kept pumped up hard, as riding 
on soft tires is likely to injure both the casing and the inner tube, as 
well as requiring more power to drive the machine. A tire pump 
should always be carried when on the road, and the condition of the 
tires should be examined frequently for any indication of softness. 

A spare inner tube, sprinkled with tire powder, carefully 
folded, and enclosed in a separate package, should be carried along 
for replacement in case of a puncture or a blow-out. In addition, a 
tire-repair outfit for making quick repairs on the road should always 
form part of the rider's equipment. 

In replacing tires with metal tire tools, care should be taken 
not to chip the enamel off the rim, as this will cause it to rust, and 
the rust will, in turn, injure the tires. On this account, it is well to 
paint the rims occasionally as a guard against rust. Grease and oil 
are very injurious to rubber and should never be allowed to remain 
on the tires, but should be washed off at once with gasoline. 

Control. The speed and the amount of power developed by a 
motorcycle depend upon two factors: the quantity of gas supplied 
to the motor; and the time at which the spark occurs with relation 
to the position of the piston in its travel back and forth in the cylinder. 

The devices for controlling these two factors or for regulating 
the throttle and the spark should be conveniently located so that they 
can be manipulated instantly, while at the same time keeping the 
hands in position upon the handlebars. 

Nearly all the earlier machines were equipped with the twist- 
grip type of control in which twisting one grip varied the position of 
the throttle and the other the position of the spark. This type of 
control has the disadvantage that in heavy going where a firm hold 
on the handlebars is necessary the rider is in danger of twisting one 
or both of the grips unintentionally, thereby varying the position of 

329 Digitized by 



the throttle or spark at the wrong time. This objection is overcome 
to a large extent by having the twist grip located in front of secondary 
grips which are rigidly attached to the handlebars. 

Handlebar, or lever, control is rapidly coming into favor. This 
form of control consists of levers placed in front of the grips with rod 
and knuckle joints or with wire cable leading therefrom to the car- 
buretor and to the spark mechanism. Cable seems to be the more 
satisfactory, for with its use there is no lost motion as is the case with 
the rod and knuckle-joint system. An advantage of the lever type 
of control is that the exact position of the levers can be seen at a 

Whatever the type of control, the rider should so accustom 
himself to its manipulation that he can, in case of emergency, throw 
off the power and apply the brakes instantly. In fact, these opera- 
ti6ns should be so familiar as to become automatic. 

General Instructions. Before starting out, the rider should be 
sure that he has an ample supply of gasoline and oil in the tanks, 
never using anything but strained gasoline. The machine should be 
well oiled and the tires examined to see if they have sufficient air. 
All bolts, nuts, and screws should be gone over, and tightened if 
necessary. The wiring should be examined for loose connections 
or breaks in the insulation, and the batteries should be tested with 
an ammeter. Any excessive slack in belt or chain should be taken 
up. If these matters are attended to systematically before starting 
out, many an awkward and embarrassing delay on the road will be 

The matter of physical comfort while on the road is of impor- 
tance, and in order that the greatest degree of comfort be obtained 
the saddle should be placed fairly low and not too far back. The 
handlebars should be high enough to avoid the necessity of stretching 
or bending forward, and the bars should be so shaped that the hands 
rest upon them in a position which is easy upon the wrists. 

The rider should become so familiar with his machine that he 
can tell by the sound when it is running properly. Any unusual 
noise is a sure indication of something wrong, and the machine should 
be stopped instantly and examined for the cause. It is probable 
that the trouble can be located and repaired in a moment if attended 
to at once; but, if allowed to go on, it might easily develop into soffit 


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thing which would cause serious injury to the machine. The motor 
should not run for long periods of time on the stand and should 
never be allowed to race unnecessarily. 

No definite rules other than those which would be dictated by 
common sense can be given for governing the rider's conduct when 
on the road. A proper consideration for the rights of other vehicles, 
and particularly for pedestrians, should be observed, and one must, of 
course, take into consideration the rules in regard to speed limit which 
obtain in the particular locality through which he is driving. The 
machine should be kept under control at all times, so that it can be 
brought to a stop almost instantly in case of any sudden obstruction in 
the traffic. Also it is well not to drive too close to the vehicle ahead, 
as this may stop suddenly, while the one behind you may not stop, 
thus causing an awkward, if not serious, situation. In turning corners 
or in passing other vehicles, a wide curve should always be taken in 
order to avoid the tendency to skid, which arises from taking sharp 
turns at high speed. Always slow up when turning a corner. 

One of the principal causes which has brought the motorcycle 
into disrepute is the excessive noise caused by riders opening the 
muffler cut-out unnecessarily. There are times when it is necessary 
to do this, but the Use of the cut-out should never be carried to excess. 

When starting on a trip which will keep the rider out after dark, 
the lighting system should be examined to see that it is in good con- 
dition, as it is required that the motorcyclist show a headlight and a 
tail light at all times after dusk sets in. 

Upon returning from a ride, the motorcycle should always be 
cleaned before putting it away or at least as soon as possible there- 
after. The longer the cleaning process is delayed, the more difficult 
an operation does it become. Mud which is allowed to cake upon the 
cooling flanges of the motor cuts off the circulation of the air and 
causes overheating. Oil running down from the bearings collects 
dirt, which is sure to work back into the bearings sooner or later and 
cause trouble, while the presence of mud and moisture on the machine 
causes rust, which soon injures the appearance of the machine, 
if it does not do more serious harm. In fact, cleanliness at all times 
and in connection with all parts of the machine is a golden rule of 
motorcycling, and is an investment of time which will give large 
returns in the satisfactory operation and life of the machine. 


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. Carburetors. Probably the greatest number of calls made upon 
the motorcycle repair man are for the readjustment of the carburetor. 
This is often simply a matter of ordinary adjustment, but where the 
owner finds himself unable to get a satisfactory adjustment, although 
he has been able to do so in the past, it is usually because of some fault 
in the carburetor or in its control mechanism. A common source of 
trouble is the sticking of the auxiliary air valve, which the repair man 
may often cure by a drop of oil on the shaft. 

In the types of carburetors where the amount of opening of the 

throttle valve controls 
some other function, as 
the lift of the needle 
valve, a great deal of 
trouble will be experi- 
enced by wear and subse- 
quent play of the shaft 
and connections carrying 
the throttle valve. The 
action will be very 
erratic, depending upon 
which way the play hap- 
pens to be when the 
throttle is being closed 
or opened; in fact, the 
engine may even speed 
up during the closing 
operation. The repair 
for this is usually a small bushing to bring the shaft back to firm 

When flooding of the carburetor is not caused by dirt under the 
float valve, it is usually a matter of a fuel-soaked float. These floats 
are generally made of cork, and the cure is to dry them out and recoat 
with yellow shellac. When the floats are made of metal, tiny pin 
holes, or porous places, in the soldering sometimes develop, which 
allow gasoline to enter and causes flooding. To discover the place 
of the leak, the float should be submerged in very hot water, which will 

Fig. 66. 

Tarn Showing Bad Results from Using 
Lfter with Too Great Pressure 


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cause the gasoline to vaporize and bubble through the leaking portion. 
After this has been marked, a fair size hole should be punched in the 
top of the float, through which the entrapped gasoline may be drained 
out. The portion showing the leaks should then be soldered, and, 
after the float has cooled down, the hole in the top should be closed 
with solder. If this top hole is closed before the leaks are soldered, 
the heat of soldering will cause a partial vacuum inside the float, 
resulting in a seepage of gasoline through a seemingly tight float. 

Valve Troubles. A great many times the carburetor and car- 
buretor adjustment will be blamed by the owner when the trouble is 
from some other source. For instance, the back-firing, which is the 
usual indication of a lean mixture, may be caused by poorly seating 
inlet valves. On the other hand, the galloping of the engine, which 
is usually the symptom of too rich a mixture, may be due to leaking or 
sticking exhaust valves. On the modern machines one of the causes 
for faulty valve spring and valve action is very often the accumulation 
of dirt inside the sleeves which cover the valve mechanism. The 
cure, of course, in this case, is a thorough cleaning. The cure for 
leaking valves is a matter of grinding in. 

Removing Valves. In the removal of valves the use of valve 
lifters has become very common, and their operation is so simple that 
little need be said concerning them. However, there is one warning 
which is worth while, particularly when using a type of lifter with 
which the operator is not familiar, and that is, that he does not catch 
the spring retaining-pin in the lower part of the lifter at the same time 
that pressure is being exerted upon the top of the valve, Fig. 66. The 
result in such a case would be a bent valve stem, which is very hard 
to remove. 

Air Leaks in Inlet Manifold. Irregular running may be caused 
by air leaks at the joints of the inlet manifold. The repair man's 
test for this is to take the priming gun in the gasoline tank and squirt 
a good quantity of fuel around all the joints. If these joints leak, 
the engine will die from an over-rich mixture. The same galloping 
effect that was noted from the poorly seating exhaust valve also may 
be caused by weak exhaust-valve springs. 

When an engine is cold, a certain amount of clearance must be 
left between the top of the tappet and the valve stem. This is in 
order that the valve may expand upon heating up and still not ride 


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upon the tappet, which would cause a poor seating of the valve. So 
far as wear upon the cam and upon the valve mechanism is concerned, 
it is fortunate that the motorcycle rider is not the fiend for silence that 
his cousin, the automobilist, has become. For this reason, the valves 
are set with plenty of clearance, .008 of an inch being good practice. 
In some cases the design is such that the cylinder actually lengthens 
more than the valve, owing to the heat of running. In such a case the 
tappet clearance would be increased instead of decreased upon 
warming up, and the noise would probably be excessive. Such 
engines, of course, may be adjusted much closer than the figure above 

Fig. 67. Handling Tappet Nuto with Two Wrenches 
Courtesy of Hendee Manufacturing Company, Springfield, Massachusetts 

given. Both the owner and the repair man should have a set of 
feelers and also two wrenches of the size of the tappet nuts, Fig. 67, 
so they need not be forced to use a bicycle wrench for making these 
adjustments. With air-cooled motors, it is surprising how often the 
tappet clearances have to be checked up for good results. 

Overhauling. Where an overhauling job is on hand, the first 
thing, of course, is the stripping of all connections between the engine 
and the frame of the machine. In the repair shop, it is usually 
handiest to do all the overhauling work on the bench; therefore the 
whole engine is at once removed from the frame. 


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Valves. The scraping of carbon and the grinding of valves go, as 
a matter of course, with every overhauling job; and, where the major- 
ity of the work is with one make of machine, considerable time may be 
saved in grinding in the valves by having a dummy valve seat. It 
has been found, particularly in the case of badly-pitted exhaust valves, 
that it takes a much longer time to obtain a satisfactory surface on 
the valve itself than it takes on the cylinder seat, and, therefore, this 
dummy will save the unnecessary cutting down of the motor casting. 
The dummy may be made of cast iron, from a special pattern, or it 
may be a portion of an old damaged cylinder. Another thing used by 
one of the large motor-car companies, and justifiable only where a 
great many machines of the same make are worked upon, is to have 
made up a special seating reamer that will give a convex surface rather 
than a flat conical one to the seat in the cylinder. The advantage 
claimed for this is, that it takes less grinding to obtain a gas-tight 
joint, and that the pounding action of the valve tends constantly to 
widen the seat. Some valves are designed with a flat instead of 
conical seat, but the grinding process is the same. 

Piston Pins. Whenever the engine is down, the repair man 
should not fail to look at the fastening of the piston pin to see whether 
there is any trouble in that direction. A piston pin which comes loose 
and works sideways will act exactly like the tool in a shaper, cutting a 
broad groove down the side of the cylinder. As a general rule, the 
piston-pin bearings are bronzed bushings, and, although wear at this 
point is not commonly excessive, poor lubrication or very great 
mileage will produce play. This causes a knock which is very often 
mistaken for a piston slap. The remedy, of course, is a new bushing 
or, very possibly, both a bushing and a pin. 

Big-End Piston Bearings. At the lower end of the rod, the big- 
end bearings in the large twin machines are usually of the roller type, 
and when these give trouble, new sets of rollers have to be fitted. In 
case it is simply a matter of wear from long service, slightly oversized 
rollers are used. This particular job is one requiring unusual care and 
skill, and the repair man should be absolutely certain that the rod can 
be spun on the shaft for any length of time without the rollers climbing 
or jamming owing to the presence of some of slightly different size. 
In some of the older machines, bronze bushings were used for the big- 
end bearings and these, of course, are much more easily renewed. 




Gaskets and Washers. It has been found that it does not pay to 
try to use any of the old gaskets in putting the job back together, as 


Fig. 68. Set of Centers Made up for Handling Crankshafts 

they are almost sure to leak. New felt washers at the crankcase 
should also be used, even though the old ones seem in pretty fair 

Fig. 69. Method of Marking Timing Gears 
Courtesy of Hendee Manufacturing Company, Springfield, MaBaachuutU 

shape, for, before another overhauling, it is more than likely that the 
old ones will begin to leak oil. 

Truing up Crankshafts. When the built-up type of crankshaft 
and the double flywheel have been torn down, for the fitting of new 


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bearings or for some other purpose, it is practically sure to be out of 
true when reassembled. In some cases, a line is marked upon the 
surface of both flywheels, and the truing is done by placing the crank- 
shaft ends on blocks and striking with a soft hammer until a steel 
straightedge may be laid across the flywheels so as to exactly coincide 
with the two lines and show no light underneath on the flywheel 
surfaces. An even better way of truing the assembly is to have made 
up a set of centers, similar to Fig. 68, and, by the use of a machinist's 
gauge discover where the crankshaft is out of true. It is then 
straightened by the hammer method. In the first case, it is really the 
flywheels that are being trued, 
while in the second case, it is the 
more important shaft itself. Before 
the truing operation, the nuts may 
be drawn up good and snug; but, 
after the truing is done, it is found 
that they can be drawn still tighter. 
Valve Timing. Marking Gears. 
In a complete overhauling job, it is 
more than likely that the timing 
gears have been removed for clean- 
ing and inspection, in which case 
the engine has to be re-timed 
upon assembling. It is usual for 
the manufacturer to place marks, 
in the form of little cuts or prick- 
punch centers, on the gears, Fig. 69, 
so that they may be replaced in the 
proper manner. One method is to 
prick-punch each set of teeth while 
under some certain conditions, such as at the point of closing of the 
exhaust valve. Another method is to line up certain marked teeth 
with marks made in the back wall of the gear case. It sometimes 
happens that the manufacturer's marks are not found, and a new set 
of marks is put on by the repair man before disassembling the job. 
At a later date, both sets of marks may show up, with a resulting con- 
fusion. It is well, then, to know something of the valve timing, 
instead of having to depend blindly upon the marking of the gears. 

Fig. 70. Method of Following Out Valve 
Timing by Means of Scale 


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Opening of Valves Not on Dead Center. In the discussion of the 
principle of operation of a four-cycle engine, one would be led to 
believe that the inlet valve opened exactly on upper dead center and 
closed on lower dead center, while the exhaust valve had an opposite 
performance. This is theoretically true; but practice has shown that, 
owing to the inertia of the flow of gases and other little-known con- 
ditions within the engine, the valve timing can be changed consider- 
ably from the dead center points, giving marked improvement in 
the power output of the engine. 

Marking Flywheels — Automobile Practice. In automobile prac- 
tice, it is customary to speak of valve timing in degrees on the crank- 
shaft circle, and the openings and closing of the valves are usually 
laid off and marked upon the rim of the flywheel. Since in most of 
the motorcycles the flywheels are enclosed, this method is not em- 
ployed, and where the maker furnishes information as to the valve 
timing, it is in terms of the travel of the piston from the upper or 
from the lower dead center, as measured in inches. 

Getting Valve Timing with Scale. Where the cams are all made 
integral, only one point of the timing can be controlled, the other 
points being in a fixed relation, the accuracy of which depends upon 
the workmanship in the cam-grinding department. Since the closing 
of the exhaust and the opening of the inlet is important for smooth 
running, this is the point that is taken for setting the valves. Fig. 70 
shows a very easy method of following out the valve timing. A scale 
is dropped through one of the openings in the top of the cylinder, 
possibly the spark-plug hole, and, after the dead-center points have 
been noted, the crankshaft is revolved until the scale shows that the 
piston has moved down or up the desired distance from dead center. 
With the crank at this point, the gears are slipped into mesh so 
ihat the valve will be just opening or closing, as the case may be. 

In some cases, the inlet and exhaust valves can be timed sep- 
arately. Owing to the inaccuracies in grinding, one seldom can obtain 
both the opening and the closing points stated by the manufacturer. 
It is best, therefore, to set the timing on the closing of the exhaust and 
the opening of the inlet, letting the opening and closing, respectively, 
take care of themselves. 

The following timing instructions are taken from the instruction 
book of a well-known maker and are illustrative of the form: 


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Twin-Cylinder Motor 
The exhaust valve "should open when the piston is f inch to 1 inch before 
bottom center and should close A inch to ^ inch after top center. The inlet valve 
should open -fa inch to A iuch before top center and close i inch to } inch after 
bottom center. With advanced spark, the motor should fire J. inch to A m ch 
before dead center. Time each cylinder separately as the interrupter housing 
steel segments are often out of line 

Single-Cylinder Motor 

The exhaust valve should open f inch to } inch before bottom center and 
close A inch to A mcn after top center. The inlet valve should open on dead center 
and close } inch to | inch after bottom center. The spark timing is the same as 
that of the twin. 

Oily Clutches. The dry 

clutches with alternate discs 
covered with a woven fabric of 
asbestos and brass or with copper 
wire give considerable trouble 
from slipping, owing to the 
presence of grease or to the glaz- 
ing of the surfaces. When grease 
is the cause, the clutch is disa- 
ssembled and washed in gasoline. 
One shop takes the plates and 
piles them in pairs and then sets 
fire to pieces of oil-soaked waste, 
shown in Fig. 71, in order to com- 
pletely burn out all the grease. 
The surface is then roughened 

.- i A i j Fig. 71. Burning Oil Off Clutch Discs 1 

up with coarse emery cloth and 

chalked, after which the clutch is again assembled. The chalk is for 
the purpose of soaking up the grease and of giving a fairly harsh engage- 
ment. In case the trick has been overdone, a little engine lubricating 
oil squirted into the clutch will make the engagement easy again. 
The most clutch trouble has come when a side car has been 
added; and in one case the makers provided for this by so designing 
the clutch that the usual equipment of eight springs could be increased 
by eight when a sidecar or a delivery van was attached to the machine. 
This makes the clutch action suitable under all kinds of service. 
Most motorcycle clutches, whether of the cone or of the disc type, 


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have more than one clutch spring — usually three or five. It is of very 
great importance, therefore, in adjusting one of these clutches, to give 
the nuts on each spring exactly the same number of turns, otherwise 
the action will be very unsatisfactory and the clutch liable to serious 
damage. On some of the older cars with belt drive, the clutch has 
been accused of slipping, when, in truth, the trouble was with the 
belt. This resulted in continued adjustment Qf the clutch, until the 
load upon the thrust bearing was so great that it went to pieces. 


niGhfT WW. 


Fig. 72. Method of Sanding-In Brushes 
Courtesy of Auto Electric Systems Publishing Company, Dayton, Ohio 

Cleaning Chains. A roller chain and set of sprockets is a highly 
efficient transmission unit when kept in good condition, but not 
otherwise. One or more times during a season, depending upon the 
mileage, the chains should be removed, cleaned well in gasoline or 
kerosene, and then let soak over night in oil. The next day, they 
should be hung up to drip until they are dry. There is no use trying 
to hurry the oiling process, as the object is to let the lubricant work 
into the small bearings between each pin and roller. 


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Although chains and sprockets are laid out by the designers, 
with such a number of teeth that the one particular link of the chain 
will be a long time reaching a particular tooth for a second time, it 
does sometimes happen that the wear is not evenly distributed. In 
such a case, a chain which was satisfactorily quiet and apparently 
having considerable service left in it will be found noisy, or will bind 
when replaced after the overhauling. Before their removal, there- 
fore, it is not unwise to mark, in some way, the position of the chains 
and to return them to the same location after the cleaning process. 

f%ca mumt bm cut 
cJmpn bmtvmmn 

(jOP nico mumt not bm Imft ~cth 

thin mafmrn rmtt to jyini<i 

Fig. 73. Method of Undercutting Mica Insulation on Commutator 
Courtesy of Auto Electric Systems Publishing Company, Dayton, Ohio 

Dirty Muffler. There is one unit of the machine which the care- 
less repair man or the amateur may neglect to go over in the over- 
hauling job, and that is the muffler. This is a grave mistake, for an 
air-cooled motor naturally burns a good deal of cylinder oil; and it 
will be found that after a season's running the muffler will be pretty 
well choked up with carbon. With an engine which has been burning 
an excessive amount of oil, there may even be an accumulation of 
carbon and oil in the muffler, which will be of the consistency of wet 
cement. These conditions produce a back pressure upon the engine, 
which cuts down the power no matter in what mechanical condition 
the engine may be. It is the allowing of dirty mufflers that probably 
causes so many riders to annoy the public with the use of the muffler 
cut-out. If the muffler is clean and clear, there is really no excuse for 


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the cut-out except in testing for engine operation, for, under these 
conditions, the difference in power attained is almost negligible. 

Electrical Troubles. Electrical troubles may be classified under 
two heads: short-circuits and open circuits. In the first case, there is 
a path back to the generator or storage battery before the current has 
reached the desired point. This is usually due to chafed installation 
or to a loose strand of wire. The open circuit means a break in the 
path of the current and often occurs at the point where the wire enters 
the connection to a lamp, a horn, etc. 

Short-Circuits and Open Circuits. A serious short-circuit will 
blow the fuse, and there is no object in replacing it with a new fuse 
until the point of trouble has been found, as the new fuse will, in turn, 
be blown out. A trouble lamp may be inserted in the fuse block, as 
shown in the Excelsior diagram, Fig. 55, and as soon as the difficulty 
is found, the lamp will go out. The open circuit is usually easier to 
trace, as the lamp or the horn in that circuit will fail to work, while 
the rest of the system will be in good order. 

Lubrication of Electrical Equipment Requires Care. Over-lubri- 
cation of a generator is a serious matter, for if oil works its way into 
the windings, it is liable to soften the installation and also to cause other 
damage. On the other hand, all bearings must be lubricated, particu- 
larly those running at the high speed that armature bearings do. 

Care of Brushes. In time, the brushes may need dressing and 
the armature brightening up. Fine sandpaper can be used for this 
purpose, as shown in Fig. 72. Emery cloth should never be used on 
the brushes or the armature of a generator, as emery is a conductor of 
electricity, and if it becomes embedded between the commutator 
segments, it will cause a short-circuit in the armature. After long 
service, the mica installation between the commutator bars may need 
dressing down, and the method of doing this is shown in Fig. 73. 

Storage Batteries. So far, the demand for storage-battery work 
on motorcycles has not become extensive enough for many motor- 
cycle repair shops to put in a battery charging and overhauling 
department. Many shops will probably do so soon, as the number of 
electrically equipped machines keeps increasing and small-capacity 
charging sets are being developed. At present, the regular battery 
service stations are best equipped to handle all major battery work. 


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CD* ® 

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Development of Steam Engines. That steam could be employed 
to produce mechanical motion was first noted in history about 130 
B. C, but it was not until the seventeenth century that it found 
practical application in the industries. The developments were com- 
paratively slow, however, until James Watt (1769) developed his 
engines to a point where they employed practically all the principles 
of the modern double-acting, condensing steam engine. 

•With these rapid inprovements came the idea of using the steam 
engine as a means of road locomotion, and in the opening years of the 

Fig. 1. Early Steam Carriage Built by Cugnot (France) in 1770 

nineteenth century such machines were actually built and known as 
"road locomotives", Fig. 1. These machines might be called the 
forerunners of the steam automobile, although structurally they 
more nearly resembled the later traction engines. Bad roads, great 
weight, public opinion, and the development of railroads caused road 
locomotives to drop out of sight until the real coming of the automo- 
bile almost a hundred years later. 

In the meantime the steam engine — both stationary and loco- 
motive types — had reached a high state of development and hence 
many of the early automobiles carried this type of power plant. 


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Later improvements were made and are still being made along lines 
peculiar to steam automobile construction. Although during the 
last few years the steam car has not kept pace in numbers with 
other types of automobiles, it has certain characteristics, such as 
strong pulling powers at low speeds, capacity for big overloads, and 
ease in driving on the road, which make it especially useful under 
some conditions, the success of the London steam omnibuses being a 
good example. 


In the modern steam automobile the power plant is made up of 
the same general units as make up the stationary power plant, the 
only difference being the extreme compactness necessary and the 
development of the great flexibility required to meet the sudden 
changes in load conditions. With both plants there must be a supply 
of fuel, a means of burning it, a boiler or steam generator, a supply of 
water, an engine, and various means of controlling the amounts of 
fuel, water, and steam. 

Location of Engine* With steam automobiles there is no uni- 
formity of practice as to the placing of the different units in the 

Fig. 2. Plan View of Stanley Steam-Car Chassis 
Courtesy of Stanley Motor Carriage Company, Newton, Massachusetts 

running gear or chassis. For instance in the Stanley, Fig. 2, the 
boiler is under a hood in front of the driver and the engine is geared 
directly to the rear axle. In the case of the White cars, which 
were built in comparatively large quantities from 1904 to 1910, the 
engine was placed under the hood in front with a shaft running back 
to the rear axle. In the White car, a set of gears was also used in the 


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drive, by which the relation of engine to wheel speed could be reduced 
to one-half the usual amount, thus doubling the driving effort, or 
"torque". The White boiler was under the front seat. The new 
Doble, Figs. 3 and 4, uses the general arrangement of the Stanley. In 



* ? 


the Leyland steam truck, Fig. 5, and the National busses, both of 
England, the boilers are in front, the engines are under the floor 
boards, with a countershaft and final chain drive, as in Fig. 5, or a 
shaft drive direct to the rear axle. 



Boiler and Engine Types. Almost equal variation is found in 
the types of boilers and engines. The difference between fire-tube, 

Fig. 4. Side View of Doble Steam-Car Chassis 
Courtesy of General Engineering Company, Detroit, Michigan 

watei -1 ube, and flash generators is taken up in the section devoted to 
boilers, while the engine types are taken up in their respective section. 

Fig. 5. Leyland Steam Truck with Chain Drive to Rear Wheels 
Courtesy of Leyland Motor* Company, Ltd., England 

Some of the cars use the water over several times by condensing the 
steam in coolers, or "condensers", placed at the front of the car. The 


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White and Lane did this, and it is now done by the Stanley, Doble, 
and most of the English steam cars and trucks. The Stanley, up to 
1915, had no condensers, allowing the steam to escape into the air 
after it had passed through the feed-water heater. 

Simplicity of Control. As a general rule, the steam cars do not 
employ a transmission for giving various forward-gear ratios and 
a reverse. The extra heavy loads, as in starting, are taken care of 
by lengthening the cut-off and by "simpling", terms which will be 
more fully explained later. Instead of running the engine always in 
one direction and using a gearset for reversing the car, as is done on 
gasoline automobiles, the engine is itself reversed by means of chang- 
ing the timing of the valves through the aid of the valve gear, or 

This change of the valve-timing is used only at starting, reversing, 
or under very heavy load conditions, all ordinary running being 
accomplished with the cut-off in one position. The control of the 
speed of the car, therefore, is accomplished under normal conditions 
by changing the amount of steam going to the engine. The steam is 
turned on or shut off by a hand-operated valve, known as the "throttle 
valve", and this valve is turned by a lever, or second small wheel, 
just above or below the steering wheel. Thus the actual driving of a 
steam car consists of steering and operating the throttle. There are, 
however, numerous gages, valves, etc., which have to be worked upon 
when firing up, and which have to be given occasional attention on 
the road; these will be considered in detail in the following pages. 

Having treated in a general way the different types of steam cars 
and their parts, the theory underlying the behavior of steam will be 
touched upon before taking up the details of construction and the 
operation of the various units, 


All forms of energy, such as light, sound, electricity, and heat, 
are believed to be different forms of vibration either of the molecules 
of material substances or of the ether which is believed to pervade 
all space. 

Energy is indestructible, but any form of energy may be con- 
verted into $ny other form. Steam engines are classed as heat 



engines since they are employed to transform heat energy into me- 
chanical work. Heat may be transmitted from one body to another 
in three ways, namely, by radiation and absorption, by conduction, 
and by convection. 

Radiation and Absorption. Radiation is the transfer of heat 
from one body to another body not in contact with it. It takes place 
equally well in air or in vacuo. The rate of heat transferred depends 
partly on the distance separating the two bodies, and partly on the 
nature of their surfaces. In general, light-colored and polished 
metal surfaces radiate heat more slowly than rough and dark-colored 
surfaces. The laws governing absorption are the same as those 
governing radiation. 

Conduction. Conduction is the transfer of heat through the 
substance of a body — solid or liquid — to other portions of the same 
body, or to another body in physical contact therewith. Metals are 
the best conductors of heat, but some metals, such as copper, are 
better conductors than others. Other solids, such as stone, wood, etc. , 
rank after the metals. Liquids are very poor, and gases still poorer, 
conductors of heat. A vacuum is perfectly non-conducting, though 
radiation may still take place through it. 

Convection. Convection is the term applied to the absorption 
of heat by moving liquids or gases in contact with heated surfaces. 
If a blast of air be directed on a piece of hot iron, the iron cools far 
more rapidly than it would in still air. The reason is that, as the air 
is a poor conductor, its molecules do not transmit heat readily from one 
to the next, but if each molecule on becoming heated is immediately 
replaced, heat is rapidly transferred. This property of air of taking 
up heat rapidly when blown over a hot surface is employed in 
gasoline automobiles to cool the so-called "radiators". In reality, the 
heat radiated cuts a small figure compared with that dispersed by 

What has just been said regarding air is equally true of other 
gases. It is also true of most liquids. 

Relative Conductivity. Heat conducting qualities vary for 
different substances. Silver, copper, and aluminum conduct heat 
very rapidly, while asbestos is a poor heat conductor and is therefore 
used around the outside of automobile boilers. 

Expansion. Another heat property which has to be con- 


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sidered in the selection of material for steam cars is that of expansion. 
Some metals expand much more than others for each degree of rise 
in temperature. Since brass and copper both expand under heat 
much more than iron they are used in preference to iron in the con- 
struction of expansion tubes, which are fully described later. 

Temperature Measurement Scales. Temperature, which is the 
measure of the intensity of heat, is expressed by means of divisions 
called degrees on some thermometer scales. The 
two thermometers in most general use are the 
Fahrenheit and Centigrade; the former being the 
more common in America and England for both 
engineering and household use, while the latter 
is used exclusively on the Continent. 

Freezing of water occurs at 32° F. (Fahren- 
heit) and boiling of water at 212° F. The scale 
between these two points is divided into 180 equal 
parts. On the Centigrade scale, the points of 
freezing and boiling occur, respectively, at 0° C. 
and 100° C, and there are, therefore, 100 equal 
divisions between the two points, Fig. 6. Thus 
it is seen that every 5 degrees Centigrade equal 9 
degrees Fahrenheit. 

Conversion of Scales. To convert readings in 
one scale to readings in the other, the reading 
given is substituted in the following equation: 



Fig. 6. Centigrade and 
Fahrenheit Thermome- 

ters, Showing Com- 

Thus, if a temperature is given as —5° C. it is 
equal to 23° F.; 23° C. equals 73.4° F. Conver- 
sion tables over large ranges are given in engineering handbooks, 
such as Kent. 

Absolute Zero. In engineering calculations the absolute zero and 
the absolute scale are sometimes spoken of. This absolute zero, which 
will be mentioned again, is taken as -270° on the Centigrade scale 
and -460.6° on the Fahrenheit scale. Thus -5° C. equals +265° on 
the C.-absolute scale and +483.6° on the F.-aboslute scale. 


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Almost all substances expand with rise of temperature. Solids 
expand least, and in some the expansion is imperceptible. Liquids 
expand about as much as solids, sometimes slightly more. Gases 
and vapors expand a great deal if free to do so. 

Boyle's Law. Before considering the expansion of gases under 
changes in temperature, let us see how they act when the temperature 
is unchanged. A gas is perfectly elastic, that is, if not confined in any 
way it would expand indefinitely. The attraction of gravity is all that 
prevents the atmosphere surrounding the globe from dispersing into 
infinite space. When air is partly exhausted from a closed vessel, 
the remainder, no matter how small, expands so as to distribute itself 
equally throughout the vessel. 

If a cubic foot of air at atmospheric pressure be compressed 
into one-half cubic foot without change in temperature, its pressure 
will be precisely twice what it was before. In speaking of gas pres- 
sures in this manner, it is customary to deal with absolute pressures, 
that is, pressures above a perfect vacuum. Thus atmospheric pressure 
at sea level is approximately 14.7 pounds per square inch, and a cubic 
foot of air reduced one-half in volume will have an absolute pressure 
of 29.4 pounds. 

This relation of pressure and volume is expressed in "Boyle's 
Law", which states that, so long as the temperature is unchanged, 
the product of the pressure and volume of a given weight of gas is 
constant. That is 

PV = C 

This is the most important of all the laws of gases. 

, Curve Expressing Boyle's Law Relation. Fig. 7 expresses the 
relation between volume and pressure of a given weight of air starting 
at atmospheric pressure and compressed to a pressure of 500 pounds 
without change in temperature; also expanded to a pressure of 
one pound absolute. Horizontal distances represent volumes, the 
volume at atmospheric pressure being unity; and vertical distances 
represent absolute pressures. To find the pressure of the air for any 
volume greater or less than one, locate the given volume on the 
base line, then, from this point, read up to the curve and find the 
desired pressure by moving horizontally from the curve to the 
scale at the left. 


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Behavior of Oases with Changes of Temperature. As heat is a 
mode of motion, it follows that when all heat is withdrawn motion 
ceases, and the molecules, even of a gas, become fixed. From experi- 
ments and thqpreticai considerations the absolute zero, representing 
the absence of all heat, is believed to be —273° C, or approximately 
-460°F. In most theo- 
retical studies of the 
behavior of gases, tem- 
peratures are reckoned 
from absolute zero in- 
stead of from the arbi- 
trary zeroes of the con- 
ventional thermometer. 

When a gas of given 
weight at an absolute 
temperature of 273 de- 
grees — that is, 0° C. on 
the customary scale — is 
raised intemperature one 
degree without change 
in pressure, its volume 
is increased *4t- A sec- 
ond degree of added tem- v 9IV mw 

perature increases its Vol- Fi *. 7 « Curve Showing Relation between Vohxme 

* and Pressure of Air 

ume the same amount, 

and so on. In other words, for each degree Centigrade of added tem- 
perature its volume is increased *t* of its volume at 273° A. 

If degrees Fahrenheit are taken instead of Centigrade, the 
expansion is y? j of the volume at 32° F. for each degree of rise in 
temperature. Five degrees C. equal nine degrees F. 

If the gas thus heated is so confined that it cannot expand, it 
will suffer an increase in pressure in the same proportion, that is, *4 j 
of its pressure at 0° C. for each degree Centigrade. If the gas, instead 
of being heated, is cooled, its shrinkage in the one case or its loss 
of pressure in the other will follow the same rule as above. Theoret- 
ically it follows that at — 237° C. — absolute zero — the gas would 
have no volume at all. Of course that is impossible, but at ordinary 
temperatures the gases behave as if the assumption were true. 


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Specific Heat. The temperature of a body and the heat it con- 
tains are two different things. A gallon of water at 100° F. contains 
twice as much heat as half a gallon at the same temperature. That 
is to say, twice as much heat was imparted to it in raising it to that 

Like quantities of different substances at the same temperature 
do not always contain the same quantity of heat. A pound of water 
contains more heat than a pound of oil or alcohol at the same tem- 
perature. It requires 7.7 times as much heat to raise a pound of 
water one degree in temperature as a pound of cast iron. 

The quantity of heat required to change the temperature of a 
given weight of a substance one degree, compared with that required 
to change the temperature of the same weight of water a like amount, 
is called the "specific heat" of that substance. 

Specific heat varies considerably for different substances, and for 
different temperatures and states of the same substance. Thus the 
specific heat of steam is much less than for water and varies slightly 
as the temperature and pressure of the steam is varied. 

British Thermal Unit. The quantity of heat required to raise 
the temperature of one pound of water one degree F. is known as the 
"British thermal unit" (B.t.u.) . Another unit is the "calorie", which is 
the quantity of heat required to raise the temperature of one kilo- 
gram (2.2046 lb.) of water one degree Centigrade. One calorie equals 
3.968 B.t.u. The B.t.u. is the unit generally used in this country 
for engineering calculations. The latest investigations lead to 
slightly different and more complicated definitions of the B.t.u. 
from the one given above, but this is near enough for practical 

Heat Value of Fuels. The number of heat units liberated by 
burning a pound of fuel varies for different fuels. The heat value for 
fuels is determined by experiment, and by calculation when the 
chemical composition is known. Due to the variation in the com- 
position of commercial gasoline, different samples will give different 
results, but for most calculations the figure of 19,000 B.t.u. Kerosene 
has a slightly higher value. 

Force. Force is defined as that which produces, or tends to 
produce, motion, and in practical work is usually expressed in units 





of weight, for example, pounds, kilograms, or tons. A force may 
exist without any resulting motion, and therefore without work being 
done. For example, the weight of any object represents the force of 
gravity attraction between the earth and that body. The atmos- 
phere exerts a pressure or force of approximately 14.7 pounds per 
square inch at sea level. 

Work. Work is done when force is exerted by or on a moving 
body, and is measured by the product of the force into the distance 
through which it is exerted. A convenient unit of work is the "foot- 
pound", which is the work done in lifting a weight of one pound 
against the force of gravitation a vertical distance of one foot, or 
exerting a force of one pound in any direction through a distance of . 
one foot. 

Power. Power expresses the rate at which work is done. If a 
foot-pound of work is performed in a minute, the power is small. 
If it is done in a second, the power is 60 times as great. The cus- 
tomary unit of power is the horsepower, which is 33,000 foot-pounds 
per minute. Whether a force of 33,000 pounds be exerted through 
one foot of distance, or one pound be exerted through 33,000 feet in 
the same time, the power is the same. 

Mechanical Equivalent of Heat. Heat may be converted into 
work or work into heat. Experiments have been made in which water 
was agitated in a closed vessel by means of paddles run by falling 
weights and the resulting rise in temperature of the water carefully 
determined. From these and other experiments, it has been ascer- 
tained that one British thermal unit is the equivalent of 778 foot- 
pounds of work. That is, a weight of one pound falling 778 feet, or 
778 pounds falling one foot, develops sufficient energy to raise one 
pound of water one degree F. in temperature. A horsepower, there- 
fore, equals 42.416 B.t.u. per minute. The combustion of one pound 
of either gasoline or kerosene liberates approximately 19,900 B.t.u., 
but the kerosene is heavier for equal bulk. One U. S. gallon of 
gasoline weighs about 5.6 pounds; of kerosene, about 6.25 pounds. 
The combustion of a gallon of kerosene per hour develops theoret- 
ically about 49 horsepower but the actual amount of energy obtained 
falls far short of this. Owing to heat losses in the boiler and exhaust, 
and to radiation, etc., only a small fraction of this energy can be 
converted into useful work. 


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Latent Heat. If water be heated in an open vessel it will reach 
a temperature of approximately 212° F. (100° C.) and will then boil 
away without further rise in temperature. The added heat is 
absorbed in converting the water into steam. 

It takes far more heat to convert water into steam than to raise 
its temperature. A pound of water heated to boiling from 32° F. 
absorbs only 180 B.t.u., but in boiling away at 212° F. it absorbs 
9G6 B.t.u. additional. At atmospheric pressure the vol- 
ume of the steam is 1645 times the volume of the water 
whence it came. This bulk of steam must displace an 
equal bulk of air, and part of the heat energy represented 
by the steam has been spent in pushing back the air to 
give it room. This will be made clearer from the sketch, 
Fig. 8, showing a long tube open at the top and containing 
a little water at the bottom. On top of the water is a 
piston, supposed to be air-tight and without weight or 
friction. If the water be boiled into steam, the piston 
will be pushed upward against the atmospheric pressure 
a distance equal to 1645 times the original depth of the 
water. The work in foot-pounds thus done will be 14.7 
times the area of the piston in square inches times the . 
distance in feet through which it has moved. Approxi- 
mately 7.45 per cent of the heat imparted to the steam 
represents work done against the atmosphere; the remain- 
der is spent in overcoming the mutual attraction of the 
molecules of water. The heat which has been absorbed 
by the change in state from water to steam without 
change in temperature is called the "latent heat of vapor- 

If a vessel containing water at 212° F., which is the 
atmospheric boiling point, be put under the receiver of 
an air pump and the air partly exhausted, boiling will 
take place spontaneously without further addition of heat. At the 
same time the temperature of the water will decrease, because part 
of the heat contained in it has been absorbed by the conversion of 
water into vapor. If the air pump keeps on working, the .water will 
boil continuously while its temperature steadily descends. If the 

Fig. 8. Expan- 
sion of Water 
into Steam 


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experiment be carried far enough, with the vessel so supported that 
it can absorb little or no heat from adjacent objects, and if the 
vapor given off be rapidly absorbed, for example, by placing a tray 
of quick-lime or sulphuric acid adjacent, the water may actually be 
frozen by its own evaporation. 

This experiment shows that the boiling point of water — and 
this includes other liquids also — is not a fixed temperature but 
depends on the pressure. All volatile liquids when exposed to partial 
or complete vacuum give off vapor; on the contrary, this vapor when 
subjected to pressure partly re-condenses and a higher temperature 
is needed to produce boiling. Under an absolute pressure of 147 
pounds or 10 "atmospheres", the boiling point is 356.6° F. At 500 
pounds absolute pressure the boiling point is 467.4° F. (242° C). 

The "total" heat of steam at the boiling point corresponding 
to a given pressure is the sum of its latent heat of vaporization and 
the heat contained at the same temperature in the water from which 
the steam was formed. The total heat of steam increases slowly, but 
the latent heat diminishes nearly in proportion as the boiling point 
rises. The space occupied by a given weight of steam diminishes 
approximately in proportion to the increase in pressure. In this 
respect the steam resembles a perfect gas without change of tempera- 
ture in accordance with Boyle's Law. Tables showing the pressures, 
temperatures, latent heat, etc., of steam are given in Kent and other 

The . experiment just cited of producing spontaneous boiling 
in water by exhausting the air above it, may be duplicated with hot 
water at any temperature and pressure. For example, the boiling 
point of water under 100 pounds absolute pressure is 327.6° F. 
If, in a boiler containing water at that temperature and pressure, 
the pressure be reduced to 50 pounds by the withdrawal of steam, the 
water will boil spontaneously, absorbing its own heat in doing so, 
until it reaches a temperature of 2$0.9° F., which is the boiling point 
for 50 pounds absolute pressure. 

Cause of Boiler Explosions. Owing to the property of giving 
off steam under reduction of pressure, every steam boiler constitutes 
a reservoir of energy which may be drawn upon to carry the engine 
through a temporary period of overload. In other words, the boiler 
will give out steam faster than the fire generates steam, the difference 


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being supplied from the heat stored in the water itself. This is an 
exceedingly useful feature of the ordinary steam boiler. At the 
same time, and for the same reason, it is a source of danger in case of 
rupture of the boiler shell. If a boiler explosion involved simply 
the release of the steam already formed it would not be so serious a 
matter; but when a seam starts to "go" the adjacent portions are 
unable to carry the abnormal strain put upon them, and the result 
is a rent of such proportions as to release almost instantly the entire 
contents of the boiler. The hot water thus suddenly liberated at 
high temperature bursts into steam until the whole mass drops to a 
temperature of 212 degrees, and this steam is many hundred times 
the volume of the water from which it came. It is to this fact that the 
violence of boiler explosions is due. 

To take an extreme case, if a boiler bursts under 500 pounds 
pressure, approximately thirty-seven per cent of the water it contains 
will pass instantly into steam, and at atmospheric pressure the volume 
of che steam w r ill be over 600 times the volume of the entire original 
liquid contents of the boiler. 

Automobile boilers and steam generators are so designed as 
to minimize the danger of explosion, and only ordinary care is needed 
to insure entire safety. 

Superheating. The foregoing paragraphs have dealt exclusively 
with steam at the boiling temperature due to its pressure. Such 
steam is called "saturated" steam. Steam will not suffer a reduction 
of temperature below this point; if heat be absorbed from it a portion 
will condense. On the other hand, steam isolated from the water 
whence it came may be raised in temperature indefinitely. It is then 
called "superheated" steam. The more it is superheated the more 
nearly does it act like a perfect gas. 

Superheated steam is preferred for power purposes to saturated 
steam, for the reason that the latter condenses more or less, both in 
the pipes on its way to the engine and in the engine itself. Steam 
which condenses thus is a total loss, and it is more economical to add 
sufficient heat to it before it reaches the engine to replaces radiation 
losses, etc., without cooling the steam to the saturation point. To 
accomplish this in automobiles, the steam from -the boiler is Jed 
through one or more pipes exposed to the maximum temperature of 
the fire. These pipes are called superheaters, or superheating pipes. 

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General Details of Steam Engine Parts. In Fig. 9 a plan view 
of a stationary steam engine is given, with the cylinder and valve 
chest shown in cross section, and with the various parts marked by 
letters. A view of a stationary engine is used because it is not so 
condensed as an automobile engine, and the parts are therefore 
easier to mark and pick out. The relations and names of parts are 
the same in an automobile engine. 

Fig. 9. Plan View of Typical Stationary Engine 

A, Cylinder. B, Outer cylinder head. C, Piston rod. D, Crosshead. E, Connecting rod. 
F, Crankpin. 0, Crank. H, Crankshaft. /, Eccentric. /, Eccentric rod. K, Eccentric 
crosshead. L, Valve stem. M, Steam chest. N, Steam pipe connection. PP, Flywheels. 
Q, Crosshead guides. R, Valve stem guide. S, Engine frame. T, Stuffing box. U, Piston. 
V, Wristpin. WW, Steam ports. X t Slide valve. Y, Eccentric strap. Z, Clearance space 
between piston and cylinder head at end of stroke. 

A is the cylinder to which steam is admitted through the pas- 
sages, or ports, W W, which connect it with the steam chest M. The 
opening and closing of these ports is accomplished by the movement 
of thfe valve X. Because of its shape, the valve here shown is called 
a D-slide valve. Other types of valves are piston valves and poppet 
valves, names which explain themselves. The valve is attached to 
the valve stem L and is guided by the valve-stem guide R. Motion 
back and forth is given the valve by the eccentric 7, which is a circu- 
lar disk on the crankshaft, with its center offset from the center of 
crankshaft 77. 

Returning to the cylinder, U is the piston, which is driven back 
and forth by the steam. Connected to the piston is the piston rod C, 


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which passes through the gland, or stuffing box T. This gland is for 
the purpose of holding the packing which prevents the escape of 
steam around the piston rod. The end of the rod, or crosshead D 
slides back and forth in the crosshead guides Q Q. To the crosshead 
is attached the connecting rod E f by means of the wristpin V. In 
the lower end of the connecting rod is the crankpin F. 

In steam automobile engines the flywheels P P are usually not 
needed and are consequently omitted. The rim of the gear wheel, 
when the engine is geared directly to the rear axle, has a slight fly- 
wheel action. 


The leading mechanical elements of the steam engine have been 
briefly described. It remains now to show the precise manner in 
which the steam is used. 

Elementary Slide Valve. Fig. 10 represents an elementary slide 
valve. In order to indicate the movements of the crankpin and the 
valve eccentric on one drawing, the crankshaft center is located at 

A. B represents the 

_ f ~ \ 

Fig. 10. Elementary Slide Valve — Valve in Mid-Position 

Fig. 11. 

Elementary Slide Valve — Inlet and Exhaust Ports 
Partly Uncovered 

Fig. 12. Elementary Slide Valve — Inlet and Exhaust Porta 
Fully Opened — Piston in Mid-Position 

crankpin center with 
the piston C at the 
inner end of its 
stroke. The larger 
dotted circle is the 
crankpin circle, and 
the small circle is that 
in which the center 
D of the eccentric 
moves. With the 
crankpin traveling as 
the arrow shows, the 
valve is in mid-posi- 
tion when the piston 
starts to move, and 
the first effect of its 
movement is to un- 
cover the steam port 
E, at the same time 
establishing com- 


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munication between port E f and exhaust port F f Fig. 11. At half- 
piston stroke the ports are wide open and the valve starts to return, 
Fig. 12. When the crankpin reaches the outer dead center G the 
ports are again closed. 

Use of Steam Cut-Off, A steam engine with valve arranged as 
above would take steam through the entire stroke, and would exhaust 
at boiler pressure. It would develop the maximum power of which it 
was capable at that pressure, but no use would have been made of 



Fig. 13. Theoretical Indicator Diagram for One-Half Cut-Off 

the expansion force of the steam. For this reason, all practical steam 
engines are made to admit steam only for the first portion of the 
stroke, that is, about one-half stroke or less, the remainder of the 
stroke being devoted to expansion. In Fig. 13, suppose A represents 
the position of a piston moving from left to right. The horizontal 
distance B C represents the stroke, and vertical distances represent 
steam pressures. D E is the line of zero pressure, and F C that of 
atmospheric pressure. Suppose steam is admitted at 50 pounds gage 
pressure during the first half of the stroke from G to H; the steam 
port then closes and the steam expands with diminishing pressure 
along the curve H I. Since work is the product of force into distance 
traveled, it follows that for each fraction, such as B J of the piston 
travel, the included area BG KJ will represent the work done 
during that portion of the stroke, and the area of the entire card 
BG H IC will represent the work done during the whole stroke. 


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Fig. 14. Theoretical Indicator Diagram for One- 
Quarter Cut-Off 

In the case under consideration, the area of the whole diagram is 
84.4 per cent of that which would have been produced if the steam 
had entered during the entire stroke, yet only half as much steam 
is used. 

Indicator Diagrams. A diagram such as Fig. K1 is called the 
"indicator diagram" or "indicator card", and is employed to study 

the internal action of 
the engine. The expan- 
sion curve of steam fol- 
lows Boyle's Law with 
sufficient closeness for 
practical purposes. Fig. 
14 is similar to Fig. 13 
except that the steam is cut off at one-quarter stroke, point H. 
In the foregoing, no mention has been made of the contents of 
the steam passages between the slide valve and the cylinder, or of the 
clearance volume between the piston and the cylinder head when the 
crank is on dead center. These clearance spaces cannot wholly be 
avoided, but it is desirable to reduce them as much as possible. It 
is customary in indicator cards to represent the clearance space 
by an area to the left of the actual indicator card. This area is 
F LG B in Fig. 13 and Fig. 14. Its volume averages about 5 per 
cent of the volume swept by the piston. Owing to the necessity 

of taking the steam in 
the clearance space into 
account, the actual steam 
consumption in Fig. 14 is 
a trifle more than half 
that in Fig. 13. 

Effect of Compres- 
sion on Indicator Card. 
The objectionable influ- 
ence of the clearance 
may be neutralized by 
closing the exhaust port 
before the piston has finished its return stroke, thereby trapping 
the remaining steam at atmospheric pressure and compressing it to 
boiler pressure. If this is done, none of the entering steam is wasted 

Fig. 15. Actual Indicator Card, Showing Compression 


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merely in filling the clearance space. Fig. 15 shows the effect of 
compression on an actual indicator card. It is not carried to boiler 
pressure, but only to point A. 

Another reason for using compression is to cushion the recipro- 
cating parts at the end of their stroke and prevent the shock which 
may otherwise occur on suddenly admitting live steam. 

Effect of High Pressure and Early Cut-Off. As Fig. 14 shows, 
no great advantage is gained when working with steam at 50 pounds 

by cutting off earlier 
than one-third stroke. If 
higher pressure is used, 
however, the cut-off can 
be 'considerably short- 
ened. Fig 16 is a theo- 
retical indicator diagram 
for 200 pounds gage 
pressure (214.7 absolute). 
The clearance is 5 per 
cent of the piston dis- 
placement, and cut-off 
occurs at one-tenth 
stroke. The weight of 
steam per stroke is about 
the same as in Fig. 14, 
but the work done by the 
higher pressure is nearly two-thirds greater. This shows strikingly 
the economic advantage of using high pressure, provided the cut- 
off is shortened to correspond. 

Effect of Adding Steam Lap. To produce a short cut-off, what 
is known as outside lap or steam lap is added to the edges of the slide 
valve A A, Fig. 17. To produce 
compression inside exhaust lap 
B B is also added. Figs. 18 and 19 
show how the valve mechanism 
is affected by these changes. In 
Fig. 18 the piston is about to begin its stroke, but the valve is no 
longer in mid-position. Instead, the eccentric has had to be ad- 
vanced through an angle, known as the "angle of advance", in order 

Fig. 16. 

Theoretical Indicator Card for One-Tenth 

Fig. 17. Section of Slide Valve, Showing 
Steam and Exhaust Laps 


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Fig. 18. 

Elementary Slide Valve, Showing Effect of 
Adding Laps 

Fig. 19. Elementary Slide Valve, Showing Adjustment 
of Lead 

to open the port as the piston starts to move. The necessary travel 
is also increased in order to accomplish the idle movement when all 
ports are closed. As the diagrams show, the valve reaches the end 

of its movement, re- 
*x turns, and closes the 
* - steam port while the 
piston is in the first 
quarter of its move- 
ment. It then con- 
tinues to move, but 
with only the exhaust 

It is customary, 
as Fig. 19 shows, to 
open the steam port 
a trifle before the 
piston begins its 
stroke in order to 
avoid wire drawing of the steam before the port goes fairly open. If 
this were not done, there would be an appreciable drop in pressure 
at the beginning of the stroke. The amount of this premature open- 
ing of the valve is called its "lead". 


Superheating to Avoid Cylinder Condensation. When steam 
expands its temperature drops by reason of expansion, causing the 
cylinder walls to assume an average temperature which slightly 
increases from contact with the hot steam and slightly diminishes at 
the end of every stroke. The hot entering steam condenses on the 
walls, and re-evaporates near the end of the stroke. This is very 
undesirable, and is avoided by superheating the steam sufficiently 
to compensate for the initial loss of heat to the walls. In addition, 
heat loss by radiation is minimized by lagging the cylinder walls and 
heads with asbestos, magnesia, or other non-conducting coverings. 

When steam is used at pressures above 100 pounds, compound 
engines are preferable, although not always used. 

Compound Engines. In a compound engine the work done by 
expansion is divided as nearly equal as practicable between two 


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cylinders, called respectively the high-pressure and the low-pressure 
cylinder. The high-pressure cylinder is the smaller in diameter, 
and it exhausts into the low-pressure cylinder instead of into the 
atmosphere. In the diagram, Fig. 20, showing the elements of 
a compound engine, the 
steam is being transferred 
from the high-pressure 
cylinder to the low-pres- 
sure cylinder. The steam 
expands by reason of the 
difference in the areas of 
the two pistons. 

A compound engine 
may be considered as 
though the steam were 
expanded wholly in the 
low-pressure cylinder, and 
the indicator diagrams of 
the two cylinders may be 
combined to show the total 
work done, by shortening 
the horizontal distances of 
the high-pressure card in proportion to its smaller piston area. 
Comparison of Indicator Diagrams for Stationary and Automobile 
Engines. Fig. 21 is a combined diagram from the high- and low- 
pressure cylinders of a stationary compound engine. Both cards are 
drawn to the same scale as regards stroke, but the low-pressure card 

reads from right to left. 
F is the point of admis- 
sion to the high-pressure 
cylinder. The slight peak 
at A is due to the inertia 
of the in-rushing steam. 
At B the admission valve 
closes. At C the steam is 
released and goes into 
the receiver between the 
cylinders. DE is the 

Fig. 20. Elements of a Compound Steam Engine 


Fig. 21. 

Indicator Diagram of a Stationary Compound 
Steam Engine 


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exhaust line, and E F the compression line. From DtoE steam passes 
from the high- to the low-pressure cylinder, the difference between 
the two lines being due to frictional resistance of the passages. At G 
the exhaust valve opens. /// is the compression line of the low- 
pressure cylinder. 

Use of Condensers. In the foregoing paragraphs steam is 
supposed to be exhausted at atmospheric pressure. In other words, 
the steam in the working end of the cylinder must overcome a back 
pressure of 14.7 pounds per square inch in the exhaust end. If the 
exhaust steam were discharged into a closed vessel and condensed, 
a vacuum would be formed containing only water vapor at a pressure 

Fig. 22. Stanley Radiator Fig. 23. Doble Radiator 

proportionate to its temperature. This would mean the addition of 
5, 10, or even 12 pounds to the height of the indicator card without 
having to increase the heat units put into the steam. To do this 
requires considerable apparatus — condenser, vacuum pump, etc., all 
of which it has been found inadvisable to install on an automobile. 

Condensers on steam cars are not for the purpose of increasing 
the total expansion by dropping below atmospheric pressure, but to 
condense the water at atmospheric pressure so as to be able to use it 
again and avoid having to fill the water tank so often. 

As shown in Figs. 22 and 23, both the Stanley and the Doble 
use condensers of the same general construction and appearance as 

366 Digitized by GOOgk § 


the radiators used on the ordinary gasoline car. The exhaust steam 
from the engine enters at the top of the radiator and is forced down- 
ward by the steam which is following. As it passes down the radi- 
ator, the air going through the spaces between the water passages 
cools it, until, by the time it reaches the bottom, it has been con- 
densed into water. 


Throttling and Reversing. Steam engines are regulated partly 
by the cut-off and partly by throttling. As has been pointed out 
above, it is impracticable to use a cut-off so short as to expand the 
steam to, or below, exhaust pressure. Beyond this point reduction 
of power must be had by throttling the steam on its way to the engine. 
The shortening of the cut-off, and the complete throwing over of the 
valve timing to the other side of the dead center to reverse 
the engine, may be accomplished by shifting the angular position 
of the eccentric on the crankshaft or by the use of one of several 
valve gears or linkages. 

Types of Gears. Up to the last few years the most common 
.gear was the "Stephenson Link", developed by Robert Stephenson 
and Company, in 1842. In locomotive work the Stephenson gear 
has been largely displaced by the Walschaert gear. Practically all 
the earlier steam automobiles used the Stephenson, but later some 
changed to the "Joy Gear", which is one of a number of radial gears 
employing linkages without the use of eccentrics. 

Stephenson Link. The Stephenson link is shown in Fig. 24. It 
consists of two eccentrics A on the crankshaft— one for the for- 
ward motion and the other for the reverse. The two eccentric rods 
are pinned to the link B, in which there is a curved slot. In the 
slot is carried the block C, which is a sliding fit and is pinned to 
the valve stem. 

By means of the hanger rod D and the reverse lever arm E, 
the link is moved up and down, so that the slide is in different posi- 
tions from the center of the slot. When the block is on one side of the 
link center it partakes of the motion of one of the eccentrics, and 
when on the other side of the motion of the other eccentric. Thus 
the valve timing is changed from the forward running position to the 
reverse by changing the position of the block in the curved slot. 


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It is a feature of the Stephenson link motion that by rocking 
the link toward (but not to) its mid-position the valve travel and 
cut-off are shortened, and this feature is utilized to improve economy. 
At the same time the lead is increased, that is, steam is admitted 
before the piston begins its new stroke. This is not a disadvantage 

Fig. 24. Stephenson Link Motion Used on Stanley Steam Cars 

at high speeds, as the fresh steam has a cushion effect on the recip- 
rocating parts. At low speeds, however, the engine runs jerkily, and 
consequently the cut-off is shortened only at medium to high speeds. 
Joy Gear. The Joy gear is a well known English development, 
which is used on a number of steam automobiles. Its operation may 

Fig. 25. Diagram of Joy Valve-Gear Mechanism 

be understood by referring to Fig. 25. A link is pinned at one end to 
the engine at // and at the other end to a link, w r hich in turn is pinned 
to the connecting rod at C. To this second link is pinned the link 


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D E 9 to the upper end of which is attached the rod E G, which moves 
the valve. At A on D E is pivoted the block A, which slides in vhe 
slotted guide, the guide being slightly concave on the side toward 
the valve. This guide is pinned to the engine frame at its center 
point P. In the position of the guide, as shown, the valve is in full 
gear for forward running, but if the guide is swung about the point P, 
by means of a connection at F, until it is in the position B F, the 
engine will then be in full reverse. 

As with the Stephenson, the moving of the Joy toward the half- 
way point shortens the cut-off. This gear has an advantage over the 
Stephenson in that the lead is not increased and the distribution of 
steam to the two ends of the cylinder on short cut-off is more nearly 
equal. The Joy gear also gives a rapid opening and closing to the 


Although makers have their individual preferences in engine 
types as regards the placing of the cylinders, compounding, and 
other features, the practice of using two cylinders has become almost 

Stanley. An example of the two-cylinder type is the Stanley 
engine, which, in the present models, is made in three sizes of the 
following bore and stroke: 3 J by 4J, 4 by 5, and 4 J by 6 J inches. 
This engine is geared directly to the rear axle by a spur gear mounted 
on the crankshaft, as shown in Fig. 26, and the frame rods are 
attached radially from the axle housing. The cylinder end is attached 
to the frame of the car. The rear-axle gear ratio in the small light 
runabout model is 30 to 56, and in the heavy delivery car is 40 to 80. 
With a gear ratio of 40 to 60 in one of the touring cars the engine 
turns over at 447 r.p.m. when the car is running 30 miles per hour. 

Both cylinders take high-pressure steam at both ends, the engine 
being of the double-acting, simple type. The steam chest, Fig. 27, 
lies between the two cylinders, with the D-slide valves driven by the 
eccentrics lying next to the drive-shaft gear. In Fig. 26 is shown 
theStephensoplinkby which the cut-off is hooked up and the reversing 
of the engine accomplished. This valve gear has been described in 
detail on page 23. The cross shaft, working the link, and the hook, for 
holding it in the normal position, are shown just to the left of A. 


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The hooking up is done by the left pedal, which can be released by a 

pedal beside it called the clutch pedal. 

Roller and ball bearings are used extensively in the Stanley 

motor. The crosshead bears on a plain crosshead guide, and the 

connecting-rod and eccentric- 
strap bearings are of the ball 
type. The counterweights are 
also shown in Fig. 26. 

Lubrication of the outside 
parts is effected by enclosing the 
gears, crankshaft, and other parts 
in a sheet-metal case, which is 
kept about half full of moderately 
thin mineral oil. The lubrication 
of the cylinder walls is accom- 
plished by feeding the oil into the 
steam line, and the special super- 
heated steam-cylinder oil recom- 
mended is given fully in a later 

The Stanley power pumps 
for water, fuel, and oil, shown in 

Fig. 26. Stanley Two-Cylinder Steam Engine, Fig. 46, are driven from the rear 
Showing Link Motion and Balanced Shaft ° 

Doble. The Doble engine, shown in full length section in Fig. 
28, is made up of two cylinders of the same size. It is of the simple- 
expansion double-acting type, and the interesting feature is that the 

uni-flow principle is employed. The 
cylinder bore is 5 inches and the 
stroke is 4 inches. 

On top of the cylinders are the 
valve chests. Each valve is made 
up in two pieces so that it may lift 
when the compression pressure ex- 
ceeds the steam pressure, as some- 
times happens in slow running. This 

Fig. 27. Cylinder Construction of 8tanley Construction alloWS the USe of high 

Steam Engine, Showing Steam . , . , . , , , 4 , 

chest in Center compression, which is desired at the 


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higher speeds. The gear used to control the valve motion is a 
modification and simplification of the Joy gear, Fig. 25. In the 

Doble gear the connecting 
and anchor links are done 
away with, and a straight 
rocker guide is employed. 
In starting, the cut-off is 
five-eighths stroke, and this 
same position is used for 
heavy pulling. For ordinary 
running, one-fifth stroke cut- 
off is used, w f hile for econ- 
omy and high speed it is 
£ reduced to one-eighth 
sj stroke. 
§ | By the uni-flow prin- 

* a2 ciple is meant that the 
3 | steam moves in but one 
2 J direction within the cylin- 
§ | der. It enters through the 
J .| inlet passage at the extreme 
. fea end of the cylinder, expands 

28 "3 

A | against the piston head, and 

e 2, passes out of the exhaust 

J ports, which are uncovered 

§ by the piston a little before 

it reaches the end of the 

stroke. It is claimed for 

this system that the thermal 

conditions are so good that 

the use of superheated 

steam, with its attendant 

troubles, is unnecessary. 

Aluminum is employed 
for the crankcase, with large 
cover plates, top and bot- 
tom, for easy access to the 
moving parts. The accessibility of the valve gear is very well 

371 Digitized by 



shown in Fig. 29. The case, which has its cover removed, con- 
tains all the moving parts of the engine with the exception of the 
valves and pistons; and, since the case and the axle tubes, which 
are bolted to it, are oil-tight, all these parts are kept in a bath of 

Fig. 29. Rear Portion of Doble Chassis, Showing Easy Access to Moving Parts 
Courtesy of General Engineering Company, Detroit , Michigan 

Fig. 30. Piston and Crosshead Guide of Doble Engine 

oil. This oil keeps comparatively cool and as there is no combus- 
tion, it does not deteriorate as in the gasoline car. 

A special design of long cast-iron gland is used for the piston 
rod at the cylinder, and there is a stuffing box where the rod passes 
into the crankcase. The crosshead guide is part of a cylinder, as 



shown in Fig. 30, giving a large bearing surface. Annular roller 
bearings are used for the big end of the connecting rod, for the 
crankshaft, and for the differen- 
tial. Hardened steel, running in 
hardened steel bushings, is used 
for all the other bearings. 

Being geared at practically a 
1 to 1 ratio to the axle shafts, the 
engine always runs at compara- 
tively slow spe£d. A 47-tooth 
pinion is carried on the engine 
crankshaft and to this is fastened 
the counterbalance. This gear 

. Fig. 31. Top View of National Power Plant 

meshes With One Of 49 teeth On fcfor London Steam Omnibuses 

. ..,_ ,. , . * rr,i i.- Courtesy of Society of Automobile Engineers, 

the differential spider. Inedir- New York aty 

Fig. 32. Separate Engine and Dynamo for Lighting National Busses 
Courtesy of Society of Automobile Engineers, New York City 

ferential is of the three-pinion bevel-gear type. Meshing with the 
axle gear is an idler, and then a gear on the electric generator, which 
furnishes current for the combustion system and the lights. 

National. In the National steam omnibuses of London, Eng- 
land, the engines are placed under the floor boards, Fig. 31, and, 




unlike any of the American engines* the two cylinders lie across the 
chassis. The drive is taken by a shaft to worm gearing at the rear 
axle. These engines have a Joy gear, and the pumps for the water 
and kerosene are driven from a cross shaft, which in turn is driven 
by a worm gear off the extension of the crankshaft, as is shown in the 
illustration. An interesting feature of the National chassis is the use 
of an entirely separate steam engine for driving the electric-lighting 
generator, which supplies the large number of lights used inside the 
busses. This auxiliary engine is shown in Fig. 32. 

From what has been said it must not be supposed that all auto- 
mobile steam engines use two-cylinder engines with either D or piston 
valves. The Pearson-Cox steam truck of England has a three- 
cylinder vertical engine with poppet valves in chambers at each side 
of the cylinders, and the whole engine looks very much like a vertical 
poppet-valve gasoline motor. 

A number of very heavy English trucks, or "lorries" as they call 
them, are driven by steam, and are very popular in England. These 
carry from 3 to 10 tons, and the boilers and parts of some of them 
are very large. 


Gasoline and Kerosene as Fuels. Energy for driving steam 
engines is derived, of course, from the fuel burning and forming 
steam from the water, the steam in turn doing mechanical work by 
its expansion in the engine. In an automobile it is of prime impor- 
tance that the fuel be as easily handled, carried, and purchased as 
possible. Of the commercial fuels, gasoline and kerosene come the 
nearest to these ideals and are, therefore, the most popular. Kero- 
sene is less expensive than gasoline, but does not vaporize at as low a 
temperature while, as a rule burners are specially designed for kero- 
sene, many modern burners will handle either of these fuels or a 
mixture of them. 

To burn either of these fuels the vapor must be mixed with air, 
which supplies the necessary oxygen for combustion. Either of these 
vapors, if mixed with the right amount of air, is highly inflammable 
and explosive, and therefore, care must be taken in storing and 
in filling the fuel tank, not to have open lights about — not even 
lighted cigars. 

374 Digitized by 




Burner Principles. Bunseri Burner. The purpose of the burner 
is first to vaporize the liquid fuel by heating it and then to mix it 
with enough air to produce the hottest possible flame under the 
boiler. In principle the burner is the same as the ordinary Bunsen 
burner, Fig. 33, in which the gas passes under moderate pressure 
through the small opening b. In going up the tube a it draws 
in a certain amount of air through the openings o, the fuel gas and 
air becoming well mixed in the tube before reaching the flame. In 
case either too much or too little air is mixed with the gas, the flame 
will run back through the tube 
a, and will burn at o. This is 
called "popping back", and not 
only takes away the effect of the 
flame but will ruin the burner if 
allowed to continue in operation 
in this way. 

Modifications for Automobile 
Work. In automobile work the 
burner is somewhat modified in 
order to act over a large area and 
to give a flame of more intense 
heat. For the purpose of feeding 
more gas, and to mix it more 
quickly with the air, the fuel is 
fed under considerable pressure. 

The correct mixture of air 
and fuel gas gives a blue flame, 
just slightly tinged with orange at 
the top, and burning rather close 
to the burner. If too much air is given the mixture, the flame will start 
a considerable distance above the burner and will be very blue. The 
excess air tends to cool the flame. Too little air is equally bad, for 
the combustion will then be incomplete and, since gasoline and 
kerosene are hydrocarbons, soot will be deposited on the surfaces 
above the flame. Such a flame is indicated by a yellow color. As in 
the ordinary Bunsen burner, poor mixtures are apt to pop back. 
When this happens the operator must turn off the burner and relight 
it. The popping back is indicated by a roaring sound. 

Fig. 33. Typical Bunsen Burner 


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Pilot Light As the demand for steam is not constant in an 
automobile, it is desirable to have the main burner come on and off 
automatically. In order to light the main burner whenever it may 
come on, a small light is kept burning continuously while the car is 
in use, whether running or standing still. It is even the practice of 
some owners to keep this pilot light, as it is called, lighted over night. 
Besides relighting the main burner when the car is running, the pilot 
is lighted first when firing up a cold boiler. The burning of the pilot 
serves to heat the vaporizer of the main burner as well as to light the 
main fire. The handling of the pilot in firing up will be taken up later. 
Due to its easier vaporization, gasoline is always used for the 
pilot-light fuel even when kerosene is used for the main burner. It 
is also quite general to have the two fuel systems separate, although 
both may be using gasoline. In starting up a cold system the pilot 
vaporizer must be heated by some outside means. This is done in 

several ways: one is to use 
a separate gasoline torch; 
another is to use an acety- 
lene torch instead of a gas- 
oline torch; and a third 
method is to light a little 
pool of gasoline below the 
vaporizer, similar to the 
method' used in many gas- 
oline cook stoves and plumb- 
ers' torches. 

Types of Burners. Dif- 

Fig. 34. Stanley Burner, Showing Vaporuer and ferent makers, of COUTSe 

Courts of Stanfe^M^cZriaae Company, ^ SOmewhat different COn- 

Newton, Massachusetts structions for their burners, 

but in all cases the fuel gas is vaporized by heat and mixed in a burner 
of the Bunsen type. As a fair example of all the burners, that of 
the Stanley will be described in detail, while short descriptions will 
also be given of other makes. 

Stanley. Either gasoline, kerosene, or a mixture of the two can 
be burned in the Stanley main burner. The burner, Fig. 34, consists 
of a corrugated casting with a large number of slots cut across the 
peaks of each parallel corrugation. Vaporization of the fuel takes 

376 Digitized by 



place in the two coiled tubes A A which lie directly over the fire. 
From the vaporizing tubes the gas flows at high velocity through the 
nozzles B B into the mixing tubes C C drawing with it the air 
necessary for good combustion. The mixing tubes lead under the 
burner, and combustible gas issues through the fine slots, where it 
burns with an intensely hot blue flame tipped with orange. No air 
currents are present to blow or cool the flame, for the burner casting 
excludes all air except that drawn in and mixed with the gas through 
the tubes C C. To adjust the amount of air to give the correct color 
to the flame, bend the nozzles closer to the opening of the mixing 
tube for less air, and vice versa. 

Between the two main-burner vaporizer tubes is located the 
pilot light, which is a small independent casting. The pilot burns 
gasoline, supplied from a separate tank, irrespective of whether the 
main burner uses gasoline or kerosene. Due to the position of the 
pilot, it keeps the main-burner vaporizer warm when the main burner 
is shut off by either the automatic or hand valve controlling it. When 
the main burner is turned on, the pilot flame ignites the gas. Since 
the pilot is independent of the main-burner valves, it remains lighted 
until turned off by its own hand-operated valve. The heat from the 
pilot is sufficient to hold steam in the boiler for several hours after the 
car is stopped and the main burner shut off. 

In starting up the pilot of the Stanley when cold, an acetylene 
torch is played on the pilot vaporizer to vaporize the first gasoline, 
after which the heat from the pilot light itself keeps the pilot vapor- 
izer warm. The acetylene is carried in a "Prest-O-Lite" tank and 
turned on by a valve at the tank. The torch lights by simply apply- 
ing a match, and should be played on the pilot vaporizer until it is 
sizzling hot, which takes between 15 and 30 seconds. The torch is 
then moved so that the flame enters the peek-hole, lighting the pilot, 
after which the torch is played upon the upper part of the vaporizer 
for 15 to 30 seconds, until the main burner nozzles are sizzling hot. 

After closing the acetylene-tank valve the main-burner valve is 
opened and closed quickly several times until the gas from the main 
nozzles is dry. It is then left open, being lighted by the pilot flame. 
The pilot nozzle is provided with a wire which is filed off on one side 
to allow the passage of the gas. If the pilot light does not seem to 
burn strongly, it can be cleaned while burning by turning the outside 


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screw back and forth with a screwdriver. If this does not suffice, 
the wire should be taken out and cleaned; it is good practice to do 
this every day before firing up. The color of the flame can be adjusted 
by bending the nozzle tube to bring the nozzle in or out from the 
mixing tube, the same as is done in adjusting the main burner. 

In the older models of Stanley cars, which used only gasoline as 
the main-burner fuel, the pilot fuel system was a branch of the main 
system, and the pilot vaporizer was heated by a gasoline torch. 

Fig. 35. Section through Combustion Chamber and Boiler of Doble Car 
Courtesy of General Engineering Company, Detroit, Michigan 

Doble. Very radical departures from the long-established Bun- 
sen type of burner have been made in the combustion system on the 
new Doble car. The fuel is ignited by electricity and there is no 
pilot light. Kerosene is used for both starting and running and is 
fed from the main fuel tank to a float chamber by an air pressure of 
three pounds per square inch. From the float chamber, which is of 
the standard gasoline-carbureter type, the fuel passes through a spray 
nozzle, which is located in the throat of a Venturi tube leading to 
the combustion chamber. 


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Air for the support of the combustion of the fuel is drawn 
through the radiator by means of a multiple-vane fan driven by a 
small electric motor. It passes the jet with sufficient velocity to 
draw out the fuel and atomize it. Owing to the enlarging of the 
passage directly beyond the throat, the velocity is decreased in order 
to give time for the complete 
combustion of the gas by the 
electric spark, which takes place 
at this point. 

The combustion chamber, 
Fig. 35, is completely closed and 
lined with a highly refractory 
material. As soon as the com- 
bustion has been started, the 
electric spark is automatically 

i j, a j ^i_ i_ • f .1 Fig. 36- Ofeldt Blue Flame Kerosene Burner 

ShUt Off, and the burning Of the Courtesy of F. W. Ofeldt and Sons, 

• , • ,«i •. N vac k-on-t he-Hudson, New York 

gas is continuous until it is 

stopped by the action of the automatic steam control, as described 
later. The lining of the chamber not only has the property of 
resisting high heats, but it holds and gives back the heat so as to 
assist in completely burning the gases. The combustion chamber 
is also well illustrated in Fig. 41, page 40. 

Ofeldt. The Ofeldt burner, Fig. 36, is designed especially for 
the use of kerosene as a fuel. Forming the foundation of the burner is 

Fig. 37. Kerosene Burner, Used on National Busses with Starter 
Courtesy of Society of Automobile Engineers, New York City 

a galvanized iron pan, lined around the sides with millboard asbestos. 
In the bottom of the pan are drilled rows of small holes. Since these 
holes are in straight lines under the burner pieces, and of equal size, 
they admit even amounts of air throughout the lengths of the burner 

Cast iron is used for the burner pieces, which radiate from a 


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central gas-distributing chamber, into which they are screwed. The 
gas flows through fine slots cut in the burner pieces. Surrounding the 
mixing tube is the main vaporizer A, which passes through the outside 
of the pan, ending in the nozzle B at the opening of the mixing tube. 
The mixing tube is a part of the central gas-distributing chamber. 
Attached below the burner pan is the pilot D, where its flame 
heats both the main and the pilot vaporizers and the mixing tube. 
By means of a hand valve the pilot flame can be adjusted to keep up 

steam when the main burner 
is out, or it can be turned 
down so as to keep only the 
main vaporizer warm. 

A comparatively low 
pressure is used on the 
Ofeldt system, the fuel being 
kept under about 60 pounds 
per square inch. 

National. Kerosene is 
used as the fuel in the 
^National busses. These 
burners are quite different 
in appearance from those 
described above, as is shown 

Fig. 38. Stanley_Fire-Tube Boiler in Fig. 37. 


Classification. In stationary steam-power plants there are two 
distinct classes of boilers, the fire-tube and the water-tube. These 
two types are also used in automobile work, together with a third 
type, the flash boiler, which is a development of the water-tube type. 

Fire-Tube Boilers. In principle the fire-tube boiler is like a big 
tea-kettle filled with vertical tubes, which run from the bottom to the 
top for the purpose of carrying up the flame and hot gases. This 
construction gives a very large surface on one side of which are water 
and steam and on the other flame and hot gases. 

Stanley. One of the simplest of the fire-tube boilers is the 
Stanley, Fig. 38. This is made up of a pressed-steel shell, which 
includes the lower head, the upper head being a separate piece. 


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Between these two heads run a large number of tubes of ii inch 
outside diameter, which are expanded into the heads by a taper 
expanding tool. Stanley boilers are made in three sizes, 20, 23, and 
26 inches in diameter and 14 and 16 inches in height, respectively. 
The number of tubes is 550, 751, and 999, giving 77, 104, and 158 
square feet of heating surfaces. To keep down the radiation losses, 
the boiler shell is lagged with asbestos, and the strength of the shell 
is greatly increased by winding it with steel piano wire. 

To keep a reserve of steam, and to have the steam free from 
particles of water, the boiler is kept only about two-thirds full of 
water, the upper space being filled with steam. To further insure 
dry steam at the engine the steam is led by a pipe from the top of the 
boiler down to a superheating coil directly over the burner. 

Fusible Plug. As a warning against too low water the side of 
the boiler is provided with a fusible plug, held in a fusible-plug tube 
which, in turn, screws into a steel fitting. The elbows on this fitting 
are made on a taper and are driven into two short tubes in the boiler. 
As long as the water level is above these tubes the circulation prevents 
the plug from melting. If the water gets below the plug and about 
3 inches from the bottom of the boiler, the plug will melt and the 
noise of the escaping steam wfll warn the operator of the danger — not 
danger of an explosion of the boiler, but danger of doing the boiler 
damage by heating it without water. There are other means by 
which the operator may know that the water is getting low before it 
gets low enough to blow out the plug, and these will be taken up in 
detail later, together with the causes of unexpected low water and 
other points. 

The fusible plug may melt out, not only from low water but also 
because of dirt or something retarding the circulation of water around 
the tubes or fittings. The blowing off of the steam will usually remove 
the obstruction. If the escaping steam is dry, it is a sign that the 
melting has been caused by low water, but if it is wet the trouble is due 
to faulty circulation. It is good practice to replace the fusible plug 
once every two or three weeks, doing this when the boiler is cold. 

Since the addition of the condenser to the Stanley in 1915, these 
boilers have been made without the fusible plugs. Among other 
improvements in these boilers is the brazing, or welding, of the tubes 
in the lower heads. This is to prevent any trouble from oil, which 


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might be carried over into the condensing system. Before the boilers 
are turned out from the factory, they are tested by a water pressure 
of from 1500 to 1800 pounds per square inch. 

Water-Tube Boilers. Water-tube boilers also are made up of 
tubes, but in this case the tubes carry the water and steam inside and 
the fire and hot gases pass overthe tubes. The metal hood over this 
type of boiler carries no pressure, but merely serves to keep in and 
direct the hot gases. In stationary practice the tubes are often 
straight or only slightly bent, but to economize space the automobile 

boiler has the tubes coiled to give the 
most surface to the fire in the least 
possible space. 

Ofeldt. The Ofeldt safety water- 
tube boiler, Fig. 39, is built about 
a central standpipe of 5 inches or 
more in diameter, with a bottom of 
£-inch metal welded in. Threaded 
ipto the upper end of the standpipe 
is a steel cap with three arms, to the 
ends of which the sheet-metal hood, 
or cover, is fastened. 

The object of the standpipe is to 
hold a reserve of water at the bottom 
Fi«. 39. ofeldt Safety Water-Tube and of steam at the top, and to dis- 
tribute the water to the coils. In 
the coils and standpipe the reserve of water varies from 3 gallons in 
the small sizes to 8 gallons in the 24-inch size. 

Water is fed to the bottom of the standpipe, from where it flows 
into the coils. As it passes up the coils it turns into steam. A 
pipe from the center of the standpipe carries the steam down to 
the superheater, which lies under the boiler directly over the burner, as 
shown in Fig. 39. From the superheater the steam is carried by the sec- 
ond straight pipe back to the top of the boiler and then to the engine. 
These boilers are supposed to supply steam at 250 pounds pres- 
sure but are tested up to 1000 pounds per square inch. 

Dobk. Almost as great a departure from ordinary practice has 
been made in the Doble boiler as in the combustion system previously 
described. The generator is of the water-tube type, with the tubes 


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arranged in rows, which are really separate sections, Fig. 40. There 
are 28 of these sections in the generator part of the boiler. The 
tubes are made from seamless drawn-steel tubing of about £-inch 
diameter and are swaged down to a diameter of about f inch at the 
ends. These ends are welded into the top and bottom headers, 
thus making each section a continuous piece of steel. 

Besides the 28 sections of tubes in the generator portion, there 
are 8 more sections in the economizer or feed-water heater. The 

Fig. 40. One Section of Doble Boiler 
Courtesy of General Engineering Company, Detroit, Michigan 

arrangement of all these sections is clearly shown in Fig. 41, the view 
being cut across each of the 36 sections, similar to Fig. 40. The 
picture does not show all the details but has been arranged to give an 
idea of the general layout and the direction of flow of the hot gases and 
of the water and steam. The boiler sections are completely covered 
over, except at the bottom, by a f-inch wall of heat-resisting and 
insulating Kieselguhr material. Over this is a planished iron jacket. 
All of the sections are connected together by headers, which run 
along the sides of the boiler. One of the features of the construction 
is that if anything should go wrong with a section of tubes, it can be 


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very easily cut out of operation by means of the side headers, until 
such time as it is convenient to replace the section. 

In Fig. 41, the direction of flow of the hot gases of combustion 
is shown by the heavy arrows, while the flow of the water and steam 
is indicated by the small arrows. From the combustion chamber at 
the bottom of the boiler, the gases pass upward ai\d then over the top 
of the fire wall between the generator proper and the economizer. 
Here they turn and pass downward in order to escape through the 

Fig. 41. Section through Doble Boiler, Showing Combustion Below and Economizer 
Section at Right 

exhaust at the bottom. It should be noted that the power-driven 
feed pump forces the water in an upward direction in the economizer 
tubes, exactly opposite to that of the gas flow outside of the tubes. 
From the top headers of the economizer sections, the water over- 
flows through a manifold to the lower headers of the generator 
sections. An automatic valve controls the feed water, so that the 
water in the boiler, under normal conditions, stands about half-way to 
the top. On the road, the usual pressure is around 600 pounds per 
square inch, which is maintained by an automatic valve controlling 



the fuel supply. Each section of the boiler is tested to a water pres- 
sure of 5000 pounds per square inch. The actual bursting pressure 
is said to be over 8000 pounds. As a precaution against any danger, 
however, a safety valve is attached to the boiler. 

Flash Boilers. Flash boilers differ from the fire- or water-tube 
types, both of which have a reserve of steam, in that the steam is 
generated only in the quantity demanded each moment by the 
engine. These boilers consist of a continuous metal tube in one or 
more coils lying over thfe burner. As the water from the reservoir 
passes along the tube it gets hotter and hotter until at some point 
in the tube it bursts into steam. During the rest of its travel the 
steam is superheated. 

As practically no steam is kept in reserve, the capacity of the 
boiler and burner must be great enough to supply at once the maxi- 
mum demand for hill climbing. The relations of water and fire must 
be nicely balanced at all times to prevent too much superheat on one 
hand and wet steam on the other. 

Safety against a dangerous explosion is the leading argument for 
the flash type of boiler. Since there is no reserve of steam or hot 
water under pressure, there is no large amount of energy to be 
liberated in case of a rupture of any part of the boiler. 

Serpollet System. In the early days of steam automobiles a 
Frenchman named Serpollet reduced the amount of water in a boiler 
to an extremely small amount. To give the maximum of heating- 
surface area together with a minimum of cross-sectional area, the 
tubes were made a U-section instead of circular; this type, however, 
was abandoned later. 

With the Serpollet system the fuel and watef were fed simul- 
taneously, one lever varying the strokes of both pumps. To avoid 
trouble from extreme superheat, single-acting pistons and poppet 
valves were employed. The valve cut-off was variable and worked in 
conjunction with the fuel and water supplies. Since there was no 
reserve of energy to the system, it took a great deal of skill to handle 
it smoothly, especially in hilly country. 

White. A great improvement over the Serpollet system was the 
flash generator of the White Company. Although the White steam 
cars were discontinued in 1911, they were /the leading example of the 
flash system in this country. 




In the White generator there was a sufficient supply of water to 
serve as a reserve in cases of sudden demand. Referring to Fig. 42, 
it will be noted that the boiler was made up of several rows of tubes, 
each coiled in a horizontal plane, and each connected to the row 
below by a tube which first passes to the top of i the boiler. Unlike 
the ordinary fire-tube or water-tube boilers, the water entered the 
White boiler at the top, through the pipe 128. The upper coil was in 
the coolest portion of the gases from the burner. After passing 
through the top coil, the water flowed through the tube at the end of 
the coil, being carried up and over the top of the boiler and then 
down to the second coil, and so on down from coil to coil. Being 
nearer the burner, each coil was hotter than the one above, and, 

Fig. 42. Generator, Burner, and Fuel Connections Formerly Used on 
White Steam Cars 

since the vertical pipes at the ends of the coils kept the hot water 
from circulating back to the coil above, there was some point in the 
lower coils where the water burst into steam. The steam became 
superheated during the remainder of its travel through the coils and 
left the boiler by the pipe 129. 

These principles of construction were held to in all the White 
steam cars from 1904 to 1911 inclusive. Because of the strength of 
the small-diameter tubes and the small amounts of steam and water 


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in the boiler at any one time, it was possible to carry a working 
pressure in these generators of 600 pounds per square inch. 

Special Types. Lane. The Lane boiler, Fig. 43, was a combina- 
tion of the fire-tube and flash systems. The main part of the boiler 
was of the fire-tube type, with very 
large tubes. Above this were several 
coils of brass tubing, the water entering 
the top and getting hotter as it passed 
down the tubes until it was partly con- 
verted into steam by the time it passed 
into the main part. The water was 
here separated from the steam, falling 
to the bottom of the boiler, while the 
steam was superheated by coming in 
contact with the hot upper portion of 
the fire tubes. 

National. For the National Lon- 
don busses a water-tube boiler is used, Fi «- 43 l*™ Boi,er 
and these stand a great deal of abuse, often being run dry by the 
carelessness of the drivers. As is shown in Fig. 44, these boilers are 

Fig. 44. Water-Tube Boiler Used on National London Busses 
Courtesy of Society of A utomobile Engineers, Sew York City 

built around a central steel drum, which is pressed from a single piece 
of metal. 


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Besides the main units of burner, boiler, and engine on the steam 
automobile, there have to be many other small units, most of them 
automatic in their operation, for the control of the fire, water feed, 
and engine to meet the conditions of the wide variations in road and 
driving conditions. These are the power pumps, the hand pumps, 
valves, feed-water heater, condensers, and others. 

Check Valves. In the lines where it is desired to have the fuel, 

water, or steam pass in but one direction there are placed valves 

which allow only this one-way passage and are known as check valves. 

There are several types, including poppet, hinged, and ball checks. 

The latter, Fig. 45, is very largely used and consists of a ball which 

rests on a seat forming a ground, fluid-tight 

joint. When the fluid is passing in the desired 

direction it lifts the ball off the seat. The 

body of the valve is so made that it keeps the 

ball from being carried on down the line with 

the fluid. As soon as the direction of flow or 

pressure changes to the opposite direction the 

Fig. 45. Crane Ball Check bal1 dr °P S ° nt ° its Seat > closing the Valve 

Valve against this opposite flow. 

Check valves are used in many places in the fuel, water, and 
steam lines, as is indicated by the diagrams further along. For 
instance, there are check valves on the inlet and outlet sides of the 
water pumps. When the piston is on the suction stroke, the inlet 
check is open while the outlet check is closed, keeping the water 
already pumped from being drawn back. As soon as the piston 
starts on the delivery stroke the inlet check closes and the outlet 
valve opens. This action applies to all the types of check valves. 

If dirt lodges on the seats of a check it will leak and, if the dirt 
cannot be forced off by vigorous action through the valve, the valve 
must be opened up and the seat cleaned and possibly ground. In 
most check valves this can be done without removing the whole 
valve from the line. 

Fuel System. Considerable fuel-carrying capacity is always 
provided in automobiles, and for this reason there should always be 
enough in the car for more than one run. Before starting out it is 


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always well to see that there is plenty of fuel in the main and pilot 
supply tanks. Not only is running out of fuel on the road very 
inconvenient, but the running-dry of the tanks may air-lock the 
pumps and cause a loss of considerable extra time in getting the 

Fig. 46. Power Pumps of Stanley Engine 

system back into smooth action. The above applies equally well to 
the water supply. 

As mentioned in the section on burners, the fuel is fed under 
pressure. In some cases the pressure is carried on the main tank, 
while in other cases it is carried by air or spring pressure on small 
auxiliary tanks. The power and 
hand pumps on steam cars are 
of the plunger type. 

Due to the interrelations be- 
tween the demands for steam, 
water, and fuel and the auto- 
matic devices, one controlled by 
the other, it is difficult to deal 
separately with the various 
units. For this reason one com- 
plete fuel, water, and steam sys- 
tem will be discussed and then 
descriptions of other makers' units and methods of operation will be 
taken up. The Stanley system will be used to show the relation and 
operation of the various units. 

Stanley Fuel, Water, and Steam Systems. Fuel System. On the 
Stanley cars the main fuel tank is carried under atmospheric pressurr 
and the fuel is drawn from the tank by the power-driven pump, 
Fig. 46. In series with the power fuel pump is a hand pump for use 

Fig. 47. Fuel Pressure Tanks on Stanley Cars 


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when the engine is not running or if the power pump should be out 
of order. The small pressure tanks on the Stanley are shown in 
Fig. 47. The fuel does not flow through the left tank, marked 2, but 
merely rises and falls in it, the tank acting 
as a pressure equalizer between the strokes 
of the power pump, similar to the standpipe 
in many city waterworks systems. Tank 
number 1, on the right, is filled with com- 
pressed air, which is supplied by the power- 
driven air pump or by the hand air pump. A 
pressure gage on the dashboard shows the 
operator what the pressure is on the tanks. 
From the auxiliary tanks the fuel passes to 
the vaporizer. 

Since the fuel power pump has a capacity 
„ , Q _ . _ .. greater than that usuallv demanded bv the 

Fig. 48. Stanley Gasoline ° * *- 

Automatic Valve burner an automatic by-pass valve, called the 

fuel automatic relief, Fig. 48, is placed in the line. When the fuel 
from the pump is at a higher pressure than is being carried on the 

Fig. 49. Stanley Fuel System 
Courtesy of Stanley Motor Carriage Company, Newton, Massachusetts 

pressure tanks, the needle valve of this fuel automatic relief is raised 
and part of the fuel is returned to the main tank, as shown in the 
layout of the fuel system, Fig. 49. 

Should this needle valve fail to seat properly, it is probably due 


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to dirt between the needle and the seat. This can often be removed 
by taking the tension off the spring by unscrewing the adjusting nut 
and then pumping fuel with the hand pump. If this does not cure 
the trouble the whole valve should be taken 
apart and cleaned and, if necessary, the needle 
ground into the seat. 

Beyond the pressure tanks there is a fuel 
filter which should be watched for leaks and 
cleaned evpry once in a while. Near the tanks 
is also a pressure-retaining valve, which may be 
closed by hand when the car is left standing, 
the purpose being to keep the pressure on the 
tanks, as it might otherwise be lost, due to slow 
leaks in the lines, and thereby necessitate the 
pumping-up of pressure by hand. 

Actual fuel supply to the vaporizer, and 
hence to the burner, is governed by the steam 
automatic regulator, or "diaphragm regulator", 
as it is sometimes called, Fig. 50. This regula- 
tor governs the relation between the steam 
pressure and the fuel supply to the burner. It 
consists of a metal diaphragm, clamped 
between the cap and the body. When the 
steam pressure rises above the predetermined 
amount, the pressure against the diaphragm 
causes it to bulge and thus move the rod 
attached to it so as to keep the ball valve from 
leaving its seat, thereby shutting off the fuel to 
the boiler. 

The strength of the spring determines at 
what steam pressure the fuel is shut off. To 
regulate the strength of the spring the adjusting screw is moved 
in or out. The valve stem is provided with a stuffing box which 
can be tightened up to stop leaks through the gland. The screw 
locks the gland in place after the adjustment is made. Care must 
be taken not to get the gland too tight. 

Upon the older Stanle^f models, in which gasoline was used for 
the fuel of the main burner as well as for the pilot Hght, the line for 

Fig. 50. Stanley Steam 
Automatic Valve 


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the latter was a branch of the main fuel line. In the newer models, 
the pilot system is entirely separate, so that kerosene may be used for 
the main burner. The pressure on the separate gasoline tank is 
pumped up by a hand pump and should be kept at from 20 to 30 
pounds per square inch. In leaving the pilot burning over night the 
pressure will not fall over 5 to 10 pounds. 

Water and Steam System. From the main water tank the water 
is drawn by two opposite power-driven pumps, Fig. 46, and follows 
the course shown in Fig. 51. A hand pump is also provided for use 

Fig. 51. Diagram of Stanley Water System 
Courtesy of Stanley Motor Carriage Company, Newton, Massachusetts 

when the car is standing still or in case of a failure of the power 
pumps. Beyond the pumps are by-pass valves, the opening of which 
allows the water to return to the supply tank. The rear by-pass is 
operated by the usual type of handle, while the one in front is con- 
trolled by a lever on the steering post. The handling of these by-pass 
valves will be taken up in relation to the general operation of the car. 
On the way to the boiler, the water passes to the water-level 
indicator, which is explained in detail in the following paragraph, and 
then to the feed-water heater. Over the\ater pipes in the feed- water 
heater the exhaust steam from the engine is passed. In this way 


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much of the otherwise waste heat of the exhaust is given back by 
heating the water before it reaches the boiler, resulting, of course, in a 
saving of fuel. The feed-water heater also serves as a muffler for the 
sound of the engine exhaust. 

The water-level indicator is for the purpose of showing the opera- 
tor the amount of water in the boiler. It consists of three tubes, Fig. 
52, M , N, 0, which are brazed together. The middle one N is a part 
of the water column, that is, its lower end connects with a pipe leading 

Fig. 52. Diagram Showing Stanley Low- Water Automatic Valve with 
Three-Tube Indicator Body 

to the bottom of the boiler and its upper end is in communication 
with the top of the boiler, so that the water stands in this column at 
the same height that it does in the boiler. At the lower end of tube 
N is the low-water try cock. 

Tube M, at the left, is part of the water system from the pumps 
to the boiler and, when the car is running, water is constantly passing 
through it. The standpipe is closed at its upper end and at its 
lower end is connected by a copper tube to the glass water glass on 


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the dashboard in front of the driver. The standpipe, tube, and glass 
form a U-tube which is filled with water, the level of which, when cold, 
stands about an inch above the bottom of the glass. 

If the water level in the boiler, and therefore in the tube N, is 
above the top of the standpipe 0, the cold water passing through M 
on its way to the boiler will keep the standpipe comparatively 
cool, and the water in the glass will show about an inch above the 
bottom; but if the water in the boiler falls below the top of the stand- 
pipe, it will no longer keep cool and the resulting heat will turn some 
of the water in the standpipe into vapor. Since the end of the stand- 
pipe is closed, the pressure of the vapor will cause the water in 
the glass to rise, showing the driver that the water in the boiler is 
getting low. 

It is important to remember that when the water is high in the 
glass it is low in the boiler. It should also be noted that the gla^s 
gives the correct reading only when the car is running, and that when 
the boiler is cold the water in the glass will be at the bottom whether 
the boiler is full or empty. A false reading of the glass may also 
occur from the heating-up of the indicator body when the car is left 
standing with steam up. This will make the water rise in the glass, 
apparently showing the water to be low in the boiler even though it 
were full. Directly upon starting the car, water will be pumped 
through tube M and the indicator body will cool down, giving a 
correct reading in the glass. 

To fill the standpipe, U-tube and glass with water, the plug is 
removed from the top of the standpipe and water is poured into the 
glass faster than it can flow out of the standpipe. When all the air 
has been forced out in this way, the screw is replaced while the water 
is still running, but is screwed down only lightfy. The water is then 
shut off and, when the level in the glass has gone down to about an 
inch above the bottom, the screw in the top of the standpipe is 
tightened up. 

In freezing weather an anti-freeze solution should be used in the 
U-tube and glass. This can be made of equal parts of glycerine and 
water or of alcohol and water. A test of the indicator can be made 
when steam is up by opening the low-water pet cock until the water 
rises in the glass and then pouring cold water over the body of the 
indicator, which should cause the water in the glass to fall. 


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When the boiler is ctold the amount of water in it is determined 
by opening the low-water pet cock. If water flows it shows that there 
is enough in the boiler to allow firing up. If no water comes and a 
wire run in the pet cock shows that it is not stopped up, water should 
be pumped in the boiler by hand. When trying the water level by 
the pet cock the water should be allowed to run several seconds so as 
to be sure that it is not merely the condensation which may have 

If dirt or incrustation should stop up the lower end of the water 
column, it would cause false readings of the indicator and try cock. 
It is therefore important that this be guarded against by blowing 
down the boiler regularly. The procedure in blowing down will be 
referred to later. 

Another protecting device of the Stanley is the low-water auto- 
matic valve, which in its action and location is closely connected to 
the water-level indicator. The purpose of this valve is to shut off 
the fuel supply in case the water becomes low in the boiler. As shown 
in Fig. 50, it consists of a valve B in the fuel line, an expansion tube 
D and two rods C, the latter forming a framework or support. 

When the water in the boiler and water column gets below the 
try cock, the expansion tube D fills with steam and the heat of this 
steam causes the tube to become longer. This expansion moves the 
valve stem E, connected to the end of the tube, and this closes the 
valve, shutting off the fuel to the burner. 

In case the low-water automatic valve closes, first make sure that 
there is water in the main tank, and that the pumps are working 
properly. Then with both by-pass valves closed run the car as far 
as it will go. By this time the pumps probably will have delivered 
enough water to cover the bottom of the expansion tube, allowing the 
fuel valve to open again. If not, the engine can be run with the 
wheels jacked up or water can be pumped by the hand pump. 

There are four other accessories to the Stanley and other power 
plants, which have not yet been mentioned : the safety valve, steam 
gage, siphon, and oil pump. 

The safety valve is connected to the boiler and will blow if the 
steam pressure exceeds the amount for which the valve is set. The 
steam gage is placed on the dash and indicates the steam pressure 
in pounds per square inch. The steam itself does not actually enter 

396 Digitized by G00gle 



the gage, but the pressure in the system is communicated to the gage 
by means of a tube filled with oil, which will not freeze in winter. 

When it is desired to draw 
water from a water trough or 
some other place from which it 
cannot be run into the tank from 
a faucet, the siphon is used. This 
is a hose, a branch of which is 
I bBSI ^ connected to the steam system 

by a hand valve. One end is 
placed in the tank-filler opening 
and the other end, which is pro- 
vided with a screen, is put in 
the supply of water. The steam 
is turned on and, due to an in- 
jector action, draws the water up 
into the tank. 

Driven by the same mech- 
anism which drives the Stanley 
fuel and water pumps, is the oil 
pump, Figs. 46 and 53. From the 
oil tank the pump forces the oil 
through the sight feed on the 
dash, from which it is led into 
the steam line to the engine. 

In the oil pump, Fig. 53, the 
plunger A is set in its extreme 
foreposition, so that the end will 
just come to the outlet. This is 
done by removing the delivery 
stub cap and delivery check ball 
and inserting a small wire in the 
outlet. When the driving cross- 
head is in the extreme position, 
the plunger should come to a 
point where it will strike the 
wire; the lock nut B is then tightened. This adjustment should be 
looked to if the position of the driving crosshead befcomes changed. 


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To vary the amount of oil pumped, the distance between the 
end of the adjusting piston C and the pump inlet is varied. The 
shorter this distance the less the amount of oil pumped. The adjust- 
ment is made by removing the cap D and adjusting the set nut E. 
If the oil tank is allowed to run dry the pump may become air-locked, 
and it is then necessary to disconnect the copper pipe and work the 
pump until the air is expelled. 

All ordinary steam-cylinder oil is not suitable for use in these 
engines because of the high degree of superheat. The Stanley 
Company recommend either the "Harris superheat steam-cylinder 
oil" or the "Oilzum high-pressure superheated steam-cylinder oil". 
Other makers recommend different classes of oils best suited to their 
particular engines and these will be noted later. 

Now that a general idea of the make-up and operation of the 
power-plant accessories has been given in the description of 
the Stanley layout, attention will be turned to the characteristics 
of the accessories offered by other makers. 

Doble. The details of construction of the Doble combustion 
chamber and boiler have already been shown in Figs. 35 and 41, and 
discussed on pages 34 and 40. The water level in the boiler is kept 
at the half-way point by an automatic by-pass valve, which is oper- 
ated by the expansion of a regulator tube. As the water rises in the 
boiler, the tube is filled from an outside pipe with comparatively cold 
water. The decided change of temperature causes the tube to 
contract again, and the water is by-passed to the supply tank. The 
steam pressure is maintained around GOO pounds by another automatic 
device, which controls the fuel system. 

From the upper headers of the generator sections, the live steam 
passes into a manifold which leads it through the throttle valve and 
then to the engine. From the engine, it passes back to the condenser, 
being forced along by the following steam. 

A non-rusting alloy is used for the seats of the throttle valve. 
The valve, shown in Figs. 28 and 29, is a compound design, being a 
combination of a poppet and piston valve. The piston portion regu- 
lates the flow of steam, while the poppet serves to keep the valve in a 
tight, or non-leaking, condition. 

The force of the steam constantly coming from the engine causes 
the steam to pass from the top to the bottom of the radiator condenser 



and, under normal conditions, the steam has been completely con- 
densed to water before it reaches the bottom. This water of conden- 
sation enters the water tank very near the bottom, so that any steam 
which still remains will be condensed as it bubbles up through the 
tank. Rapid acceleration from a slow speed or very hard slow pulling 
are the two conditions under which some steam may remain uncon- 
densed in passing through the radiator. As a safety measure, in case 
of a very long stretch of slow heavy pulling, the? water tank is pro- 
vided with a vent at the top. With this condensing system, it is said 
that a car will run 1500 miles on one filling of water. 

Doble Lubrication. Another one of Doble's departures from 
standard steam-automobile practice is in the matter of lubrication. 
The throttle, engine valves, cylinder walls, water pumps, and interior 
of the generator are all lubricated by regular gasoline-engine oil 
instead of the heavy steam-cylinder oil used in power plants. 

This .comparatively light mineral oil at once forms an emulsion 
with the water, due to the shaking up from the roughness of the road 
and the agitation of the feed water as the condensation enters the tank 
from the radiator. The oil, therefore, is sent into the generator along 
with the feed water and gives the interior of the tubes a very thin 
coating of lubricant. How thin this is may be judged by the state- 
ment that the generator temperature is 485° F. at the working pres- 
sure of 600 pounds. This coating not only prevents the tubes from 
rusting, but keeps scale from forming as it cannot stick to a greasy 
surface. The oil in the water also prevents scale from forming in other 
places and pipes, for it coats each particle of lime, etc., which may be 
thrown down and keeps it from sticking to any other particle and 
building up a deposit. It is this same oil that is carried over with 
the steam that lubricates the throttle valve and cylinder parts. The 
condenser saves the oil supply as well as the water, so that the lubri- 
cant is used over and over again, and a car is said to run 8000 miles 
on one gallon of oil. 

Steaming Test. One of the main features claimed for the Doble 
design is the short length of time required to raise steam to a working 
pressure, that for ordinary running being 600 pounds per square inch. 
The following test was recently given out by the company. > 

The generator had approximately 150 square feet of surface and 
contained, when the water was at its normal level, 8J gallons. Com- 





hustion started with the water in the generator at 00° F. 
trace of steam came in forty seconds. . 

The first 

lb por sq. in. 

Elapsed Time 


40 sec. 


1 min., 20 sec. 


1 min., 45 sec. 


2 min., 10 sec. 


2 min., 25 sec. 


2 min., 40 sec. 


2 min., 50 sec. 

lb. por »q. in. 







Of eld t. Fuel, Water, and Steam Connections. Fig. 54 gives a 
dear idea of the fuel, water, and steam connections of the Of eld t 

Fig. 64. Diagram of Connections for Ofeldt Boiler Feed and Fuel Systems 
Couriuy of F. W. Ofeldt & Sons, Nyaek-on-the-Uudeon, New York 

system, the burner and boiler of which have been described pre- 
viously. The feed-water pump A and the fuel pump e are usually 
on opposite crossheads of the engine, but to make the two systems 
clearer they have been separated in the diagram. 

The Ofeldt Company makes these accessories either for use as a 
complete system, as shown in the diagram, or for use with other 
units. The company does not make a complete automobile. 


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An expansion tube A T is the basis of the Ofeldt water regulator. 
This tube stands at right angles to the middle point of the boiler 
water column P, and when the water becomes low enough in the 
boiler and column for the tube to fill with steam, the expansion causes 
the closing of the water by-pass valve through the movement of the 
linkage 0, M, L. When used with the Ofeldt water-tube boiler it is 
claimed that a water-level glass is unnecessary. 

Fuel regulation is accomplished by the diaphragm valve, w. 
This is made up of two concave discs with a steel diaphragm fastened 
between them. Combined with the upper disc is the valve controlling 
the fuel supply. When the steam pressure on the lower side reaches 
the point for which the valve has been adjusted, the diaphragm pushes 
upward, shutting off the fuel. Upon the decrease of the steam pres- 
sure, the natural spring of the diaphragm again opens the fuel valve. 
Where used w r ith a pilot light the closing of the valve completely 
shuts off the fuel to the main burner, but where no pilot is used just 
enough fuel is allowed to pass to keep the fire burning. 

Automatic Fuel Feed. Possibly the most interesting * of the 
Ofeldt accessories is the automatic fuel feed i, in which a spring is 
used to keep the fuel under pressure. It consists of a brass cylinder, 
18 to 36 inches long and 4 inches in diameter, which is plugged at one 
end and capped at the other. Running the length of the cylinder is a 
coil spring w r ith a piston at one end. The engine fuel pump e, or 
hand pump d, forces the fuel into the tank, pushing back the piston 
and compressing the spring. This spring keeps the pressure on the 
fuel the same as is done by the air tanks in the Stanley system. As 
part of the pressure layout is a safety or by-pass valve J, which can 
be set for the desired pressure on the fuei, the excess fuel from the 
by-pass valve and from the leakage past the piston in the regulator 
are returned to the fuel tank. 


In the preceding description considerable has been said as to 
the management and care of the units, but in this section some 
further hints will be added on the operation of steam automobiles. 

Management on the Road. As will be understood from the fore- 
going, the operator's part in managing the power plant — other than 
attention to the throttle — is ordinarily limited to watching the water- 


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level indicator and managing the by-pass valve — if not automatic — 
in accordance with the water level. When the level drops, the 
by-pass valve must be closed, thereby causing all the water pumped 
to enter the boiler. When the water level exceeds the proper height, 
the by-pass valve is opened and water ceases to enter the boiler. 
It is not practicable to open the by-pass valve part way, as this would 
cause the water to go through the valve at boiler pressure and, in 
time, the scouring action due to the pressure would make the valve 

Blind adherence to the above rule will not always give as good 
results as may be obtained through manipulation. For example, if 
one sees a hill ahead, he can fill the boiler somewhat higher than its 
usual level and give the added water time to get hot before the hill is 
reached. This affords a reserve supply for surmounting the hill. In 
the average hilly country, one can make a practice of pumping water 
on down grades when little or no steam is being used and the heat of 
the fire is available to heat the incoming water. Near the bottom of 
the hill the by-pass valve is opened and the ascent taken in good 
style. If the accumulated pressure has caused the fire to shut off, the 
throttle may be opened just before the bottom of the hill is reached, 
and the drop in pressure will bring the fire on while impetus is being 
gained. It is a general rule for all classes of steam cars that the fire 
should, if possible, be "on" before an up grade is begun. By proper 
management the fire may be kept burning continuously in a hilly 
country, while power is used only on the up-grades. 

In applying the above principles it should be remembered that 
only the wetted inside surface of the boiler is available for making 
steam. If the water is low, steam cannot be raised as rapidly as 
when the boiler is full, assuming that the water is hot in both cases. 
On the other hand, if the boiler is worked too full one may get wet 
steam despite the superheater, with loss of power due to condensa- 
tion. In an extreme case, enough water might even be carried through 
to choke the clearance spaces at the cylinder ends. This would 
probably result in a head being knocked out or a connecting rod or 
crank bent, as the water could not be ejected quickly enough by the 
lifting of the slide valve to save the engine from severe shock when 
the piston reached the end of its stroke. A boiler of the Lane type, 
in which the water is partly converted into steam in coils above the 



boiler proper, and in which the fire tubes are large enough to permit 
combustion to take place inside of them, is an exception to the above, 
in that superheating takes place chiefly in the "boiler". 

The more rapidly fuel is supplied to the burner, the hotter will 
be the fire. Where ample power is desired, therefore, the burner 
is worked under more than ordinary pressure. In the Stanley cars, 
which carry pressure only in the auxiliary tank, 120 to 140 pounds is 

Firing-Up. The following remarks apply particularly to cars 
with the Stanley type of burner and boiler. In the case of the Doble 
car, the constructions are so different that many of the instructions 
will not apply. The Doble system has been described in detail in the 
preceding pages, and the reader is referred back to these paragraphs 
for the firing-up of the boiler, etc. As will be explained later, it is 
customary at the end of a run to blow down the boiler for the purpose 
of ridding it of whatever sediment may be present. The blow-off 
valve is shut when a few pounds of pressure still remain, and the con- 
densation of this remaining steam should suck the boiler full of water, 
provided the by-pass valve is closed. The presence of this water is 
desirable to protect the superheating coil when the fire is started. 
Therefore, if the car has a conventional fire-tube boiler with super- 
heating coil beneath, the first step is to ascertain whether the boiler 
is actually full. Close the by-pass (if open), open the upper try cock, 
and if no water comes out, work the hand pump. See that the water 
tank is full. Open the throttle and the drip valve on the steam chest 
and continue pumping by hand till water comes out. Leave them 
open while starting the fire, to allow the water to expand. 

If there is no pressure in the fuel tank, pump it up to the mini- 
mum working pressure by hand. Heat the pilot, either by burning 
gasoline in a cup, by an alcohol wick, or by the modern acetylene 
torch, as the case may be. When thoroughly heated, slowly open 
the pilot-light supply valve. If a blue flame does not result, close the 
supply valve and admit more gasoline to the cup. 

After starting the pilot light, allow it to burn till the vaporizer 
is hot, then open the main-burner valve carefully. If it fires back 
into the burner, shut it off, wait a minute or two and try again. 
Turn the burner to full height gradually. If the flame is yellow 
or smoky, it is not getting enough air; if it is noisy and lifts off the 




burner, it is getting too much air. Once adjusted for a given fuel 
pressure, the nozzle or air shutter should not need changing. 

While the water is getting hot, the oiling up can be attended to. 
As soon as the pressure begins to rise, water will issue from the drip 
cock on the steam chest. Close this cock and the throttle valve as 
soon as clear steam comes out. 

When pressure reaches 100 or 200 pounds, get into the car, throw 
the reverse lever to its full forward or backward position, open the 
throttle slightly and then close it at once. Repeat till the engine 
starts. With some yards of clear way, work the reverse lever back and 
forth with the throttle open only a crack, so that the car "seesaws" 
slowly. This will work the water out of the engine and warm up the 
cylinders till the entering steam ceases to condense. This process 
must not be hurried. An attempt to cut it short is likely to result in 
damage to the engine. As long as water is present the engine will 
run jerkily. When it runs smoothly the car is ready to start. 

On starting, the first few blocks should be run slowly to com- 
plete the warming-up process. If the air pressure is below normal 
the air pump should be kept going. 

At the End of a Run. On finishing a run, the boiler should be 
blown down with the fire turned off. This should be done by open- 
ing the blow-off valve near the bottom of the boiler. The escaping 
water will carry with it all the mud and precipitate that have accumu- 
lated. Close the blow-off valve at about 100 pounds, and the sub- 
sequent condensation will fill the boiler by suction from the tank. 
If the water in the tank is covered with oil, the end of a hose should* 
be inserted and the tank flushed out to get rid of the oil. It is a good 
plan to put a cupful of kerosene into the tank. It will not only 
loosen whatever oil may be clinging there, but will help loosen the 
scale liable to forjn from hard water. 

A thermostat water-level indicator operates only when steam 
is up. When the boiler is cold it indicates high water whether water 
is present or not. When the car is running, a faulty reading of the 
water level is usually soon noticed, and if it is overlooked there is 
still protection of the fusible plug. If, however, the boiler should 
be fired up with no water in it, the fusible plug would melt without 
the fact being heralded by escaping steam. Therefore, the fusible 
plug, like the water-level indicator, is useful only when steam is up. 



i Engine Lubrication. For the older cars not using superheated 
steam, the regular power-plant steam-cylinder oil is usually recom- 
mended. This is a mineral oil mixed with tallow to make it hold on 
the wet cylinder walls. It often contains graphite. This type of oil 
will not stand the high temperatures of superheated steam, and special 
oils must be used. As an example, the Stanley Company has recom- 
mended either* 'Harris superheat steam-cylinder oil" or "Oilzum high- 
pressure superheated steam-cylinder oil". The Doble uses the same 
kind of gasoline-engine oil as is used by the ordinary motor-car driver. 
Other engines use different grades of oil to the best advantage, and it 
is best in each case to find out the maker's recommendations. 

The Fusible Plug. If the fusible plug blows out when the car 
is running, the escape of steam may be shut off by closing a valve 
usually interposed between the boiler and the plug. The fire should 
be shut off at once and, if possible, the car should be run to reduce the 
pressure, thereby allowing the boiler to cool somewhat. When the 
drop in pressure compels a halt, close the by-pass valve and pump 
water in by hand till it shows in the lowest try cock. Then, after 
replacing the fusible plug, the fire may be relighted and the water 
level restored while the car runs. 

If the plug blows simply because the by-pass valve has been 
open too long, the by-pass can be closed, the main fire shut off, and 
the engine run by jacking up the rear wheels, till water shows in 
the lowest try cock. 

Causes of Low Pressure. Low pressure is generally due to 
insufficient fire. If the burner pressure is low, steam will not be made 
rapidly. If the burner pressure is all right, the burner nozzle may 
be clogged or the vaporizing tube may be choked with carbon. The 
nozzle may usually be poked out with a bent wire without turning off 
the fire. If, however, the vaporizer is clogged it will have to be 
removed when the car is cold and cleaned, with a drill or otherwise, 
as the makers direct. 

Occasionally the valve controlled by the diaphragm regulator 
may be choked, and rarely the main-burner valve. Either can be 
cleaned by disconnecting and running a wire through. 

Occasionally the pilot light may clog in the same way, usually 
at the nozzle. The remedy is the same as for the main burner. 

If the air pump fails to raise the pressure on the fuel tank to 


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the required degree, it is probable that the intake or outlet check 
valves leak. If, as is likely, they have oil on them, the oil may have 
gathered dust. The valves should be taken out and cleaned, and a 
drop of oil put on them to make them tight. 

The various packings about the engine and auxiliaries require 
occasional tightening, and once in a while new packing is necessary. 
If the new packing is soft, like wicking, it may be put on top of thfe 
old, otherwise the old must be removed. The packing should not 
in any case be tighter than necessary to prevent leakage, for unnec- 
essary friction would thereby be caused. A slight leakage about the 
water and air pumps may be permitted to save friction. As the hand 
pumps are rarely used their packings can be looser than those of the 
power pumps. 

Scale Prevention and Remedies. In. sections where hard water 
is used, the subject of scale is a serious one, and its treatment will 
depend on the character of the mineral contained in the water. Fre- 
quently it is possible to precipitate the mineral before putting the 
water into the tank. Sometimes the addition of a small quantity of 
lime will do this, sometimes carbonate of soda or "soda ash". Still 
other waters are successfully treated by adding caustic soda. Some- 
times the simple addition of kerosene to untreated water will loosen 
the scale as above indicated. If these remedies are not successful, 
the user is advised to send a sample gallon of water to a maker of 
boiler compounds and have it analyzed, after which a suitable com- 
pound can be recommended. Scale allowed to accumulate by neg- 
lect is not only very detrimental to the boiler by interfering with the 
free flow of heat, but it also seriously reduces the steaming power. 
Instances have been known of the steaming capacity of boilers being 
reduced fifty per cent or more by scale. At the same time the shell 
and tubes get hotter than they should, resulting in unequal expansion 
and leakage. 

Filling the Boiler. Before firing up, be sure that the boiler and 
superheaters are full. To be sure of this, open the throttle valve and 
steam-chest drip, close the by-pass valve and work the hand pump 
until water comes from the steam-chest drip. If more convenient 
fill the boiler from the town supply by means of the coupling fur- 
nished for this purpose, connecting to the blow-off valve. Never 
light the fire until you arc sure that the boiler is full. 



At the end of a run open the blow-off valve 'at the front of the 
boiler, and blow down to about 100 pounds. Fill the water tank and 
close the by-pass valve, and the condensing steam in the boiler will 
siphon the boiler full. Before blowing down; see that the pilot light 
is out, as well as the main burner. It can be extinguished by blowing 
into the pilot mixing tube. 

Raising Gasoline Pressure. If the pressure tanks are empty 
and the pressure zero, proceed as follows: 

Open the hand gasoline-pump valve and work the pump till 
the air gage registers 10 or 15 pounds. Tank 2, Fig. 47, is now full of 
gasoline, and tank 1 is full of compressed air. Attach the hand air 
pump to air valve and pump air into tank 1 till the gage indicates 
80 or 90 pounds, which is the working pressure for the burner. 

If now the fire is lighted and the car stands still, the pressure 
will gradually drop, but may be raised in a moment by working the 
hand gasoline pump. When the car runs, the power pump main- 
tains the supply. 

The air in tank 1 is gradually absorbed, and additional air is 
required. This is indicated, first, by the vibration of the air-pressure- 
gage needle when running; second, by a rapid drop of pressure when 
the car stands still. In case of doubt whether the drop is due to lack 
of air or to a leak in the automatic or pump valves, close the pressure- 
retaining valve. If the pressure still falls the air is insufficient. 

Occasionally empty the pressure tank by opening valve D, and 
refill in order to determine definitely the amount of gasoline in it. 

If the car is to stand some time with pilot burning, close the 
pressure-retaining valve to prevent the gasoline from leaking back 
through the valves and automatic. Be sure to open again on starting. 

General Lubrication. On page 60, are mentioned the different 
grades of oil suitable for cylinder lubrication in the various types of 
engines. The lubrication of the cylinder walls and valves, however, is 
not the end of the subject, for, wherever there are two moving surfaces 
in contact, there must be lubrication in order to keep the friction losses 
at a minimum. Useless friction in the running parts of the engine and 
chassis of the car means an increased consumption of fuel. This, 
however, is often of secondary consideration in comparison with the 
wear and resulting repair bills, often caused by lack of lubrication. 
When a bearing Ixronies dry, it usually heats up aud expands, and 




in case this is continued to the point of "freezing", the car may be 
completely disabled on the road. 

Of course all parts of the car do not have the same amount of 
motion and, therefore, do not require the same amount of lubrication. 
All makers of cars issue instruction books for each model and, when 
possible, the operator should provide himself with a copy and follow 
the oiling instructions. This, however, is often impossible, and it is 
then a matter of good judgment based on the known requirements of 
other cars. Outside of the power plant there is no particular differ- 
ence between the construction and care of a steam- and a gasoline- 
engine driven car, and the lubrication chart of any of the later makes 
can be safely followed. 

In the modern Stanley and Doble types, the crankshaft, cross- 
head, and other moving engine parts, other than piston, together with 
the rear-axle bearings, are all lubricated by splash, the crankcase being 
thoroughly oil-tight. The level of this oil should be inspected every 
two months, although it will probably not need renewing that often. 
Some of the older cars require that the eccentric be given a squirt 
of oil daily, by a hand gun. It is a good habit to give all grease cups 
a turn-down each day. 

Water Pump. If the water pump fails to work, first see if the 
tank is empty. In addition to this there are three other causes to 
which failure is mainly due, viz, (1) The pump may be air-bound. To 
rem edy, open the by-pass valve and run the engine. The air will work 
out readily, since there is no pressure against it. (2) The check valves 
may leak. There are three check valves, one on the pump intake, 
another on the outlet, and the third at the boiler. The intake valve 
is the most likely to leak. Remove the valve cap and clean the valve 
ball and its seat, being careful not to scratch them. If the boiler 
check valve is leaking, it will permit steam to escape into the water 
tank when the by-pass valve is open. This valve can only be exam- 
ined when there is no pressure. (3) The pump packing may leak. 
Tightening the packing nut generally suffices, but occasionally 
repacking is necessary. Do not screw the packing nut tighter than 
is necessary, as it causes needless friction; a slight leakage may be 
tolerated. In case the power pump fails, use the hand pump, first 
running with the main fire off till the pressure is reduced to about 100 
pounds. After pumping, close the valve with the pump plunger in. 

407 Digitized by 



Gasoline Pump. In most respects the gasoline pump resembles 
the water pump. If it becomes air-bound, it can be primed by using 
the hand gasoline pump, which is much larger and, drawing through 
the power pump, will suck out the air. 

The gasoline pump packing should not leak at all, as it is both 
wasteful and dangerous. The pump is so small that adjusting is 
seldom needed. 

If the hand gasoline pump becomes air-bound, unscrew the valve, 
which is open when the hand pump is used, till it comes out. Press 
the thumb over the valve-stem hole when the pump plunger is pulled 
out, and lift it off when the plunger is forced in. Repeating this 
several times will expel the air. 

If the hand gasoline pump and hand water pump work together, 
the packing nut on the gasoline pump should be just tight enough 
to hold the gasoline, and the water pump should have its packing 
so adjusted that the pump will run perfectly free. 

To pack the gasoline pump, put in first a thin leather washer, 
then three of the special packing rings supplied by the makers, then 
another thin leather washer, and screw the stuffing-box nut only 
hand tight. Do not use a tool to tighten it, otherwise the plunger 
will cut out the packing. 

Care of Engine Bearings. If the engine is regularly lubricated 
the bearings will seldom require adjustment. If the bearings show 
the slightest discoloration from rust they have been insufficiently 
oiled. Adjustments are made as follows: 

The crosshead guides are taken up by screwing down the nut 
on the bolt holding the frame rods together. The crosshead balls 
must be under sufficient pressure to keep them from slipping. 

The wrist pins are taper and are adjusted with a screw held by 
a lock nut. First loosen the lock nut, turn up the screw till it stops, 
then back it one-eighth turn and tighten the lock nut. 

The crankpin ball bearings are adjusted by removing the 
bolt, taking out the plug, and reducing it slightly by filing. When 
correctly adjusted the bearings should have no perceptible play. 

The main bearings and eccentrics can only be adjusted after 
the engine is taken out of the car. They are adjusted to take up lost 
motion by filing or grinding down the face of the bearing cap, which 
must be very carefully done. 


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Be sure the engine-frame hangers are properly adjusted.. Should 
the nuts work loose, the front end of the engine will sway, to the 
damage of the engine case and gears. In adjusting the engine-frame 
hangers do not set them up so tight that they will not swivel around 
the rear axle. If necessary insert shims of paper or thin brass, 
removing the rear engine case to gain access. 

Operating the Cut-Off and Reverse. In the more recent Stanley 
cars the cut-off is variable from one-quarter to one-half stroke. On 
the engine is a quadrant from which the reverse lever works in con- 
nection with the reverse pedal. The quadrant has one notch, into 
which a dog attached to the reverse lever drops when the engine is 
"hooked up", that is, operating on short cut-off. To hook up the 
engine, press on the reverse pedal only. To release the dog, press a 
pedal beside the reverse pedal, called the clvich pedal. This releases 
the reverse pedal and a spring pulls it back, allowing the engine to cut- 
off at half-stroke. The car should always be started with the reverse 
pedal released, and the cut-off should not be shortened until the 
engine attains good speed. If it operates jerkily, release the reverse 
pedal by pressing the clutch pedal. 

Care of the Burner. If the car does not steam well, look at the 
fire first. See that the gasoline pressure is not below 100 pounds. 

If the pressure is right, the gasoline line may be clogged in the 
automatic valve, vaporizer, burner nozzle, or main-burner valve. 
If the burner has two mixing tubes, see if both sides are affected; 
if so, the trouble is probably in the automatic valve. If the two 
burner flames are unequal, the trouble may be in the vaporizing 
tubes or the nozzle, more likely the latter. Clean the nozzles by run- 
ning a small wire through them with the screw out, or by using a bent 
wire without removing the screw. 

If the vaporizing tubes are clogged, uncouple at the back of 
the burner, take out the bundle of wires from the tubes, and clean 
the tubes and wires thoroughly, using the bundle as a swab. Extin- 
guish all fire before beginning. 

If the pilot-light nozzle becomes clogged, use a screwdriver 
to turn the horizontal nozzle screw back and forth. A wire projects 
from this screw through the nozzle orifice and turning the screw 
causes the wire to clean the nozzle. Do this only with the pilot 


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To regulate the air received by the pilot, bend the pilot vaporizer 
tube slightly away from the mixing tube for more air, or inward for 
less air. The pilot should burn with a blue flame slightly tinged 
with yellow, and may be adjusted while lighted. 

Never use a reamer for cleaning either the pilot or main-burner 
nozzle, as it is likely to enlarge the hole, which is that of a No. 62 drill. 

Sometimes after the automatic valve closes, the gas pressure 
at the nozzles will reduce gradually, causing the burner to light- 
back. When next the automatic valve opens, the fire will burn inside 
the mixing tubes with a roaring sound. This sound should be the 
instant signal for closing the main-burner valve and allowing the 
mixing tube to cool. 

If the burner should fire back frequently and with a sharp 
explosion, it would indicate either a leak in the burner or a leak of 
steam in the combustion space. To test for a steam leak, first get 
up steam pressure, then take off the burner and examine the boiler, 
then run the front wheels against something immovable and open 
the throttle valve to see if steam escapes from the superheaters. 

To Adjust the Throttle. If the throttle valve leaks it must be 
reground or a new valve substituted. It may, however, appear 
to leak owing to improper adjustment. There should be some 
tension on the valve stem when the lever is locked in the closed 
position. There is a distance rod running from the body of the 
throttle valve through the dashboard close to the throttle-valve 
stem. To increase the tension on the throttle, adjust the nuts on the 
distance rod. 

To Adjust the Automatics. To carry a higher steam pressure, 
screw the adjusting screw on the automatic vfdve further in; for a 
lower pressure, screw it out. The same regulation of the gasoline 
relief valve will produce similar variations of the fuel pressure. 

To Lay Up for the Winter. Run the car, on the road or with 
the rear wheels jacked up, till everything is hot, then extinguish the 
fire and blow off the boiler. While steam is escaping, open the 
safety and siphon valves and take out the fusible plug to clear them 
of water. Empty the tank, take off the caps of the check valves, 
and blow into the suction holes to clear the water from the checks 
ahead. Take off the water indicator and empty it, unless it is filled 
with non-freezing mixture. 


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General Remarks on Operating. The commonest fault of 
Stanley operators is opening the throttle too abruptly on starting. 
This is bad enough if the cylinders happen to be clear of water; 
\t they are not clear, the results may be destructive. Always start 
slowly, and do not come up to road speed till the engine runs 

Never open any of the valves more than two or three full turns. 
They are screw valves, and if turned a dozen or more times they 
will come clear out. 

Practice reversing where you have plenty of room. The ability 
to look and steer backward while operating the reverse pedal and 
throttle is not a natural gift. After reversing, be sure that the pedal 
has been released, by pressing the clutch pedal before giving steam. 


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1. Name two methods of welding heavy sheet steel and describe 
one of them. 

2. Qive the characteristics of the low-pressure acetylene gene- 

3. Name and describe the characteristics of the three types of 
blowpipe flames. 

4. What kind of welding rod and what flux are used in welding 

5. In what essentials does the cutting blowpipe differ from the 
welding blowpipe? 

6. Give the method of measuring the oxygen used in a welding 

7. Describe the essentials of an electric welding outfit. 

8. Draw a simple diagram showing the essential parts of an 
acetylene welding outfit and their location. 

9. Describe the process of welding up a hole which has been 
accidentally made in the work. 

10. Why is pre-heating important? 

11. Give the important distinctions between the treatment of 
steel, cast iron, aluminum, and copper during the welding process. 

12. What is the action of the acetylene regulator? 

13. Give the various steps in butt-welding a pair of steel plates, 
showing how to manipulate the blowpipe. 

14. What are the principal factors in the production of defective 
welds and what can be done to avoid them? 


Digitized by 





1. Explain the process of scraping a crankshaft bearing. 

2. What tap and die equipment should be found in a good 
automobile repair shop? 

3. Give the most important parts of a lathe and the accessories 
necessary for ordinary shop operations. 

4. What other machines besides the lathe are useful or necessary 
in a repair shop? 

5. Give the process of mounting a clutch leather. 

6. Describe how a cylinder is lapped by means of a jig in a drill 

7. Give the principle of action of a micrometer caliper and show 
the uses to which .the instrument may be put. 

8. Give the names of the different kinds of files used in repair 

9. How are piston rings fitted and put in place on the piston? 

10. What fluxes are used in soldering the various common metals 
in the repair shop? 

11. How would you cut a keyseat in a piece of round steel 

12. Give the number of flutes advisable on a reamer and state 
your reasons. 

13. Give a diagram showing how to calculate the setting for the 
graduated circle on the lathe slide rest to produce a given taper. 





1. What power machines are most necessary for an automobile 
repair shop and what are the uses of these machines? 

2. Explain the basis of calculation of a garage proposition as 
an investment. 

3. Analyze the revenue from all sources for a garage holding, 
say, 100 cars. 

4. Give a good layout for a'one-story garage, size 75 by 200 feet, 
giving the location of necessary equipment and the most efficient 
arrangement of cars. 

5. What building equipment is necessary in a 3-story garage t 

6. Discuss elevators vs. ramps. 

7. Under what circumstances is a garage justified in carrying 
accessories and selling cars? 

8. Explain how a garage owner is going to settle the question 
of exclusive storage of cars, as compared with part storage space and 
part sales space. Give figures to justify conclusions. 

9. Give the points necessary to consider in determining a good 
location for a garage. 

10. Is the square shape of building economical for a garage? 
Explain, and give the best arrangement for a square floor plan. 

11. What is the best use to which a basement in a garage can 
be put? 

12. Give a sketch showing a safe arrangement for the gasoline 

13. What should be the specifications for a garage as to fire* 






1. How many cylinders has the conventional American 
motorcycle, and what type motor is usually used? 

2. In what way has the installation of high-speed motors 
influenced the design of motorcycles? 

3. Give a complete description of the Smith motor wheel. 

4. What is a cyclemotor? 

5. Give specifications for the engine used in the Excelsior No. 9. 

6. What American companies manufacture 4-cylinder motor- 

7. Give complete specifications for the engine used in the 
Henderson motorcycle. 

8. What is the difference between a 4-cycle and a 2-cycle 

9. Describe the spring frame construction used in the Merkel. 

10. What two main types of frames are used in motorcycle 

11. How are the crankshafts fitted on flywheels in 5-cy Under 

12. Describe the action of the Indian roller-cam oil pump. 

13. What type of transmission is used in the Harley-Davidson? 

14. Describe the principle of operation of the Midco magneto- 
generator as used on the Excelsior. 

15. Describ * the Harley-Davidson commercial van. 





1. Define radiation, absorption, conduction, and convection. 

2. What is absolute zero? What molecular state does it 
theoretically represent? 

3. Discuss the location of the steam engine on automobiles. 

4. Convert 65 degrees Fahrenheit into centigrade. 

5. State Boyle's Law. 

6. Define force, work, power, and horsepower. 

7. Describe and sketch the action of an elementary slide 

8. Define British thermal unit. 

9. Draw a theoretical indicator card for one-fourth cut-off. 

10. Define latent heat. How many British thermal units are 
absorbed in boiling away a pound of water at atmospheric pressure? 

11. Discuss the effect of compression on the indicator card of 
an engine. 

12. Why is the explosion of a stationary boiler so destructive? 

13. Define superheat. What is its object? 

14. What is the purpose of condensers if used on steam cars? 

15. Describe and sketch the Stephenson link valve motion. 

16. Describe the Bunsen burner. 

17. What is the object of the pilot light? 

18. Describe the Ofeldt burner. 

19. How are automobile boilers classified? 

20. Explain the principles of the fire-tube boiler. 

21. In what way do flash boilers differ from the other types? 

22. For what purpose are check valves used; how are they 





Digitized by 


Digitized by 



The page numbers of this volume will be found at the bottom of the pages; the 
numbers at the top refer only to the section. 


Absorption of heat 350 
Acetylene consumption, measuring 1 1 2 

Acetylene generators 15 

Acetylene regulator 30 

Addendum circle 169 
Air leaks in inlet manifold of 

motorcycle 333 

Air-supply system for public 

garages 254 

Aluminum castings 81 

Aluminum welding 78 

cast aluminum 81 

general considerations 78 

sheet aluminum 79 

Ammeter 317 

Annealing 55 

Arbor presses 173 

types 173 

uses 175 

Arc welder 22 

apparatus 23 

graphite electrode 23 

metallic electrode 23 

Architectural appearance of public 

garage 239 

Arrangement of cars in public 

garage 202 

Automatic switches 313 

Automobile boilers for steam cars 380 

fire-tube boilers 380 

flash boilers 385 

special types 387 

water-tube boilers 382 

Automobile repair shops 

accurate filing in 123 

draw filing 124 

Note. — For page numbers see foot of page». 

Automobile repair shops (contin- 
accurate filing in 

filing to micrometer fit 124 

revolving filing . 125 

use of safe edges 123 

welding in .11 

Automobile repair by welding, 

examples of 97 

axle housings 104 

bodies and fenders 100 
crankcases and transmission 

cases 107 

engine cylinders 105 

frames 97 

manifolds 104 

pressed-steel parts 97 

shafts and axles 103 

springs 102 
Automobile welding, miscellaneous 

processes in 8G 
carbon removing by use of 

oxygen 95 

cutting 86 

examples of automobile repair 97 

lead burning 91 

Auto-Ped motorcycle 280 

Axle housings, repair by welding 104 



Babbitt, pouring 


Bearing scraping i^o 

bearing scrapers from old files 132 
cleaning and fitting connecting- 
rod bearings 







Digitized by 



Bearing scraping (continued) 

holding crankshaft 128 

Bearings, rebabbitting 126 

Bench methods in repair shop 172 

avoiding scale 173 

drilling hard metals 173 

peening 172 

pickling 173 

Bench work 115 

bearing scraping ' 128 

chipping and filing 117 

cutting gears 168 

drilling 144 

fitting piston rings 135 

fitting taper pins 155 

forging 163 

hand keyseating 156 

lapping cylinders 141 

miscellaneous bench methods 172 

reaming 151 

rebabbitting bearings 126 

riveting 158 

soldering 133 

tapping 147 

use of micrometers 139 

work bench design 115 

Blacksmithing repair outfit 164 


description 17, 26 

method of lighting 33, 89 

position of in welding 37 

Blow torch 134 

Bodies and fenders, repair by 

welding 100 
Boiler accessories and regulation 

in steam cars 388 

check valves 388 

Doble 397 

fuel system 388 

Ofeldt 399 
Stanley fuel, water, and steam 

systems 389 
Boiler and engine types in steam 

automobile 348 

Boiler explosions, cause of 357 

Boyle's law 352 

Brake linings 158 

Note. — For page numbers see foot of paQe*. 

Brake linings (continued) 

riveting lining 158 

types of rivets 158 

Brakes, motorcycle 305 

Brass and bronze welding 84 

Brazing malleable iron 78 

British thermal unit 354 

Brushes, care of 342 

Building materials for public 

garages 237 

availability 238 

fireproofness 238 

first cost 237 

Bunsen burner 375 

Burner principles 375 

Burners for steam cars 374, 409 

burner principles 375 

care of 409 

pilot light 376 

types of burners 376 

Burning hole in metal in welding 41 

how to weld up hole 41 

Carbon burning 96 

Carbon-removing apparatus 96 

Carbon removing by use of oxygen 95 

burning out carbon 96 

old process of removing carbon 95 

Carbonizing flame 36 

Carburetor, motorcycle 327, 332 

Cast-aluminum welding 81 

after-treatment 82 

aluminum castings 81 

pre-heating 81 

preparation 81 

welding process 81 

Cast-iron welding 69 

expansion and contraction 70 

flux 71 

general considerations 69 

oxidation 69 

pre-heating 70 

preparation of welds 72 

welding process 73 

welding rods 70 

Check valves 388 


Digitized by 



Chipping in automobile repair 

117, 156 

chipping 119, 156 

chisels 117 

chisel types 118 

Chisel types used in repair work 118 

cape 119 

diamond point 119 

flat 118 

round nose 119 

Circular pitch of gear 169 

Clearances in reamer teeth 153 

Clutch facings 159 

preparing leather 159 

proper clutch leathers 159 

putting leather on clutch 159 

riveting process 159 

Clutches, motorcycle 308, 339 

oily 339 

Coefficient of expansion 46 

Cold-riveting metals 160 

Compound expansion 364 

Compression, effect of on indicator 

card 362 

Conduction 350 
Connecting-rod bearings, cleaning 

and fitting 129 
cleaning parts 129 
cut ting-in bearing 130 
filing shims 130 
putting lampblack on crank- 
shaft 129 
scraping process 130 
Construction details of motor- 
cycles 293 
brakes 305 
clutches 308 
drive 306 
electrical equipment 311 
gearsets, or change-speed mech- 
anisms 309 
lubrication 303 
motors 295 
regulation 315 
spring and frame construction 293 
starting 305 
storage batteries 318 

Note. — For page number* see foot of pages. 

Contraction in welding 

18, 46, 47, 49, 56, 63, 70, 78 

Control, motorcycle 329 

Convection 350 

Copper welding 82 

after-treatment 84 

general considerations 82 . 

preparation 83 

welding 83 

Crankcases and transmission cases, 

repair by welding 107 
Crankshaft, holding upright on 

bench 128 
Cut-off, operating on steam cars 409 
Cutting in automobile repairs 86 
back-firing 90 
care of apparatus 89 
cutting blowpipe 88 
how to light blowpipe 89 
• instructions for connecting ap- 
paratus 89 
necessary cutting apparatus 88 
notes on cutting 91 
principle of cutting with oxygen 87 
regulators 89 
to shut off blowpipe 90 
Cutting blowpipe 88 
care of blowpipe 89 
cutting nozzle 88 
working pressure' 89 
Cutting gears in repair work 168 
definition of terms 168 
addendum circle 169 
dedendum circle 169 
face 169 
flank 169 
pitch 169 
pitch diameter 169 
space 169 
thickness 169 
method of design 169 
Cutting with oxygen, principle of 87 
Cyclemotor 278 
Cylinder, cleaning after grinding 144 


Dayton motorcycle 



Digitized by 




Dedendum circle 169 

Defects in welds 42 

adhesion of added metal 43 

failure to penetrate 43 

improper flame adjustment 42 

insufficient reinforcing 44 

Designs of public garages 207 

large size garage 218 

medium size garage 212 

small size garage 207 

very large garage 227 

Dies in repair work 150 

Dirty motorcycle muffler 341 

Dismounting motor 128 

Doble steam car 370, 397 

lubrication 398 

steaming test 398 

Drainage of public garages 250 

Draw filing 124 

Drill presses 180, 262 

function 180 

lubrication in drilling 182 

method of action 181 

securing work 182 

Drilling hard metals 173 

Drilling in modern repair shop 144 

grinding drills 146 

lubrication 147 

sizes of drills 146 

speed of drills 147 

types of drills 144 

Drive, motorcycle 306 

belt drive 306 

chain drive 307 

shaft drive 307 


Early cut off, effect of 363 

Early motorcycles 271 

Electric or gas furnaces 164 

Electric welding processes 21 

arc welder 22 

methods 21 

spot-welder 21 

Electrical equipment, motorcycle 311 

automatic switches 313 

Note. — For page numbers tee fmA of pages. 

Electrical equipment, motorcycle 
development from battery cur- 
rent 31 1 
magneto generators 313 
Electrical troubles 342 
care of brushes 342 
lubrication of electrical equip- 
ment requires care 342 
short-circuits and open circuits 342 
storage batteries 342 
Elevators vs. ramps for large size 

garage 218 

Emery wheel 262 

Engine bearings, care of 408 

Engine cylinders, welding 105 

protection for machined sur- 
faces 106 
testing welded cylinders 107 
Engine lubrication for steam car 404 
Engine operation, principles of in 

motorcycle 289 

classification 289 

four-cycle motor 289 

two-cycle motor 291 

Engine types and details on steam 

cars 369 

Doble 370 

National 373 

Stanley 369 

Engines, motorcycle 295 

European high-speed motorcycle 

engine 301 

Expansion and contraction in 


18, 46, 47, 49, 56, 63, 70, 78 

Exterior design for public garage 237 

architectural appearance 239 

building materials 237 

ease of erection a factor 239 

general suitability of design 244 

typical designs 240 

Filing methods in automobile re- 
pair 119 
accurate filing 123 


Digitized by 



Filing methods in automobile re- 
pair (continued) 

cleaning files 125 

file shapes 120 

manipulation of files 121 

presence of grease 126 

proper files for certain work 120 

types of files 119 

uses of different shapes of files 123 
Finances and building costs of 

public garages 232 

income and expense estimates 232 
Financial problems of public 

garage • 199 
Finish filing 157 
Fire-tube boilers 380 
fusible plug 381 
Stanley 380 
Firing-up 402 
Flame, welding 79 
Flash boilers 385 
Flat drills 144 
Flux for welding 19, 71 
Forging , 163 
blacksmithing repair outfit 164 
electric or gas furnaces 164 
equipment 163 
heat treatment 165 
Four-cycle motorcycle engine 289 
Four-cylinder motorcycle engine 300 
Frame construction, motorcycle 293 
Frames, repair by welding 97 
Front stand attachment for motor- 
cycle 325 
Fuel system of steam car 388 
Fuels, heat values of 354 
Fuels for public garages 252 
Fuels for steam cars 374 
gasoline and kerosene 374 
Fuses 318 
Fusible plug 404 


Garage furniture 255 

Garage tools 260 

hand tools 260 

machine tools 261 

Note. — For page number* see foot of pages. 

Garage tools (continued) 

tool equipment for larger shops 265 
Garages, public 197-266 
Gas furnaces 164 
Gases, laws of 352 
behavior with changes of tem- 
perature 353 
Boyle's law 352 
Gases used in oxy-acetylene pro- 
cess 13 
Gasoline as fuel for steam car 374 
Gasoline pump 408 
Gear pullers 176 
cutting 89 
definition of terms 168 
method of design 169 
Gearsets, motorcycle 309 
one-speed 309 
three-speed 310 
two-speed 310 
two-speed planetary 309 
Generators, acetylene 15 
low-pressure 15 
pressure generator 16 
Grinders 177, 262 
advantages of grinding 177 
care of tools 179 
types of grinding 177 
Grinding drills in repair shop 146 
Grinding in lathe 264 

H , 

Hack saws, power 182, 262 

Hammering 56, 69 

Hand keyseating in repair shop 156 

finish filing 157 

keyseating process 156 

laying out keyway 156 

Woodruff keys 158 

Hand tools for public garages 260 

Hardening steel 166 

Heat transformation 354 

Heat transmission 349 

conduction 350 

convection ^- 350 

expansion 350 


Digitized by 




Heat transmission (continued) 

radiation and absorption 350 

relative conductivity 350 

temperature scales 351 

Heat treatment in automobile * 

repair 165 

bending rods 168 

hardening high-speed steel 167 

hardening steel 166 

self-hardening steel 167 

tempering steel 165 

Heat value of fuels 354 

Heat and work 349 

heat transformation 354 

heat transmission 349 

laws of gases 352 

thermodynamics of steam 356 

Heating for public garages 249 

Heavy sheet-steel welding 61 

expansion and contraction 63 

preparation 61 

types of welds in heavy sheet 64 

welding heavy sheet 63 

Heavy welding section 68 

hammering 69 

Heavy work, soldering 134 

High pressure, effect of 363 

High-speed motors in motorcycles 272 

History of motorcycle 271 

early machines • 271 

influence of high-speed motors 272 

light-weight machine 273 

modern improvements 273 

two-cylinder motors 272 

Hose for welding apparatus 31, 37 

care of 31 

position of 37 

Hot-riveting metals 160 

rivet set 161 

Ignition, motorcycle 327 

Income and expense estimates of 

public garages 232 

analysis of actual estimate 233 

analysis of revised estimate 233 

Note. — For page numbers see foot of page: 


Indicator card, effect of compres- 
sion on 362 
Indicator diagrams 362 
Injector blowpipe 17 

Jigs 57, 126 

Joints in sheet-aluminum welding 79 
Joy valve gear 3«R 


Kerosene as fuel for steam cars 374 
Keyseating, hand 156 

Keyway, laying out 156 

Land values and size of 

Lapping cylinders 

cleaning after grinding 

emery paste 

lapping by drill press 

lapping by hand 

worn cylinders 
Lapping in piston ring 
Large size garage 

elevators vs. ramps 

general characteristics 

typical arrangements 

layout 9 

layout 10 

layout 11 

layout 12 
Latent heat 
Lathe and accessories 

grinding in lathe 

milling in lathe 
Lathe equipment for repair 
Lathe tools for repair shops 
Lathe work, simple 

centering stock 

finish cut 

reversing work 

roughing cut 

squaring-off work 








Digitized by 





Lathes (continued) 

Machines and machine processes 



in repair work (contin- 

degrees of fit between shaft and 




arbor presses and gear pullers 


lathe equipment 


drill presses 


lathe tools 




mounting work 




simple lathe work 


miscellaneous equipment 


Lead burning 


power hack saws 




shape rs 


different methods 


Magneto generators 




Malleable-iron welding 


Lead-burning apparatus 




burning on connecting links 


fusion weld not possible 


burning terminal groups 


malleable iron 


forms or molds 


Management and care of steam 







adjusting throttle 


Light sheet-steel welding 


care of burner 


expansion and contraction 


care of engine bearings 




causes of low pressure 


welding light sheet 


end of run 


Light-weight motorcycles 


engine lubrication 




filling boiler 








fusible plug 


Light work, soldering 


gasoline pump 


Lighting of public garage 


general lubrication 


artificial lighting 


management on road 


natural light 


operating cut-off and reverse 


Lubrication in drilling 147 

, 182 

operating instructions 


Lubrication of motorcycles 303 


raising gasoline pressure 


oil pumps 


scale prevention and remedies 


path of oil 


water pump 



Manifolds, repair by welding 


Mechanical elements of steam 


Machine tools for public garages 




drill press 


slide valve 


emery wheel, or grinder 


superheated steam and com- 

grinding in lathe 


pound expansion 


hack saw 


valve gears 




Mechanical equivalent of heat 


lathe accessories 


Medium size garage, typical ar- 

milling in lathe 


rangements for 


utility of portable electric motor 265 

layout 6 


Machines and machine processes 

layout 7 


in repair work 


layout 8 


Note. — For page numbers see foot of pages. 


Digitized by 



Melting point of metals 

Merkei motorcycle 

Metals, properties of 
coefficient of expansion 
expansion and contraction 


handling complex case of expan- 
sion and contraction 49 
handling simple case of expan- 
sion and contraction 47 
melting point 44 
specific heat 46 
thermal conductivity 44 
Micrometer 139, 141 
Milling in lathe 264 
Milling machines 193 
Motor, dismounting 128 
Motorcycle bodies and attach- 
ments, special 320 
front stand 325 
passenger attachments 320 
Motorcycle chains, cleaning 340 
Motorcycle engine, principles of 

operation 289 

four-cycle 289 

two-cycle 291 

Motorcycle improvements 273 

Motorcycle mechanism nomencla- 
ture 287 
Motorcycle types, developments 

in 282 

four-cylinder 285 

two-cylinder 282 

Motorcycles 269-342 

analysis of mechanisms 287 

construction details 293 

evolution of 269 

history 271 

operation and repair of 325 

present trend of models 271 

principles of engine operation 289 
special bodies and attachments 320 
standard specifications 269 

types of 274 

Motors, motorcycle 295, 325 

European high-speed type 301 

four-cylinder type 300 

operating suggestions 325 

Note. — For poQt numbera aee foot of pag—. 


Motors, motorcycle (continued) 

single-cylinder type 295 

two-cylinder type 297 

Muffler, dirty 341 

Neutral flame 




Ofeldt boiler system 399 
automatic fuel feed 400 
fuel, water, and steam connec- 
tions 399 
Oil pumps 303 
Oily motorcycle clutches 339 
Oils for public garages 252 
Open circuits 342 
Operating cut-off and reverse on 

steam ca'rs 409 
Operating suggestions for motor- 
cycles 325 
carburetor 327 
control 329 
ignition 327 
lubrication 328 
motor 325 
tires 329 
valves 326 
Operation and care of welding 

apparatus 26 
general notes on welding 40 
hose for welding outfits 31 
instructions" for connecting ap- 
paratus 32 
necessary apparatus 26 
necessity for care 26 
regulators 29 
welding blowphpe 26 
Operation and repair of motor- 
cycles 325 
operating suggestions 325 
repair of motorcycles 332 
Overhead welding 41 
Oxidation 78 
Oxidizing flame 36 
Oxy-acetylene cutting 20, 86 


Digitized by 



Oxy-acetylene flame, character of 

18, 34 
carbonizing, or reducing, flame 36 
caution against oxidizing flame 36 
flame regulation 35 
neutral, or welding, flame 35 
oxidizing flame 36 
use of reducing flame 36 
Oxy-acetylene process 13, 34 
advantages of 13 
character of flame 34 
expansion and contraction 18 
flux 19 
gases 13 
generators 15 
oxy-acetylene cutting 20 
oxy-acetylene flame 18 
preparation of work 18 
strength of weld 19 
welding blowpipes 17 
welding rod 18 
Oxy-acetylene welding practice 11-112 
introduction 1 1 
miscellaneous processes 86 
technic of oxy-acetylene welding 24 
welding processes 11 
Oxy-acetylene welding technic 24 
general notes on welding 40 
instructions for connecting ap- 
paratus 32 
operation and care of apparatus 26 
simple welding job 24 
welding for different metals 44 
Oxygen, cutting with 87 
Oxygen consumption, measuring 109 
Oxygen welding regulator 30 

Passenger attachments for motor- 
cycles 320 
Peening 172 
Pilot light for steam cars 376 
Piston rings, fitting 135 
fitting new rings 138 
fitting ring in groove 135 
importance of piston rings 135 
lapping in ring 136 
Not*. — For page numb*r$ «e« foot of pages- 

Piston rings, fitting (continued) 
miscellaneous adjustments of 

piston rings 138 

replacing rings 137 
testing and correcting length of 

ring 136 

Pitch diameter of gear 169 

Pitch of gear 169 

Planers 194 

Portable electric motor 265 

Power hack saws 182, 262 

allowance for cut 183 

method of action 182 

pressure on blades 182 

pressure for different metals 183 

Power provision for public garages 251 

Pre-heating in welding 50 

charcoal fire 53 

gas and oil burners 52 

methods 51 

reasons for 50 

Preliminary operations in welding 32 

Pressed-steei parts of car, repair 

by welding 97 

Pressure blowpipe 17 

Public garage equipment 246 

air-supply system • 254 

drainage 250 

fuels and oils 252 

garage furniture 255 

garage tools 260 

heating 249 

lighting 246 

major equipment 246 

provision for moving cars 251 

provision for power 251 

special stands for units 259 

ventilation 249 

water supply 249 

work benches 257 
Public garages 197-266 

designs of 207 

finances and building costs 232 

location 200 

necessary equipment 246 

preliminary problems 197 

range of business 197 


Digitized by 





Public garages (continued) 

typical exterior design 






Radiation of heat 


Reamers, kinds of 


fluted chucking 




three-flute chucking 


Reaming in shop . 


characteristics of hand reamings 154 

clearances 153 

function of reamer 151 

kinds of reamers 154 

number of teeth 152 

Rebabbitting, jig for 126 

Rebabbitting bearings 126 

finishing bearing 128 

pouring babbitt 127 

types of jig to use 126 

Reducing flame 36 

Regulation in electrical system of 

motorcycles 315 

ammeter 317 

fuses 318 

one- and two- wire systems 317 

spark plugs 319 

storage batteries 318 
Regulators for welding apparatus 


acetylene regulator 30 

care of regulators 31 

operation of regulator 29 

oxygen welding regulator 30 

Relative conductivity 350 

Removing carbon 95 

old process 95 

oxygen process 96 

Repair of motorcycles 332 

air leaks in inlet manifold 333 

big-end piston bearings 335 

carburetors 332 

cleaning chains 340 

dirty muffler 341 

electrical troubles 342 

Not*. — For page number* nee foot of paaen. 


Repair of motorcycles (continued) 

gaskets and washers 336 

oily clutches 339 

overhauling 334 

piston pins 335 

tires 329 

truing up crankshafts 336 

valve timing 337 

valve troubles 333 

valves 335 

Repair shop equipment 173, 193 

Reverse, operating on steam cars 409 

Revolving filing 125 

Ring gear, installing new 161 

heating rivet 161, 162 

making rivet Bet 161 

removing old gear 161 

Riveting 158 

brake linings 158 

clutch facings 159 

cold-riveting metals 160 

hot-riveting metals 160 

installing new ring gear 161 


Safe edge file, use of 123 

Scale prevention and remedies 405 

Shaft and hole, degrees of fit 189 

Shafts and axles, repair by welding 103 

Shapers 190 

characteristics 190 

clamping work in shaper 190 

operation suggestions 192 

Sheet-aluminum welding 79 

types of joints 79 

welding process 80 

Shop equipment, importance of 115 

Shop information 115-194 

bench work 115 

importance of shop equipment 1 1 5 

machines and machine processes 173 

Short-circuits 342 

Single-cylinder motorcycle engine 

295, 339 

Size of public garage, determining 201 

methods of arranging cars 202 

methods of calculating size 201 


Digitized by 




Size of public garage, determining 
modifications of size due to sit- 
uation 204 
other modifications and deduc- 
tions 205 
Slide valve on steam car 360 
effect of adding steam lap 363 
effect of compression on indica- 
tor card 362 
effect of high pressure and early 

cut-off 363 

elementary slide valve 360 

indicator diagrams 362 

use of steam cut-off 361 

Small size garage 207 

layout 1 207 

layout 2 208 

layout 3 208 

layout 4 209 

layout 5 210 

Smith motor wheel 274 

Soldering 133 

general instructions 133 

heavy work 134 

light work 134 

position of work 134 

soldering flux 133 

soldering irons 135 

special stoves 135 

use of blow torch 134 

Spark plugs 319 

Specific heat 46, 354 

Spot- welder, electric 21 

Spring construction of motorcycles 293 

rear and front frame springs 294 

seat-post springs 293 

Springs, repair by welding 102 

Standard threads in tapping 147 

Stanley fuel, water, and steam 

systems 389 

Stanley steam car 369 

Starting, motorcycle 305 

Steam automobiles 345-41 1 

automobile boilers 380 

boiler accessories and regulation 388 

characteristic features 346 

Note.— Per pagt numbtrs tee foot of page*. 

Steam automobiles (continued) 
engine types and details 369 

fuels and burners 374 

heat and work 349 

introduction 345 

management and care of steam 

cars 400 

mechanical elements of steam 

engine 359 

Steam engines, development of 345 

hardening 166 

tempering 165 

Steel welding 53 

general considerations 53 

heavy sheet-steel welding 61 

light sheet-steel welding 56 

welding heavy steel f orgings and 

steel castings 67 

Stephenson link valve gear 367 

Storage batteries 318, 342 

Strength of weld 19 

experience of operator 19 

working and hammering 19 

Superheated steam 364 

Superheating 358 

Taper pins, fitting 155 

amount of taper 155 

reamers and taper pins available 155 

Tapping in repair shop work 147 

dies 150 

standard threads 147 

tapping process 150 

taps 148 

Taps used in repair shop 148 

bottoming tap 150 

plug tap 149 

taper tap 149 

Temperature scales 351 

absolute zero 351 

conversion of scales 351 

Tempering steel 165 

Thermal conductivity 44 

Thermodynamics of steam 356 

Threads, standard 147 


Digitized by 




Tires, motorcycle 329 

Tool equipment for larger public 

garages 265 

Twin-cylinder motorcycle engine 339 
Twist drills n* 

Two-cycle motorcycle engine 
Two-cylinder motorcycle engine 

272, 297 



Vacuum machinery, use of in pub- 
lic garage 228 
Valve gears, steam cars 367 
throttling- and reversing 367 
types of gears 367 
Valve timing for motorcycles 337 
getting valve timing with scale 338 
marking flywheels — automobile 

practice 338 

marking gears 337 
opening of valves not on dead 

center 338 

Valve troubles of motorcycles 333 

Valves, motorcycle ^ 326 

Ventilation of public garages 249 

Vertical welding 41 

Very large garage 227 

layout 13 227 

layout 14 228 

layout 15 230 

Vises 261 

Water pump 407 
Water supply for public garages 249 
Water-tube boilers 382 
defects in 42 
strength of 19 
Welding (see Oxy-acetylene weld- 
ing practice) 11 
costs 109 
general notes on 40 
old and new methods of 11 
Welding aluminum 78 
cast aluminum 81 
general considerations 78 
sheet aluminum 79 

Note. — For page numbers see foot of page*. 


Welding apparatus 
instructions for connecting 24, 32 
manipulation of blowpipe and 

welding rod 37 

oxy-acetylene blowpipe flame 34 

preliminary operations 32 

starting work 33 

operation and care of 26 

Welding in automobile repair 

shops 11 
electric processes 21 
miscellaneous processes 86 
oxy-acetylene process 13 
technic of oxy-acetylene weld- 
ing 24 

Welding blowpipes 17, 26 

injector blowpipe 17 

pressure blowpipe 17 

welding heads and tips 26 

working pressures 27 

Welding brass and bronze 84 

after-treatment 86 

general considerations 84 

preparation 85 

welding 85 

Welding cast iron 69 

expansion and contraction 70 

flux 71 

general considerations 69 

oxidation 69 

pre-heating 70 

preparation of welds 72 

welding process 73 

welding rods 70 

Welding copper 82 

after-treatment 84 

general considerations 82 

preparation 83 

welding 83 

Welding different metals 44 

aluminum welding 78 

brass and bronze welding 84 

cast-iron welding 69 

copper welding 82 

malleable-iron welding 77 

pre-heating 50 

properties of metals 44 


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Welding different metals (contin- 

Welding steel (continued) 


general considerations 


steel welding 


heavy sheet steel 


Welding flame 


heavy steel forgings and steel 

Welding flux 




Welding heavy sheet 


light sheet steel 


continuous welding 


Welds in heavy sheet 


types of welds 


butt weld 


welding by sections 


corner welds 


Welding heavy steel forgings and 



steel castings 


high-pressure tanks 


expansion and contraction 


lap weld 


heavy section 


storage tanks 




tank heads 


Welding job, simple 


tank rings 


apparatus required 


tubes and pipes 


connecting apparatus 


Welds in light sheet 


preparing metal 


butt weld 




corner welds 


Welding malleable iron 






flange weld 


malleable iron 


lap weld 


Welding processes 


pressure tanks 


electric processes 


storage tanks 


old and new methods 


tank heads 


oxy-acetylene process 




Welding rods 18 


Woodruff keys 


position of 


Work benches 



Welding steel 


Work vises 


Note. — For page number a tee foot of page*. 


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