PRINCIPLES
OF
MACHINE WORK
PRINCIPLES OF MACHINE WORK.
IRobert Ibenrs Smttb
Massachusetts Institute of Technology
Text-Book of the Elements of Machine Work
192 pp., 5x8, 204 Illustrations.
Text-Book of the Principles of Machine Work
393 pp., 5x8, 441 Illustrations.
Text-Book of Advanced Machine Work
350 pp., 5 x 8, 400 Illustrations.
INDUSTRIAL EDUCATION; BOOK COMPANY
BOSTON, U. S. A.
TEXT-BOOK OF THE PRINCIPLES
OF
MACHINE WORK
PREPARED FOR
, STUDENTS IN TECHNICAL, MANUAL TRAINING,
AND TRADE SCHOOLS, AND FOR THE
APPRENTICE IN THE SHOP
ENGINE AND SPEED LATHES, DRILLING AND GRINDING
MACHINES, CARBON AND HIGH SPEED STEEL CUT-
TING TOOLS, MEASURING, TURNING, FITTING,
THREADING, CHUCKING, DRILLING,
BEAMING, JIGS, FIXTURES AND
CYLINDRICAL GRINDING
BY
ROBERT H. SMITH
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
441 Illustrations V
SECOND EDITION
INDUSTRIAL EDUCATION BOOK COMPANY
BOSTON, U. S. A.
Engineering
Labrary
COPYRIGHT, 1910, 1912,
BY
ROBERT H. SMITH.
Stanhope iprcsft
F. H. G1LSON COMPANY
BOSTON. U.S.A.
PREFACE.
IN teaching mathematics, physics, chemistry, etc., text-
books of classified information are available and are a required
and necessary part of class-room and laboratory courses;
thus the student advances rapidly and systematically, and
the instructor is enabled to accomplish effective work.
In this the Age of Machinery, students, apprentices, and
machine operators are handicapped by lack of text-books of
classified information of the art and science of machine con-
struction.
The aim of these books, Elements of Machine Work,
Principles of Machine Work, and Advanced Machine Work
is to give the beginner the advantages of text-books as in the
older subjects, that he may acquire the fundamental as well
as advanced principles in a logical, systematic, and progressive
manner and in the shortest time possible.
Machines, mechanisms, and tools are illustrated graphically
by means of original perspective and mechanical drawings,
and briefly and systematically described by condensed tables.
Operations in machining, standard and typical problems in
machine construction are given in condensed schedules which
name the material, operations, machines, speeds, feeds, jigs,
fixtures, and tools. Calculations are supplied by condensed
rules and formulas. Facts and principles are supplied which
a student or apprentice in school or shop must rediscover or
obtain from instructor or foreman. As the subject is large
and varied, it is impossible for instructor or foreman to do
justice to it; consequently, the task is a difficult one and
the beginner's progress extremely slow.
These books tell how to do things, with that theory which
connects principles and practice, and no person can build or
257786
vi PREFACE.
superintend the construction of machinery without con-
sciously or unconsciously understanding these problems and
applying these principles.
To the manufacturers, teachers, associates, and other friends
who have kindly assisted with information, help, and encour-
agement, I take this opportunity of expressing my indebted-
ness and appreciation.
R. H. S.
May,. 1910.
PREFACE TO SECOND EDITION.
THE increased efficiency obtained at the Massachusetts
Institute of Technology by using the text-books Elements of
Machine Work and Principles of Machine Work, and the
splendid reception given them by the Technical Press, schools
and shops, teachers and students, apprentices and mechanics,
has justified their production and shown the need of text-
books on machine work as stated in the Preface to the first
edition; and the growing number of state universities, techni-
cal, trade and manual training schools that are adopting these
books as a required text in their courses is gratifying.
The author desires to express his thanks to the teachers
and educators, manufacturers and engineers, foremen and
mechanics, and other friends, in all parts of the country, for
valuable suggestions and kindly criticisms.
R. H. S.
Boston, May, 1912.
. CONTENTS.
CHAPTER I.
PAGE
Engine Lathes, countershaft, line shaft, and belt connections
described Horizontal section of headstock Transparent
view of lathe apron, showing the three distinct feed mechanisms
Swing, length, and classes of lathes Attachments for
lathes Engine lathe with rapid change-gear mechanism 1
Electrically-driven Machine Tools. Electrically-driven engine
lathe : 9
Speed Lathes. Countershaft, line shaft, and belt connection de-
scribed Lubricating bearings Treatment when bearings
rough up Rust or corrosion Changing speed belts of lathes
Warning against loose sleeves and careless actions near run-
ning belts, gears, milling cutters, etc 11
CHAPTER II.
Truing and Alining Centers. Center gage Requirements for
successful use of engine lathe Truing engine lathe centers with
center truing tool Grinding centers Truing speed lathe
centers Setting dead center in alinement for straight turning. 15
Center Holes in Lathe Work. Table of center-hole dimensions
Countersinks ? 19
Hand and Machine Methods of Centering. Straightening shafting,
rods, and bolts 23
CHAPTER III.
Cutting Tools. Rake, clearance, and cutting angle denned.
Rough and finish turning 27
Lathe Cutting Tools for Cast Iron, with Chart. Right and left
tools Angles of lathe-cutting tools Height of tools for
cutting operations Rough squaring and turning with round-
nose tools Rough and finish squaring with side tools Rough
and finish turning with diamond-point tool Square-nose
finishing tool 28
vii
viii CONTENTS
Grinding Lathe Tools. Grinding round-nose, side, diamond-point,
square-nose, and threading tools Grinding high-speed cutters
and various hand tools, on grindstone or emery wheel Uni-
versal tool grinder for duplicating shapes and angles of lathe and
planer tools Oilstoning tools 37
CHAPTER IV.
Setting and Using Outside Calipers. Adjusting tool to turn to
desired diameter Transferring settings from one pair of calipers
to another 45
Cutting Speeds, Cut Meter, and Feeds. Cut Meter Attach- _ %
ment for speed indicator for obtaining surface speed Rules
for obtaining cutting speeds Table of cutting speeds for
various metals, including high-speed steels Cutting feeds 47
Lubricants for Cutting Tools. Table showing when to use a lubri-
cant and when to machine dry 50
Inspecting and Measuring Material (Stock), Oiling and Cleaning
Machines. Care of machines, tools, and benches 52
CHAPTER V.
Engine Lathe Work. Time element Schedule drawings of ma-
chine parts How to begin lathe work Mounting work on
centers Turning work from end to end 54
Centering, Squaring, and Straight Turning, with schedule of opera-
tions 57
Filing Lathe Work. Mill files Speed for filing Round and
half-round files for inside rounds and fillets 59
Micrometer Calipers. Micrometer principle of measuring
Measuring the work and reading the micrometer Methods of
holding micrometer to measure work held in the hand, lathe, or
on the bench Large micrometers Table of decimal equiva-
lents of common fractions 61
Vernier Calipers. Vernier principle of measuring Measuring
work and reading the vernier Making inside measurements
with vernier A ten-thousandth micrometer with vernier on
the barrel 65
CHAPTER VI.
Fits in Machine Construction, with Tables of Allowances. Typical
examples of fits Materials used for different kinds of bearings
Classes of fits Allowances and limits for running, driving,
and forcing fits Taper forcing fits Pressure and allowances
for forcing fits . : 68
CONTENTS. ix
PAGE
Forcing Press. Examples of forcing and shrinking fits, with tables
of allowances and limits Holes and hole gages Turning and
filing fits Grinding fits 72
Standard and Limit Gages. Ring, plug, and caliper gages and
reference disks Standard end measuring rods and limit gages
Special gages 77
CHAPTER VII.
Tapers in Machine Construction. How expressed Standard and
special Method of turning Calculating distance to set over
t footstock Using a pattern to obtain set-over 80
Taper Turning and Fitting. Turning, filing, and fitting a Morse
taper, with schedule of operations 82
Taper Attachment for turning tapers in an engine lathe. Turning
a taper on a large drill socket 84
Straight Turning and Fitting. To turn and file a straight running
fit, with schedule of operations 85
CHAPTER VIII.
Lathe Tools for Steel or Wrought Iron. Side and diamond-point
tools Roughing tools Finishing tools Spring and shear
tools Left side and left diamond-point tools Half diamond-
point tools 87
Holders and Cutters. Straight holders and cutters Useful forms
of cutters Chart of lathe tool holders for squaring r turning,
boring, threading, and forming Bent holders Double holders 93
Cutting-Off Tools. Cutting off stock with forged tool Cutting-
off tool holder and cutter 97
Turning Steel. Preparing shaft blanks, with multiple schedule of
operations 98
CHAPTER IX.
Screw Threads. Right and left threads Forms of threads
Single and multiple threaded screws Pitch and lead of thread
Threads per inch Measuring threaded work Counting
threads The Sharp V thread The United States Standard
thread 102
Threading Tools for United States Standard and Sharp V threads
Setting tool 107
Threading or Screw Cutting. Calculating simple gearing Descrip-
tion of screw-cutting mechanism To set up lathe for screw cut-
ting and cutting the thread, with schedule of operations
x CONTENTS
PAGE
Fitting thread to nut To reset tool to resume cut after re-
grinding To cut left threads To thread to a shoulder
Fractional threads and methods of calculating gearing Com-
pound gearing To calculate gearing for a given lead To
calculate gearing for metric screw threads with English lead
screws Translating gears Metric lead screw Catching
the thread or threading long screws without backing belt
Threading taper work Whit worth (English) standard threads 110
Bolt and Nut Making. Squaring and turning bolts. Nut mandrels
Squaring and chamfering nuts, with schedule of operations
Making clamp nut To make finished bolt, with schedule of
operations 121
CHAPTER X.
Chucks. Independent, universal, combination, drill, draw-in, and
special chucks 126
Face Plates. Holding work on face plate Balancing work with
counterweights Holding work with angle plate on face plate
Lathe axis indicator 131
Chucking in engine lathe, with schedule of operations. Chucking
with flat drills and reamers Chucking with drill holder and
steady rest 134
Reaming. Classes of reamers Irregularly spaced teeth Ream-
ers for brass Hand reaming in vise Reaming in vertical
drilling machine and engine lathe, with schedule of operations
Adjustable reamers Reaming stands Fluted chucking
reamers Power reaming in engine lathe, with schedule of
operations Rose chucking reamer Fluted and broach
reamers for taper pins Taper reaming in speed lathe 139
CHAPTER XI.
Mandrels or Arbors solid and expanding Bridges in hollow castings
Revolving dead center for pipe turning Special mandrels
Driving or pressing mandrels in or out of work Mandrel or
arbor block Mandrel or arbor press 146
Mandrel Making. Making a standard lathe mandrel, with schedule
of operations 149
Turning and Finishing Flanges. Rough and finish facing and
turning Making a cast-iron flange, with schedule of operations 152
Turning and Finishing Pulleys. Tapering or crowning face
Making a pulley, with schedule of operations Locating set
screws . . 156
CONTENTS xi
PAGE
Polishing Lathe Work. Abrasives, speeds, and machines used
Order of applying different numbers of emery cloth Polishing
flanges and shafts Polishing brass and copper 160
CHAPTER XII.
Hand Turning. Cutting speeds Methods of holding work in
speed lathe To turn and square with graver and round-nose
tools 164
Making Machine Handles, with schedule of operations Templets
as guides to uniform production 167
Drilling, Tapping, and Hand Threading in Speed Lathe. Chucking
with twist drill in speed lathe Tapping and threading work in
speed lathe Hand chasers to thread screws and nuts, with
method of operation Using the ripper and planisher for brass
finishing Filing brass Burnishers and burnishing metal
Hand cutting-off tools Inside hand turning and boring
Slide rest for speed lathes 171
Spring Winding. Coil springs Winding a compression spring with
a spring winder To gear a lathe to wind a spring Winding
a compression spring with a wire hook 179
CHAPTER XIII.
Brass Finishing. Turning brass in engine lathe Use of round-
nose and front tools Binding post and nuts, with schedule of
operations 182
Machining Bronze, Copper, etc. Aluminium Babbitt Lead
Vulcanite, or hard rubber Fiber Rawhide ._. 187
Nurling. Hand and machine nurling, with schedule of operations 188
Curved Turning and Forming tools for engine lathe work Holders
and cutters 190
Steady and Follower Rests. To turn slender shaft with steady rest
set to spot, with schedule of operations To turn slender shaft
supported by steady rest set to cat head To turn slender
shaft supported by follower rest 191
CHAPTER XIV.
Cylindrical Grinding Machines. Machine grinding The prin-
ciple of grinding on two dead centers Classes of grinding
machines Universal grinding machine, with schedule of
parts 195
Grinding Wheels. Abrasives used in their composition Chart
of wheels Vitrified, silicate, elastic, tanite, vulcanite Cellu-
loid, and combination grinding wheels Shapes of wheels
Mounting wheels Table of speeds Direction of rotation of
xii CONTENTS
PAGE
wheel and work Feed and depth of cut Truing wheels
Truing centers Methods of grinding work Grinding work
straight Grinding work taper Wet and dry grinding
Lubricants for grinding Allowances for grinding Rough and
finish grinding Expansion of work Seasoning Measuring
tools 198
Problems in Cylindrical Grinding. Grinding running fit in uni-
versal grinding machine, with schedule of operations Grind-
ing forcing fit in universal and tool-grinding machine Grind-
ing standard mandrel in universal grinding machine Grind-
ing to a shoulder Commercial grinding Grinding a cast-
iron roll in plain grinding machine Grinding a shaft in plain
grinding machine, with use of back rests Duplicate grinding
in the automatic magnetic sizing grinder Grinding taper
collet Grinding a phosphor-bronze taper bushing 209
CHAPTER XV.
Drilling Machines. Vertical, horizontal, multiple-spindle, and
radial ' 222
Vertical Drilling Machine, with schedule of parts 222
Twist Drills of carbon and high-speed steels Shape and angle of
point Good and bad grinding Lip clearance Thinning
the point 225
Grinding Drills. Drill grinder Machine and hand method of
grinding Drilling cast iron and steel Using high-speed steel
drill twisted from flat bar Flat drills To grind a twist drill v
for brass Straight-groove drill for composition, brass or sheet
metal 227
Sizes of Drills designated by common fractions, letters, and numbers,
with decimal equivalents, gages, and tables Body, reamer, and *
tap drills 234
Speeds and Feeds of Drills. To calculate speeds and feeds of drills
Table of carbon-steel drill speeds and feeds Tables of
spindle speeds for belt-driven vertical drilling machines and
speed lathes Hand and power feeds Tables of spindle and
gear speeds for high-speed drilling machine 237
Laying Out and Drilling Holes. Spring dividers Rough, approxi-
mate, and accurate drilling Laying out the work Inspection
circle Drawing the drill, with schedule of operations Accurate
drilling, reaming, and tapping holes, with schedule of opera-
tions Drilling for set screws Allowances for bolt holes, cap
screws, and stud bolts Three methods of drilling in aline-
ment without a jig To drill work held by hand or in a vise on
the drilling table Drilling work held against an angle plate
CONTENTS xiii
Use of three and four-groove twist drills Drilling diametrically
through a shaft Automatic drill chuck, and collet Cutting
off by drilling Slotting by drilling, plugging, and drilling
Lead holes for large drills Starting a drill on a slanting surface
Drilling part of a hole Cutting boiler-tube holes Drill
extension Leveling work on drilling table Drilling in speed
lathe 242
Deep Drilling. Oil drills Vertical drilling with oil drill Hori-
zontal drilling with hollow oil drill and extension 257
CHAPTER XVI.
Drilling Jigs, and Multiple-Spindle Drilling Machines. Interchange-
able machine parts Classes of drilling jigs Improvised jigs
Plate jigs Drilling and tapping engine cylinder heads
Multiple-spindle drilling machines Box jigs Drilling, ream-
ing, and tapping in different directions with box jig 260
Radial Drilling Machines. Automatic tapping attachment
Plain and universal radial drilling machines Jig vise Drill-
ing and counterboring duplicate parts 265
Taps and Dies. Sizes of taps Hand, nut, pulley, hob, or master,
and adjustable taps Tap wrenches Tap drill holes Loose
nuts Hand tapping a rough nut, with schedule of operations
Accurate hand tapping Tapping in vertical drilling machine,
with schedule of operations Jig tapping Tapping through
holes and bottom holes Removing broken taps Power tap-
ping Tap drills To calculate root diameter for both United
States Standard and Sharp V threads, with tables Hand dies
Automatic dies Power threading Hand threading a bolt,
with schedule of operations 269
CHAPTER XVII.
Bolts and Nuts. Styles of heads Classes of bolts: rough, semi-
finished, and finished Machine, planer, stud, improvised
Expansion, square, and hexagonal bolts Square, hexagonal,
check, and castle nuts 282
Cap and Set Screws. Cap screws, collar screws, and tap bolts
Dowel pins Lag screws, hanger bolts, and wood screws Set
screws Thumb-screws and nuts 287
Machine Screws. Numbered sizes American Society of Mechani-
cal Engineers' Standard, and American Screw Company's Stand-
ard, with tables Tapping with small taps Threading with
small dies Machine screw and wire gages Tables of tap drills. 292
Counterboring and Countersinking. Solid and adjustable counter-
bores Countersinks . . 299
xiv CONTENTS
PAGE
Calculating Diameter of Blank to Mill Square or Hexagonal. Di-
ameter of blank to mill or file square or hexagonal 303
Indexing in Engine Lathe. Dividing the circumference of work
into equidistant parts for drilling, filing, etc 304
CHAPTER XVIII.
Inside Calipers and Inside Micrometers. Measuring diameter of
holes Adjusting tool to bore hole to setting of inside calipers
Inside micrometer calipers, and method of using and reading . . . 305
Boring and Inside Threading. Setting and using boring tools in
lathe Holders and cutters Inside threading tools for United
States Standard or Sharp V threads Setting inside threading
tools Schedule of operations for inside threading Finishing
inside thread with tap Interrupted thread taps Cutting
an inside thread to a shoulder 308
Square Threads. Square threading tools Inclination Holders
and cutters Setting square threading -tools Square thread
taps Method of cutting a square thread screw, with schedule of
operations Making the nut and fitting the screw 314
Acme Standard or 29 Threads. Making the tool Setting 29
threading tools 29 thread taps Cutting a 29 thread screw,
with schedule of operations Making the nut and threading the
screw 325
Multiple Threads. Cutting double square threads, with schedule
of operations Multiple threading tools 335
Alinement Drilling and Tapping. Fixed nuts Drilling and tap-
ping cross-feed screw nut in axial alinement, with schedule of
operations 337
Eccentric Turning. Laying out and turning an eccentric shaft, with
schedule of operations Making an eccentric mandrel
Turning an engine eccentric, with schedule of operations Lay-
ing two throw 90 crank-shaft center fixtures Alining center
fixtures, and laying out cranks Turning crank shaft 338
Testing Lathe Work with Indicators. Testing a mandrel Truing
up work in a chuck Comparing the throw of both ends of an
eccentric shaft Setting center punch mark true to axis of rota-
tion 343
CHAPTER XIX.
Tables and Other Data Used in Machine Work. Electrical units
Automobile screws Bolts and nuts Screw sets in blocks
Comparative drill sizes Morse, Brown & Sharpe, and Jarno
tapers Mandrel dimensions Wood screws Sheet metal,
plate and wire gages 346
PRINCIPLES OF MACHINE
WORK.
ENGINE LATHES.
CHAPTER I.
ELECTRICALLY-DRIVEN MACHINE TOOLS.
SPEED LATHES.
ENGINE LATHES.
1. The engine lathe, Fig. 1, is supplied with hand and
power long, (longitudinal) and cross feeds, and is arranged
for screw cutting, for which a lead screw is provided. The
cutting tool is held in a tool-post which is clamped to the
tool-block and the whole mounted on a carriage. It is usually
constructed with back gears.
CONE HEADSTOCK. COUNTERSHAFT DRIVE. BELT OR
GEAR FEED.
ESSENTIAL PARTS.
2. A Bed.
B and B' Legs fastened to
bed by cap screws, to floor by lag
screws.
C and C" Front ways of two
pairs of V ways, planed and
scraped.
D Headstock bolted to ways.
E Footstock or tailstock ;
position adjustable.
F and F f Bolts for clamping
footstock to ways C.
G Carriage, two parts, mov-
able on ways.
H Saddle ; carries tool mech-
anism
H f Apron ; carries feed mech-
anism.
3.
Footstock.
May be set over for taper
turning.
/ Front screw of a pair for
adjustment of upper part of foot-
stock; back screw not visible.
J Spindle.
K Handle operating foot-
stock spindle.
L Binder for clamping J.
M Dead center.
N Oil well and oiler for dead
center.
PRINCIPLES OF MACHINE WORK.
FIG. 1. H-INCH ENGINE LATHE, COUNTERSHAFT, LINE SHAFT, AND
BELT CONNECTIONS.
ENGINE LATHES.
4. Carriage.
Tool post.
0' Screw for fastening cut-
ting tool.
P Slide rest, rise and fall
type (or elevating rest).
Q Handle for ad justing height
of tool.
R Thread stop, used when
cutting screw threads.
S Handle for operating long,
feed by hand.
T Knob for operating long,
feed by power.
U Handle for operating cross
feed by hand.
V Knob for operating cross
feed by power.
W Lever for operating split
nut (half-nuts) inside apron W .
X Lead screw engaged by
split nut when cutting threads.
Y Feed shaft.
Z Feed rack.
5. Headstock.
1, 2, 3, 4 Steps on headstock
cone. Belt on 1, slowest speed ; on
4, fastest speed.
5 Thrust bearing and end
adjustment.
6 Back gears.
7 Lever for throwing 6 " in "
or " out."
8 Face plate, slotted to re-
ceive dog.
9 Live center.
10 and 10' Oil holes for live
spindle.
6. Feed.
11 Stud on feed spindle;
transmits motion from lathe
spindle to carriage for turning by
12, 13, 14, 15, 16 to feed shaft V;
for screw cutting by 17, 18, 19 to
lead screw X.
A set of change gears is supplied
for screw cutting and gear feed.
12, 13 Feed cones.
14 Feed belt.
20 Index plate of gears, for
screw cutting.
21 Supplementary radial arm
to carry two gears fixed on sleeve,
for compounding change gears for
fine or coarse thread; serves to
connect 22 on 11 to 18, and thence
to X.
22 Gear.
7. Automatic Feed Stop.
23 Automatic stop sleeve.
24 Clutch (23 and 24 used to
stop carriage automatically at
desired point).
25 Clamping bolt (swinging
13 outward tightens feed belt).
26 Gear feed. Remove belt
14, swing 13 until 26 meshes with
18. By different combinations of
gears a large variety of feeds is
obtainable. Six cone belt feeds
are provided by interchanging
16 and 26.
27 Reversing lever ; reverses
feed mechanism in headstock.
8. Countershaft (friction type}
and Line Shaft.
28 Speed belt.
29 Countershaft cone pulley.
30 Headstock cone pulley.
31 Countershaft mechanism
(consists of shaft, cone pulley,
pulley for driving forward belt,
pulley for driving backward belt,
and clutch mechanism).
32 and 32' Hangers bolted to
hanger plank.
PRINCIPLES OF MACHINE WORK.
33 Hanger plank.
34 Line shaft; drives 31.
35 Line shaft hanger.
36 Hanger plank.
37 Driving belt, 34 to 42;
drives lathe forward.
38 Backing belt, 34 to 44;
diives lathe backward.
39 Shipper pole, pivoted to
33.
40 Shipper rod ; controls fric-
tion-clutch mechanism.
41 Expanding clutch; en-
gages pulley, driving lathe for-
ward.
42 Driving pulley.
43 Expanding clutch ; en-
gages pulley, driving lathe back-
ward.
44 " Backing " pulley.
(To run lathe "forward," push
shipper to left ; clutch 41 engages
42; "backward," push shipper
to right ; clutch 43 engages 44.
FIG. 2. HORIZONTAL SECTION OF ENGINE-LATHE HEADSTOCK.
9. Back Gears and Headstock.
(Fig. 2.)
Back gears are used to reduce
speed and increase power of ma-
chine. Ratio is about 10 to 1.
A Cone pulley ; running fit
on spindle.
B Spindle.
(7 Gear fast to cone pulley.
D Gear keyed to spindle B.
E Slide bolt to fasten A to D.
F Slide nut.
G and G' Back gears fast on
sleeve.
H Sleeve ; running fit on
shaft.
/ Eccentric shaft.
J and J' Brackets, part of
headstock casting.
K Lever to rotate shaft 7,
throwing back gear "in " or "out. "
L Live center; taper fit in B.
ENGINE LATHES.
M and M ' Oil holes (oiled
before using back gears).
N and A" Oil holes (oiled
before using back gears).
To Operate Back Gears.
For direct cone drive, slide nut
F is in slot in cone A, back gears j
"out." To use back gears, drop
bolt E and secure, throw lever
K forward. To obtain direct cone
speed again, throw lever back,
loosen E and turn lathe until
F engages slot in A. Tighten E.
Double and Triple Back Gears.
To obtain a greater reduction of
speed, lathes are built double or
triple back geared.
Attention. Gear guards are often provided to prevent accident
and to keep dirt and chips from gear teeth.
10. A typical lathe apron. Fig. 3. The apron of a lathe
carries the greater part of the feed mechanism. Fig. 3 shows
a lathe apron and the three distinct mechanisms, the long,
feed, cross feed, and screw-cutting feed. The first is used for
moving carriage back and forth along bed for turning; the
second for moving cross slide in and out for squaring; the
third, the lead screw and split nut, for moving carriage along
bed for cutting screw threads.
To change direction of feeds. The reversing mechanism to
change direction of rotation of feed shaft may be in the head-
stock and operated by lever 27, Fig. 1, or in the lathe apron.
LONG. FEED. CRO3S FEED. LEAD SCREW.
11.
Long. Feed.
A Long, feed handle.
B Pinion.
C Spur gear.
D Sliding stud.
E Sliding pinion, on inner
end of stud D.
F Feed rack, fastened to
under side of bed
G Splined feed shaft.
H Feather-keyed worm held
in bracket H f .
J Worm gear.
K Friction clutch to connect
J and L.
L Pinion fast to K.
M Knob controlling clutch
K. Hand long, feed is obtained
by rotating A which drives
through B, C, E to F. Power
long, feed is obtained from G.
Clutch K, shown out of action, is
thrown in, which causes G to
drive through H, J, L, C, E to F.
PRINCIPLES OF MACHINE WORK.
ENGINE LATHES.
12.
Cross Feed.
in nut
1 Cross-feed handle.
2 Operating screw,
under cross slide.
3 Bevel pinion feather-keyed
to G.
4 Bevel gear.
5 Pinion fast to 4.
6 Driving gear.
7 Pinion fast to 6.
8 Gear always in mesh with
7.
9 Cross-feed pinion.
10 Knob controlling posi-
tion of 8. Hand cross feed is
obtained by rotating handle 1.
Power cross feed is obtained by
meshing 8 with 9 by means of
knob 10.
13. Lead Screw and Split Nut.
II Lead screw.
III Split nut.
IIP Split nut bracket.
IV Lever to operate split
nut III.
V and V Cams closing split
nut III.
VI Knob to disengage E and
F when screw cutting. To op-
erate for screw cutting, pull out
knob VI, throw IV downward,
closing split nut III.
There are types of lathes, where a splined lead screw per-
forms the combined duty of feed shaft and lead screw, the
worm and bevel pinion being driven directly by it.
Attention. Care should be taken not to have both long, feed
and lead screw thrown in at the same time. Some lathes
are fitted with devices which will prevent this.
14. Swing of lathes. A lathe is designated by its swing and
total length of bed. A 14" X 6' engine lathe will swing four-
teen inches in diameter over ways, but will only swing about
8" over a rise and fall rest, and about 10" over a plain or
compound rest. In length it will turn six feet less the com-
bined length of head and footstock. A 6' bed will turn about
42" between centers.
15. Classes of lathes. Lathes are divided into many
classes, some of which are designed especially for the work
performed upon them, as the wheel lathe, axle lathe, pulley
lathe, turret lathe, bench lathe, jeweler's lathe, etc., and for
ordinary work the engine lathe, which when supplied with
special attachments is called a tool-maker's lathe.
8 PRINCIPLES OF MACHINE WORK.
16. Attachments for lathes. Among the attachments for
lathes are the taper attachment, compound rest, steady rest,
follower rest, and attachments for milling and grinding.
17. Stops for duplicating sizes. In addition to the thread
stop some lathes are equipped with long, and cross-feed stops.
After the first piece is turned or threaded to size, the back
stop is set to check movement of cross slide. The carriage
or long, stop is used for shoulders and lengths. By aid of
these stops a number of pieces can be duplicated.
p JG> 4. ENGINE LATHE WITH A RAPID CHANGE-GEAR MECHANISM.
ENGINE LATHES.
9
18. Lathe with a rapid change- gear mechanism for
threads and feeds. Some lathes, as in Fig. 4, are equipped
with a rapid system of change gears by which different
threads or feeds are obtained quickly.
ESSENTIAL PARTS.
A Change gears in cone form,
on end of lead screw.
B Handle operating change
gears.
C Compound gears.
D Handle operating com-
pound gears.
E Index plate, giving posi-
tions for handles B and D to cut
a desired thread.
F Sector to carry gear for
cutting special thread.
G Lever to reverse carriage.
H and K Automatic car-
riage stops. Carriage stop (in-
visible) is located on back ways
under letter L.
19. Cutting a screw using a rapid system of change
gears. To cut a screw of five threads per inch, find 5 on
index E. and place handle B in notch and hole under it;
place handle D under hole 3 on compound gear box, which
is indicated in the third column on the same line as 5.
For threads given on the index, no change of gears is neces-
sary. Gears may be calculated for other threads and applied
as on the ordinary lathe. The feed for turning is seven
times threads per inch expressed in turns per inch of tool
travel.
20. For threading short screws the carriage may be re-
versed by moving reversing lever G up or down, depending on
whether a right or left thread is being cut; or the automatic
stops H and K may be used.
ELECTRICALLY-DRIVEN MACHINE TOOLS.
21. Arrangement of machine tools for electric 'drive.
They may be group-driven by electricity by using a constant-
speed motor to drive group line shaft, or individually driven
by attaching a constant or variable-speed motor to each
machine. Constant-speed motors are used on machines that
need but little speed variation, or on machines that have a
large variety of mechanical speed changes.
10
PRINCIPLES OF MACHINE WORK.
22. Electrically-driven engine lathe Variable-speed motor
A, Fig. 5, gives a wide speed variation. Speed is electri-
cally controlled from apron. To start lathe, move handle B
in direction of arrow. Controller C is provided with gradu-
ated wheel D. When a desired speed is obtained, pin E is
VARIABLE SPEED
MOTOR
A
HANDLE TO START, STOP,
REGULATE AND REVERSE SPEED:
FIG. 5. ELECTRICALLY-DRIVEN ENGINE LATHE.
placed in wheel D so that it will come against stop F. By
this arrangement any speed can be duplicated. Pin G pre-
vents lathe from being reversed. When it is desired to
reverse lathe, remove pin G and move handle B in opposite
direction. Wheel H is used to revolve lathe spindle by
hand.
SPEED LATHES.
11
SPEED LATHES.
23. Speed lathe, Fig. 6 (often called a hand kthe), on
account of its high speed and simplicity has a wide use in
machine construction for hand turning, drilling, chucking,
filing, polishing, etc.
CONE HEADSTOCK. COUNTERSHAFT DRIVE.
ESSENTIAL PARTS.
24.4 Bed.
B and B f Legs fastened to
bed and floor.
C and C" V ways planed and
scraped.
D Headstock bolted to ways.
E Footstock, position ad-
justable.
F Clamp to fasten footstock
to ways.
G Spindle.
H Handle operating foot-
stock spindle.
/ Binder for clamping G.
J Dead center.
K Oil well and oiler for
dead center.
L Tee rest.
M Tee-rest holder.
N Screw to hold M in place.
Slide.
P Lever to clamp where
desired.
25.
Headstock.
1, 2, 3, 4 Steps on headstock
cone.
5 Thrust bearing and end
adjustment;
6 Face plate, slotted to re-
ceive dog.
7 Live center.
8 and 8' Oil holes for live
spindle.
26. Countershaft (tight and loose
pulley type) and Line Shaft.
9 Speed belt.
10 Countershaft cone pulley.
11 Headstock cone pulley.
12 Countershaft mechanism
(consists of shaft cone pulley,
tight and loose pulley, and belt-
shifting mechanism).
13 and 13' Hangers (bolted
to hanger plank).
14 Hanger plank.
15 Driving belt.
16 Wide straight-faced pulley.
17 Line shaft.
18 Line-shaft hanger.
19 Hanger plank.
20 Shipper rod carrying two
belt fingers.
21 and 21' Belt fingers (21'
not visible).
22 Snipper pole pivoted to
14 and to 20. Belt fingers 21 and
21', between which belt 15 passes,
are moved by 20 by means of 22,
shifting belt from loose to tight
pulley.
23 Loose pulley.
24 Tight pulley.
12
PRINCIPLES OF MACHINE WORK.
FIG. 6. SPEED LATHE, COUNTERSHAFT, LINE SHAFT AND BELT
CONNECTIONS.
OILING MACHINES. 13
27. When and how to oil the bearings of machine tools. -
All bearings must be regularly oiled. Use good lubricating
oil, machine oil, not lard oil. If the oil does not sink into
the oil holes, they should be cleared out. A few drops of oil
in each bearing is enough, Fig. 7. Plane bearings, as the
FIG. 7. OILING SPINDLE FIG. 8. OILING WAYS OF
OF A MACHINE. A MACHINE.
ways of a lathe, should be wiped with waste before oiling
and the oil distributed with the fingers, Fig. 8. Oil twice
a day. All automatic oilers should be filled periodically.
28. Treatment when bearings rough up and machine stops
from lack of oil or too close adjustment. First force in a
liberal quantity of oil; if this does not release the bearing,
force in naphtha or benzine and then more oil ^ if the latter
is not effective, take the bearing apart and smooth the rough
places on the journal by filing and those in the box by scrap-
ing or filing. Then wipe clean, oil freely, and put bearing
together and adjust to run loosely for a while.
29. To prevent rusting or corroding of machine or finished
work, coat with vaseline or thin oil. When tools or machines
are not in use,- coat with a thick oil. The rust should be
removed from a surface before it is oiled or rusting will
continue.
30. Putting on and pushing off belts. An ordinary over-
head belt is thrown off by pressing with a pole against the edge
of the belt at the receiving side of driving pulley. This belt
may be replaced by arranging belt upon driven pulley and
then pushing belt upon driving pulley by starting it at the
14 PRINCIPLES OF MACHINE WORK.
receiving side with a pole that has a bent piece of iron fastened
to its end. For large belts, a ladder must be used and the
belt pushed on by hand. A stout cord may be used to pull on
large belts.
31. To change to higher speed. Start lathe, push belt
off step of head cone with right hand. Press lightly against
inside of down-running belt with either hand to take up slack
and with other hand push the up-running side of belt to the
desired step on counter cone, then with left hand press belt
on- to head cone.
32. To change to lower speed. If belt is on largest step
of counter cone, with left hand pull it on to desired step, then
with same hand press belt on to corresponding step of head
cone. If, however, belt is not on largest step, first push it
off step of head cone with right hand.
Attention. Keep fingers straight and stiff and do not try
to hold belt when pushing on or off.
Warning. To prevent accidents, do not wear loose sleeves
or be careless in your actions near running belts, gears, mill-
ing cutters, etc.
CHAPTER II.
TRUING AND ALINING CENTERS. CENTER HOLES IN
LATHE WORK. HAND AND MACHINE METHODS
OF CENTERING.
TRUING AND ALINING CENTERS.
33. Center gage A, Fig. 9, is used for defining angles of
60. The large notch is used for testing lathe centers, as ;
notches C and D for testing and setting outside threading
FIG. 9. TESTING ANGLE OF LATHE CENTER.
tools, and E for inside threading tools. At F is a table of
double depths of Sharp V threads for determining diameter
of tap drills by subtracting number in thousandths opposite
pitch from diameter of tap.
34. Requirements for successful use of engine lathes.
Engine lathes should be accurate enough to turn, bore and
face straight and true, and be equipped with an accurate
lead screw for screw cutting.
To produce accurate work requires that both live and
dead centers should be true and in accurate aline ment.
Furthermore, lathes wear, causing loss of alinement and
looseness of working parts that must be detected and cor-
rected.
35. Lathe centers. The dead center is hardened and tem-
pered. The live center may or may not be hardened.
15
16
PRINCIPLES OF MACHINE WORK.
To test truth of live center of any lathe. Move foot-
stock until dead center is close to live center, run lathe at
highest speed, look for error. Move lathe tool close to re-
volving live center or use test indicator.
36. To true engine-lathe cen-
ters. Figs. 10 and 11.
FIG. 10. LOCATING CENTER IN
HEADSTOCK SPINDLE.
FIG. 11. TRUING ENGINE-LATHE
CENTER.
SCHEDULE OF OPERATIONS.
Live Center.
1. Remove center.
2. Clean hole and center with
waste.
3. Insert center with lines
coincident A, B, Fig. 10.
4. Drive center lightly with
lead hammer.
5. Start lathe; if still out of
true, use center-truing tool A,
Fig. 11. BC shows cutting edge,
D the clearance.
6. Fasten tool lightly at height
of center.
7. Adjust edge to fit center.
8. Clamp tool tightly.
9. Run lathe at moderate
10. Operate both long, and
cross feeds slowly by hand.
11. Test with center gage.
Readjust tool, if necessary, until
center fits gage.
12. Turn point E at a more
obtuse angle. Portion F may be
cut away in advance to facilitate
truing center.
Attention. Centers may be trued by means of a compound rest.
In an emergency a right side tool may be used back of the center and
the lathe run backward.
TRUING AND ALINING CENTERS.
17
SCHEDULE OF OPERATIONS. Concluded.
Dead Center.
1. Remove center.
2. Anneal.
3. Insert in live spindle.
4. True similarly to live center.
5. Run lathe at high speed.
6. File center with 8" mill file.
7. Polish slightly with fine
emery cloth held under file.
8. Reharden.
9. Temper to light straw color.
Attention. Both centers may be hardened and kept true by
grinding.
37. To grind hardened and soft centers. Fig. 12.
FIG. 12. TRUING CENTERS WITH CENTER GRINDER.
SCHEDULE OF PARTS.
A Frame.
B Clamp fastening A to
footstock spindle.
C Emery-wheel spindle set
at angle of 60 with center.
D Friction roll.
E Bracket ; clamps support
for D to bed.
F Emery wheel.
G Shaft driving F.
H Universal joint.
/ Bevel gears (encased).
J Knob to move emery
wheel back and forth along
center.
Attention. The depth of cut is regulated by footstock spindle.
18
PRINCIPLES OF MACHINE WORK.
38. To true speed-lathe centers, Fig. 13, set rest A close to
center B and adjust till graver C is at height of center. Turn
with graver and test with gage. The dead center is first
FIG. 13. TRUING SPEED-LATHE CENTER.
annealed, inserted in live spindle and trued; then filed, pol-
ished, hardened, and tempered.
39. To set dead center in aliniement to turn straight.
ENGINE LATHE
FOOTSTOCK
FIG. 14. SETTING DEAD CENTER IN ALINEMENT. APPROXIMATE
METHODS.
SCHEDULE OF OPERATIONS.
40.
Two Approximate Methods.
I. Unclamp footstock, Fig. 14,
and move upper part A upon B by
screws C and C' (C" not shown)
until zero lines at D coincide.
II. Move footstock until dead
center is close to live center, ad-
just screws C and C", and aline
centers by sight.
41.
CENTER HOLES IN LATHE WORK.
Accurate Method.
19
1. Set dead center by approxi-
mate methods either No. I or
No. II.
2. Mount shaft A on centers,
Fig. 15.
3. Take light cut as shown
dotted at B.
4. . Take out work.
5. Run carriage back near
dead center.
6. Remount work.
7. Take short cut as at C.
8. Caliper at B and C with
micrometer.
9. If not alike, adjust foot-
stock and repeat operations.
FIG. 15. SETTING DEAD CENTER IN ALINBMENT. ACCURATE
METHOD.
Attention. Limit of error permissible: B may be a fraction of a
thousandth of an inch larger than C but never smaller.
This insures the lathe turning slightly large, which is permissible
for ordinary work.
Note. A test indicator and parallel mandrel, preferably of the
length of the work to be turned, may also be used to set a lathe to
turn straight.
CENTER HOLES IN LATHE WORK.
42. Center holes are made in the ends of material (stock) to
fit lathe centers by locating and drilling small holes, then
counter-sinking with a 60 countersink, A and B, Fig. 16.
The countersink should be large enough to provide ample
20
PRINCIPLES OF MACHINE WORK.
bearing to prevent excessive wear, and should be in propor-
tion to the diameter of work.
FIG. 16. STOCK CORRECTLY CENTERED AND PROPERLY MOUNTED ON
LATHE CENTERS.
The drilled hole must be deeper than countersink to pro-
vide a reservoir for oil and to prevent lathe centers from
bottoming, as at C, Fig. 17, as this would injure centers and
VERY BADLY
CENTERED
CENTER HOLE.
VERY BAD
FIG. 17. INCORRECT
CENTERING.
FIG. 18. STOCK CARELESSLY
MOUNTED ON OENTERS.
cause work to run out of true. Center holes must be wiped
clean before mounting on centers. Chips in center holes D,
Fig. 18, will spoil both work and center.
43. To drive the work, dog E, Fig. 16, is fastened to work
by screw F, and tail G must be loose in face-plate slot H.
CENTER HOLES IN LATHE WORK.
21
44. Table of center-hole dimensions. Fig. 19. These
center-hole dimensions provide good bearings for ordinary
lathe work to resist tool pressure.
PLAN TO HAVE THE CENTER HOLES
THE GIVEN DIMENSIONS A
WHEN WORK IS FINISHED TO EXACT LENGTH I '
FIG. 19.
DIAMETER OF
DIAMETER
DRILL SIZE.
DEPTH OF
SHAFT.
SINKS.
NEAREST
64TH.
GAGE No.*
A.
B.
c.
D.
I-A
5
A
56
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52
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52
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42
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22
22
i
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22
i
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/ 5 5yg
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13
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i
Attention. If drill and countersink are within one size they
will answer. . Over 6", countersink may be made J diameter
of work and drill J diameter of countersink.
* Twist drill and steel wire gage.
PRINCIPLES OF MACHINE WORK.
45. Countersinks or center reamers, Figs. 20 and 21, are
made to an angle of 60. They may be made any desired
diameter and with straight shanks, as shown, to be held in
a chuck, or with taper shanks to be inserted in taper collet
or machine spindle. They may have several cutting lips as
in Fig. 20, or but a single cutting lip as in Fig. 21.
60
COUNTERSINK
FIG. 20. FIG. 21.
COUNTERSINKS FOR LATHE WORK.
COMBINATION
COUNTERSINK.
FIG. 22. COMBINED DRILL AND COUNTERSINK.
Combination center drill and countersink, Fig. 22, pro-
duces a countersink central with drilled hole. At end A
drill and countersink are one piece, while at end B a hole is
made in countersink and a center drill inserted and held by a
set screw.
COMBINATION
CENTER DRILL
AND 60
COUNTERSINK
FIG.- 23. COMBINED DRILL, COUNTERSINK, AND COUNTERBORE.
Fig. 23 shows a combination center drill and countersink
of the solid type as at end A, Fig. 22, and in addition a coun-
terboring lip as at C for rounding the corners of the counter-
sink. Combination countersinks of this type are used for cen-
tering mandrels, milling machine arbors and any other work
that is mounted and remounted on centers frequently. Their
use also facilitates the squaring of work.
METHODS OF CENTERING WORK.
23
HAND AND MACHINE METHODS OF CENTERING.
46. Hand method of finding the center, drilling and coun-
tersinking. Figs. 24, 25, 26, 27, 28 and 29.
FIG. 25. DIAGRAM OP APPROXI-
MATE CENTER.
FIG. 24. LOCATING CENTER
OF STOCK WITH DIVIDER
CALIPERS.
FIG. 26. CENTER PUNCHING.
SCHEDULE OF OPERATIONS.
I. Grip stock A, Fig. 24,
in vise B. Smooth ends with file
and rub chalk on ends.
II. Describe arcs with
divider calipers C (shoulder C"
placed on edge of stock) from
four points with radius equal to
about one-half diameter, as at
Fig. 25.
III. Locate center D, Figs. 25
and 26, by eye with center punch
E, Fig. 26. Steady with finger F
and strike with hammer as
shown.
IV. Mount on bench or
lathe centers, revolve and test its
truth with chalk near each end.
If too much out of true, set over
center punch mark as at G, Fig. 27.
Repeat if necessary.
24:
PRINCIPLES OF MACHINE WORK.
FIG. 27. SETTING OVER PUNCH MARK.
SCHEDULE OF OPERATIONS. Concluded.
V. Enlarge center punch
marks with heavier blows before
drilling.
VI. Place drill A in drill
chuck B, Fig. 28, and end of stock
C on dead center. Support with
hand, start lathe, and drill. Use
speed lathe, 3d or 4th speed.
A ttention. Withdraw drill oc-
casionally to let out chips, and
oil into hole. Drill cast iron or
brass dry; on steel or wrought
iron, use oil.
VII. Place countersink D in
drill chuck E, Fig. 29, hold stock
F as before, start lathe and coun-
tersink to desired depth. 1st or
2d speed.
DRILL
A
5
FIG. 28. CENTER DRILLING, HAND METHOD.
FIG. 29. COUNTERSINKING, HAND METHOD.
47. To remove or anneal broken center drill. If the
broken piece of drill does not drop out of hole with the aid of
a scratch awl, strike stock with hammer; if it still remains,
the work must be annealed, and the hole redrilled.
CENTERING MACHINE.
25
48. Machine method of finding the center, drilling and
countersinking. In Fig. 30 is a centering machine used to drill
and countersink center holes accurately in shafts of any length.
FIG. 30. CENTER DRILLING AND COUNTERSINKING. MACHINE METHOD.
CENTERING MACHINE. SCHEDULE OF PARTS AND
OPERATIONS.
A Bed bolted to floor.
B and B' Universal chuck
and operating lever.
C Shows manner of holding
stock to be centered.
D and D f Supports.
E Drill spindle.
F Countersink spindle.
G Center drill.
H Countersink.
J Driving belt.
K Gear mechanism which
drives E and F at different
speeds.
L Handle operating both
spindles.
M Ball lever for tipping head
to bring either spindle into alinc-
ment with stock.
N Stock or work stop for
uniform drilling.
Oil tank.
26 PRINCIPLES OF MACHINE WORK.
Precaution. The end of stock should be approximately
flat and smooth, or the drill will be liable to break.
49. Straightening shafting, rods, and bolts. As soon as
stock is centered, it is mounted on centers and revolved by
hand and its eccentricity tested with chalk. If it is short
or rigid, it may have to be straightened with a hammer on
the anvil; but if slender, it may be straightened on lathe
centers or with straightening press. See Elements of Machine
Work.
CHAPTER III.
CUTTING TOOLS. LATHE TOOLS FOR CAST IRON.
GRINDING LATHE TOOLS.
CUTTING TOOLS.
50. All cutting tools may be considered primarily as
wedges driven into the material to separate it. A thin-
edge tool cuts more easily, because it generates less friction,
distorts the chips less and gives a greater freedom to their
removal. The edge must be thick enough to carry a heavy
cut at a suitable speed, and have a point of sufficient width
to stand the heat generated by friction. Excessive heat/
will soon destroy the point of the tool. This limits the
cutting speeds. A portion of the heat is conducted away
through the work to the air and from point of tool to body
and to air by direct radiation, and on tenacious metal by
the lubricant. See Lubricants for Cutting Tools, 100.
51. Rake, clearance, and cutting angle defined, Rake is
applied to angle of upper surface and clearance to angle of
lower surface. The angle included between these surfaces
is the cutting angle, or angle of
keenness. _FRONT RAKE ~*
52. Front rake, end clearance,
and cutting angle. Fig. 31 is a
side view of a square-nose tool
partially cut by a plane giving a
section CAE. Through point A CLEARANCE
lines AB and AD are drawn par- FIG. 31. DIAGRAM OF FRONT
allel and perpendicular to the base *^ E j^ CE> AND C
line FG. The front-rake angle
is BAC, positive when below and negative when above AB.
The end-clearance angle is BAD. The cutting angle is CAE.
27
28 PRINCIPLES OF MACHINE WORK.
53. Side rake, side clearance, and cutting angle. Fig. 32
is an end view of a right-side tool partially cub by a plane,
giving section K HM. Through point
~"f~ -y^? H H lines HJ and HL are drawn par-
SIDE RAKE -"V, I ^ '/\\r v l ,11 <
allel and perpendicular to the base of
tool NO. The side-rake angle is
vi I J H K. The side-clearance angle
^jtjj MEL. The cutting angle is K HM.
M I * 54. The keenness of a cutting edge
SIDE . .
CLEARANCE is increased or decreased by mcreas-
FIG. 32. DIAGRAM OF SIDE ing or decreasing the rake angle.
RAKE SIDE CLEARANCE, C as t iron mav be cut successfullv
AND CUTTING ANGLE.
with a cutting angle of from 60
to 75 ; steel and wrought iron, with a cutting angle of from
40 to 50. See Brass Turning, 357.
55. Front and side rake combined. For clearness the
front rake and side rake are show^n on separate tools, but some
turning tools will cut more effectively if the top face is given
a combination front and side rake in varying degrees to suit
the nature of the work, as the diamond-point tool, Fig. 45.
56. "Rough turn" and "rough square." Terms used to
name the operations of removing the surplus material from a
piece of metal by one or more roughing cuts preparatory to
finishing.
57. " Finish turn " and " finish square." Terms used to
name the final finishing cuts which reduce any piece of metal to
required size.
LATHE TOOLS FOR CAST IRON.
58. Lathe tools are made of carbon steel and high-speed
steel. See Holders and Cutters, 192, 194 and Elements of
Machine Work.
59. A chart of forged lathe tools is shown in Fig. 33. For
10" to 12" lathes, they are made f " X 1" in section and 7" in
length; for 14" to 16" lathes, i"Xl" section, 9" in length.
Other sizes in proportion. After being forged it is best to file
them to proper shape before they are hardened.
CHART OF FORGED LATHE TOOLS
OUTSIDE TURNING AND THREADING
FACING
OR FRONT
RIGHT LEFT
DIAMOND POINT DIAMOND POINT
CUTTING OFF
BENT
CUTTING OFF
SMALL
ROUGHING
ROUGHING
GROUND FROM BAR
CENTER
TRUING
12
V OR U.S.S.
THREADING
BENT V OR U.S.S.
THREADING
SOUARE
THREADING
BENT SQUARE
THREADING
29
THREADING
BENT 29
THREADING
14
15
16
18
BENT
RIGHT SIDE
BENT FACING
OR FRONT
BENT
ROUND NOSE
BENT RIGHT
DIAMOND POINT
RIGHT HALF
DIAMOND POINT
CENTERING
24 1
LARGE
FINISHING
CUTTING
IN
FORMING
FOR CONCAVE
FORMING
FOR CONVEX
26
27
FORMING
IRREGULAR
30
INSIDE TURNING ANDTHREADING
GROOVING
V OR U.S.S.
THREADING
29
THREADING
36'
FIG. 33.
30
PRINCIPLES OF MACHINE WORK.
60. Right and left tools. A right tool cuts from right to
left and a left tool from left to right. Tools are understood
to be right unless otherwise designated.
61. The angles of lathe cutting tools. In order to select
the proper tool and prepare the correct cutting angle, the
student should consider the kind and, if possible, the hard-
ness of the metal and whether for taking a roughing or finish-
ing cut. If the metal is very hard, the tool must be ground
to a less acute cutting angle, the cutting speed reduced,
or both.
62. Height of tool and tool block. Various devices are
used to regulate the height of the point of the tool. On
FIG. 34. SETTING TOOL HEIGHT OF CENTERS PLAIN REST.
small lathes the rise and fall rest operated by an elevat-
ing screw is perhaps the most common. Fig. 34 shows
a plain rest. The point of tool A is adjusted in tool-post
B to height of dead center C by a tilting action of circular
wedge D in concave washer E and the shank clamped by
screw G.
LATHE TOOLS FOR CAST IRON.
31
63. Round-nose tool. Fig. 35 shows a small round-nose
tool used for roughing and finishing cast iron or brass. Face
A has no rake, but the sides have
10 clearance. The point is about
y thick. B is the cutting edge and
CBD the clearance angle. Too little
clearance will cause the tool to ride
on the work and too much will
weaken the cutting edge. When dull, FIG. 35. ROUND-NOSE TOOL
FOR CAST IRON.
grind end B and a little on top A.
64. To square with round-nose tool. The scale or skin on
cast iron is very hard, and the round-nose tool is used to
rough square ends and remove surplus stock, as in Fig. 36.
Cast iron is machined dry. See Lubricants for Cutting
Tools, 100.
The work is mounted on centers and the lathe run at
proper speed; arrow 1 shows direction of rotation and arrow 2
direction of cut. The long, feed handle is held firmly with
one hand, while the tool is fed with the other operating the
cross-feed handle.
STOCK
CAST-IRON
ROUND NOSE
TOOL
ROUND NOSE
TOOL
FIG. 36. ROUGH SQUARING
CAST IRON.
FIG. 37. ROUGH TURNING
CAST IRON.
65. To turn with round-nose tool. For light rough turn-
ing on small diameters and for finish turning with fine feed, a
round-nose tool may be used to advantage on cast iron, as in
32
PRINCIPLES OF MACHINE WORK.
Fig. 37. Arrow 3 shows direction of rotation of work and
arrow 4 direction of cut. It is sometimes necessary to slant
the tool to the left to turn close to a shoulder or dog, but the
tool must be clamped extra firm or it may draw into the work
and turn the diameter too small.
In Fig. 38 is shown a large round-nose tool for turning or
facing large work. It is ground to shape from the bar and
given side rake as at A, to give freedom to removal of chips.
FIG. 38. TOOL FOR HEAVY
CUTS, ROUGH SQUARING
OR TURNING CAST IRON.
SIDE VIEW
FIG. 39. SIDE TOOL FOR SQUARING
CAST IRON.
66. Side tool. For squaring or facing the ends of shafts,
shoulders, etc., a right-side tool, Fig. 39, is used. The tool
has end clearance B, 15; side clearance C, 10; and side
rake D, 15. The angle E for point F is 60. It is forged
hollow at G, to facilitate grinding. Grinding is done on top
A and end B with a little on side C. Cutting edge HI should
be kept horizontal.
Fig. 40 shows a right-side tool suitable for heavy work.
FIG. 40. SIDE TOOL FOR HEAVY CUTS, SQUARING CAST IRON.
LATHE TOOLS FOR CAST IRON.
33
67. To square an end with side tool. A side tool is set at
the height of the center, as in Fig. 41. On diameters not
larger than f", edge A B is set at right angles to the axis of
work, so as to square the whole end at one cut. For large
diameters the point should " drag " a little, as at A, Fig. 42,
STOCK
RIGHT SIDE
TOOL
FIG. 41. SIDE TOOL SET HEIGHT OF
CENTERS.
FIG. 42. FINISH SQUARING
CAST IRON.
.for both roughing and finishing cuts. The point A being
slightly the deepest, the tool when carried from center to cir-
cumference will produce a smooth surface, provided the tool is
properly hardened, tempered, and ground, and the^speed and
feed are correct. For some purposes, especially in squaring
compositions of brass, a side tool is fed inward.
68. To remove burr around countersink. To remove the
burr that remains around the countersink after taking the
finishing cut, feed the point of tool up to surface of work and
close to dead center; then unclamp binder and relieve dead
center slightly with right hand and at same moment slightly
feed tool inward with left hand, which will remove burr; then
simultaneously feed tool outward and dead center back in
place.
69. Grooved dead center for squaring. The extra opera-
tion of removing burr around countersink when squaring
may be avoided and time saved by using a grooved dead
34
PRINCIPLES OF MACHINE WORK.
center A, Fig. 43. As point of tool B may be started or
terminated in groove, no burr remains.
FIG. 43.
GROOVED DEAD CENTER
FOR SQUARING.
FIG. 44. SQUARING
SHOULDER.
70. To square a shoulder with side tool. To turn a portion
of a piece of stock and square the shoulder, as in Fig. 44, it is
marked as at A, then the cut taken to B, and the shoulder
squared to mark A. The side tool is fed inward to touch the
stock. A moderately fast speed is used and the long, feed is
fed slowly with one hand, while the cross feed is held firmly
with the other; when the cut is carried far enough, the long,
feed is held firmly and the cross feed fed outward.
FIG. 45. DIAMOND-POINT TOOL FOR CAST IRON.
71. Right diamond-point tool. Fig. 45 shows a right
diamond-point tool, A is the top face, which is given a com-
LATHE TOOLS FOR CAST IRON.
35
bination front and side rake, as indicated by arrows B and C.
Side clearance EF is 10, but for a very coarse feed should be
more.
Cast iron of small diameter may be turned by tools without
rake, but for large diameters and heavy cuts a combination
side and front rake of about 15 is effective. The cutting is
done by edge GH and point 7, which should be rounded, as
shown enlarged at I', to strengthen it and produce a smoother
cut. The tool is ground on the top face A, and if necessary,
a little on the side faces.
72. Height of lathe turning tools in relation to axis of work.
The point of taper turning and threading tools must be set at
POINT OF TOOL
HEIGHT OF CENTER
GOOD
FIG. 46. DIAMOND-POINT TOOL SET HEIGHT or CENTERS. GOOD.
height of center, as at FG, Fig. 46. The student may apply
this rule at all times and obtain good results.
73. Evil effects of setting a tool too low or too high. A
tool point set below the center FG } as exaggerated in Fig. 47,
increases the clearance and decreases front rake, will not cut
POfNT OF TOOL
TOO LOW
BAD
FIG. 47. DIAMOND-POINT TOOL
SET BELOW CENTERS! BAD.
FIG. 48. DIAMOND-POINT TOOL
SET ABOVE CENTERS. BAD.
properly, and will dull quickly. A tool point too high above
center FG, exaggerated in Fig. 48, reduces the clearance, will
ride on the work and soon destroy itself by friction.
36
PRINCIPLES OF MACHINE WORK.
74. Theoretical height of turning tools for straight work.
In Fig. 49 is shown the theoretically correct height to set
the point of a tool, which increases its keenness and gives the
greatest support to its cutting edge. This height is at the
tangent point A of line BC, and is located by drawing line DE
through center of work at 90 to line BC. As this gives no
clearance, the tool in practice is set slightly below this point.
After a little training, one is able to set the tool point at
the most suitable height in relation to center FG for any
diameter of work.
HEIGHT OF TOOL POINT
THEORETICALLY CORRECT
FIG. 49. DIAMOND-POINT TOOL SET
THEORETICAL HEIGHT. GOOD.
FIG. 50. ROUGH TURNING
CAST IRON, COARSE FEED.
75. Rough turning cast iron. Fig. 50 shows a diamond-
point tool taking a roughing cut by power long, feed on a
cast-iron piece mounted on centers in an engine lathe. The
chips from cast iron break off in small fragments.
FIG. 51. FINISH TURNING
CAST IRON, FINE FEED.
FIG. 52. FINISH TURNING
CAST IRON, FINE FEED.
76. To finish turn cast iron. Fig. 51 shows diamond
point and Fig. 52 round-nose tool taking finishing cuts (-fa")
GRINDING LATHE TOOLS.
37
with fine feed. Fig. 53 shows small square-nose tool and Fig.
54, large square-nose tool taking finishing cuts (.010") with
coarse feeds.
FIG. 53. FINISH TURNING CAST
IRON, MEDIUM FEED.
FIG. 54. FINISH TURNING CAST
IRON, COARSE FEED.
GRINDING LATHE TOOLS.
77. To grind round-nose tool. Hold at a suitable incli-
nation to give clearance, and first grind the front round by
FIG. 55. GRINDING FRONT OF ROUND-NOSE TOOL.
sweeping shank of tool in an arc of circle, rotating on heel,
Fig. 55. Then grind top as in Figs. 56 or 57.
Warning. Heavy pressure when grinding on a dry wheel
or when the water supply is insufficient, will be liable to draw
the temper and destroy the tool.
38 PRINCIPLES OF MACHINE WORK.
Attention. For Grinding Wheels see 384-397.
For Wet Tool Grinders and Grindstones, see Elements of
Machine Work.
FIG. 56. GRINDING TOP OF ROUND-NOSE TOOL.
FJG. 57. GRINDING TOP OF ROUND-NOSE TOOL ON GRINDSTONE.
FIG. 58. GRINDING POINT OF SIDE TOOL.
GRINDING LATHE TOOLS. 39
78. To grind right or left side tool. First hold tool to
give clearance and angle of point, and grind point, Fig. 58.
Second, hold blade at inclination to give necessary side rake
and grind top face, Fig. 59. Apply pressure and steady with
FIG. 59. GRINDING TOP OF SIDE TOOL.
FIG. 60. GRINDING SIDE FACE OF SIDE TOOL.
left hand. Third, grind side face, Fig. 60. Steady, and
apply pressure with right hand.
40
PRINCIPLES OF MACHINE WORK.
79. To grind right or left diamond-point tool, Fig. 61.
Grind top face, applying pressure with left hand. Then hold
FIG. 61. GRINDING TOP OF DIAMOND-POINT TOOL.
FIG. 62. GRINDING SIDE FACE OF DIAMOND-POINT TOOL.
at angle to give clearance (same for all metals). Steady, and
apply pressure with right hand; grind one side, Fig. 62;
change hands and grind other side. Round point same as
point of round-nose tool, Fig. 55.
80. To grind cutting-off or a Square-thread tool. First
file to shape and width, with proper clearance on sides and
GRINDING LATHE TOOLS.
41
end, harden and temper. Then grind on end and top face
only. Grind end A as in Fig. 63. Steady, and apply
FIG. 63. GRINDING END OF
SQUARE-THREAD OR CUT-
TING-OFF TOOL.
FIG. 64. GRINDING TOP OF
SQUARE-THREAD OR CUT-
TING-OFF TOOL.
FIG 65. GRINDING TOP OF SQUARE-THREAD OR CUTTING-OFF TOOL ON
GRINDSTONE.
pressure with left hand. Fig. 64, B, and Fig. 65, C, show two
methods of grinding top face of any tool of this class.
81. To grind United States Standard or Sharp V- threading tool
FIG. 66. GRINDING SHARP V OR U. S. S. THREAD TOOL.
to fit a gage. File tool to shape, harden and temper. Grind
one bevel, as in Fig. 66. Clean gage and tool, and test angle.
42
PRINCIPLES OF MACHINE WORK.
Grind second bevel; test with gage. If U. S. S. tool, grind
point to fit proper notch in U. S. S. gage. Grind top face.
82. To grind a carbon or high-speed steel removable cutter,
clamp cutter in tool holder, as in Fig. 67, and grind princi-
pally on end and a little on top for rake. For other purposes,
grind cutters similarly to forged tools.
FIG. 67. GRINDING HIGH-SPEED STEEL CUTTER ON A WET
TOOL GRINDER.
FIG. 68. GRINDING HAND GRAVER.
83. To grind graver. Fig. 68. Hold tool at inclination to
produce 60 bevel on end. * Grind the sides a little. See 328.
GRINDING LATHE TOOLS.
43
84. To grind round-nose hand tools, apply them as described
in 77 and illustrated in Figs. 55, 56, and 57.
85. To grind boring tool A, Fig. 69, use corner of wheel to
grind rake B and face of wheel to grind point and clearance.
86. Universal tool grinder. Machine method of grinding
lathe and planer tools, and duplicating angles.
Fig. 70 shows how to grind rake of a right diamond-point
tool. Clamp diamond-point A in holder B. Set three grad-
uated circles, C, D, and E, to readings obtained from chart
WATER
GUARD
I
WET
EMERY
WHEEL
FIG. 69. GRINDING
BORING TOOL.
FIG. 70. DUPLICATING ANGLES OP
LATHE AND PLANER TOOLS.
(chart furnished with machine), or obtain setting by trial.
Move tool to radial face of cup-shaped emery wheel F with
hand wheel G. Carry tool back and forth across wheel with
lever H. Water is supplied from pipe /.
A fourth graduated circle on rear of tool holder, as shown
in detail at K, is used in grinding bent tools.
To grind side faces, revolve holder B and set dials to give
proper angles. To reduce area to be ground, tools may be
44
PRINCIPLES OF MACHINE WORK.
forged in former blocks, or by hand to more clearance than
desired. The method of grinding rake of a right side tool is
shown in Fig. 71. When correct angles and settings of tools
are obtained, they can be accurately duplicated.
Round-nose or circular forming tools are located centrally
with a gage and ground by swinging on a vertical axis. The
top is ground in the usual way.
TOOL
POST
DIAMOND Q
FIG. 71. GRINDING SIDE
TOOL.
FIG. 72. OILSTONING LATHE
TOOLS.
87. To oilstone tools. Use fine manufactured or hard
Arkansas stone about 4" X J X f". Clamp diamond-point
tool A reversed in tool-post B and apply oilstone C as in
Fig. 72, with long strokes. Also oilstone side faces. Use
kerosene oil for manufactured, and lard oil for Arkansas stones.
CHAPTER IV.
SETTING AND USING OUTSIDE CALIPERS. CUTTING SPEEDS,
CUT-METER, AND FEEDS. LUBRICANTS FOR CUTTING
TOOLS. INSPECTING AND MEASURING MATERIAL
(STOCK). OILING AND CLEANING MACHINES.
SETTING AND USING OUTSIDE CALIPERS.
88. To set outside calipers A, Fig. 73, by rule B to length
CD, adjust nut E until lower point coincides with middle
of line D. The width of lines on steel rules is from .002"
. 73. SETTING OUTSIDE CALIPERS.
to .004". A student almost invariably sets outside calipers
large and inside calipers small.
When extreme accuracy is required, such as turning work
to be fitted, the calipers should be set by a standard plug
gage or mandrel, or work of the desired diameter.
45
46
PRINCIPLES OF MACHINE WORK.
89. To measure diameter of lathe work with outside cali-
pers. Fig. 74. Set calipers F to size. Hold work G
stationary and apply calipers at right angles to axis of work
as HI, not as JK or LM. Turn work with tool N until
calipers will pass over it with a light yet distinct touch, but
FIG. 74. MEASURING WITH OUTSIDE CALIPERS.
not hard enough to spring calipers or to sustain their weight.
Usually the calipers have to be passed over work a number
of times to determine this touch.
90. To adjust the tool to turn work to a desired diameter.
Fig. 74. Move tool N inward at end of work to cut under
scale, start lathe and feed tool to cut by hand, then throw in
power long, feed and allow a travel of i". Stop lathe and
test diameter with calipers. If correct, continue turning; but
if too large, start lathe, release power long, feed and run tool
back to end and again slightly advance tool, throw in long, feed
and so on until correct diameter is obtained.
Attention. Hold long, feed firmly with one hand while
releasing power feed with the other.
CUTTING SPEEDS, CUT-METER, AND FEEDS. 47
91. To learn to measure accurately with outside calipers.
Set calipers to rule, turn work until calipers will pass over it
with a delicate touch, then test with micrometer calipers.
92. To transfer a setting from one pair of calipers to
another. Fig. 75. Set inside calipers A to size of hole, then
set outside calipers B by them. Bring lower points of both
calipers in contact and steady as at C, then adjust point D
INSIDE
CALIPERS
FIG. 75. TRANSFERRING MEASUREMENT FROM INSIDE TO OUTSIDE
CALIPERS.
by nut E until it touches point F. To transfer netting of
outside to inside calipers, reverse calipers in hands and adjust
as in Fig. 75.
CUTTING SPEEDS, CUT-METER, AND FEEDS.
93. In turning, three things must be considered :
First, the cutting speed in feet per minute, which is con-
trolled by the diameter of work and speed obtained from the
table; it is calculated or may be directly measured by a cut-
meter.
Second, the depth of cut, one-half the amount that the diam-
eter is reduced.
Third, the feed or amount the tool advances per revolution
of work.
48 PRINCIPLES OF MACHINE WORK.
94. The cut-meter, A, Fig. 76, may be used to measure
cutting speed automatically, also speed of drills, milling cut-
ters, etc. It consists of a case B, which contains the magnetic
mechanism for registration. Scale C is calibrated to read the
CUT-METER
A
FIG. 76. MEASURING CUTTING SPEED.
cutting speed in feet per minute; the line is on glass D. To
use the cut- meter, it is held by handle E and wheel F
pressed against the revolving work G.
95. Surface speed attachment for speed indicator. A rub-
ber-tired wheel A, Fig. 77, 6" in circumference, is slipped over
A point of a speed indicator. See Elements of
Machine Work. The wheel is pressed against
work as at B, Fig. 77, and number of revolu-
tions noted in a given time, as one minute.
To get surface speed in feet, multiply num-
FIG. 77. SURFACE ber of revolutions per minute by 2.
M P E NT D POR E H ; 96. To find the lathe revolutions, given
INDICATOR. the cutting speed and diameter of the work:
Multiply the cutting speed by 12 to reduce it to inches, then
divide by the diameter of the work multiplied by 3.1416.
CUTTING SPEEDS, CUT-METER, AND FEEDS.
49
Example. The work is 2" in diameter and it is desired to
turn it at 35 feet per minute. How many lathe revolutions
are necessary?
OC y 10
2X81416 = 67R - P - M -
97. To find the cutting speed, given diameter of the work
and lathe revolutions per minute: Multiply diameter of work
by 3.1416 and by number of lathe revolutions, then divide
by 12.
Example. The work is 2" in diameter and makes 67 revo-
lutions per minute in the lathe. What is the cutting speed?
2 X 3.1416 X 67
Solution. = 35 feet.
12
98. Eight or ten speeds are possible in an engine lathe.
Place the belt on step of cone that will give the speed near-
est to that required.
TABLE OF LATHE CUTTING SPEEDS.
SPEEDS FOR
ROUGHING.
CARBON STEEL
TOOLS.
HIGH-SPEED STEEL
~TOOLS.
Cast iron
30
60
Steel or wrought iron
25
50
Carbon steel, annealed
Brass composition
20
95
40
190
Speed for finishing is 50% to 100% higher than roughing
speed.
Speed for filing (brass excepted) equals four times roughing
speed.
Speed for filing brass equals three times roughing speed.
Attention. Roughing cuts are not to reduce diameters
more than J"; and finishing cuts, not more than ^$". Rough-
ing feeds are not to be less than 17 revolutions per I" tool
50 PRINCIPLES OF MACHINE WORK.
travel, and finishing feeds are not to be less than 90 revolu-
tions per I" tool travel.
If the above is exceeded, a less speed than that given in
table must be used.
For large diameters, use reduced speed, as the strain on
the tool is greater.
99. Cutting feeds. Lathes with belt feed are limited to
three changes; lathes with gear feed are not limited.
For heavy work, coarse feed is about 17 lathe revolutions
to 1" of tool travel.
For average work, medium feed is about 38 lathe revolu-
tions to V of tool travel.
For average work, fine feed is about 90 lathe revolutions
to I" of tool travel.
For tool making, a feed of 200 revolutions is often used.
Attention. A student may use finer feeds until he acquires
some experience; about 80 to V for roughing and 140 to 1"
for finishing.
LUBRICANTS FOR CUTTING TOOLS.
100. Some metals are machined dry, others require a
lubricant. Cast iron, with about two exceptions, as tapping
and polishing, must be machined dry. Steel and wrought
iron, with two exceptions, as machinery with side or diamond-
point tool (and these are optional), must be machined with
a lubricant. A neglect of this may cause destruction of both
tool and work. See Table of Lubricants, p. 51.
A lubricant on tenacious metal prevents excessive friction
and conducts away heat, thus preserving the point of the
tool and producing a smooth finish on the work. It also
helps to carry away the chips.
Attention. Preferably use sperm oil or lard oil on Arkansas oil-
stones. Use kerosene oil or lard oil on India oilstones.
Oil, " Oil " in tables means lard oil or some oil mixture.
Mixtures and compounds are often used as substitutes be-
cause of cheapness.
Note. Never use mineral oils for cutting tools.
LUBRICANTS FOR CUTTING TOOLS.
TABLE OF LUBRICANTS FOR CUTTING TOOLS.
51
OPERA-
TIONS.
METALS.
CAST
IRON
MACHINE
STEEL, on
WROUGHT
IRON.
CARBON
OR HIGH-
SPEED
STEEL.
COP-
PER.
BRASS OR
BRONZE.
ALUMINIUM.
LEAD.
BAB-
BITT.
Turning.
Boring.
Dry.
Dry. oil or
soda water
Dry or oil.
Milk.
Dry.
Kerosene or
turpentine.
Dry.
Cutting off
Grooving.
Dry.
Oil or soda
water.
Oil or soda
water.
Milk.
Dry.
Kerosene or
turpentine.
Dry.
Screw cut-
ting.
Dry.
Oil.
Oil.
Milk.
Dry.
Kerosene or
turpentine.
Dry.
Threading
with dies
Milk.
Dry.
Kerosene or
turpentine.
Oil.
Tapping.
Oil.
Oil.
Oil.
Drilling.
Counter-
sinking.
Dry.
Oil or soda
water.
Oil or soda
water.
Milk.
Dry.
Kerosene or
turpentine.
Oil. ;
i^c unter
boring.
Chucking.
Dry.
Oil or soda
water.
Oil or soda
water.
Milk.
Dry.
Kerosene or
turpentine.
Dry.
Reaming.
Dry.
Oil.
Oil.
Milk.
Dry.
Kerosene or
turpentine.
Dry.
Milling.
Dry.
Oil, soap
mixture, or
soda water.
Oil, soap
mixture, or
soda water.
Milk.
Dry.
Kerosene or
turpentine.
Dry.
Planing.
Dry.
Dry, oil or
soda water.
Dry or oil.
Milk.
Dry.
Kerosene or
turpentine.
Dry.
Nurling.
Oil.
Oil.
Oil.
Milk.
Oil.
Kerosene or
turpentine.
Dry,
Filing.
Dry.
Dry or oil.
Dry or oil.
Dry or
milk.
Dry.
Kerosene or
turpentine.
Oil,
Polishing
with em-
ery cloth.
Oil.
Oil.
Oil.
Oil.
Oil.
Oil.
Oil.
52 PRINCIPLES OF MACHINE WORK
Soda water (sal soda dissolved in water) is useful in
machining steel or wrought iron, and produces what is known
as a water finish.
Soap mixture. Ib. sal soda, \ pt. lard oil, pt. soft
soap, 10 qts. water; boil one-half hour. This is good for
milling and drilling steel and wrought iron.
101. Drilling extra hard steel such as unannealed carbon
steel. Use a flat drill, with turpentine or kerosene oil as a
lubricant. See 445.
102. Drilling glass. Use a very hard flat drill, scratch
glass with an old file to remove polish and use turpentine as a
lubricant. Drill part way through, then turn over and finish
from the other side to avoid chipping surface.
INSPECTING AND MEASURING MATERIAL (STOCK). OILING
AND CLEANING MACHINES.
103. Inspecting and measuring material (stock). On
receiving a piece of stock, inspect it for imperfections, as
blowholes in castings, flaws (cold short) in forging or bars.
Stock for work to be hardened must be carbon or high-
speed steel. To distinguish high-grade machine steel from
tool steel, a trial piece may be tested by the hardening
process.
Measure piece to see if it is large enough to finish to
dimensions given on the drawing. If the piece be a rough
casting or forging, there should be at least \" surplus stock;
if smooth, T y.
When requested to finish work begun by another, inspect
and measure it, and make a note of its condition, that you
may not be held responsible for errors not your own.
104. Rough turn all over before finishing. As metals
alter in form when the skin or outside is removed, when
possible remove the skin from all surfaces before finishing
any part. An exception is made in some classes of lathe
work, as a shaft which is squared to exact length before
the diameter is roughed out.
OILING AND CLEANING MACHINES. 53
105. Care of machines, small tools, and benches. When
through using a machine, clean it, first with a brush, then
wipe with cotton waste.
Wrenches, handles, bolts, straps, and fixtures should be
put away in their proper places so that they may be found
when wanted. All tools out on checks should be returned
to the tool room as soon as possible.
The bench and vise may be cleaned with a brush. Files
and other tools should be arranged so that they will not
be injured by marring each other and that they may be
readily reached. Be neat, aggressive, and self-reliant.
106. Lathe box or tray for tools and work. Do not place
tools, work, or other metallic objects on the ways of a machine,
as they would scar and affect their truth. A wooden box or
tray should be supplied for the tools or small work. It may
be placed on the ways near the end of the lathe. Large
work should be placed on a bench, truck, or the floor.
CHAPTER V.
ENGINE-LATHE WORK. CENTERING, SQUARING, AND
STRAIGHT TURNING. FILING LATHE WORK.
MICROMETER AND VERNIER CALIPERS.
ENGINE-LATHE WORK.
107. The time element in the schedules is the average for
an experienced workman and includes grinding tools and oil-
ing and cleaning machines. Students and other beginners
will take from 50% to 100% longer on the introductory
problems, and as they become familiar with tools and ma-
ch r nes, from 10% to 25% longer on the advanced problems
depending on the ability of the student and the efficiency of
the equipment and instruction.
108. Schedule of operations, indicated on drawings of
machine parts. To avoid performing work in an improper
order, plan a schedule of operations, machines, and tools for
one or duplicate parts, from the rough stock to the finished
piece. Indicate the operations on drawing by numbers or
letters.
A multiple schedule for two or more duplicate pieces is
the same as for a single piece, except that each operation
is performed on all pieces before beginning the next.
109. The student in machine construction may begin
lathe work by turning soft cast iron, Fig. 78, as it machines
more easily than steel or wrought iron; the cutting angles
of the tools are easy to shape, and the material is not
expensive.
110. To mount work on lathe centers. Clean center holes
and centers with waste. Fasten dog on work (see Fig. 15),
mount on live center. With left hand under end of work,
hold work in line with dead center; move and clamp foot-
stock width of tool block from end of work. Oil dead
center. With the little finger of left hand to guide the
54
ENGINE -LATHE WORK.
55
FIG. 78. CORRECT POSITION AT ENGINE LATHE FOR TURNING.
56
PRINCIPLES OF MACHINE WORK.
dead center into center hole, screw out spindle with the
right hand until there is no end movement. To test ad-
justment, 'move tail of dog back and forth; when right a
slight resistance is felt by the hand; clamp binder.
Warning. When taking a heavy cut or rotating work at
a high speed, the work will heat and expand and thus bind on
the centers. The student should be watchful and relieve
and oil the dead center occasionally. If this is neglected,
a " hot center " will result, which usually destroys both work
and center.
111. To turn work to one diameter from end to end.
First, set tool to take roughing cut and turn approximately
one-half the length (Fig. 79). Stop feed, then stop lathe.
FIG. 79. ROUGH TURNING SHAFT FROM END TO END, FIRST HALF.
Take work out of lathe and run carriage back by hand to
dead center. Do not disturb cross feed. Fasten dog on
turned end A', Fig. 80, with a piece of copper D under set
screw to avoid scarring work. Again mount work on centers
and turn off half marked B' . Regrind tool and follow same
method with finishing cut.
ENGINE-LATHE WORK.
57
FIG. 80. ROUGH TURNING SHAFT FROM END TO END, SECOND HALF.
CENTERING, SQUARING AND STRAIGHT TURNING.
112. To center, square and turn straight. See Figs. 81
and I
i
32.
o I" >,
I
l_
1*
C 8
ROUGH CASTING 11111111
FIG. 81.
SCHEDULE OF OPERATIONS, MACHINES, AND TOOLS.
ROUGHING. FINISHING.
Material, iron casting f" large, weight, 2 Ib. 8 oz., Fig. 81,
free from visible defects.
Oil bearings of lathe with machine oil.
True live center. Set dead center in approximate alinement,
see 40, I.
Use carbon-steel cutting tools. See Exception, p. 59.
Time, to center and square, 20 min.
Time, to rough and finish turn, 25 min*
58
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES, AND TOOLS.
Concluded.
8*
FIG. 82. SCHEDULE DRAWING OF CENTERING, SQUARING AND STRAIGHT
TURNING.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Snag. Center by hand method,
Speed lathe 8" to
Vise, hammer,
46. Center holes ^" diameter,
12". 3d or 4th
chisel, file, chalk,
(1), (2).
speed, or 1400
dividers, rule,
R.P.M.*; coun-
center punch, $%"
tersink 3d speed
drill, 60 counter-
or 700 R.P.M.
sink.
Mount and adjust on centers.
Engine lathe 12"
Dog, round-nose
Rough square (3), round nose in-
to lf>". 2d
. and side tools,
ward, heavy cut, and side tool out-
speed, or 40
15 rake, cali-
ward, light cuts. Reverse work
F.P.M.t Hand
pers, 12" steel
on centers and repeat on (4) . Test
feed.
rule.
length with calipers. Take light
cuts outward on (4) until work
measures 8"+ g"j".
Recenter to ^", (5), (6)
Speed lathe.
60 countersink.
Regrind and oilstone tool and finish
Engine lathe. 3d
Side tool, 15 rake,
square (7) one cut. Reverse work
speed, or 60
calipers, rule.
on centers and repeat on (8).
F.P.M. Hand
Test length with calipers. Take
feed.
light cuts on (8) until work meas-
ures 8". To remove burr around
countersinks, see 68, 69. Test
flatness of end with steel rule.
Rough turn to 1^"+ %" one cut.
1st or 2d speed, or
Copper under set
See Figs. 79 and 80, 111 (9).
25 to 40 F.P.M.
screw of dog,
Test with calipers at ends and
Medium power
diamond-point
middle.
feed 80 to 1*.
tool, 15 rake,
small calipers, 3"
steel rule.
Regrind and oilstone tools. Finish
3d speed, or 55
Diamond-point tool,
turn to I fa", 76, (1O) one cut.
F.P.M. Fine
15 rake, or
Test with micrometer calipers, at
power feed 140
round -nose tool.
both end and middle. Limit al-
to 1".
Calipers, rule
lowed .001". Stamp name on end.
micrometer.
Clean lathe.
Steel name stamp,
machinists' ham-
mer, vise, copper
jaws.
Brush and waste.
* R.P.M. = revolutions per minute. t F.P.M = feet per minute
FILING LATHE WORK. 59
Attention. If necessary, when roughing the tool may be
removed and reground, but in finishing it should be prepared
to carry its cut without regrinding.
Note. When squaring, hold long, feed handle firmly with
one hand while operating cross feed handle with the other.
Caution. As a heavy cut may draw the tool inward,
caliper occasionally and readjust tool, if need be, to avoid
roughing diameter too small.
Exception. If a schedule says " ue carbon-steel cutting
tools" and it is desired to change to "use high-speed steel,"
the cutting speed may be increased from 50% to 100%.
If a schedule says " use high-speed steel cutting tools " and
it is desired to change to " carbon-steel " the cutting speed
must be reduced 25% to 50%.
FILING LATHE WORK.
113. Lathe work is filed to remove tool marks, to make a
fit, to produce an exact diameter, and also to prepare the
surface for polishing. A small amount of filing improves
the condition of the work; excessive or careless filing will
destroy its truth.
114. Mill files are best for lathe work, files single-cut (some-
times called floats), as at C, Fig. 83. A mill bastard is use-
ful for a large variety of lathe filing, but a mill 2d cut is only
used for finer classes of work. See Elements of Machine Work.
115. Speed for filing. If work is revolved at too high a
speed, the file will not bite, but will simply glaze the work and
rapidly destroy itself. As a rule, in filing steel and cast
iron the lathe may be run at a speed between four and
five times faster than that used in taking the roughing cut.
Cast iron must be filed dry. See Table of Cutting Speeds,
98. On brass, the rule is from two to three times the
roughing speed.
On work 1J" and less in diameter, run engine lathe at its
fastest speed. Small work J" and less may be filed in the
speed lathe.
60
PRINCIPLES OF MACHINE WORK.
Warning. To avoid a hot center when filing, loosen and
oil the dead center before and occasionally after increasing
the speed.
116. To hold and to use a file on lathe work. The work
A, Fig. 83, is revolved at a moderately fast speed in the direc-
tion of arrow B. Good results are obtained by moving mill
file C at right angles to the work as at D. If the work to be
filed (A') is a tenacious metal such as machine steel or
wrought iron, hold file at an angle of about 10 as at C f but
move it at right angles as at D f which increases the cutting
angle from 23 to 33. The stroke should be long but slower
FIG. 83. FILING IN LATHE.
than in vise work in order that the work may make a number
of revolutions during each stroke; the pressure should be
lighter, as the number of teeth in contact are fewer.
Note. A file may be moved slightly from left to right; that is, against
its tendency to glide on its forward stroke, but not from right to left as it
may chatter.
Attention. Clean the file frequently with a file card to
remove chips, or they will scratch the work.
117. To finish radial or side surfaces. A hand file is some-
times used, but preferably use a scraper. See 313.
MICROMETER CALIPERS.
61
118. Round and half-round files for lathe work. Fillets
and concave surfaces are generally made with forming tools
and scraped with hand tools. To polish such surfaces, they
may be prepared by filing with round or half-round files, giving
the file on its forward stroke a slight sweep following the curve.
See Lubricants for Cutting Tools, 100.
MICROMETER CALIPERS.
119. The micrometer principle consists of a combination of
an accurate screw and graduated head or nut by which fine
measurements and adjustments may be obtained. It te ap-
plied to feed screws of lathes, planers, milling and grinding
machines, etc., and to instruments of precision, as the microm-
eter caliper, Fig. 84, which consists of frame A and barrel B' }
FIG. 84. MEASURING WITH MICROMETER CALIPER.
in the end of the barrel is a fixed nut through which passes
screw C. The caliper is graduated to read in thousandths of
an inch, but half, quarter, arid tenths of thousandths may be
readily estimated.
120. To measure work with micrometer. Place shaft E
between the faces. Rotate thimble F with thumb and finger
until a light but distinct contact is obtained. Prove results
by moving micrometer up and down on shaft E, or by passing
work between micrometer anvil D and screw C with a slight
rotative motion.
62 PRINCIPLES OF MACHINE WORK.
121. To read micrometer. Screw C has 40 threads to the
inch; the graduations on barrel B are 40 to the inch. One revo-
lution of the screw opens the caliper one-fortieth of an inch,
or .025". Thimble F is graduated into twenty-five parts. Each
division when passing the axial line on barrel indicates one-
twenty-fifth of one-fortieth of an inch (^ X -fa = ToVo")'
Reading. Every fourth division on the barrel is figured
1, 2, 3, 4, etc., and may be read 0.100", 0.200", etc.; the figure
3 may be read 0.300" and the three additional divisions as
0.075", making 0.375" on barrel. Then add the two divi-
sions or 0.002" on the thimble, which makes the complete
measurement 0.377".
Attention. A student occasionally reads the example at
M N backward from zero and obtains .377" instead of .373".
122. Adjusting the anvil to correct error. If zero lines do
not coincide when anvil and screw are clean and in contact,
adjust anvil D by screw G, first loosening screw H.
123. Lock nut K may be used to clamp the screw and
preserve any setting.
124. Speeder and friction slip consists of a ratchet and
pawl used as a speeder for the rapid movement of screw, and
as a friction slip so that the same pressure of contact may be
obtained at every reading.
FIG. 85. MEASURING WORK WITH MICROMETER HELD WITH ONE HAND.
MICROMETER CALIPERS.
63
125. A one-hand method of measuring with a micrometer.
Fig. 85. Hold work A with left hand and insert third finger
of right hand into frame to steady caliper B. Adjust screw C
to work by rotating the thimble with the thumb and first
finger.
126. To measure work in a lathe with micrometer. Fig. 80.
Hold frame A over work B and operate thimble C.
FIG. 86. MEASURING WORK IN THE LATHE WITH MICROMETER.
127. Large micrometer and stand. Micrometer stand A,
in Fig. 87, on bench B, not only protects micrometer C from
MICROMETER
CALIPER
C
FIG. 87. MEASURING WORK ON BENCH WITH MICROMETER.
injury, but avoids expansion due to the heat of the hand.
To measure, hold work D as shown. This micrometer is of
64
PRINCIPLES OF MACHINE WORK.
the interchangeable anvil type. One of the shorter anvils
is shown at F.
Standard end-measuring rods and disks are supplied with
micrometers measuring more than one inch, to test their
accuracy.
128. Decimal equivalents of common fractions. As mi-
crometers are graduated to read decimally, the common
fractions and their decimal equivalents are stamped on the
frames. A student should memorize the decimal equivalents
of such fractions as |", ", 1", ->, ^", and -^" .
TABLE OF COMMON FRACTIONS AND DECIMAL
EQUIVALENTS.
Jv
015625
17
53125
JL
03125
&
046875
35
546875
A
0625
A
078125
A
5625
A
09375
J,
109375
37
578125
i
.125
A
140625
19
59375
A
15625
609375
171875
4
625
fr
1875
|1
640625
&
. 203125
21
65625
A
. 21875
n
671875
M
. 234375
if
6875
i
.250
|i
703125
17
265625
23
71875
A
.28125
47
. 734375
19
296875
J
750
A
3125
42
765625
|1
328125
78125
u
34375
ii
796875
359375
if
8125
4
375
53
828125
390625
27
84375
u
40625
ii
859375
31
.421875
}
.875
A
.4375
**
. 890625
II
.453125
ii
. 90625
. 46875
ii
.921875
484375
if
9375
1
500
li
953125
. 96875
M,
515625
Ix
. 984375
1
1.000000
VERNIER CALIPERS. 65
VERNIER CALIPERS.
129. Vernier prinipcle. Some instruments of precision
have in conjunction with the main rule (or scale) a short
movable scale, called a vernier, to read fractional parts of the
smallest divisions on the main rule.
The vernier is divided into one more or one less divisions
than a given number of divisions on the rule. A division on
the rule thus differs from a division on the vernier by the
fraction shown by 1 divided by the number of divisions on
vernier.
Rule A, Fig. 88, is divided into inches, tenths, and forti-
eths (^Q" = .025"). Vernier B is divided into twenty-five
RULE All 2
234567
1 1 1 ! 1 1 111 I J 1 1 1 1 1 1 1 ill
2 3
4V 5 6 7 8 9
VERNIER B I o 5 IO 15 2O 25
FIG. 88. VERNIER PRINCIPLE,
divisions which equal twenty-four divisions on Rule A. As
each division on rule A is .025" ( V), each division on
Vernier B is .024" or .001" less ( 4 V'X ^V'^ToW " = -001").
If the zero line on vernier is set to coincide with the zero
line or any line on rule A, the next two lines to the^Tight will
differ from each other by .001", and the difference will increase
.001 for each division.
130. Example in reading. First, read the rule. Each tenth
is read .100" and each fortieth .025". The first line on rule
to left of zero line on vernier is distant from zero line on rule
.300" and three fortieths, .075", which gives 1.375".
Second, read vernier. Advancing to the right, we find
that the line at the end of the second division on the vernier
coincides with a line on the rule as indicated by arrows, .002",
is the distance of the zero line on the vernier from the division
on the rule.
Third, to reading of rule add reading of vernier to obtain
complete measurement. Thus: 1.375" + .002" = 1.377".
66
PRINCIPLES OF MACHINE WORK.
131. The application of vernier principle to the vernier
caliper in Fig. 89. Each inch of beam C is divided into 40
parts, and vernier D, attached to sliding head E, into 25
parts. To measure work, as shaft F, the caliper is placed
over the shaft and the sliding head is moved to bring
sliding jaw G and solid jaw H in contact with shaft,
clamp K is fastened to beam by thumb screw L. The
jaws are made to touch shaft delicately yet distinctly by
adjusting nut M, after which head E is fastened to the beam
OUTSIDE MEASUREMENT.
DIAMETER^OF SHAFT F =
1.375"+.002'= 1.377" OR lf'V.002'
INSIDE MEASUREMENT.
DIAMETER OF BORE
. OF HUB P =
1.377"+ .250= I. 627"
OR l|'+.002"
FIG. '89. MEASURING WITH VERNIER CALIPER.
by thumb screw N. The caliper reads the same as the former
example, Fig. 88, that is: 1.377" or If" + .002". It is best
to use a magnifying glass to read or set a vernier caliper.
132. To obtain inside measurements with a vernier caliper.
To take inside measurements, as the bore of hub P shown
dotted, the caliper is read exactly as above, then the width
of the points of the jaws, which differ with the size of the
caliper is added. For the caliper in Fig. 89 two hundred and
fifty thousandths of an inch (0.250") must be thus added to
the reading on the vernier side.
VERNIER CALIPERS. 67
133. Vernier caliper as a caliper square. The vernier
caliper may be used as a caliper square for ordinary outside
and inside measurements by reading the back of beam C,
which is graduated to read to 64ths.
134. A ten-thousandth micrometer. Micrometer calipers
are obtainable to read to the tenth part of a thousandth of
an inch. A vernier of ten divisions is marked on the barrel
A, Fig. 90, and in the space occupied by nine divisions on the
VERNIER THIVBLE
ON BARREL
A
FIG. 90. A TEN-THOUSANDTH MICROMETER.
thimble B. The micrometer reads .250" + . To read the
vernier to obtain the fourth decimal place, locate the line on
the vernier, as line 6, which coincides with a line on the
thimble, and add .0006" to reading, as .250" -f .0006"_= .2506"
or i + .0006".
CHAPTER VI.
FITS IN MACHINE CONSTRUCTION WITH TABLES OF
ALLOWANCES. FORCING PRESS. STANDARD
AND LIMIT GAGES.
FITS IN MACHINE CONSTRUCTION WITH TABLES
OF ALLOWANCES.
135. Fits in machine construction are most important, and
unless made according to requirements, impair the usefulness
of the machine. See Dimension-Limit System, Elements of
Machine Work.
Examples. In an engine lathe the live spindle of steel is a
running fit in bronze or Babbitt boxes in the headstock. The
footstock spindle of steel is a sliding fit in the cast-iron foot-
stock. The headstock cone is a running fit and the head-
stock gear a drive fit on spindle. The headstock, footstock,
and carriage of cast iron are sliding fits on the ways of the cast-
iron bed. See Scraping, Elements of Machine Work.
Like metals are generally used for sliding surface fits,
unlike metals for running fits. Cast iron to cast iron
wears well for any fit, but steel to steel will quickly abrade
unless hardened and ground.
136. The classes of fits used in machine construction are:
running, sliding, driving, forcing and shrinking fits; and taper
fits, running and forcing. The hole or bore for duplicate
work should be standard. See 150.
137. Running fits vary with the class of work. The
amount of looseness varies from .0002" on fine watch work
to -g 1 ^" on some classes of cotton and woolen machinery.
See Tables, Classes I, II, III, page 69. Running fits are often
made taper. The adjustment is obtained by moving the
spindle along the box, or the box along the spindle.
68
FITS IN MACHINE CONSTRUCTION.
69
Running Fits. Class I.
TABLE OF ALLOWANCES AND LIMITS UNDER STANDARD FOR
FINE WORK.
HOLE DIAMETER, INCHES.
SHAFT DIAMETEU =
HOLE DIAMETER
LIMIT SHAFT DIAM-
METER + OR
. 00 to . 49
. 000625
.000125
. 50 to 1 . 99
.0012
. 000375
2 . 00 to 3 . 99
.0016
. 000625
4.00 to 5.99
.002
. 00075
6.00 to 8.00
. 002375
. 000875
Running Fits. Class II.
TABLE OF ALLOWANCES AND LIMITS UNDER STANDARD FOR
AVERAGE WORK WHERE HIGH SPEEDS ARE REQUIRED.
HOLE DIAMETER, INCHES.
SHAFT DIAMETER =
HOLE DIAMETER
LIMIT SHAFT DIAM-
ETER + OR
. 00 to . 49
.001
. 00025
. 50 to . 99
.0015
.0005
1.00 to 1.99
.0019
. 000625
2. 00 to 2. 99
.0023
. 00075
3. 00 to 3. 99
.0027
.00075
4.00 to 5. 99
.0035
.001
6.00 to 8.00
.0038
.00125
Running Fits. Class III.
TABLE OF ALLOWANCES AND LIMITS UNDER STANDARD FOR
ENGINE WORK WHERE EASY FITS ARE REQUIRED.
HOLE DIAMETER, INCHES.
SHAFT DIAMETER =
HOLE DIAMETER
LIMIT SHAFT DIAM-
ETER -f OR
.00 to .49
.0015
.0005
.50 to .99
.002
.00075
1 . 00 to 1 . 99
.0026
.000875
2.00 to 3.99
.0034
.00112.5
4.00 to 5.99
. 00425
.00125
6. 00 to 8. 00
.005
.0015
70
PRINCIPLES OF MACHINE WORK.
138. Sliding fits such as the footstock spindle of lathes are
made similar to running fits except that the final fitting
is done 'by draw-filing. See Elements of Machine Work.
Many lathe manufacturers grind the spindle slightly large,
then force it back and forth in the footstock with a power
press, which smooths, straightens, and stretches the hole,
eliminates wear to some extent and produces a fine sliding fit.
TABLE OF ALLOWANCES AND LIMITS UNDER STANDARD
FOR SLIDING FITS.
HOLE DIAMETER, INCHES.
SHAFT DIAMETER =
HOLE DIAMETER
LIMIT SHAFT DIAM-
ETER + OR
.00 to .49
.0005
. 00025
. 50 to . 99
. 00075
. 00025
1 . 00 to 1 . 99
.00125
. 00025
2.00 to 3.99
.00175
. 00025
4.00 to 5.99
. 00225
. 00025
6.00 to 8.00
.0035
.0005
139. Driving or drive fits, easy and hard are made by
turning the shaft to size with allowance for filing. For easy
fits, file or grind until shaft will enter hole about two-thirds
length of fit with hang! pressure; for hard fits, one-third.
The former are used for light-keyed fits and small work; the
latter for ordinary work which may be removed for repair.
TABLE OF ALLOWANCES AND LIMITS OVER STANDARD
FOR DRIVING FITS.
HOLE DIAMETER, INCHES.
SHAFT DIAMETER =
HOLE DIAMETER +
LIMIT SHAFT DIAM-
ETER + OR
. 00 to . 49
. 50 to 1 . 24
1.25 to 2.49
2.50 to 8.00
.000375
.00075
. 00125
.002
.000125
. 00025
00025
.0005
FITS IN MACHINE CONSTRUCTION.
71
140. Forcing or force fits. In assembling and erecting
machinery, nothing is more important than the proper fitting
of the parts that have to be driven or forced together, or
driven or forced apart, when making repairs. Examples of
forcing fits are gears, couplings, locomotive driving wheels,
crank pins, car axles, rod bushing, crank disks, various kinds
of bushings, linings into cylinders, various parts of engines,
generators and motors, iron bands on wagon-wheel hubs,
crank shafts into automobile fly wheels, various parts of
built-up cranks, or any two machine parts that have to be
joined by forcing one into the other with sufficient power
to prevent them ever becoming loose.
TABLE OF ALLOWANCES AND LIMITS OVER STANDARD
FOR FORCING FITS.
HOLE DIAMETER, INCHES.
SHAFT DIAMETER =
HOLE DIAMETER +
LIMIT SHAFT DI-
AMETER -f OR
. 00 to . 49
. 00075
. 00025
. 50 to . 99
.0015
.0005
1 . 00 to 1 . 49
.0025
.0005
1 . 50 to 1 . 99
.0035
.0005
2. 00 to 2. 49
.0045
.0005
2. 50 to 3. 24
.0055
.0005
3. 25 to 3. 99
.0065
.0005
4. 00 to 4. 99
.0075
."0005
5. 00 to 5. 99
. 0085
.0005
6. 00 to 8. 00
.0095
.0005
Attention. To avoid abrasion and destruction of work,
lubricate both surfaces with machine oil. For heavy work
use cylinder oil, white lead, or grease.
141. Taper forcing fits. For some classes of machinery,
such as marine and engine work, taper forcing fits are used.
The hole is bored to a taper of T y to I", and the shaft ground
or turned the same or to a slightly greater taper, and from
.010" to .020" larger, then forced in.
On some classes of work, the hole is made straight and the
shaft ground or turned to a taper of about .001" to 1", which
makes an effective fit.
72 PRINCIPLES OF MACHINE WORK.
142. Pressures and allowances for forcing fits. Formulas
have been deduced and tables made giving pressures required to
force two parts together; these possess considerable value, but
serve only as a guide, for the pressure required depends not only
on the difference in diameters but on the diameter and length
of fit, smoothness of both parts, material of both shaft and
hub, and diameter of hub. The material will often make a
difference of from twenty-five per cent to fifty per cent in the
pressure for the same allowance. For this reason the method
that is generally followed is to make tables of allowances and
pressures for each class of fits and for different materials.
FORCING PRESS.
143. Forcing presses for forcing fits. The old method of
making forcing fits is with sledge hammers, rams, etc., but
such methods are now nearly obsolete except for occasional
fits, as the'process is difficult, dangerous, and lacks uniform-
ity. The economical, easy, safe, and scientific method is by
hydraulic-power or belt-power presses of which there are a
great variety both vertical and horizontal, small and large,
stationary and portable, to suit all classes of work. Small
forcing fits may be made with a mandrel or arbor press.
144. To force screw into bevel gear. Fig. 91. Belt-
power forcing press. This type of press may be used for
forcing fits between mandrel press work and hydraulic press
work and not requiring a pressure exceeding fifty tons.
Screw A is keyed, lubricated, preferably with linseed oil,
and forced into bevel gear B by ram C, to which motion is
transmitted by gearing actuated by the driving belt D and
controlled by hand wheel E which operates a friction. The
hand wheel E is used to raise and lower the ram and to
control the pressure through its operation of a friction device;
the harder the wheel is turned the greater the friction and the
greater the pressure produced. The friction only acts on
the downward motion.
The plunger F which compresses glycerine in a chamber at
the end of ram C, records the pressure in tons per square
inch by means of gage G,
FITS IN MACHINE CONSTRUCTION. 73
Specifications. The gear in Fig. 91 is steel case-hardened;
hole straight, 1^" diameter; screw, crucible steel; length of
fit, 3"; allowance, and taper, 1.250" in diameter at end and
1.254" at shoulder (ground); pressure, 8 tons.
145. To force shaft into flange, forcing fit. Fig. 92. Belt-
power forcing press. Shaft A is 'keyed, oiled, and forced
into flange B.
Specifications. Flange, cast iron; hole I" diameter; shaft,
machine steel; length of fit, If", straight; allowance, .002"
to .0025", large (ground); pressure, about 3 tons.
Attention. Condition of surfaces (smooth or rough) will
vary the pressure.
146. To force shaft into malleable -iron gear.
Specifications. Malleable-iron gear; hole !-[%" diameter;
length of fit, 2"; shaft, crucible steel; allowance and taper,
1.1875" and 1.1915" at shoulder; pressure, 5 tons.
147. To force shaft into machine -steel gear.
Specifications. Machine-steel gear; hole 2" diameter;
length of fit, 5"; shaft-machine steel; allowance and taper,
2.000" at end, 2.004" at shoulder; pressure, 13 to 15 tons.
148. Shrinking fits are used to fasten a collar, sleeve, crank
pin, crank, or other piece permanently in place. They differ
from forcing fits in manner of fitting only. The fit is made by
heating the hollow piece until it expands sufficiently to go
on the cold shaft easily. The parts must be put together
quickly or the heat will expand the shaft and the parts stick
hard before they are in place, in which case they should be
driven or pressed apart as quickly as possible. When in
place, cool slowly with water.
If the proper shrinkage is allowed, it will not be necessary to
heat piece above a dull red, 800 F.
For small work the hole may be standard and the amount
for shrinkage allowed on shaft.
74
PRINCIPLES OF MACHINE WORK.
FIG. 91. FORCING SCREW INTO BEVEL GEAR. FORCING FIT.
BELT-POWER FORCING PRESS.
FIG. 92. FORCING SHAFT INTO FLANGE. FORCING FIT.
BELT-POWER FORCING PRESS.
FITS IN MACHINE CONSTRUCTION.
75
TABLE OF ALLOWANCES AND LIMITS OVER STANDARD FOR
SHRINKING FITS.
HOLE DIAMETER, INCHES.
SHAFT DIAMETER .=
HOLE DIAMETER +
LIMIT SHAFT DIAM-
ETER + OR
. 00 to . 49
. 00075
. 00025
. 50 to . 99
.0015
.0005
1 . 00 to 1 . 49
.002
.0005
1 . 50 to 1 . 99
.0025
.0005
2.00 to 2.49
.003
.0005
2.50 to 3.24
.0035
.0005
3.25 to 3.99
.004
.0005
4.00 to 4.99
.0045
.0005
5.00 to 5.99
.0055
.0005
6.00 to 8.00
.0075
.0005
149. To shrink tires on wheel centers. Wheel centers
are turned standard and the allowance is made in boring
the tire.
The allowance for shrinkage in rings or jackets for guns in
the United States naval gun factories varies slightly for differ-
ent classes of guns, but it is generally about .001" to the inch.
That is, if the diameter is 12" the shrinkage will be .012".
TABLE OF ALLOWANCES FOR LOCOMOTIVE DRIVING WHEEL
TIRES FOR SHRINKING FITS.
WHEEL CENTER
DIAMETER,
INCHES.
BORE OF TIRE =
WHEEL CENTER
DIAMETER
WHEEL CENTER
DIAMETER,
INCHES.
BORE OF TIRE =
WHEEL CENTER
DIAMETER
38.00
44.00
50.00
.040
.047
.053
56.00
62.00
66.00
.060
.066
.070
150. Standard holes. The holes referred to in tables of
allowances, 149, for the various kinds of fits are either bored
or bored and reamed, and are within limits given in table
of .00025". They are tested by plug and limit gages.
76 PRINCIPLES OF MACHINE WORK.
TABLE OF LIMITS OF HOLE DIAMETERS ALLOWABLE UNDER
AND OVER STANDARD.
HOLE DIAMETER, INCHES. ! LIMIT STANDARD DIAMETER.
+
. 00 to 1 . 24 . 00025
. 00025
1.25 to 2.49
. 00075
. 00025
2. 50 to 5. 99
.001
.0005
6. 00 to 8. 00
.001
.0075
161. Tables of allowances and limits for standard fits,
represent common practice, but are not intended to con-
form to every case that may arise in fitting. In making
allowances for any fit, certain conditions must always be
considered. For example, the allowances for forcing fits are
for cast-iron hubs twice the diameter of machine-steel shafts,
and subject to modifications for different conditions, as the
amount of metal surrounding the hole, the length of hole,
and the elasticity of the metal.
152. To fit by trial and correction, and by allowance. When
only a few pieces have to be fitted, fit by trial. But for
many pieces, fit according to allowance given in tables.
153. To turn and file fits, and to grind fits. Work that was
formerly turned and filed in the lathe is now roughed out with
high-speed steel tools and finished in the grinding machine.
This process produces work quicker, and truer, cylindrically.
See 379.
154. To produce standard fits. Fit ordinary calipers to a
plug gage, reference rod or disk which has the proper allow-
ance. Turn and file or grind shaft to fit caliper. Another
method is to use limit caliper gages directly on work. See
Limit Gages, 162.
155. To produce standard fits with micrometers. Turn
work direct to diameter plus double depth of tool marks; the
allowance for filing with a fine feed and sharp tools is from
.003" to .004*.
STANDARD AND LIMIT GAGES.
77
STANDARD AND LIMIT GAGES.
156. Gages are instruments of reference for standardizing
measurements and for determining dimensions exactly or
within limits.
When a piece is machined nearly to size, a gage is invalu-
ble for determining the exact dimension, the tightness or
looseness of the fit giving an idea of its size.
157. Standard cylindrical gages, ring and plug. Fig. 93
represent an accurate subdivision of the Imperial yard.
FIG. 93. STANDARD RING AND PLUG GAGES.
These gages are made within various limits of accuracy,
such as .0002", .0001", .00005", .00002".
158. Caliper gages, Fig. 94. The measuring faces of the
FIG. 94. CALIPER GAGES.
outside gage are flat, the inside cylindrical. For general use,
this gage is preferred to plug and ring gages.
78
PRINCIPLES OF MACHINE WORK.
159. Reference disk, Fig. 95, is used for testing and setting
calipers.
Attention. As the heat from the hand
will enlarge a gage perceptibly, the body
of gages for very accurate testing is often
covered with a jacket of rubber or wood, or
provided with a hole to receive a wooden
handle, as rubber and wood are poor con-
ductors of heat.
160. End-measuring rod, Fig. 96, for
FIG. 95. STANDARD ' ,.
REFERENCE DISK. g a S m g rm S s > cylinders, setting ordinary
calipers, etc. The ends are sections of
true spheres having diameters equal to the length of the rod.
4"
FIG. 96. STANDARD END-
MEASURING ROD.
FIG. 97. STANDARD END-MEAS
URE TEST PIECE.
161. End -measure test piece, Fig. 97, is used for testing
micrometers, caliper gages and setting tools in planer and
shaper. See Advanced Machine Work.
162. Limit gages are for use in the manufacture of duplicate
pieces of work to save the time necessary in finishing to a
single-gage dimension. They have two fixed dimensions which
differ an amount equal to the limit allowed. See Tables,
FIG. 98. OUTSIDE LIMIT GAGE. FIG. 99. INSIDE LIMIT GAGE.
137, 138, 139, 140, 148, 149, 150. The gages, Figs. 98, 99,
are clearly stamped with dimensions and directions.
STANDARD AND LIMIT GAGES. 79
Adjustable outside limit gages are obtainable which permit
1 he limit to be varied to suit different classes of work.
163. Limit caliper gages for roughing out work are made
from .003" to .01" larger than the maximum diameter of the
finished piece, depending on the class of work.
164. Special gages. Various other standard and special
gages are obtainable.
Attention. Care must be exercised to clean and oil gages
before using and also not to force them into or over work with
undue pressure or they will wear excessively and soon become
unreliable.
CHAPTER VII.
TAPERS IN MACHINE CONSTRUCTION. TAPER TURNING AND
FITTING. TAPER ATTACHMENT. STRAIGHT
TURNING AND FITTING.
TAPERS IN MACHINE CONSTRUCTION.
165. Tapers are expressed as so much per unit of length, as
I" per foot; that is, a piece 1' in length would be 1" larger at-
one end than at the other, as at A and B, Fig. 100. They
FIG. 100. DIAGRAM FOR READING TAPERS.
may be expressed as so much per foot from the center line;
as, \" per foot from center line, \" at A' and 1" at B', the
same taper as 1" per foot. They are also expressed in angular
measurement, see Table of Tapers and Angles, Advanced
Machine Work, as at C, angle of 4 46', or as at C", 2 23'.
166. Tapers, standard and special. Taper parts are used
on nearly all machines. The Morse taper system, approxi-
mately f" per foot (see 656, 657), is used on drills and in
drilling-machine and lathe spindles; the Brown & Sharpe taper
system, \" per foot (see 658, 659), in milling-machine spin-
dles. Both are designated by name and numbers.
The Jarno taper system, .600" per foot, is used to some ex-
tent in lathe and grinding-machine spindles. See 660, 661.
Special tapers are used for spindle boxes, pins, and similar
work.
80
TAPERS IN MACHINE CONSTRUCTION.
81
167. Methods of turning taper. Set over footstock, Fig.
101, or use a taper attachment, Figs. 105, 106. The first
method can only be used for outside tapers; the others can
be used for either outside or inside tapers.
168. To calculate distance to set over footstock. Multiply
one-half taper per foot (in inches) by whole length of work
or mandrel (in feet).
Example. The Morse Taper No. 3, Fig. 101, is .602" per
foot, length of work 8". Find amount to set over footstock.
TAPER. 602" TO 1
B
LOWER PART
FIG. 101. TURNING TAPER WITH FOOTSTOCK SET-OVER.
Solution.
.602
8 13 "
= - 2007 " or '
The distance the centers enter the work affects this rule so
slightly that it is ignored.
169. To set over footstock calculated distance, unclamp
footstock and rotate adjusting screws to move dead center
forward .2007" or JJ", as at A, Fig. 101, measuring lines B
with dividers or rule set to .20". See Table of Footstock Set-
over for Morse, and Brown & Sharpe Tapers. See 662, 663.
82
PRINCIPLES OF MACHINE WORK.
170. To calculate set-over when only length and diameters
are given. Fig. 102.
*
"
t
A
9" 9"
B
6
^Sssssr x
*
4* 2" *
^ 4' 2 "
FIG. 102. EXAMPLE IN LONG TAPER TURNING.
Formula.
Total length
X
Difference in diameters
Length taper portion
= Set-over.
Example. To find set-over; total length 14' I"; tapered
portion 4' 2"; difference in diameter 9" 6" = 3".
Solution. 14' 1" = 169"; 4' 2" = 50".
-Vo 9 - x f = 5.07" (set-over). ,
171. To use a pattern to obtain set-over. If a piece of
taper work has to be duplicated, use it as a pattern to obtain
approximate set-over by mounting it on centers and using a
test indicator. See Tapering Pulleys, 316.
TAPER TURNING AND FITTING.
172. To turn, file and fit Morse tapers No. 3 (.602" to 1'),
Figs. 103 and 104.
7"
3 8
> ur
1
/
FIT TOMORSE STANDARD . y]-
TAPER RING GAGE NO. 3
"T3M4W5W6;
Fio. 103. SCHEDULE DRAWING OP TAPER TURNING? AND FITTING.
FIG. 104. MORSE STANDARD TAPER RING GAGE, No. 3.
TAPER TURNING AND FITTING.
83
SCHEDULE OF OPERATIONS, MACHINES, AND TOOLS.
ROUGHING FINISHING
Material, iron casting J" largo; weight, 2 Ib. 8 oz.
True live center. Set dead center in approximate alinement, see 40.
Use carbon-steel cutting tools. See Exception, p. 59.
Time, 1 h. with blank prepared. Preparation of blank 45 min. extra.
OPERATIONS,
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Snag, center, rough-square, recenter,
Centering machine,
Vise, chisel, file, dog,
finish square. See 48, 112.
Engine lathe, 12"
round-nose tool,
to 16".
side tool, 15 rake.
Strftiffht "turn R,ovisli on.6 cut
Di'imond-point tool,
finish one cut. (Or use blank ma-
15 rake, rule,
chined to 8" X W, Fig. 82.)
calipers.
Copper under set
screw of dog.
T Q-y off iGIlfftll of tl/PCr (l}
Vise rule, scriber,
chalk or copper
sulphate.
Set over footstock to .2007" or |"
2d speed, or 35
Rule, dividers,
as in Fig. 101 or set taper attach-
F. P. M. Me-
diamond-point
ment to approximate taper.
dium power feed
tool, 15 rake,
Set tool height of centers and
80 to 1".
calipers.
rough turn ^f " at small end, one
cut, (2). When within tV' of C,
Fig. 101, release power feed and
use hand feed to within ^" of C.
Grind and oilstone tool. Take a
3d speed, or 50
Round-nose tool,
trial cut about .004" to .005" (3).
F. P. M. Fine
Morse taper ring
Piece will enter gage about 2",
power feed
gage, No. 3, Fig.
enough to determine fit.
140 to 1".
103.
Clean hole and work. Chalk line
Round-nose tool,
along work and test in gage with
Morse taper ring
rotating motion. If chalk line
gage, No. 3, chalk
shows contact throughout by
or Prussian blue.
even rubbing, taper is correct. If
onlv large end bears, set footstock
backward slightly or vice versa,
and take another trial cut. Repeat
above until taper is correct.
Rough turn one cut to f f". (4), or
2d or 3d speeds, or
Diamond-point tool,
until it will reach within -fa" of
35 to 50 F.P.M
15 rake, calipers,
end of gage.
Medium power feed
rule.
Regrind and oilstone tool. Finish
3d speed, or 50
Round-nose tool,
turn one cut to .753" at end +
F.P.M. Fine
1* micrometer.
.004" for filing or until end of
power feed
work comes within T^of end of
140 to I".
gage (5).
Important. Set footstock back in
-
approximate alinement, see 40.
File lightly all over to remove tool
Engine lathe, 4th
8" or 10" mill bas-
marks, (6). Chalk line on work.
speed, or speed
tard file, file card,
Test work in gage, and file bright
lathe, 3d or 4th
Morse taper ring
spots. Continue until fit is uni-
speed, or 105
gage, No. 3,
form and end A is even with end
F.P.M.
1" micrometer,
of gag3, B, Fig. 104, or .753".
chalk or Prus-
sian blue.
84
PRINCIPLES OF MACHINE WORK.
Attention. Set tool to turn taper at exact height of centers. Take
light finishing cuts. Avoid excessive filing. For very accurate work, coat
walls of gage with Prussian blue to test taper.
TAPER ATTACHMENT.
173. To turn taper with taper attachment. Figs. 105,
106. These attachments are applied to engine lathes to turn
s-
VIEW FROM
BACK OF LATHE
FIG. 105. TURNING A TAPER WITH TAPER ATTACHMENT.
FIG. 106. TAPER ATTACHMENT SET TO TURN A TAPER OF f * PER FOOT.
outside and inside tapers. The footstock does not have to
be set over, and the length of the work does not have to be
considered.
TAPER ATTACHMENT.
85
SCHEDULE OF OPERATIONS.
Figs. 105, 106.
Guide bar A is set to turn
taper of drill socket B. Stub
mandrel C provides a center for
hollow end of socket. Guide bar
A carries gibbed sliding block D
which is connected by bolt E to
extension F of supplementary
slide F f which forms the base of
cross slide G. Guide bar is
swiveled upon its base H by
unclamping screws L, L f . Drill
socket B is to have a Morse
taper, No. 4, .625" or I" to 1'.
To Set. Rotate adjusting
screws M, M f until the gradua-
tions on scale at N indicate the
taper. See N', Fig. 106.
Graduations on one end of bar
give a taper of i" to 1',, and on
the other, T V to 1'.
Fasten clamp P by bolt Q and
clamp nuts R, R' on screw S.
Sliding block D and slide T move
with carriage. Guide bar A and
base H remain stationary.
Attention. Take trial cuts
and test in taper ring gage or
in spindle, and make corrections
by adjusting guide bar. See
Taper Fitting, 165-172.
Caution. Take up back lash
before each cut by running car-
riage back at least \" beyond
end of work to avoid turning a
portion at end straight.
Note. To use lathe for
straight work without disturb-
ing taper setting, remove nut R
and move clamp P away.
STRAIGHT TURNING AND FITTING.
174. To turn and file a i" straight running fit.
TO FIT
'STANDARD RING GAGE
FIG. 107. SCHEDULE DRAWING OF STRAIGHT TURNING AND FITTING.
FITTED TO GAGE
RUNNING FIT
FIG. 108. 1" STANDARD RING GAGE.
86
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES, AND TOOLS.
ROUGHING. FINISHING.
Material iron, casting V large; weight, 2 Ib. 8 oz.
True live center. Set dead center in approximate alinement, see 40.
Use carbon-steel cutting tools. See Exception, p. 59.
Time, 30 min. with blank prepared. Preparation of blank 45 min. extra.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
To MAKE FIT BY TRIAL AND CORRECTION.
Snag, center, rough square, recenter
Engine lathe 12" Dog, calipers, rule,
and finish square. See 48, 112.
to 16". round-nose tool,
side tool, 15 rake.
Rough turn 1"+ ^2", one cut, (1),
1st speed, or 25
Copper under set
(or use plain part of blank used
F. P. M. Me-
screw of dog,
for taper turning, 4|" X IjV, Fig.
dium power feed
diamond- point
103).
80 to 1".
tool, 15 rake,
calipers, rule.
Set dead center in accurate aline-
3d speed, or 50 Round-nose tool, 2"
ment to turn straight using this
F. P. M. Fine
micrometer.
piece or trial piece of equal length.
power feed
See 41.
140 to 1".
Rough turn 1" + &", one cut (1).
1st speed, or 25
Diamond-point tool,
F. P. M. Me-
15 rake, calipers,
*"
dium power feed
rule.
80 to I."
Grind and oilstone tool. Oil man-
3d speed, or 50
Round-nose or dia-
drel and push in gage. Set cali-
F. P. M. Fine
mond-point tool,
pers to large end close to gage.
power feed
15 rake, calipers,
Take light cuts at end about "
140 to 1".
1" mandrel, 1"
in length until calipers fit work
ring gage, oil-
slightly harder than on mandrel.
stone.
Oil and try in gage, Fig. 108.
When it enters about $"j" with
hand pressure, wipe off oil and
take cut from end to end by re-
versing work, (2), one cut.
File a small portion at end. Clean
Engine lathe, 4th
8" or 10" mill bas-
and oil work and gage. Try in
speed, or speed
tard file, file card,
gage. Wipe off oil after each
lathe, 3d or 4th
1" ring gage, oil.
trial. Continue fitting over whole
speed, or 110
length in this manner, (3).
F.P.M.
Attention. Test with calipers frequently. Avoid excessive filing.
Test work in both ends of gage, as reamed holes are usually slightly
larger at one end. The lack of oil when testing in gage will spoil both
work and gage.
175. To make a i" running fit by allowance, Figs. 107
and 108.
i 1.002"
Turn to
| 1.003"
:
and
( .9995"
Micrometer calipers
1 .9990"
:::::::::::::::::
CHAPTER VIII.
LATHE TOOLS FOR STEEL OR WROUGHT 1KUJ*. HOLDERS
AND CUTTERS, CUTTING-OFF TOOLS. TURNING STEEL.
LATHE TOOLS FOR STEEL OR WROUGHT IRON.
176. More rake is used on these tools than on those used
for cast iron.
177. Right-side tool. The top face A, Fig. 109, is given a
side rake of about 35 and the side clearance is 10. A lubricant
may be used, but good results are obtained in squaring and
B
FIG. 109. SIDE TOOL FOR SQUARING STEEL OR WROUGHT
turning small work dry. See Lubricants for Cutting Tools,
100.
178. Step method of squaring. To square a rough end or
remove extra length, the step method is used. The side tool,
Fig. 110, is fed inward about T y, then fed by hand long.
STEEL OR
WROUGHT IRON
STEP METHOD
OF SQUARING
FIG. 110. STEP METHOD
OF SQUARING.
FIG. 111. METHOD OP SQUARING
LARGE AMOUNT OF STOCK.
87
88
PRINCIPLES OF MACHINE WORK.
feed. This cuts the first step, as at 1. The process is repeated
at 2, and so on to the countersink. Then a continuous rough-
ing cut is taken outward. When a forging or stock for a
shaft, or spindle, is extra long, the first end is rough squared
in the regular way, and the second end by the step method, as
at A, Fig. 111. The stem left is chipped and filed off. The
stock is recentered and finish squared. If extra length
exceeds f " a cutting-off tool may be used.
179. Right diamond-point tool. For machine steel or
wrought iron the top face A, Fig. 112, is given a combi-
nation of front and side rake of about 35 for roughing or
finishing. For carbon steel
(annealed) it is usually
given less rake, 25 or 30,
and the cutting speed re-
duced.
RIGHT DIAMOND
POINT. TOOL
FOR STEEL OR
WROUGHT IRON
FIG. 112. DIAMOND-POINT
TOOL FOR TURNING STEEL
OR WROUGHT IRON.
FIG. 113. ROUGH TURNING
STEEL OR WROUGHT IRON.
GOOD.
A BAD
ROUGHING CHIP
180. To turn with a diamond-point tool. Fig. 113 shows a
diamond r point tool taking a roughing cut on machinery steel
or wrought iron.
181. Steel or wrought-iron
chips. In Fig. 113 a chip
cut by a tool with 35 rake,
which produces a good sur-
face, is shown, while in Fig.
114 the straight broken chip
is cut by a tool without rake,
which requires more power and leaves a ragged surface.
Only the inexperienced would use a tool without rake for
squaring and turning steel or wrought iron.
RIGHT DIAMOND
POINT TOOL
FIG. 114. ROUGH TURNING STEEL
OR WROUGHT IRON. BAD.
LATHE TOOLS FOR STEEL OR WROUGHT IRON.
89
182. A small roughing tool, substitute for diamond-point, as
in Fig. 115, is often used in roughing and finishing steel or
FIG. 115. ROUGH TURNING STEEL OR WROUGHT IRON.
wrought iron. It may be used for heavy cuts on cast iron.
It is given considerable side clearance, see end view, which
shows at A a section taken at BC. The point is shaped as
shown at D and E.
183. A large roughing tool for steel or wrought iron is shown
in Fig. 116.
FIG. 116. ROUGH TURNING STEEL OR WROUGHT IRON.
90
PRINCIPLES OF MACHINE WORK.
184. Large roughing tool ground from bar. Fig. 117
shows a heavy roughing cut on a piece of tough nickel steel
FIG. 117. ROUGH TURNING STEEL OR WROUGHT IRON.
taken with a large roughing tool made of high-speed steel and
ground from the bar.
FIG. 118. FINISHING STEEL
OR WROUGHT IRON.
FIG. 119. FINISHING STEEL
OR WROUGHT IRON.
185. To finish turn steel or wrought iron. The diamond-
point tool in Fig. 118, with a fine feed, is best adapted to use
LATHE TOOLS FOR STEEL OR WROUGHT IRON. 91
for finishing. To save tirrie, small and large square-nose finish-
ing tools, Figs. 119 and 120, are often used on large work with a
B C
FIG. 120. FINISHING STEEL OR WROUGHT IRON.
lubricant, light cut and coarse feed. The tools drag a little;
that is, the back corners are set to cut deeper than the front
corners to avoid chattering. See A, Fig. 123.
186. Spring finishing tool. Fig. 121 shows a high-speed
STOCK
NICKEL STEEL
FIG. 121. FINISHING STEEL OR WROUGHT IRON.
steel spring tool taking a light finishing cut with a lubricant
on a shaft of nickel steel.
Attention. Broad-nose tools have a great tendency to chat-
ter and produce a rough corrugated surface caused by the long
cutting edge, and made worse by frail, slender work, loose spin-
dle bearings and loose cross slide.
92
PRINCIPLES OF MACHINE WORK.
187. Action of spring tools. Broad-nose finishing tools
have a tendency to dig into the work. The curved portion
of tool in Fig. 121 serves as a spring, and when the cutting edge
is set at the height of center, it will spring away from rather
than into the work when a hard spot is encountered as the
pivoting point is above the center. The success of spring
tools depends upon having the proper amount of spring in
proportion to length of cutting edge and diameter of work.
188. A shear tool, as in Fig. 122, is used} with a lubricant,
to take a light finishing cut on steel or wrought iron.
Square-nose, spring and shear finishing tools should not be
used until one has had considerable experience.
RIGHT DIAMOND
POINT TOOL
FIG. 122. FINISHING STEEL
OR WROUGHT IRON.
FIG. 123. FINISHING STEEL
OR WROUGHT IRON.
For long shafts that are rigid or well supported with a steady
rest, a diamond-point, set as in Fig. 123, will produce an excel-
lent finish either dry or with a lubricant. The cutting edge
drags a little at A.
FIG. 124. LEFT SIDE TOOL FOR STEEL OR WROUGHT IRON.
189. A left side tool is shown in Fig. 124. It is ground
with the same angles as the right side tool and is used for
squaring left shoulders.
LATHE TOOLS FOR STEEL OR WROUGHT IRON. 93
190. A left diamond-point tool is shown in Fig. 125.
is used for turning from left to right.
It
FIG. 125. LEFT DIAMOND-POINT
TOOL FOR STEEL OR WROUGHT
IRON.
FIG. 126. HALF DIAMOND-POINT
TOOL FOB STEEL OR WROUGHT
IRON.
191 . A right half -diamond point tool is sho*vn in Fig. 126. A is
its top face. It can be used to turn up to and to square a shoulder.
HOLDERS AND CUTTERS.
192. Holders with inserted cutters, shown in chart, Fig. 131,
are displacing forged tools to some extent. The cutters are
of high-speed steel. The cutting angles are the same as on
forged tools, and a student should become familiar with forged
tools before using holders and cutters.
193. A straight holder, A, Fig. 127, supplied with a cutter B,
held by screw C, is used as a substitute for a diamond-point
tool.
ROUGHING CUT'
c-
FIG. 127. ROUGH TURNING CHROME- VANADIUM STEEL.
Fig. 129 shows at D, E, and F some uses to which straight
holders and cutters may be put; and Fig. 130 shows some uses
of the right and left bent or offset holders and cutters G and H.
94
PRINCIPLES OF MACHINE WORK.
194. Useful forms of cutters. For convenience, one should
have a number of cutters ground to suitable cutting angles
for different materials and for different operations, as /, J,
K, L, M, N, Fig. 128.
ING or FRONT TOOL ROUND NCSE
L|FT
/ "'BUT ^^
\\
CUTTING OFF TOOL
SQ. THD. TOOL
L
/ -
\ \
\\
MNSIDE
ROUND FORMING OUTSIDE ROUND
(
\
SIDE VIEW
FIG. 128. USEFUL FORMS OF HIGH-SPEED STEEL CUTTERS.
LATHE TOOLS FOR STEEL OR WROUGHT IRON. 95
' Q ' H
FIG. 129. OPERATIONS WITH FIG. 130. SQUARING OR FACING
HOLDERS AND CUTTERS. WITH OFFSET TOOLS.
CHART OF LATHE TOOL HOLDERS
FOR VARIOUS FORMS OF HIGH SPEED STEEL CUTTERS
OUTSIDE TURNING AND THREADING
DIAMOND POINT
ORROUNDNOSE
5
DIAMOND POINT
COMB.HOLDER BENT SWIVEL HEAD RIGHT
ROUGHING DIAMOND POINT DIAMOND POINT SIDE
SWIVEL HEAD
SIDE
CUTTING OFF
BENT
CUTTING OFF
RING
CUTTING OFF
V OR U.S.S.
THREADING
BENT V OR U.S.S
THREADING
M
TJ1F
V
A
11
SQUARE
THREADING
t
DOUBLE
TOOL HOLDER
O
INSIDE TURNING ANDTHREADING
19
20
21
V OR U.S.S.
THREADING
22
SQUARE
THREADING
23
29
THREADING
a i
24
FIG. 131.
96
PRINCIPLES OF MACHINE WORK.
195. Double holder. Fig. 132 shows a " home-made "
double tool holder A, facing both sides of blank B in one
FIG. 132. FACING GEAR BLANK WITH DOUBLE HOLDER AND CUTTERS.
operation. Cutters C, C' are adjusted to cut as desired,
then clamped by screws D, D'.
For duplicate pieces, clamp lathe carriage and use index
pointer on mandrel press to locate blank on mandrel.
196. Two forged tools for facing. Two bent tools A
FIG. 133. FACING GEAR BLANK WITH Two FORGED TOOLS.
and A', Fig. 133, held in two tool-posts B and B / or by a
bolt and strap, may be used to face the sides of gear blank C.
LATHE TOOLS FOR STEEL OR WROUGHT IRON. 97
CUTTING-OFF TOOLS.
197. Cutting-off tool. Fig. 134 shows a cutting-off tool
for all metals. A is its top face. For clearance it is made
A
FORGED
CUTTING OFF
TOOL
B
FIG. 134. CUTTING-OFF TOOL FOR ALL METALS.
wider at the point, as shown. For steel or wrought iron a
lubricant must be used, and the tool is often given front
rake. For cast iron or brass the tool is used dry. The cut-
ting speed is the same as for rough turning.
198. Cutting-off stock. The tool is used close to the chuck
jaws, as in Fig. 135, and should never be used to cut off stock
STOCK
M
FIG. 135. CUTTING-OFF STOCK IN ENGINE LATHE.
more than one diameter of stock away from chuck jaws lest
it catch and break and also strain the chuck. Do not
attempt to sever stock completely, as in Fig. 136, but finish
cutting with a chisel or hack saw. Fig. 137 shows an offset
cutting-off tool holder and cutter.
98
PRINCIPLES OF MACHINE WORK.
FIG. 136. How TO BREAK A CUTTING-OFF TOOL.
FIG. 137. CUTTING-OFF TOOL HOLDER AND CUTTER.
TURNING STEEL.
199. To prepare two shaft blanks, one to turn and file
running and driving fits (Fig. 138), and one to grind run-
ning and forcing fits (Fig. 139).
1 _l9."_'_J
1 Inj RUNNING FIT 1<J 84 ,
._J* l"nmx/c FITI
v ROUGH TURN
'?- 1 t f ;
ROUGH
TURN
1.01.5"
STOCK
MACHINE STEEL
FIG. 138. PREPARING SHAFT BLANK FOR TURNING AND FILING FITS
SCHEDULE DRAWING.
RUNNING FIT
7"
ROUGH TURN
*' 1.078"
i \ t
r;
ROUGH
TURN t*
1.016*
i it
r i 3"
W STOCK (T) (t) (T) C8) ClO) (?) ^
MACHINE STEEL W W V^ V^ k^ V^
FIG. 139. PREPARING SHAFT BLANK FOR GRINDING FITS.
SCHEDULE DRAWING.
TURNING STEEL.
99
MULTIPLE SCHEDULE OF OPERATIONS,
MACHINES, AND TOOLS.
ROUGHING.
Material, machine steel &" to I" large; weight, 2 Ib. 10 oz. each.
Machine dry, or use lard oil.
True live center. Set dead center in approximate alinement, see 40.
Use high-speed steel cutting tools. See Exception, p. 59.
Time, to center and square both shafts, 25 min.
Time, to rough turn both shafts, 35 min.
OPERATIONS.
MACHINES, SPEEDS
FEEDS.
TOOLS.
Center (1), (3), Fig. 138 (1), (2),
Centering machine.
" or No. 43 drill,
Fig. 139 to .
Drill speed, 1200
60 countersink,
R.P.M. Counter-
lard oil.
sink speed, 500
R.P.M.
Rough square (3), (3), then (4), (4)
Engine lathe 12"
Dog, side tool or
to 8&*.
to 16". 2d or
holder and cutter,
3d speed, or 50
35 rake, calipers,
F.P.M. Hand or
rule.
power feed.
Recenter to -fa" and finish square
3d or 4th speed, or
(3), (3), then (4), (4).
80 F.P.M. Hand
or power feed.
Set dead center in accurate aline-
Engine lathe 15"
Dog, copper, dia-
ment to turn straight using this
to 16", 3d or
mond-point tool
shaft or trial piece the same
4th speed, or 70
or holder and
length. See 41.
F.P.M. Fine
cutter, 35 rake,
power feed
micrometer.
140 to 1".
Mark lines approximately equidis-
2d or 3d speed, or
Two dogs with cop-
tant from ends, (5), (5). Rough
60 F.P.M. Med-
per, diamond-
turn to 1.078" (6), (6). Reverse
ium power feed
point tool or
and turn (7), (7). One or two
80 to 1*.
holder and cut-
cuts.
ter, 35 rake, mi-
crometer.
Mark lines at (8), (8).
Copper sulphate,
rule, scriber.
Rough turn (9) , (9) to (8) , (8) . One
2d or 3d speed, or
cut.
60 F.P.M.
Cut recess to fifa" diameter, (10).
1st or 2d speed,
Cutting-off tool,
01 30 F.P.M.
lard oil, calipers,
Hand feed.
rule.
To grind fits, see 419.
To turn and file fits, see 200.
100
PRINCIPLES OF MACHINE WORK.
200. Turning and filing 1" drive fit, (10), (11), Fig. 140.
RUNNING FIT
'*-!
DRIVE FIT |
FIT TO
1 fij" HOLE
LV
FIT TO .
1'HOLE -
SHAFT BLANK V-s fc\ >^\
.MACHINE STEEL ^5/ ^D ^
FIG. 140. SCHEDULE DRAWING.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
FINISHING.
Material, shaft blank machine steel, rough turned 1.015" diameter.
True live center. Machine dry, or use lard oil.
Use high-speed steel cutting tools. See Exception, p. 59.
Time, 25 min.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
To MAKE FIT BY TRIAL AND CORRECTION, (10).
Set dead center in accurate aline-
Engine lathe 15" to
Dog, copper, d i a-
ment to turn straight using this
16". 3d or 4th
mond-point tool,
shaft or trial piece the same
speed, or 70
or holder and cut-
length. 41.
F.P.M. Fine
ter, 35 rake, mi-
power feed
crometer.
140 to 1".
Push mandrel into reamed hole in
3d or 4th speed,
1" mandrel, dia-
work (flange or gear). Set cali-
or 70 F.P.M.
mond-point tool,
pers to large end close to work.
Fine power feed
or holder and cut-
Take several light cuts about "
140 to 1".
ter, 35 rake, cal-
in length until calipers fit work
pers, oil-stone.
slightly harder than on mandrel.
Hold work in vise. Oil shaft and
Vise.
Copper jaws.
press into large end of hole.
When it enters from ^j" to 3^"
with hand pressure, continue cut
(
to shoulder.
Square shoulder, (11).
3d or 4th speed,
Side tool, rule.
or 70 F.P.M.
Hand feed.
File small portion at end. Clean,
Engine lathe, 4th
8" or 10* mill bas-
oil, and press into hole. Continue
speed, or speed
tard, file, file
filing sparingly and testing until
lathe, 1st or 2d
card, oil.
shaft will enter hole one-third
speed, or 175
length of fit. Key ways are cut
F.P.M.
and key fitted before shaft is
pressed or driven to shoulder.
TURNING STEEL.
101
Attention. Hand pressure means grasping dog with both hands, and
pressing shaft hard into hole with a right rotation. A left rotation will
remove it. After each trial, the brightness of the surface and testing
with calipers will indicate where to file. This is often called a wringing fit.
201. To make a V drive fit by allowance, Fig. 140.
( 1 003"
Turnto |l'o04"
::::::::::::::::::
and
( 1 00125" .
Micrometer.
File to j 1 0010(y/
See Belt-power Forcing Press, Fig. 92.
202. To turn and file 1^" running fit, (12), Fig. 140.
Shaft blank machine steel, rough-turned 1.078" large.
Grind tools to 35 rake; machine dry, or use lard oil and
for method of making fit, see 174. For grinding fits, see
419.
Time, 35 min.
CHAPTER IX.
SCREW THREADS. THREADING TOOLS. THREADING
OR SCREW CUTTING. BOLT AND NUT MAKING.
SCREW THREADS.
203. Forms of threads. There are four common forms of
threads: the Sharp V, Fig. 141; the United States Standard,
Fig. 142; the Square, and the Acme Standard or 29 thread.
V THREAD
FIG. 141. SECTIONAL, VIEW OF SHARP V THREAD
U.S. STANDARD THREAD
LEFT
8 THDS.TO 1 IN..FULL SIZE.
l
0.8376"
Fia. 142. SECTIONAL VIEW OF U. S. S. THREAD.
The Whitworth (English) Standard thread, Fig. 161, is very
little used in the United States. It is standard in Great" Britain
for coarse pitches. The British Association Standard thread
is standard for fine pitches. It is similar in form to the
Whitworth, but the angle is 47J degrees. The International
and French Standard threads, used with the Metric system
in some foreign countries, are based on the same formulas as
the United States Standard thread. See 243, 639-641.
102
SCREW THREADS.
103
204. Right and left screw threads. A right screw, Fig.
141, enters its nut when rotated to the right (clockwise). A
left screw, Fig. 142, is the reverse. Screws are supposed to
be right- threaded unless designated left.
205. Uses of different threads. A right Sharp V or United
States Standard thread is used to fasten parts together. A left
thread is also used to fasten parts together, but only where
a rotary motion would loosen a right thread as the nut on the
near side of a wagon axle. The Square and 29 threads both
right and left, are used to transmit motion.
206. Method of threading screws and nuts. Screws for
fine machine parts are threaded in a lathe. Bolts, studs,
and screws are threaded with dies by power and by hand.
See Dies, 539-544.
207. Lead screws, taps, and worm screws may be milled
with a thread milling machine.
208. Small nuts are threaded with a tap by hand or power
FIG. 143. SCREW AND NUT.
(see Taps, 510) ; large nuts are usually threaded in a lathe.
Fig. 143 shows a screw and section of nut.
209. Rolled threads, produced by rolling the material
between moving dies, are used on stove bolts, carriage bolts,
some machine screws, etc.
210. Single and multiple threads. Ordinary screws are
single threaded, but for special purposes screws are double
104
PRINCIPLES OF MACHINE WORK.
threaded, triple threaded, etc. Examine the end of the screw;
if only the end of one thread and one groove is found, it is
single threaded, etc. See Multiple Threads, 622.
211. The pitch of a thread is the distance along the axis of
the work from the center of one thread to the center of
the next, as P, Fig. 141.
212. The lead of a thread is the distance the screw advances
in one revolution. In a single thread, the pitch is equal to
the lead; in a double thread, the pitch is one-half the lead, etc.
213. Threads or pitches per inch signify the number of
threads contained in one inch in length. For example, for
T V pitch we have 10 threads per 1" (often called 10 P).
214. The diameter of threaded work is measured over the
tops of the threads, as 1", Fig. 141.
215. The root or bottom diameter is measured at the root
or bottom of groove, as .7835", Fig. 141.
216. Thread calipers, Fig. 144, may be used to test the
diameter of Sharp V, United States Standard or 29 thread
screws. As the fit is on the sides only the points are filed to
fit the thread gage and are left truncated as at A and A' to
avoid touching the bottom. The calipers are set to size by
means of a thread gage, tap, or screw.
For accurate work, the screw is cut nearly to size of calipers
and the final test is made by trying screw in the nut or work.
FIG. 144. CAUPERING SCREW
WITH THREAD CALIPERS.
FIG. 145. COUNTING THREADS
WITH STEEL RULE.
217. To count threads. Place rule A on thread B, Fig.
145, count grooves in one inch. To count Square and 29
SCREW THREADS.
105
threads, place the end of rule against the right edge of one of
the threads and count the spaces to the right. For double
threads, triple threads, etc., count all the spaces and divide by
2, 3, etc., respectively.
A screw-pitch gage A, Fig. 146, is used to determine number
of threads to one inch on a screw or in a nut. Handle A
D E
FIG. 146. COUNTING THREADS WITH SCREW-PITCH GAGE.
contains many blades notched with all the ordinary threads
to one inch. To determine number of threads to one inch, as
at C, select by trial a blade that will match thread, and the
number at D on blade, as 10, gives number of threads to one
inch on screw. Decimal E is the double depth of a Sharp V
thread of this pitch.
218. The Sharp V thread, Fig. 147. The single depth for
a 1" pitch thread is .866", double depth 1.732". For pitch P,
depth = .866 P = D. Double depth = 1.732 P.
No. of threads per inch'
Root diameter = Outside diameter double depth.
Formula: Root diameter = Outside diameter
1.732
No. of threads per inch
Example. To find root diameter of a
screw 1" diameter, 8 threads per 1".
FIG. 147. SECTION
SHOWING PITCH AND
DEPTH OF SHARP V
THREAD.
Solution.
1-
1.732
.7835.
106
PRINCIPLES OF MACHINE WORK.
219. Table of Sharp V-thread screws.
DIAM-
ETER OF
SCREW.
No. THREADS
PER INCH.
DIAM-
ETER OF
SCREW.
No. THREADS
PER INCH.
DIAM-
ETER OF
SCREW.
No. THREADS
PER INCH.
i
20
!
6
3*
84
18
1
6
3f
3i
*
16
1
5
8|
3i
Tf
14
1
5
3f
3^
%
12
1-,
4
3|
3
ft
12
2
4
3
11
2\
4
4
3
i
11
2
4
4*
2|
10
2
4
4
2}
-
1
10
2
4
4i
2f
1
9
2
4
5
I
9
2|
4
5 i
2^
1
8
4
5^
2i
11
7
7
3
3
3i
8|
6
2i
For Diameter of Tap Drills for Sharp V Threads, see 538.
220. The United States Standard thread, Fig. 148, has its
top and bottom truncated by of the depth, shown by divi-
sions 1, 2, 3, etc., Fig. 142. The single depth of a 1" pitch is. 6495,
double depth is 1.299". For pitch P, depth = .6495 P = D.
Double depth = 1.299 P.
P = pitch
No. of threads per inch '
Root diameter = Outside diameter double depth.
Formula. Root diameter = Outside diameter
1.299
No. of threads per inch
F=Flat=
8
THREADING TOOLS.
107
Example. To find root diameter of a screw I" diameter,
8 threads per 1".
Solution. 1
FIG. 148. SECTION SHOWING PITCH AND DEPTH OP U. S. S. THREAD.
221. Table of United States Standard thread screws.
DIAM-
ETER OF
SCREW.
~
No. THREADS
PER INCH.
DIAM-
ETER OF
SCREW.
No. THREADS
PER INCH.
DIAM-
ETER OF
SCREW.
No. THREADS
PER INCH.
20
If
5*
3|
3i
A
18
1 :
!
5
3*
3i
^
16
1-j
-
5
3f
3i
T^
14
2
4.1
3f
3
1
13
2
4
3&
3
/ &
12
2^
4*
4
3
1
11
2-i
4
4i
2*
f
10
2i
4
4*
2*
f
9
2j
4
41
2f
1
8
2 i
4
5
2*
If
7
3*
5*
^ 2!
if
7
3
3*
5J
2|
If
6
3* '
8*
H
2|
lj
6
33
3*
6
2i
For Diameter of Tap Drills for U. S. S. Thread, see 538.
THREADING TOOLS
222. The forged threading tool, Fig. 149, is forged, hardened,
and then- tempered to a light straw color. The clearance at
F D E is 15, and the cutting edges are GH and JK.
FIG. 149. SHAPE OF SHARP V-THREADING TOOL.
108
PRINCIPLES OF MACHINE WORK.
The top is ground first and then the front faces are ground
to fit center gage and the top is then set at height of center,
as shown in Figs. 150 and 151 at L, M, N and S.
FIG. 150. SETTING THREADING TOOL WITH CENTER GAGE AND TO
HEIGHT OF CENTERS.
223. To set threading tool at height of center and at right
angles to work. Fig. 151.
FIG. 151. SETTING SHARP V-THREADING TOOL AT RIGHT ANGLES
WITH WORK.
SCHEDULE OF OPERATIONS.
1. Turn work P to diameter. 5. Hold gage S as shown.
2. Chamfer end Q depth of Adjust cross feed.
proposed thread. 6. Rap tool around until edge
3. Clamp tool R lightly with TU is parallel to work and about
point 2" from tool-post. &" from it.
4. Adjust point to height of 7. Clamp tool firmly,
dead center (MN, Fig. 150).
224. A special threading tool that may be used straight or
bent to thread to a shoulder, is shown in Fig. 152.
V
THREADING
TOOL
FIG. 152. THREADING TOOL TO CUT TO SHOULDER,
THREADING TOOLS.
109
225. United States Standard threading tool. The United
States Standard thread is cut with a V tool, A, Fig. 153,
A
v.
THREADING
TOOL
A
u.s.s.
THREADING
TOOL
FIG. 153. SHAPE OF U. S. S. THREAD-
ING TOOL BEFORE TRUNCATING.
FIG. 154. SHAPE OF U. S. S.
THREADING TOOL.
truncated at point B, Fig. 154, J depth of thread, which
varies for every pitch. It is ground to fit notch A in U. S. S.
8 THDS. TO I IN.
FIG. 155. GAGE FOR U. S. S. THREAD TOOL.
thread gage, Fig. 155, then truncated at point to fit notch
which corresponds with the threads to be cut, 8, Fig. 155.
The tool is set the same as a Sharp V-thread tool.
Attention. This thread is displacing the Sharp V thread.
110 PRINCIPLES OF MACHINE WORK.
THREADING OR SCREW CUTTING.
226. The theory of screw cutting in the engine lathe. To
thread a screw in a lathe, the threading tool is moved along
the bed a positive and uniform amount for each revolution
of the lathe spindle. This motion is obtained by means of a
train of change gears which connect the lathe spindle to the
lead screw, and by half nuts in the apron which connect the
lead screw to the carriage.
On most lathes the first change gear is on a separate shaft
called the stud. On some lathes this stud is geared to rotate
at the same speed as lathe spindle, and on others at a dif-
ferent ratio.
Ordinary screws may be cut with simple gearing, two
change gears as in Fig. 156. See Compound Gearing, 242. -
227. To calculate simple gearing with spindle gear 1 to stud
gear 1:
Lead screw threads per inch X constant
Threads per inch to be cut X constant
teeth in gear on stud
teeth in gear on lead screw
. The constant may be the common difference in number of
teeth between the consecutive change gears, and this or any
multiplier may be used to obtain available gears.
228. Example. To cut 13 threads to I". Lead screw
5 threads to 1"; speed spindle same as stud; constant, 5.
5X5 25 (gear on stud.)
Solution. = -
13 X 5 65 (gear on lead screw)
Attention. For stud ratios other than 1 to 1, multiply
threads per inch of lead screw by ratio of the stud gear to the
spindle gear and proceed as before.
PREPARATION OF BLANK AND NUT.
Ill
229. Example. To cut 13 threads to I" spindle gear 1 to
stud gear 2, Fig. 156. Lead screw 8 threads per inch;
constant, 6; speed of stud is one-half speed of spindle.
8X2X6 96 (gear on stud.)
-- = . .
78 (gear on lead screw.)
Solution.
13X6
230. A practice screw blank and nut for threading or screw
cutting in an engine lathe, United States Standard or Sharp
V thread, Fig. 156.
""""
FIG. 156.1
PREPARATION OF BLANK AND NUT.
Material, machine steel or wrought iron. Rough and finish
turn portions A and B, Fig. 155, to size for United States
Standard thread, or $" small for Sharp V thread. See Tap-
ping and Threading Sizes, 534. Tap nut C with \" United
States Standard or Sharp V-thread tap. Use lard oil for tapping
or threading.
True live center. Set dead center in accurate alinement.
231. Description of screw-cutting mechanism, Fig. 157.
A Gear on spindle.
B Spindle.
C Gear driven by one or
both idle gears.
D & D' Idlers for reversing.
E Stud driven by C.
F Stud gear.
G Lead screw.
H Lead-screw gear.
K Idler gear, loose on stud.
L Stud.
M Radial arm.
N Bolt to clamp M so that
F drives through KH
toG.
P Reversing lever ; shifts
bracket for cutting right
or left threads.
Q Bracket carrying D and
D'.
Exception. On lathes that do not have reversing gears
D and D', use two idlers to cut a left thread.
112
PRINCIPLES OF MACHINE WORK.
232. To set up lathe for threading or screw cutting. Fig. 157.
SCREW CUTTING
FIG. 157. LATHE SET UP FOR THREADING U. S. S. OR SHARP V
THREAD SIMPLE GEARING, Two GEARS AND AN IDLER GEAR.
SCHEDULE OF OPERATIONS AND TOOLS.
CHANGE OF GEARS, THREADING TOOL, CENTER GAGE,
OIL BOX.
I. Place belt on step 1, screw
face plate 2 hard against shoulder.
II. On blank 3, fasten dog 4
and mark with chalk the place in
face plate where dog is inserted.
(Always return dog to marked
slot or tool will not resume its
cut.)
III. Grind tool 5 to form of
thread desired, U. S. S. or Sharp
V, fasten tool in post 6, and set
with gage, Figs. 149 and 150.
IV. Feed tool in with handle
7 until it touches work, put on
thread stop 8 with screw 9 in
slide 10. Bring stop 8 against
shoulder of 9 and clamp with
screw 11.
V. Set footstock to allow %"
travel of tool beyond work.
VI. From index plate obtain
gears for 13 threads and arrange
as FF' and HH'.
VII. Select gear K for idler.
Preferably a gear nearly the size
of one of the change gears.
VIII. Place stud gear F on
stud E, lead-screw gear H on G.
IX. Place gear K on stud L,
in radial arm M, oil stud.
X. Adjust mesh of H and K
and clamp in position.
XI. Swing radial arm M, to
mesh K with F and clamp with
bolt N.
XII. Be certain that friction
feed is out before throwing in
screw feed.
XIII. Connect lead screw to
carriage 13 by handle S operating
split nut R. Place tin box under
tool to catch chips and drippings.
PREPARATION OF BLANK AND NUT.
113
233. To operate the lathe to cut the thread.
SCHEDULE OF OPERATIONS.
I. Push shipper 14 toward
headstock, adjust stop screw 9 and
move tool 5 to trace a light line ;
stop lathe before tool reaches
end of thread.
II. Finish length of thread by
pulling belt by hand, the first
time only.
III. Move tool out from work.
Run carriage back. Adjust thread
stop screw 9 to take cut.
IV. Count threads, Fig. 158.
Terminate cut by power by eas-
ing tool out when about revo-
lution from end of cut, or point of
tool will snap off.
V. Stop lathe and reverse im-
mediately.
VI. During return, lubricate
work freely with lard oil and ad-
just stop screw 9 for next cut.
VII. Feed tool inward.
VIII. Start lathe forward and
repeat.
SCREW
BLANK
13 THDS.
TO 1 IN.
RULE
DEAD
CENTER
tt
FIG. 158. COUNTING THE TRACE OF A THREAD.
Attention. The cutting speed for threading is about one-
half to two-thirds that used for turning. The feed must be
sufficient to allow tool to cut, for if tool is allowed to travel in
groove without cutting, it will burnish and harden sides of
thread so that on next cut the tool will be likely to dig in and
tear the thread.
Oilstone top face of tool just before taking last few light cuts.
234. Number of cuts for U. S. S. thread, 13 P. Take 8 cuts
of .005" each, 2 cuts of .002" each, then 1 cut of .001"; clean, oil,
and test in nut, and repeat until screw fits nut. Depth of
thread when outside diameter is not reduced = .0499".
235. Number of cuts for Sharp V thread, 13 P. Take 10
cuts .005" each, 2 cuts .002" each, then 1 cut of .001"; clean,
114 PRINCIPLES OF MACHINE WORK.
oil, and test in nut, and repeat until screw fits nut. Depth
of thread when reduced ^V' in diameter = .0588".
236. To fit thread to nut. See 216. Take light cuts
as the thread approaches size, and after each cut clean and
oil thread and try nut on. If a close fit is required, cut thread
until nut will go on easily with a wrench. This smooths down
the burr, after which the nut may go on with the fingers.
For a hard fit, force nut on with a wrench. For a loose fit,
cut the thread until the nut will go on with the fingers. After
thread is fitted, chamfer the end to the depth and angle of
the thread and file tops of thread slightly to remove burr.
237. To reset threading tool to resume cut. If the tool
is dull and thread is only partly cut, remove the tool, regrind
and reset. If the end that receives the dog is cylindrical,
loosen the dog, and rotate the work until tool fits the groove.
Refasten the dog and feed tool away from work, run the lathe
forward a few revolutions, by hand, to take up back-lash; now
notice if tool and groove match; if they do not, repeat opera-
tion. If end of work is square or hexagonal, as a bolt head,
and driven by a clamp dog, disconnect lead screw from lathe
spindle by reversing lever in headstock, or by removing stud
gear, then adjust work.
238. To cut left threads. Arrange gears as in cutting
right threads, with the exception that* the lead screw must
rotate in opposite direction which is accomplished by 'the
reversing gears D, D', Fig. 157, or by an extra idler. At
beginning of thread, cut a groove in which to start tool, and
begin at left and cut to right.
239. To thread to shoulder or to terminate coarse thread.
Cut groove or drill hole of diameter and depth equal to depth
and width of thread. See Figs. 397, 408.
240. Fractional threads. A fractional thread is one whose
threads per inch are expressed by a mixed number, as 11 J
threads to 1"; or a fraction, as f of a thread to I" (1J" P).
To count fractional threads. Take any number of threads
SIMPLE AND COMPOUND GEARING.
115
that will match with even inches on the rule, then divide the
number of threads by the number of inches.
241. To calculate simple gearing to cut fractional threads,
Proceed as for whole threads.
Example. To cut 11 J threads per inch (1" pipe tap).
Lead screw 5 threads per inch; constant, 4; speed of stud
same as speed of spindle.
5X4 20 (gear on stud.)
11^X4 46 (gear on lead screw.)
242. Compound gearing. To cut fine or coarse threads
that are not obtainable with simple gearing, compound the
gearing, using 4 gears, Fig. 159.
FIG. 159. COMPOUND GEARING FOR THREADING, FOUR GEARS.
To compound on some lathes, introduce between regular
stud gear 'A and lead screw gear B two gears of different
diameters, as C and D, which are feather keyed on a sleeve
that runs freely on intermediate stud E, gear A driving gear C,
and gear D driving gear B. The arrangement of gears is
shown in end view at A', C', D', and B'.
243. To calculate compound gearing. Factor first term
into two fractions and treat each separately.
Example. To cut 60 threads per inch.
Lead screw 6 threads per inch; speed of stud same as speed
116 PRINCIPLES OF MACHINE WORK.
of spindle; constant, select multiple of 5, the common differ-
ence between gears.
6 _2X3 2 X 20 _ 40 3 X 10 _ 30
Solution. = 5 x 12 - 5 x 20" 100 ' 12 X 10 ~ 120*
Gear on stud A, 40; gear on lead screw B, 120; first gear on
sleeve C, 100; second gear on sleeve D, 30.
Attention. If more convenient, exchange drivers A and
C or driven C and B.
244. To calculate compound gearing for fractional threads,
proceed as for whole threads.
Example. To cut 2i threads per inch = f .
Lead screw 2 threads per inch; speed of stud same as that
of spindle; constant, multiple of 5.
Solution.
2
3
4
3
X
X
X
X
2
t
25
25
15
15
=
8
9 "
50 )
75 $
60)
45
2
X
4
3X3
one pair of gears. .
other pair of gears.
Attention. It often happens that one or more gears have
to be made or bought. If the threads per inch are expressed
decimally, as 2.833 threads per inch, proceed as before, select-
ing such multiple as will give available gears, using the nearest
whole tooth in case of resulting fractional teeth.
245. Result of gearing calculations may be checked as
follows :
For stud ratio one: Threads on screw to be cut X teeth
of stud gear = threads on lead screw X teeth of lead-screw
gear.
For stud ratios other than one and for compound gearing:
Threads on screw to be cut X teeth of all drivers in succession
= threads on lead screw X teeth of all followers in succession.
SIMPLE AND COMPOUND GEARING. 117
Example. 228 13 X 25 = 5 X 65 = 325.
Example. 229 13X1X96 = 8x2x78 = 1248.
Example. 244 60 X 1 X 40 X 30 = 6 X 1 X 100
X 120 = 72,000.
246. To calculate gearing for a given lead. First change
to threads per inch by dividing one by the lead of screw to
be cut, and proceed as before.
Example. To cut screw |" lead.
Lead screw 2 threads per inch; speed of spindle same as
speed of stud; constant, multiple of 5.
1 3
Solution. - = - (threads per inch).
? 2
2 _ 4 X 10 _ 40
I~3 X 10 = 30*
247. Compound gearing, ratio 2 to i, is provided on some
lathes on an extra adjustable stud. In such cases, gears are
selected as in simple gearing for one-half or twice the desired
pitch, and the 2 to 1 compound arranged to double the pitch
or reduce it one-half.
248. To calculate gearing for metric screw threads with an
English lead screw. Gear up lathe as for cutting a Sharp V
screw of the same number of threads per inch and. use trans-
lating gears. One centimeter equals approximately T \ T of an
inch. Provide lathe with pair of translating gears of 50 and
127 teeth. Arrange lathe as in compound gearing, Fig. 159.
Example. To cut 13 threads to the centimeter.
Lead screw 5 threads per inch; speed spindle same as stud;
constant, multiple of 5.
5X5 25 (gear on stud).
Solution. - = -
13 X 5 65 (gear on lead screw).
Place translating gears on feathered sleeve, meshing 50 with
gear 65 and 127 with gear 25. A metric lead screw may be
used for cutting English threads.
118
PRINCIPLES OF MACHINE WORK.
249. " Catching the thread " (threading without a back-
ing belt). A method to save time in cutting long screws, by
the quick return of the tool carriage after each cut by hand.
If the thread is the same as lead screw or a multiple of it, throw
half-nuts out at the end of each cut, return carriage by hand,
throw in half-nuts, and the tool will resume its cut.
250. General method of " catching the thread." Fig. 160.
FIG. 160, CATCHING THE THREAD.
SCHEDULE OF OPERATIONS.
I. Stop tool A at end of cut B.
II. Chalk tooth in lead screw
gear which is opposite corner
bed C.
III. Chalk tooth in headstock
gear that coincides with front of
headstock D.
IV. Withdraw tool and run
lathe back by hand or power
until tool passes end of work.
V. Run lathe forward to take
up backlash and until chalked
teeth C and D are in same posi-
tion.
VI. Move footstock E to abut
against carriage F, and clamp.
VII. Stop lathe each time tool
is at end of thread, as at B.
VIII. Throw out half-nuts,
return carriage by hand until it
abuts against footstock, and throw
in half-nuts.
Attention. By watching chalk marks before throwing in
half-nuts this method may be used without stopping lathe.
Some lathes are provided with automatic thread stops. The
tool cuts a groove at end of thread, after which lathe is stopped,
half-nuts thrown out, and carriage moved along to a stop
which is clamped on the bed.
THREADING TAPER WORK.
119
251. Threading taper work. Preferably use a taper at-
tachment to cut a thread of correct pitch, as on pipe tap A,
Fig. 161, as footstock "set over" will produce a thread slightly
finer.
FIG. 161. SETTING TOOL TO THREAD TAPER WORK.
Set thread tool 90 to the axis of work as at B, not as at C.
Thread tool D with gage E against shank as at F is correct.
252. Whitworth (English) Standard thread. Figs. 162, 163.
The tops and the bottoms of the 55 threads are rounded,
J of pitch, as shown by divisions 1, 2, 3, etc.
WHITWORTH THREAD
RIGHT
8 THDS.TO 1 IN., FULL SIZE.
P-
0.8399"
FIG. 162. SECTIONAL VIEW
OF WHITWORTH THREAD.
FIG. 163. SECTION SHOWING
PITCH AND DEPTH OF
WHITWORTH THREAD.
The single depth of a 1" pitch is equal to .64033, and the
double depth 1.28066. For pitch P, depth = .64033 P = D.
Double depth = 1.28066 P = 2 D.
No. of threads to 1 inch
R = radius = .1373 P.
Root diameter = Outside diameter double depth.
120
PRINCIPLES OF MACHINE WORK.
Formula. Root diameter = Outside diameter
1.28066
No. of threads to 1 inch
Example. To find root diameter of a screw 1" diameter,
8 threads to 1".
Solution. 1 : = .8399.
253. Table of Whitworth (English) Standard threads.
DIAM-
ETER OF
SCREW.
No. THREADS
PER INCH.
DIAM-
ETER OF
SCREW.
No. THREADS
PER INCH.
DIAM-
ETER OF
SCREW.
No. THREADS
PER INCH.
i
20
If
6
3
3i
18
l
6
3
l,
16
if
5
3
31
A
14
If
5
3-
3 i
2
12
l
4]
1
3;
3
&
12
2
4]
3i
3
|
11
2 i
V
4
3
H
11
2f
4
4i
2i
1
10
2f
4
4^
2|
H
10
2
4
4f
i
9
2f
4
5
2|
it
9
2f
3;
5
2f
i
8
2^
3i
5^-
2f
*i
7
3
3^
5f
2
H
7
3*
3t
6
8*
254. The Whitworth threading tool, Fig. 164. A tool of
different size and shape is required for each pitch. It is made
FIG. 164. SHAPE OF WHITWORTH THREADING TOOL.
similar to a formed cutter by milling. Grind the tool on top
face A. Chasers and single point cutters and tool holders
for Whitworth threads are obtainable.
BOLT AND NUT MAKING.
121
BOLT AND NUT MAKING,
255. The bolt and nut-making operations that follow apply
to all work of this class, as bolts, studs, nuts, and screws.
FIG. 165. TURNING BODY OF BOLT TO HEAD.
To turn up to head of bolt, slant tool to left as at F, Fig. 165,
and clamp tool firmly in tool-post.
FIG. 166. SQUARING BOLT
UNDER HEAD.
FIG. 167. SQUARING BOLT
UNDER HEAD.
To square under head, use right bent side tool G, Fig. 166,
or left side tool H, Fig. 167. To drive from square or hexago-
nal heads use clamp or square dog E, Fig. 165, and to drive
from stem use lathe dog K, Fig. 167.
122
PRINCIPLES OF MACHINE WORK.
256. Nut mandrels. Nuts or similar pieces having tapped
or threaded holes are screwed onto a threaded mandrel and
rough and finish squared to thickness. In Fig. 168 nut B is
screwed on to mandrel A against equalizing collar C, squared
with side tool D, reversed and squared to thickness. It is
then placed onto a milling mandrel and the flats milled in a
milling machine. After this it is replaced on regular nut
mandrel, and side tool E set at 45, as near as can be deter-
mined by the eye, and the edge chamfered as at F to about
FIG. 168. SQUARING AND CHAMFERING NUT.
sV on edge of flats for \" nuts and more or less for larger and
smaller sizes, to give them a neat appearance.
Instead of equalizing collar C, a plain collar G is often used,
with one inside edge rounded to fit over filleted shoulder
of mandrel. For ordinary work, nut mandrels are often
recessed at shoulder and used without collars. Threaded
mandrels, for work threaded while held in a chuck, as a
face plate for a lathe or chuck, need no collar, as the work
is faced true with hole while held in chuck, and this true
face is scr-wed against the shoulder on the mandrel. See
Mandrels, 298.
BOLT AND NUT MAKING.
123
257. Chamfering bolt head, nut, and screws. A clamp
nut (spring or split nut), Fig. 169, is used to protect the
thread and prevent dog from bruising it.
K-
FIG. 169. CHAMFERING AND FORMING BOLT HEAD AND POINT.
SCHEDULE OF OPERATIONS AND TOOLS.
Bolt Heads.
1. Place clamp nut A on bolt B
and fasten dog C with set screw D.
2. Set side tool E at angle
of 45, estimated.
3. Chamfer bolt head to remove
corners and give neat appear-
ance.
Nuts.
Mount nut ou mandrel and
chamfer same
E, F, Fig. 168.
as bolts. See
Screws.
Set side tool F at angle of 30
and chamfer to depth of thread.
To round end of screw G, use
side tool H shaped into a forming
tool.
258. To make a clamp nut, A', Fig. 169.
1. Drill, tap, square and turn ! flat L to receive set screw of
piece of round carbon steel to I dog.
size. 3. Harden and temper to a
2. Slit at K and mill or file
spring temper.
Attention. To make an improvised clamp nut, slit a nut
at a corner with a hack saw.
A clamp nut and dog may be used to set or remove studs.
124 PRINCIPLES OF MACHINE WORK.
259. To make a finished bolt J" diameter. Fig, 170.
13 U.S.S.THDS.TO 1 IN.
|ll RUNNING FIT
= TO 5 IN. STANDARD RING GAGE
CLASS A FINE WORK
STOCK MACH. STEEL
OR WROUGHT IRON
FORGED BOLT BLANK
AND COLD PUNCHED NUT BLANK
FIG. 170. SCHEDULE DRAWING OF A BOLT.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
ROUGHING. FINISHING.
Material, machine-steel or wrought-iron forging, ^" large; weight, 10 oz.
Machine-steel or wrought-iron hexagonal nut blank -fa" large.
True live center, set dead center in approximate alinement, see 40.
Lard oil may or may not be used in squaring and turning steel or
wrought iron.
Use carbon-steel cutting tools. See Exception, p. 59.
Time, 2 h. 10 min.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Straighten and file ends flat.
Vise. Straightening
File, chalk.
press.
Center, machine method, y,
Centering machine
tV drill, 60 counter-
(1,) (2), straierhteu.
drill, 1700 R.P.M.;
sink, lard oil.
countersink, 600
R.P.M.; Straighten-
ing press.
Mount on centers. Rough
Engine lathe 12" to
Regular and clamp
square to 4^ + &*, (3), (4).
16". 3d speed, or
dogs, side tool, 35
Take as little as possible off,
30 F.P.M. Hand
rake, calipers, rule.
(3). See step method of
feed.
squaring, 178.
Recenter to V, (5), (6).
Speed lathe, drill 4th
speed, countersink
3d speed.
Regrind and oilstone tool and
3d speed, or 50
Side tool, 35 rake,
finish square to 4^", (7), (8).
F.P.M.
calipers, rule.
BOLT AND NUT MAKING.
125
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Rough turn to y + 3^" (9)
3dspeedor30F.P.M.
Clamp dog, diamond-
one or two cuts.
Medium power feed
point tool, 35 rake,
80 to I' 7 .
calipers, rule.
Rough square under head, (10).
3d speed, or 30
Left side or bent
F.P.M. Hand feed.
right side tool, cal-
ipers, rule.
Set dead center in accurate
3dspeed,or50F.P.M.
Clamp dog, diamond-
alinement to turn straight
Fine power feed
point tool, 35 rake,
using this holt or a trial piece
140 to I".
1" micrometer.
the same length. See 41.
Rough turn y + &", (9) one cut.
3d speed, or 30 F.P.M.
Clamp dog, diamond-
medium power feed
point tool, 35 rake,
80 to 1".
calipers, rule.
Regrind and oilstone tool, and
3d or 4th speed, or 50
Diamond-point tool,
finish turn to fit gage with
F.P.M. Fine power
35 rake, calipers, y
a lowance for filing, using cali-
feed 140 to I".
mandrel (or 1" mi-
pers, mandrel and gage to ob-
crometer), y ring
tain size; or measure with I"
gage.
micrometer and allow .003"
for filing. (11). One cut.
Regrind and oilstone tool and
3d speed, or 50
Left side or bent right
finish square under head, (12).
F.P.M. Hand feed.
side tool, 35 rake,
calipers, rule.
File to fit gage, running fit.
Engine lathe, 4th
8" or 10" mill bastard
Oil work with machine or lard
speed, or speed lathe
file, calipers,Vstand-
oil when testing in gage. (13.)
8" to 12", 3d or 4th
ard ring gage, oil,
speed, or 175 F.P.M.
1" micrometer.
Chamfer point to 30, (14).
Engine lathe, 3d
Side tool, 35 rake.
speed, or 30 F.P.M.
Hand feed.
Tap y nut blank by hand,
Vise. Engine lathe 3d
y X 13 -U.S.S. tap,
square to thickness, (15).
speed, or 50 F.P.M.
oil, nut mandrel,
Hand feed.
calipers, rule.
Grind threading tool to fit gage,
Engine lathe, 1st
Clamp dog, 13 pitch
and thread bolt to fit nut.
speed, or 20 F.P.M.
U.S.S. thread tool.
Make close fit, see 226, re-
Arrange for 13
center gage, thread
chamfer point, (16), (17). Re-
threads.
calipers, rule, oil,
move gears, empty drip pan
drip (tin) pan.
and clean lathe.
Mill head and nut to size f" +
Milling machine. 3d
Heading mills, index
.003" for filing and polishing,
or 4th speed. Back
head and chuck,
(18), (19).
gears in, or 50
milling machine nut
F.P.M. Medium
mandrel, oil, 1" mi-
power feed.
crometer.
Chamfer head and nut to 45,
Engine lathe, 3d
y X 13 clamp nut,
(20), (21), 256, 257.
speed, or 50 F.P.M.
and nut mandrel,
rule, side tool.
File and polish milled sides of
Vise.
8" or 10" hand-smooth
bolt head and nut only. See
file, nut mandrel,
Elements of Machine Work.
copper jaws, 90 em-
(22), (23).
ery cloth, lard oil.
CHAPTER X.
CHUCKS. FACE PLATES. CHUCKING. REAMING.
CHUCKS.
260. The term chuck has a double meaning. First, it is
the device used for holding work, drills or other tools. Second,
it is the act of securing work in a holding device.
Chucks are indispensable to a large class of work.
261. Attaching chucks to machine spindles. Drill and
other small chucks are attached by a shank, one end fitting
the chuck and the other the hole in spindle. Lathe chucks are
usually attached by a threaded backing plate.
262. Chuck jaws. Four general kinds, Fig. 171:
Drill jaws, for holding drills, rods, and similar pieces, also for
holding hollow work by the inside.
Lathe jaws, for lathe work of large diameter.
Milling-machine jaws, used on milling machines.
Brass (slip) jaws, for brass work.
Reversible jaws. -*- The jaws of some chucks may be
reversed and used either as drill or lathe jaws.
DRILL LATHE MILLING BRASS
JAWS JAWS MACHINE (SLIP)
JAWS
FIG. 171. CHUCK JAWS. FOUR KINDS.
263. Classes of chucks. Drill, independent, universal
and combination, besides draw-in chucks.
126
CHUCKS.
127
264. A drill chuck is used to hold drills and small work.
265. An independent chuck, Fig. 172, is one in which
each jaw is moved independently with wrench. Chuck A
consists of disk B screwed to spindle of headstock C. Lathe
jaws D, stepped to suit different diameters of work, slide in
slots in disk B and are moved by screws E, E, operated by a
special wrench.
Important. Concentric circles are marked on the face of
some independent and combination chucks to facilitate set-
ting jaws and work. ' See Fig. 428.
F INDEPENDENT
CHUCK
FIG. 172. INDEPENDENT CHUCK. FACING DISK.
Attention. Independent chucks are better adapted for
rough work than universal chucks.
266. To true up and hold work in an independent chuck.
Grip work tightly. Run lathe at a moderately high speed,
rest hand on carriage and hold a piece of chalk to just
touch work. Stop lathe, loosen jaw or jaws opposite part
marked by chalk and set others in. Erase chalk mark and
test again, continuing until work runs true, then set all jaws
up hard. Fig. 172 shows also the operation of facing work F
with cutting-in tool G.
128
PRINCIPLES OF MACHINE WORK.
267. A universal chuck, Fig. 173, is one whose jaws move
to and from the center simultaneously and concentrically.
Chuck A is screwed to spindle of headstock B. This is known
as a geared scroll chuck, and is made with either drill jaws, as
shown, or lathe jaws. It consists of shell C, three bevel
pinions E in mesh with an annular bevel gear, upon whose
face is a scroll which engages jaws D. This chuck should be
used for smooth work.
UNIVERSAL
CHUCK
A
FIG. 173. UNIVERSAL CHUCK. TURNING SLEEVE.
268. To true up and hold work in a universal chuck.
Place work in chuck, "set up" jaws by one pinion, run lathe
and use chalk as before. If not true enough, loosen and
turn work about one-quarter of a revolution; tighten pinion
and test again; when right, tighten pinions hard.
Fig. 173 also shows how a bushing is made from bar F.
The bar is squared, then drilled and reamed by chucking
method (see 281. 294), turned with tool G, and cut off with
cutting-off tool.
CHUCKS.
129
269. A combination chuck, Fig. 174, is a chuck in which
the jaws may be moved independently or simultaneously.
When moved simultaneously, jaws may be set either con-
centrically or eccentrically. Chuck A consists of shell B and
jaws C moved by screws D. These screws mesh with thread
on back of jaws, and carry pinions which can be placed in
mesh with an annular bevel gear controlled by device on
back of chuck. When in mesh, chuck is universal; out of'
mesh, each jaw can be moved independently. In Fig. 174
COMBINATION
CHUCK
A
FIG. 174. COMBINATION CHUCK HOLDING AN ECCENTRIC
the jaws are set eccentric with annular out of mesh, then an-
nular is thrown in mesh and the jaws are controlled as in a
universal chuck. To make the chuck universally concentric,
adjust each jaw to a circle on face of chuck and throw in
annular.
270. Special chucks can be made or ordered from a manu-
facturer. For some classes of work, jaws of special shape
may be home-made to fit a regular chuck.
130
PRINCIPLES OF MACHINE WORK.
271. Face plate jaws are obtainable which may be bolted
to a face plate and used as a chuck.
272. Draw-in (spring) chucks, or collets, Fig. 175, are used on
toolmakers' and watchmakers' lathes and also on some engine
and turret lathes to hold bars or rods, as BB'. The rod is
passed through the spindle and accurately held by the chuck,
and from the rod small screws, studs, bolts, etc., may be
conveniently made without preliminary cutting off, centering,
squaring, etc.
FIG. 175. TURNING ROD HELD IN DRAW-IN CHUCK.
The steep taper on the chuck fits the conical hole in end
of spindle. The chuck is slitted a short distance at three
equidistant points, and rotating wheel C, which operates a
hollow shaft that passes through the spindle and makes a
threaded connection to end of chuck, draws the chuck into
its seat to grip the bar or rod.
273. Care of chucks. All chucks, and especially universal
chucks, are short-lived for accurate work unless used intelli-
gently and properly cared for; they should be cleaned and
oiled frequently.
FACE PLATES.
131
274. Mounting and removing chucks. Clean and oil
thread of both chuck and spindle, remove live center and
plug hole with clean waste. Hold chuck square against nose
of spindle with right hand or arm and rotate lathe with
left hand until the chuck comes against shoulder on spindle.
Small chucks may be loosened by grasping one jaw with a
monkey wrench and striking the handle a sharp blow with
the hand; large chucks, by placing a block of wood between a
jaw and the bed of lathe and rotating lathe backward (with
back gears in) by hand. Arbor or shank chucks are inserted
and removed the same as lathe centers.
Attention. To avoid springing work held in a chuck, the
jaws should be forced against the solid parts, if convenient,
as the arms of a pulley.
In some classes of light work, it is often necessary to
loosen the jaws slightly before taking a finishing cut either
when turning work held in a chuck or when boring or
reaming.
FACE PLATES.
275. To hold work on face plate. Some work can be
clamped to a large face
plate and machined more
accurately and conven-
iently than if held in a
chuck. The work B is
clamped to face plate A,
Fig. 176, by clamps C
and C" and bolts D and
D'.
If a finished surface
is to be clamped against
a face plate or other fin-
ished surface, insert a
sheet of paper between FIG. 176. CLAMPING WORK TO FACE
to prevent slipping. PLATE.
132
PRINCIPLES OF MACHINE WORK.
276. To clamp an engine crank to face plate, Fig. 177. To
face plate A crank B is bolted by bolts C and C" and clamp
FIG. 177. TESTING LOCATION OF ENGINE CRANK ON FACE PLATE.
D, in order to bore out hole E and turn and face hub F.
Before clamping to face plate, plane the crank on its face
and line out the holes, as at H and /, Fig. 178. Describe
FIG. 178. LAYING OUT HOLES IN ENGINE CRANK.
circles of the required diameter around the cored holes the
proper distance apart for the crank throw. To provide
centers for circles, drive pieces of wood into holes to form
bridges, as at J and J'. Turn down the corners of a piece
of tin, and drive it into the center of the bridge, as at K and
K'. Rotate lathe by hand and move crank by rapping until
circle is true to axis of rotation when tested with scriber L t
Fig. 177, then clamp crank hard to face plate.
FACE PLATES.
133
277. A counter weight to balance work is bolted to face
plate at M in order to balance the eccentrically placed work
and insure smooth running and accuracy.
278. To hold work with an angle plate. Angle plate A,
Fig. 179, is a useful fixture for various machine tools. It
is planed all over with the faces at right angles (90). It
is bolted to face plate B, and pillow block C is clamped to
FIG. 179. USE OF ANGLE PLATE CLAMPED TO FACE PLATE.
inside surface by bolts D and D' and clamps E and E' '. F is
a counterbalance. Before boring, the pillow block has had
its base planed and the cap fitted and screwed on. A circle
of proper diameter is described around the cored hole and
center punched. The angle plate and work must be adjusted
until this circle runs true, after which hole G may be bored
and reamed.
279. The lathe axis indicator, shown at A in Fig. 180, is
used to test the axial truth of a center punch mark on work
held in a chuck or bolted to a face plate such as the engine
crank shaft center fixture B, which is laid out and marked at
C and D to be drilled, bored, and reamed exactly at these
points.
134
PRINCIPLES OF MACHINE WORK.
The fixture is bolted to the face plate with mark C approxi-
mately central and counterbalance E opposite. The point of
indicating needle F, which is pivoted in the universal joint G, is
placed in center mark C.
FIG. 180. TESTING AXIAL TRUTH OF CENTER PUNCH MARK WITH
INDICATOR.
As the lathe is rotated by hand, the needle point at H will
revolve in a circle, exaggerating the error at C. The fixture is
moved by tapping until needle point H remains stationary,
when the lathe is rotated.
This indicator may be used to locate holes as well as center
marks by first tightening nut K, which converts the universal
into a single joint with a vertical movement, and then placing
spherical head L upon point C, and using it against the upper
wall of the hole. In this way the fixture may be used also
to test the truth of a live center or a shaft turning on centers.
Attention. Paper is sometimes placed between the face
plate and smooth work to prevent the work slipping.
CHUCKING.
280. A method of drilling and reaming. In chucking, the
drill is stationary, while the work rotates. In drilling, the drill
rotates and the work is stationary. Boring is the enlarging
of a hole with a boring tool, or boring bar. Chucking is used
where it would be impractical to drill.
CHUCKING.
135
281. Chucking with twist drill in engine lathe, Figs. 181 and
182.
S7 /
CHUCK
CENTERING
TOOL
, C
FIG. 181. CUTTING A CONICAL CAVITY AXIALLY TRUE
TO START TWIST DRILL.
FIG. 182. CHUCKING HOLE WITH TWIST DRILL.
SCHEDULE OF OPERATIONS AND TOOLS.
Set dead center in approximate alinement.
Drill, T o" to ^V' small. Hand reamer, standard size.
1. Mount work A in indepen-
dent chuck B, Fig. 181.
2. True up work. See 266.
3. Cut cavity of same angle
and diameter as drill, in center
of work to start drill true, with
graver, right side tool or, prefer-
ably, centering tool C, Fig. 181.
4. Fasten dog E to shank of
twist drill D, Fig. 182.
5. Place tool F in tool-post G.
6. Hold tool F against dog E
by long, feed handle with left hand,
to prevent drill feeding away from
center H at end of cut.
7. Feed footstock spindle with
right hand.
8. Help carriage along with
left hand by operating the long,
feed handle.
Warning. To prevent drill D,
Fig. 182, slipping off dead center
H, hold tool F hard against dog E,
To neglect this often ruins drill
and work.
To ream hole, see 294, 295.
136
PRINCIPLES OF MACHINE WORK.
Attention. Solid work, especially steel, is chucked with a
two-lip twist drill. Three and four-groove drills are used for
cored work (castings) or to follow a two-groove drill. Smooth
holes may be made with a drill TIT" to ?V' small and a hand
reamer; but better results are obtained by also using a fluted
chucking reamer .005" small before the hand reamer. See
295.
282. Drill holder and steady rest, A, Fig. 183, is used with
taper shank drills. Rest B and guide bushing C are used to
center, steady, and guide three-groove twist drill D in work
E which is a cored casting held in chuck F. Extra guide
bushings are supplied to fit drills of different diameters.
THREE
GROOVE
TWIST
DRILL
TAPER
SHANK
TWIST
DRILL
HOLDER
.A
FIG. 183. CHUCKING WITH DRILL HOLDER AND STEADY REST.
283. Flat chucking drills for chucking in an engine -lathe,
for either cored holes or solid work, Fig. 184. Large counter-
FIG. 184. FLAT CHUCKING DRILL.
sink A, Fig. 184, provides a firm bearing on dead center.
End B is V smaller in diameter than the chucking reamer.
CHUCKING. 137
Point CC* is central and either thinned or grooved on
both sides, as at D. To give the cutting lips some rake,
grooves may be ground above them, one of which is shown
3
E 1
FIG. 185. GROOVED-LIP FLAT CHUCKING DRILL.
at EE', Fig. 185. A better way is to twist the lips as at F and
G, Fig. 186.
H
FIG. 186. TWISTED-LIP FLAT CHUCKING DRILL.
284. Flat chucking reamers, Fig. 187. The cutting edges
are AB and CD. Head E is from .005" to .010" under size
to allow for hand reaming.
D
FIG. 187. FLAT CHUCKING REAMER.
Attention. Reamed holes have a very slight taper and the
end the reamers enter is always the larger; therefore drill and
ream work from the side into which the shaft is to be fitted.
285. Chucking with a flat drill and chucking reamer in an
engine lathe. Fig. 188.
138
PRINCIPLES OF MACHINE WORK.
FIG. 188. CHUCKING PULLET WITH FLAT DRILL.
SCHEDULE OF OPERATIONS AND TOOLS.
Set dead center in approximate alinement.
Drill, sV to ^V small. Chucking reamer, T -V small.
Drill rest. Monkey wrench. Hand reamer, standard size.
1. Mount pulley A in inde-
pendent chuck B.
2. True up by inside of rim.
3. Clamp drill holder C in post
E to tool block F.
4. Set holder with dead center
H' exactly in middle of slot as
at G and with drill approximately
central as C", D'.
5. Set holder near work as at
C", A'.
6. Place point of drill central
against hub A'.
7. Place dead center H in other
end.
8. Pull wrench K forward to
pinch drill in slot.
9. Start lathe at speed for
twist drills.
10. Feed spindle until drill cuts
half the depth of its point.
11. Remove wrench. Feed
drill rapidly.
12. Hold drill back on dead
center with left hand, when point
breaks through.
13. Stop lathe when through.
14. Place flat chucking reamer
in slot as in operation 4.
15. Hold with wrench until
reamer is started. When through
stop lathe. To ream hole, see
289, 293, 294.
Attention. If slot in holder is
not at height of dead center, the
drill or reamer will cut large and
may spoil work. If drill moves
sidewise when starting, replace
wrench and repeat. Drill must
cut true before reaching full diam-
eter. For Targe holes or cored
holes, use two or three flat drills
of increasing diameters.
REAMING.
139
REAMING.
286. Reamers are used for sizing, smoothing, and standard-
izing straight and taper holes. See Taper Reamers, 297, and
Advanced Machine Work.
There are two general classes: chucking or roughing ream-
ers, used in a machine, and finishing reamers, used by hand or
power. The usual amount for the finishing reamers to cut
is .005" to sV' for cast iron, and .005" to .010" for steel and
brass.
287. Irregularly spaced teeth. To prevent chattering,
reamer teeth or blades are spaced progressively wider as in
Fig. 189, A to 1 to the right, and from 1 to A to the left.
The clearance G is given the teeth or lands to relieve the
cutting edge. The point of a hand reamer is slightly tapered
a distance equal to its diameter, to enter the hole. The shank,
H, Fig. 191, is ground .001" small, to prevent binding in hole.
4
3 "
FIG. 189. TEETH OF HAND
REAMER IRREGULARLY
SPACED.
FIG. 190. TEETH OF HAND
REAMER WITH NEGATIVE
RAKE.
238. To ream brass, the face of teeth is inclined 20 back
of radial (negative rake) to prevent chattering, as in Fig. 190.
See Broaching, Advanced Machine Work.
Attention. Cast iron and brass are reamed dry; steel and
wrought iron with oil.
Warning. To ream thin work in a vise use a jig similarly
constructed to the tapping jig, 528. To ream work in a
140
PRINCIPLES OF MACHINE WORK.
vise without a jig and also without chattering and spoiling the
work, the length of hole should be about twice the diameter of
the reamer. See 293.
FIG. 191. REAMING IN VISE.
289. Hand reaming work held in vise. Fig. 191.
SCHEDULE OF OPERATIONS AND TOOLS.
Hole in flange casting drilled or drilled and reamed .005" to ^V small.
1. Chuck work B in engine
lathe then fasten firmly in vise C.
2. Place adjustable reamer
wrench D on square end of
reamer A and fasten with thumb
screw E.
3. Rotate wrench rapidly in
direction of arrow F and at same
time press downward in direction
of arrow G, continue rotating and
pressing downward until reamer
passes clear through the casting.
Attention. Hand reamers should never be rotated back-
ward as it quickly destroys their cutting edges, and they should
be used vertically when the nature of the work will permit.
Note. Before placing reamer in hole, see that there are no
burrs on shank H, which would be likely to scratch the reamed
surface as the reamer is passed through the hole.
REAMING.
141
290. To ream a hole by hand in a vertical drilling machine,
Fig. 192.
SPINDLE
FIG. 192. HAND REAMING IN A VERTICAL DRILLING MACHINE.
SCHEDULE OF OPERATIONS AND TOOLS.
Hole in work drilled .005" to small.
1. Place drill in socket and the
socket in spindle.
2. Unclamp table at swivel and
column.
3. Adjust table until drill will
pass down through any con-
venient hole and reclamp.
4. Clamp block A to table B
with clamps, bolts, and step
blocks Q C'.
5. Drill hole with reamer drill.
See Accurate Drilling, 462-470.
6. Insert center D and place
wrench E and reamer F in place.
7. Rotate reamer in direction
of arrow, following with center D.
291. Adjustable reamers. A, Fig. 193, may be adjusted
to compensate for wear and to ream special-size holes.
292. Reaming stand B, Fig. 193, is more convenient than
a vise. It consists of an independent chuck C, supported
by column D. The work E is firmly gripped in the jaws F
by operating the handle G.
142
PRINCIPLES OF MACHINE WORK.
FIG. 193. HAND REAMING IN REAMING STAND.
293. To ream work by hand in the lathe with a hand reamer,
Fig. 194.
FIG. 194. REAMING IN LATHE BY HAND.
REAMING.
143
SCHEDULE OF OPERATIONS AND TOOLS.
Hole in blank drilled or bored .005" to ^V small.
Set dead center in approximate alinement.
1. Place reamer A in drilled
or bored hole in work B held in
chuck C.
2. Place arm of wrench D
against tool block E.
3. Pull belt downward and
follow with dead center.
Attention. Carefully follow reamer with dead center to
prevent spoiling reamer and work.
On thick work, start hand reamer in above manner in lathe,
and then take both work and reamer to reaming stand or
vise for finishing. See 289.
294. Fluted chucking reamer, Fig. 195, is obtainable in
standard sizes or .005" small, to be followed by standard
hand reamer. This class of reamers has its points always
beveled, and some points are slightly tapered the same as on
hand reamers. Chucking reamers are also obtainable with
taper shanks to fit drill sockets.
295. To ream in lathe by power with fluted chucking reamer,
Fig. 195. Fasten dog D to shank of reamer A and insert
reamers in drilled hole of work B, held in chuck C, allowing
dog D to rest on tool block E.
FIG. 195. REAMING GEAR BLANK IN LATHE BY POWER.
144
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS AND TOOLS.
Hole in casting drilled T ^/' to ^V small.
Set dead center in approximate alinement.
1. Place reamer A in drilled
hole in work B held in chuck C.
Fasten dog D to shank of reamer
and rest on tool block E.
2. Fasten tool F in post G and
adjust to prevent reamer drawing
off dead center.
3. Use power and help carriage
along by hand. Use about two-
thirds the speed recommended
for twist drills of same diameter.
Warning. To prevent reamer
A, Fig. 195, slipping off dead cen-
ter, press tool F hard against dog
D. Neglect of this often ruins
drill and work.
To hand ream, see 293.
296. Rose chucking reamer, Fig. 196, is made with either
straight or helical flutes, with cutting teeth on end only. It
will not produce as smooth a hole as a hand or fluted chuck-
ing reamer and is not used when a smooth hole is required.
See 295. It is obtainable in standard sizes and also with
taper shank to fit drill sockets.
FIG. 196. REAMING FLANGE CASTING BY POWER IN LATHE.
297. Broach reamers for small taper pins. Collars, A, and
similar work are often fastened to shafts by drilling, ream-
ing, 5, and pinning, C, Fig. 197,
REAMING.
145
Broach reamers may be supplied with a handle, as at E,
and used by hand to enlarge holes and to remove burrs. They
are obtainable in tapers of \" and TV per foot, and in sizes
from No. 1 to No. 70 (drill and wire gage sizes). Taper pin
fluted reamers and taper pins having a taper of J" per foot are
used for pinning or doweling, and are obtainable in sizes from
" to IJ". Each reamer overlaps the next smaller size.
SECTION
OF REAMER
D
FIG. 197. REAMING TAPER PIN HOLES WITH BROACH REAMER IN
SPEED LATHE.
Attention. To avoid breaking taper reamers, feed slowly,
oil freely, and withdraw frequently to remove chips.
CHAPTER XI.
MANDRELS OR ARBORS. MANDREL MAKING. TURNING AND
FINISHING FLANGES. TURNING AND FINISHING
PULLEYS. POLISHING LATHE WORK.
MANDRELS OR ARBORS.
298. A mandrel, often called an arbor, is pressed, driven, or
threaded into work to provide centers so that it may be
machined.
An arbor is a shaft used to carry a cutting tool, as a mill-
ing machine arbor, a saw arbor, etc.
Three classes of mandrels are used: solid, expanding, and
built-up. See Nut Mandrel, 256.
299. Standard solid mandrel, AB, Fig. 198, is made of
LARGE END
A
SMALL END
FIG. 198. MANDREL OR ARBOR.
tool steel, hardened and ground. See Table of Mandrels,
665. The size is stamped at large end, as at C. A portion
MANDREL
FIG. 199. SECTION OF MANDREL END.
of each end is reduced and flattened to receive the driving dog.
The ends are recessed as at D, Fig. 199, around the counter-
sinks to protect them from injury.
Important. For accurate work, mandrels should be tested
to see if they run true. See 635, 636.
146
MANDRELS.
147
300. Expanding mandrel. Fig. 200 consists of shaft A
having uniformly tapered slots as at B. Sleeve C guides ta-
pered jaws D (see D') while they are being adjusted to the work
by the sliding of the shaft A.
FIG. 200. EXPANDING MANDREL.
301. Bridges in hollow castings A, Fig. 201, are often cast
across the ends as at B, to provide for center holes.
FIG. 201. BRIDGE IN HOLLOW CASTING FOR CENTER HOLE.
302. Revolving dead center for pipe turning. - To square
or turn small pipe, mount upon ordinary lathe centers. For
large pipe or cored work, a special large dead center is needed,
FIG. 202. REVOLVING DEAD CENTER FOR PIPE TURNING.
preferably one that will revolve as at A } Fig. 202, in which
cone B revolves upon shank C. A solid live center or chuck
may be used at other end.
303. Built-up and special mandrels. To face the ends of
small engine cylinders or similar work, a built-up mandrel is used.
See Advanced Machine Work. To face the ends of a piece of pipe
148
PRINCIPLES OF MACHINE WORK.
or cored work, make a mandrel by drilling and tapping three
or four holes around each end of a stiff shaft and inserting
adjusting screws to bear against the inside of work.
For large shells, tubes, etc., castings called " spiders " are
used consisting of arms projecting from a hub, each arm
supplied with a screw to bear against the work, and the hub
supplied with set screws to fasten spider to mandrel.
A special mandrel may be made of any suitable piece of
stock by centering, turning, and filing to fit the hole.
304. Soft hammers for driving mandrels into work are made
of lead or rawhide. A steel hammer should never be used
without protecting work with a block of wood, copper, or lead.
Attention. Molds are obtainable for molding lead hammers.
305. Mandrel or arbor block. Fig. 203 shows the relative
position of block A, mandrel B, work C, and soft hammer D
when driving a mandrel into the work.
MANDREL
OR
ARBOR
PRESS
A
FIG. 203. DRIVING MANDREL
INTO FLANGE.
FIG. 204. FORCING MANDREL
INTO FLANGE WITH MANDREL
PRESS.
306. Mandrel or arbor press, A, Fig. 204, is used to press man-
drel B into workC by forcing spindle D against the mandrel with
handle E. Pointer F may be set to adjust mandrel for dupli-
MANDREL MAKING.
149
cate pieces. The press may be bolted to a lathe as at G, or
mounted on a stand. It may be used also for forcing fits.
307. Center mandrel for bottom holes. Mandrels made to
fit the hole in the live spindle of a lathe are used to hold caps,
oil cups, bottom or blind nuts and similar work that must be
machined. The projecting end is turned either to a slight
taper to receive work with a plain hole, or threaded to hold
threaded pieces.
308. Studs for driving large work instead of dog. Work
of large diameter, as a large pulley, may be driven by its arms
with one or more studs fastened to the face plate of lathe.
Attention. Oil mandrel before pressing or driving it into
work. Take light cuts when using small mandrels to avoid
springing of mandrel and chattering, producing irregular tool
marks.
MANDREL MAKING.
309. To make a standard lathe mandrel, Fig. 205, involves
practice in squaring, turning, milling, hardening, tempering,
and cylindrical grinding.
If not equipped with cylindrical- grinding machine, harden
and temper ends only, turn body slightly taper and file to fit
standard hole.
ANGLE OF RECESS JJ20**>
FIG.' 205. SCHEDULE DRAWING.
310. To prepare T y standard mandrel blank for hardening,
tempering, and grinding, Fig. 205.
150
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Material, annealed carbon steel T V large ; weight, 8 oz .
True live center. Set dead center in approximate alinement.
Machine dry or use lard oil.
Use high-speed steel cutting tools. See Exception, p. 59.
Time, 1 h. 45 min. to prepare blank.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Center to ^". (1), (2). See
Centering machine.
z" drill, or combina-
(A), Fig. 205.
Drill 1000 R. P.M.,
tion drill and coun-
countersink 400
tersink, 60. Lard
R.P.M.
oil.
Rough square to 5" + ^*,
Engine lathe 12" to
Dog, side tool, or
(3), (4).
16", 2d or 3d speed,
holder and cutter,
or 35 F.P.M. Hand
30 rake, calipers,
feed.
rule.
Recenter to &", (1), ().
Speed lathe, 2d or 3d
Drill, countersink,
speed.
lard oil.
Finish square to length, (3),
Engine lathe, 3d or
Dog, side tool or
(4).
4th speed, or 50
holder and cutter,
F.P.M.
30 rake, calipers,
rule.
Roxigh turn reduced portions
2d or 3d speed, or 30
Copper under set
to M" + &" (5), (6),
F. P. M. Medium
screw of dog, dia-
one or two cuts. Do not
power feed 80 to
mond-point tool ,
square shoulders but leave
1".
or holder and cut-
fillets as shown to avoid
ter, 30 rake, cali-
cracking in hardening.
pers, rule.
Recess countersinks to dimen-
3d or 4th speed, or 50
Side tool or special
sions ^". Angle 20, (7),
F.P.M.
countersink. See
(8). See (B), Fig. 205.
Fig. 23. Lard oil.
Recenter to &*, (1), (3).
Speed lathe, 2d or 3d
Drill, countersink.
speed.
Finish turn reduced portions,
Engine lathe, 3d or
Copper under set
(5), (6), one cut.
4th speed, or 50
screw of dog, dia-
F.P.M. Fine power
mond-point tool, or
feed 140 to 1".
holder and cutter,
30 rake, calipers,
rule.
Smooth turn body to .580*.
2d or 3d speed, or 30
Micrometer, copper
Turn half of length and re-
F. P. M. Fine
under set screw of
verse (9), one or two cuts.
power feed 140
dog, diamond-point
to 1".
tool, or holder and
cutter, 30 rake,
-
calipers, rule.
MANDREL MAKING.
151
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Concluded.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Round corners, (1O), (11).
File reduced portions.
Polish reduced portion, also
ends and recesses except
countersinks, (5), (6). See
319-322.
Mill or file and polish flats,
(12), (13).
Stamp size ^", (14), or mill or
file flat and stamp size at
(C).
Stamp name or initials (15).
Harden (test with file), leave
ends black, or polish and
temper ends to dark straw.
See Elements of Machine
Work.
To lap center holes, see Atten-
tion below.
To grind, see 422.
Speed lathe, 3d or 4th
speed, or 200 F.P.M.
3d or 4th speed, or
175 F.P.W.
Speed lathe, highest
speed.
Milling machine, 3d
speed, medium pow-
er feed.
Vise.
Gas furnace or forge,
speed lathe. Oil,
tempering furnace.
Graver.
8" or 10" mill bastard
file.
Lard oil, 90 and 120
emery cloth, pol-
ishing stick.
To mill, use milling
machine vise, par-
allel piece, 1" end
mill, rule, lead ham-
mer, oil. To file,
use 8" or 10" hand
smooth and 5" half-
round, 2d cut files.
To polish, use oil,
90 and 120 emery
cloth.
3$" steel figures, \"
chisel, hammer,
copper jaws.
Steel name stamp.
Tongs, water, brine,
or sperm oil, oily
waste, dead smooth
file, red-hot iron
rings or oil temper.
Attention. The hand tools may be carbon steel.
See Table of Mandrels, 665.
Note. For very accurate work, center holes in mandrels are
lapped smooth and true before grinding, but this process is often
omitted on mandrels for general work. To make a lap, hold a piece of
152
PRINCIPLES OF MACHINE WORK.
copper rod in chuck of speed lathe and turn with graver or planisher
to 60. Test with center gage. Charge lap with 120-grain emery and
oil. Mount mandrel on dead center and on lap. Run lathe at
highest speed, revolve mandrel slowly backward, and relieve dead
center occasionally.
For further information on Lapping, see Advanced Machine Work.
TURNING AND FINISHING FLANGES.
311. To clamp carriage to face large work in engine lathe.
Feed tool to its cut by hand, then clamp carriage with bind-
ing screw and use power cross feed.
In the absence of power cross feed and clamp, throw feed
belt off or feed gears out of mesh. Run tool close to work,
tighten long, feed friction knob, revolve feed shaft by hand
until tool takes required cut and then feed tool inward or
outward with hand cross feed.
CAST
IRON
FLANGE
B
MANDREl
C (
ROUGHING CUT
FIG. 206. ROUGH FACING FLANGE.
312. To rough turn face of cast-iron flange, Fig. 206.
Use round-nose tool A for roughing flange B on mandrel C.
Fasten tool in post D, and clamp carriage. Feed in direction
of arrow E to outer edge of fillet.
TURNING AND FINISHING FLANGES.
153
313. To finish and scrape face of cast-iron flange, Fig. 207,
to prepare for polishing. Take light finishing cuts with
FIG. 207. FINISH FACING FLANGE.
facing tool A ground to 60, as at C and D, at medium high
speed. Grind and oilstone top face of tool. Set it to drag a
little as at E and feed in direction of arrow F. Use scraper
EXPANDING
MANDREL
c\
CAST
IRON
FLANGE
DCC
FIG. 208. SCRAPING RADIAL FACE OF FLANGE.
A, Fig. 208, with cutting edge C D ground straight, or slightly
convex, at medium speed. Hold scraper on rest E and move
in direction of F with point dragging a little as at G. A piece
of leather placed under scraper will often prevent chattering.
154
PRINCIPLES OF MACHINE WORK.
314. To scrape inside rounds or fillets to the desired curva-
ture. First shape with a round-nose lathe tool. Then use a
round-nose hand tool, A, Fig.
209, to prepare filleted corner of
flange B for polishing. C and
D show point and clearance of
tool. To avoid chattering, cur-
vature of end E should be
greater than that of fillet for
clearance and the tool should be
held firmly on rest. A round
or half-round file is sometimes
used to smooth a fillet.
Attention. Cylindrical sur-
faces are more easily prepared
for polishing than radial and
curved surfaces. On small work a light finishing cut is taken
with a fine feed, and on very large work a light finishing cut is
FIG. 209. SCRAPING FILLET IN
FLANGE.
FIG. 210. SCHEDULE DRAWING OF MAKING A CAST-IRON FLANGE.
taken with a broad-nose tool and a coarse feed, and the surfaces
filed to erase the tool marks.
315. To make a cast-iron flange finished all over. Fig. 210.
TURNING AND FINISHING FLANGES.
155
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Material, iron casting \" large; weight 4 Ib. 4 oz.
True live center. Set dead center in approximate alinement.
Use high-speed steel cutting tools. See Exception, p. 59.
Time, 1 h. 20 min.
OPERATIONS.
MACHINES, FEEDS,
SPEEDS
TOOLS.
Snag casting. Mount in chuck
Engine lathe, 12" to
File, independent
and adjust until hub runs
16". 2d or 3d speed,
chuck, chalk, drill
true. Drill and rough ream
or!15R.P.M.Hand
rest, flat drill. f",
hole, (1), (2).
feed.
flat reamer, T 9 oY'.
Finish ream hole by starting
Reaming stand or
1* standard hand
reamer in lathe, pull belt by
vise. See 305,
reamer, reamer
hand, complete at reaming
306.
wrench.
stand or vise, (3). See
292, 289.
Oil mandrel and press into
Mandrel press. En-
V mandrel, holder
hole in direction hole was
gine lathe, 4th
and cutter or dia-
reamed. See 305, 306.
speed. Back gears
mond-point tool,
Mount on centers and
in, or 35 F. P. M.
15 rake, calipers,
rough turn ^j" oversize,
Medium power feed
rule.
(4), (5).
80 to 1".
Rough face, (6) ; feed inward;
4th speed. Back gears
Round-nose tool or
rough fillet, (7) ; rough face,
in, or 35 F.P.M.
holder and cutter,
(8); reverse work on cen-
Hand or medium
15 rake. 2 rules,
ters, then rough (9).
power feed.
or inside calipers
and rule, to meas-
ure length of hub.
Finish turn, (10), (11).
2d or 3d speed (back
Holder and cutter or
gears out) or 125
diamond-point tool,
F.P.M. Fine power
15 rake, calipers,
feed 140 to 1".
rule.
File, (10), (11).
3d speed, or 175
8" or 10" mill bastard
F.P.M.
file, file card.
Finish face with cuts .002" to
2d or 3d speed, or
Facing tool, flat
.003" deep and scrape, (12).
125 F.P.M.
scraper.
Finish face and scrape, (13).
2d or 3d speed, or 125
Round - nose tool,
F.P.M.
round-nose scraper.
Finish face and scrape, (14).
2d or 3d speed, or 125
Facing tool, flat
F.P.M.
scraper.
Finish (do not scrape or pol-
1st or 2d speed, or 60
Facing tool, calipers,
ish), (15).
F.P.M.
rule.
Cut recess %$" deep. Set side
1st or 2d speed, or 50
Side tool, calipers,
tool at 45, feed outward,
F.P.M. Hand or
rule.
two or three cuts, (16).
medium power feed
80 to 1".
156
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Concluded.
OPERATIONS.
MACHINES, FEEDS,
SPEEDS.
TOOLS.
Polish, (10), (11), (13), (13),
(14). See 319-321.
Jig drill, and ream holes, (17).
Cut keyway central, (18).
Stamp name or initials in
recess, as E.R.N.
Speed lathe, highest
speed.
2-spindle drilling ma-
chine. Drill 600
R. P. M. Power
reamer, 400R.P.M.
Hand feed.
Planer and vise or key
seating machine.
Polishing stick, 60,
90, 120, emery cloth,
oil.
Box jig, ff drill,
power reamer.
Keyway tool holder
and cutter, " wide.
Steel name stamp,
hammer.
Attention. Finishing cuts 10 and 15 may be omitted until flange is
keyed to its shaft. The hole may be chucked with a f f " twist drill
or, if cored, with a three or four-groove drill, and hand reamed
(1), (3). The hand tools may be carbon steel.
Note. Bushings, collars and step pulleys or any other work
mounted on a mandrel, with one, two, or more diameters, are machined
in the same general manner as the flange in Fig. 210.
TURNING AND FINISHING PULLEYS.
316. The taper or crowning on the face of pulleys, ranges
from \" per foot for large pulleys to J" per foot for small pulleys.
Tapered-face pulleys are made commercially in a pulley lathe
with two cutting tools operating at same time, one on the
front, the other on the back of machine, or in turret lathes
with special tools.
The face of the pulley is often crowned in a forming lathe
or ground in special grinding machines from the rough casting.
The hubs of pulleys used in combination, as tight and loose
pulley mechanism, are squared.
Pulley A, Fig. 211, is turned in an engine lathe. The rim
is faced as at B. The face is tapered as at C. The rim may
TURNING AND FINISHING PULLEYS.
157
be chamfered as at D, or rounded with a right-and-left form-
ing tool as at E, E' '.
The set-over^of footstock for ordinary tapers is forward, as at
A, Fig. 212, and for pulleys it is backward as at B.
TAPER CHAMFER
FACE RIM
FIG. 211 PULLEY TURNING IN ENGINE
LATHE.
B
' IDEAD CENTER SET BACK
FOR TAPERING PULLEYS
DEAD CENTER SET FORWARD
FOR ORDINARY TAPERS
FlG. 212.
158
PRINCIPLES OF MACHINE WORK.
317. To make a pulley 5" in diameter.
STOCK PULLEY CASTING >0 MEANS FINISH TAPER -5- IN. TO 1 FT.
FIG. 213. SCHEDULE DRAWING.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Material, pulley casting. Surfaces to be finished T y large ; weight,
2 Ib. 5 oz.
True live center. Set dead center in approximate alinement.
Use high-speed steel cutting tools. See Exception, p. 59.
Time, to chuck, 25 min.
Time, to turn and square, 1 h.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Snag casting. Fount in chuck
Engine lathe, 12" to
File, chuck, chalk,
and adjust until edge and
16". 3d speed, or
lathe centering tool,
inside of rim run true.
400 R.P.M. Hand
||" twist drill, dog,
Drill and rough ream hole,
feed.
chucking reamer,
(1), (2).
.005", small.
Finish ream hole by starting
R earning stand or vise .
^5" standard hand
reamer in lathe, pulling belt
See 305, 306.
reamer, reamer
bv hand, completing at vise,
wrench.
289, (3).
Oil mandrel and" press into
Mandrel press. En-
Dog, standard man-
hole. See 305, 306. Mount
gine lathe, 3d or 4th
drel, holder and cut-
on centers and rough turn
speed, back gears
ter or diamond-
to 5", (4), one or two cuts.
in, or 35 F. P. M.
point tool, 15 rake,
Medium power feed
calipers, rule.
80 to 1".
TURNING AND FINISHING PULLEYS.
159
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Concluded.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Rough square edges of rim to
lf' + -h", (5), (6). Take
3d or 4th speed, back
gears in, or 50
Holder and cutter or
round-nose tool, cal-
equal cuts from each side.
F. P. M. Hand or
ipers, rule.
medium power feed
80 to V.
Regrind tool, finish square
edges to width, (7), (8).
Take equal cuts each side.
Coat a small portion of face
Copper sulphate or
with copper sulphate or chalk
chalk, divider- cali-
and make line midway be-
pers or dividers,
tween edges, (9).
rule.
Set footstock back to turn-
3d or 4th speed, back
Holder and cutter or
taper of \" per foot (&"
gears in, or 50
diamond-point tool.
for 5 between centers) and
F.P.M. Fine power
set tool to touch line (9),
feed 140 to 1".
and feed toward headstock.
Reverse pulley, reset tool
and repeat, (10), (11).
Chamfer at 45 inside corners
2d speed, back gears
Side tool, 15 rake.
of rim, or round with form-
in, or 25 F.P.M.,
ing tool, (13), (13).
hand feed.
Time, to file and polish, 20
min.
File face, (14), (15). Scrape
2d speed, or 175
8" or 10" mill bastard
edges, (16), (17).
F.P.M.
file, graver.
Polish face and edges, (18),
Speed lathe, highest
60, 90, 120 emery
(19), (20), (31), See 319,
speed.
cloth, polishing
321.
stick, oil.
Drill and tap hole for set
Vertical drilling ma-
fa" extension drill,
screw, insert \" X i" round-
chine, 3d speed,
X 20 U. S. S.,
point set screw, (22).
hand feed. Tilting
pulley tap, wrench,
vise or fixture.
lard oil.
Stsmo nirri<3 or inititxl on Gnd
Steel name stamp,
of hub.
hammer.
Paint unfinished parts.
Special black paint.
Attention. Power chucking reamer may be omitted, as a good
hole may be obtained with a drill and hand reamer.
When possible, place arms of pulley opposite chuck jaws. The hand
tools may be carbon steel.
Warning. Do not rub greasy fingers on cast iron before or during
filing or scraping as the file will slip, glaze and scratch a greasy cast
iron surface.
160 PRINCIPLES OF MACHINE WORK.
318. To locate set screws, Fig. 213. If the boss is central
as at A, drill body hole D in rim through which to tap hole A,
and use a cup or round-pointed set screw. Where the boss is
flat as at B and placed at one side, drill a body hole through
rim E. If a body hole through rim is objectionable, hold
pulley in a tilting vise or fixture and drill and tap hole at
angle, as at C.
In large pulleys use two set screws or key.
POLISHING LATHE WORK.
319. Use a speed lathe for polishing but never an engine
lathe when it can be avoided, as the gritty spatterings injure its
bearings. Make exception only to work machined in a chuck
of an engine lathe which must be polished before it is removed.
An effective polishing speed for emery, alundum, or car-
borundum cloth is between 5000 and 6000 F.P.M.; that is, a
surface speed of about a mile a minute (5280 feet).
It is not always possible to obtain this high speed, as speed
lathes are usually belted for a great variety of work, as drilling,
hand turning, etc., and their highest speed will not give the
maximum polishing speed for small work.
On work that is unbalanced, it is not desirable, and often
dangerous, to polish at the maximum speed, as it will shake
the lathe and the work may fly off the centers. It is best to
use as high a speed as the nature of the work will permit, since
the polishing can then be done with less labor and with less
tendency to destroy the truth of the- work.
320. Order of applying different numbers of emery cloth.
If the work is carefully finished,, limited application of 60
and 90 will produce an effective polish; and if the work is
finished extra fine, 90 will be sufficient. If a more brilliant
polish is desired, use 120 and flour. For large work not given
a fine finish it may be necessary to begin with 46 or 54.
Apply 60 emery first with hard pressure until all tool
marks and scratches are removed and the pore.s in the metal
have nearly disappeared. Then apply 90 emery with lighter
pressure until all evidence of 60 is removed. If on applying
POLISHING LATHE WORK.
161
90, tool marks, deep scratches, or large pores appear, return
at once to 60 emery. Follow this method in applying succes-
sive grades of emery.
Use lard oil on the emery cloth or work, distributing it with
the fingers.
321. To polish flange, Fig. 214. Oil speed lathe and shift
belt to highest speed. Press mandrel in flange A, which has
been carefully finished by turning, filing, and scraping. Fasten
dog on mandrel. Mount and adjust on centers. Wrap a
strip of No. 60 emery cloth B around end of wedge-shaped soft-
pine stick C. Drop a little oil on emery cloth or flange and
distribute with fingers. Start lathe and pivot stick on rest D
which should be clamped from 2" to 2J" from the work.
Keep emery moving back and forth slowly along the work
so that the marks will cross and recross each other, to avoid
cutting grooves. Grades 60 and 90 will produce a good pol-
ish on a flange.
To polish radial face of flange, clamp rest D parallel to face
and from 2" to 2J" distant. Apply emery cloth in same order
FIG. 214. POLISHING A FLANGE IN SPEED LATHE.
as on hub. Keep emery moving slowly, advance and recede in
short strokes toward the center to avoid cutting grooves, then
recede in the same order. To polish the fillet, move emery
cloth back and forth in short strokes following the curve.
162
PRINCIPLES OF MACHINE WORK.
322. To polish a shaft with wood polishing clamp, AA'
(Fig. 215), hinged by leather at end. Oil speed lathe and shift
belt to highest speed. Place dog on shaft with copper under
set screw, and mount shaft on centers. Drop a little oil on
emery cloth or shaft and distribute with the fingers. Wrap
FIG. 215. POLISHING A SHAFT IN SPEED LATHE.
emery cloth B around shaft C in one fold only, and hold end
as at D, to prevent it from winding around shaft. Apply
pressure with the left hand, and with the right move clamp
back and forth in short strokes along shaft so that the marks
will cross and recross each other. Move clamp continuously
when in contact with revolving work, otherwise emery will cut
grooves. Grades 60 and 90 will produce a good polish on a
shaft.
323. To polish brass and copper, use a finer emery cloth than
for steel or iron, as the material is softer. Start with a No. 90,
continue with No. 120 flour, and crocus cloth. If a more
brilliant luster is desired, the work may be buffed.
For Polishing and Buffing with Wheels and Belts, and
Lacquering, see Advanced Machine Work.
POLISHING LATHE WORK. 163
Attention. Use oil sparingly to avoid excessive spatter-
ing. Do not allow the emery cloth to slip off the edge of
work as it will round the corners. Adjust mandrel, or work
freely on centers, and occasionally loosen and oil dead center,
as the heat generated will expand the work or mandrel and
burn off the dead center.
To lay lines uniformly after work is polished, moisten a
piece of worn emery cloth of fine grade with oil (or oil the
work, distributing it with the fingers) and move the emery
cloth slowly along the work.
Important. If holes are to be drilled in a surface that is to
be polished, polish the surface first and drill the holes afterward.
CHAPTER XII.
HAND TURNING. MAKING MACHINE HANDLES. DRILLING,
TAPPING, AND HAND THREADING IN SPEED LATHE.
SPRING WINDING.
HAND TURNING.
324. Hand turning tools such as the graver, round-nose tool,
etc., are forged from y to f " square, hexagonal, and round,
carbon steel, hardened and tempered the same as engine lathe
tools (see Elements of Machine Work), and generally used in a
speed lathe. See 23.
325. Cutting speeds and angles for hand tools. The
cutting speed for steel, wrought iron and cast iron is greater
than that for engine lathe cutting tools, from 150 F.P.M. to
225 F.P.M. , as the cuts are lighter and not so continuous.
See Hand Tools for Brass Finishing, 341. The cutting
angle and clearance are obtained both by grinding and by
the manner in which tool is presented to work, the latter de-
pending somewhat on the height of Tee rest.
326. Methods of holding work in speed lathe depend on the
shape of the work: first, by centering and mounting work
upon the centers; second, by holding in chuck; third, by
holding one end in chuck and centering projecting end, using
dead center to steady work. Small work of curved outline,
except chuck work, can be more rapidly finished in a speed
lathe.
Important. All metals are hand turned without a lubricant.
327. The Tee rest is used to support the tool, and should be
placed from J" to I" from work, depending on kind of tool used.
With a few exceptions, the cutting edge of tool should be the
same height as the lathe centers.
328. The graver, Fig. 216, except for inside rounds, is the
most useful hand turning tool for both roughing and finishing.
164
HAND TURNING.
165
The cutting edges are A B and A'B. They are obtained by
grinding B'C to an angle of about 60 end clearance.
Attention. On account of the keen cutting angle of the
graver, care should be taken when using it on brass. See
341.
FIG. 216. GRAVER OR DIAMOND-POINT HAND TOOL.
329. To rough turn cylindrical surfaces with graver, Fig. 217.
Work D is mounted on centers. Graver F is held on the
rest horizontally, to turn cast iron. For steel, wrought iron,
or copper, the handle is lowered to give it rake. To bring tool
FIG. 217. ROUGH TURNING WITH GRAVER IN SPEED LATHE.
to its cut, elevate handle. To rough turn work, pivot graver
upon rest, move point from right to left parallel to work.
Test work frequently with calipers. See Slide Rest, 352.
330. To finish turn cylindrical work with graver, Fig. 218.
Press graver G hard on rest H with edge nearly parallel to
166
PRINCIPLES OF MACHINE WORK.
work so that it will drag, carry finishing cut toward head-
stock, or vice versa.
FIG. 218. FINISH TURNING WITH GRAVER.
331. Step method of squaring with graver, Fig. 219. A
number of short cuts are taken on work J with graver K until
the center is reached. In Fig. 220 the graver is turned over
and the cut started at center and carried outward by depress-
ing handle to finish square.
FIG. 219. ROUGH SQUARING
WITH GRAVER BY STEP METHOD.
FIG. 220. FINISH SQUARING
WITH GRAVER.
332. The round-nose hand tool, Fig. 221, is used for inside
rounds and fillets, and can be used for rough turning cylin-
FIG. 221. ROUND-NOSE HAND TOOL.
drical work. When employed on steel or wrought iron, it will
cut better if top face is ground hollow, as at A, to give it rake.
It is used in a manner similar to the graver.
MAKING MACHINE HANDLES.
167
MAKING MACHINE HANDLES.
333. Single handles are made as outlined in Figs. 222, 223,
and 224. When manufactured in quantities, they are drop-
forged to shape or made from bar stock with a forming tool in
SPEED
LATHE
.Fia. 222. CURVED TURNING WITH HAND TOOLS. TESTING
WITH TEMPLET.
FIG. 223. FINISHING MACHINE HANDLE WITH HAND TOOLS.
OVERHEAD TURNING.
a turret lathe. By either of the latter methods, they require
but a small amount of hand finishing.
334. Templets of sheet brass or steel, E, Fig. 222, are used
for duplicate work, serving as a pattern or guide to uniform
production.
168
PRINCIPLES OF MACHINE WORK.
They are lined out from specifications on the drawing, and
are rough cut by chipping, or with shears, and finished by
filing. Templets are used as guides when rough turning or
planing, and for careful tests when finishing.
335. To make a machine handle, Fig. 224.
FIG. 224. SCHEDULE DRAWING OF MACHINE HANDLE.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
ROUGHING. FINISHING.
Material, machine steel T V' to \" large; weight, 15 oz.
True live center. Set dead center in approximate alinement, see
40.
Lard oil may or may not be used in squaring and turning steel or
wrought iron.
Use carbon-steel cutting tools. See Exception, p. 59.
Time, 2 h. 45 min.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
File ends flat.
Vise.
File.
Center.
Centering machine.
Drill, 1250 R.P.M.
&" drill, 60 counter-
sink, lard oil.
Countersink, 700
R.P.M.
Rough square, (1), (3). See
Step Method of Rough
Squaring, 178.
Engine lathe, 12 to
16*. 2d speed, or 35
F.P.M. Hand feed.
Dog, side tool, 35
rake, calipers, rule.
Recenter.
Speed lathe, 2d or 3d
speed.
MAKING MACHINE HANDLES.
169
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Continued.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Finish square, (3), (4).
Rough turn ^j" large, (5).
One cut. Turn one-half of
length, reverse and turn the
other half.
Rough turn -fa" large, (6).
One cut. Turn to (6'),
about !" from end.
Hold in vise and mark lines 1"
from each end at (A) and
(B).
Rough turn $^" large, (7).
Two or three cuts.
Rough turn convex parts (8),
(9), and concave part (1O),
several cuts. Operate both
feeds in combination, by
hand, and test with templet,
as at E, Fig. 222.
Rough turn with graver, (11),
(12). See A and A', Fig.
222. Test often with tem-
plet.
Rough turn, (13). See B,
Fig. 222. Test with templet
and calipers at diameters
i" and I".
Finish turn, (14), (15). See
C, Fig. 223.
Finish turn, (16). See D,
Fig. 223.
Finish turn, (17).
Engine lathe, 3d
speed, or 50 F.P.M.
Hand feed.
2d speed, or 35 F.P.M.
Medium power feed
80 to 1".
Vise.
3d speed, or 35 F.P.M.
Medium power feed
80 to \".
3d speed, or 50 F.P.M.
Speed lathe, 8 to 12",
2d speed, or 150 or
F.P.M.
3d speed,
F.P.M.
or 225
Engine lathe, 12 to
16", 3d speed, or
50 F.P.M. Fine
power feed 140
to 1".
Diamond-point tool ,
or holder and cut-
ter, 35 rake, cali-
pers, rule.
Copper sulphate,
scriber, rule.
Calipers, rule.
Copper under set
screw of dog, dia-
mond-point tool, or
holder and cutter,
35 rake, templet.
Graver.
Round - nose hand
tool, templet, cal-
ipers, rule.
Graver, templet, cali-
pers, rule.
Round-hand tool,
templet, calipers,
rule.
Diamond-point tool,
or holder and cut--
ter, 35 rake, cali-
pers, rule.
170
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF MACHINES, OPERATIONS AND TOOLS.
Concluded.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Rough and finish turn, (18).
Copy the reverse curve (the
ogee) as accurately as can
be determined by the eye,
or make a templet from
specifications or curve on
drawing. See 334.
Speed lathe, 3d speed,
or 225 F.P.M.
Graver, round-nose
hand tool.
File, (14) and (15).
File, (16) and (18)
3d speed, or 175
F.P.M.
8" to 10" mill bastard
file.
5" to 8* half-round
smooth file.
Polish, (14), (15), (16), (18).
Speed lathe, highest
speed.
60, 90, 120 and flour
emery cloth and
stick, oil.
Stamp name or initials, (19).
Vise.
Steel name stamp,
hammer, copper
jaws.
Attention. Part 17 is usually fitted to a hand wheel, or other
machine part, by a forcing or threaded fit; if so, operation 17 is omitted
to allow the desired fit to be made later.
Note. The machine handle may be finished with graver and round-
nose hand tool used horizontally, as in Fig. 222, or with graver and
round hand tool, by overhead turning, as in Fig. 223.
DRILLING, TAPPING, AND HAND THREADING IN SPEED
LATHE.
Fia. 225. CUTTING A CONICAL CAVITY AXIALLY TRUE WITH GRAVER
TO START TWIST DRILL.
DRILLING, ETC., IN SPEED LATHE.
171
336. To cut a conical cavity axially true with graver,
Fig. 225. Hold nut A in chuck B. Set Tee rest C to bring
edge of graver D at height of center. Hold graver down
hard on Tee rest and at the same time press it into work. If
graver is not held firmly, it will not produce a cavity axially
true. If the work is brass, it is best to use the corner of the
planisher. See Planisher, 344.
337. To chuck with twist drill in speed lathe, Fig. 226.
Make a conical cavity in work E, true to axis of rotation and,
approximately, to the angle and diameter of drill. Fasten
dog G to drill F and place in conical hole, with dog on rest J
and dead center H in end of drill. Grip dog with left hand,
start lathe and feed drill toward headstock with the right
hand.
FIG. 226. CHUCKING WITH TWIST DRILL IN SPEED LATHE.
Attention. Hold drill firmly and do not allow it to draw
off dead center, which may cause drill to break and may spoil
the work.
338. To tap work in speed lathe, Fig. 227. See 534.
Place tap wrench K on tap L and then insert in hole in work
M, held in chuck N. Guide tap by dead center 0, allowing
handle of wrench to bear on rest P.
172
PRINCIPLES OF MACHINE WORK.
Rotate work by pulling belt Q, or rotate cone R, and feed
footstock spindle to follow up tap with dead center.
Attention. Carefully follow up tap with dead center, as
the tap will break if it slips off.
Important. As small taps break easily, it is best only to
start tap in the lathe and then finish at vise.
FIG. 227. TAPPING IN A SPEED LATHE.
FIG. 228. THREADING WORK IN SPEED LATHE WITH A DIE BY HAND.
339. To thread work held in chuck with die and stock by
hand, Fig. 228. Chamfer end of work A, held in chuck B, as
DRILLING, ETC., IN SPEED LATHE.
173
at C'j to assist starting die centrally. Remove dead center,
insert table center D, place muzzle side of die E against
work (see E') and handle G on Tee rest H. Feed spindle F
in until D presses against die stock. Rotate lathe by hand,
following up die with D until thread is started. To terminate
thread abruptly reverse die.
Important. Work A must be true to the axis of rotation
(hand or power) otherwise the die will cut a crooked thread. If
the universal chuck is not true, correction may be made by plac-
ing paper between the jaws and the work, see 268 and 266.
340. Hand chasers are used to cut fine threads (20 to 70 P)
on brass tubing, and may be used to finish threads partly cut.
The teeth of chasers are cut by milling or by pressing the
blank against a master or hob tap revolved in a lathe.
Screws, Fig. 229, are threaded as indicated at A, B and
A', B f . Run lathe at medium slow speed. Carefully move
chaser along rest one pitch per revolution of work. After the
thread is started it helps to guide the chaser. Lack of experi-
ence or carelessness may cause the chaser to produce a double
thread or a drunken thread (irregular spiral).
FIG. 229. CHASING OUTSIDE THREADS.
Nuts, Fig. 230, are threaded as indicated at A, B and A', B'.
Attention. To thread successfully with hand chasers
requires intelligent practice. They are not used as much as
174
PRINCIPLES OF MACHINE WORK.
formerly, except on thin tubing, on account of the improve-
ment in taps and dies.
HAND
LATHE
FIG. 230. CHASING INSIDE THREADS.
341. Hand tools for brass finishing. Brass and compo-
sition castings may be hand turned at a speed of 500 F.P.M.
Bronze or gun metal, which is harder than brass, may require
a slower speed. Rolled brass may be turned at a speed nearly
as high as hard wood. See Brass Turning in Engine Lathe,
357.
342. Ripper or rough turning tool, Fig. 231. The top and
side views are shown at A, B, and end view at C and C',
c 1
FIG. 231. RIPPER OR ROUGH TURNING TOOL FOR BRASS.
The ripper is shaped by forging, and sharpened by grinding
and oilstoning. It is a good tool to rough turn brass.
343. Method of using ripper, Fig. 232. Hold tool as
shown at D, F and G. Place Tee rest close to work H, use
DRILLING, ETC., IN SPEED LATHE.
175
FIG. 232. ROUGH TURNING A BRASS CASTING WITH RIPPER.
it as a fulcrum, and move handle from right to left, move tool
along rest and repeat operation. Rough turn work ^/ large,
and finish turn with planisher.
344. Planisher or flat scraper. Fig. 233 (A, B) is used
for finishing brass. The cutting end, C, C", is forged, and
ground and oilstoned on end, sides and edges.
FIG. 233. FINISH TURNING BRASS WITH PLANISHER.
345. Method of using planisher, Fig. 233. Hold similarly
to ripper. Place at angle indicated at D, slide along line E F
from right to left or vice versa. If it chatters, use it at top of
176
PRINCIPLES OF MACHINE WORK.
work and reduce length of cutting edge, as at G, by carrying
cutting edge at slight angle with work, as indicated by line HI.
To finish a spherical surface, hold planisher as at J.
Fig. 234, K, L, M, and N, shows a few of the purposes, both
roughing and finishing, for which a planisher may be used in
its regular or special form.
FIG. 234. ROUGHING AND FINISHING ROLLED BRASS WITH PLANISHERS.
346. Filing brass in the lathe. It is usually unnecessary
to remove tool marks preparatory to polishing by filing as
brass can be scraped smooth with a planisher.
347. Burnishers and burnishing metal. After polishing
and buffing, plated or unplated work may be given a brilliant
luster by using a steel burnisher, shown at A, B, Fig. 235.
FIG. 235. BURNISHING TO PRODUCE HIGH FINISH.
The burnisher is elliptical in cross-section, as at C, is made
glass hard, highly polished, and by skillful application will
impart a mirror-like surface.
DRILLING, ETC., IN SPEED LATHE.
177
Work D is revolved at high speed and the burnisher is
lubricated with vaseline, kerosene, or a solution of borax and
water and is moved along the work slowly with sufficient
pressure to produce the desired luster.
Jewelry, cutlery, silverware, etc., are burnished by hand
with hardened steel tools and also with tools faced with agate
or bloodstone.
348. Hand cutting-off tools are forged and ground as in
Fig. 236, A, B for brass and C, D for steel and wrought iron,
and are used in hand lathe to cut off small stock, as follows:
Press lever E, Fig. 237, with the left knee to release spring
chuck F, and insert rod G through spindle (or rod may be
FOR BRASS
FIG. 236. HAND CUTTING-OFF TOOLS.
held in universal chuck H). Hold tool J on rest K at height
of center, and force inward. To prevent brass cutting-off
tool from binding, cut sideways to increase width of groove.
See Lathe Cutting-off Tools, 197.
FIG. 237. CUTTING OFF SMALL STOCK IN UNIVERSAL HAND LATHE.
349. Improved hand cutting-off tool. After adjusting
the tool on the rod the edge of circular cutter A, Fig. 238,
178
PRINCIPLES OF MACHINE WORK.
is forced into the \" rod by lightly pressing the handles to-
gether. Stop B can be set to cut off equal lengths. Bush-
ings are used in holder C for smaller rods.
FIG. 238. IMPROVED HAND CUTTING-OFF TOOL.
350. Inside hand turning or boring. Work A, Fig. 239, is
held in chuck B. Tee rest C is placed close to work and
INSIDE HAND TURNING TOOL
FIG. 239. HAND BORING AND INSIDE TURNING.
adjusted to bring top of tool D to center of work. Tool D is
then fed inward parallel to axis of work. Point F is ground
with some clearance, as at G. For steel or wrought iron, it
is given rake, as at H.
351. Hand tools from old files. In an emergency, hand
tools of different shapes can be made from old files by first
SPRING WINDING.
179
grinding off the teeth, then grinding or forging to desired
shape.
352. A slide rest, Fig. 240, is a very convenient attach-
ment for a speed lathe for squaring and turning work either
mounted on centers or held in a chuck.
FIG. 240. TURNING IN SPEED LATHE WITH SLIDE REST.
SCHEDULE OF PARTS.
A Base fastened to tee rest
slide.
B Long slide, pivoted on A.
C Cross slide.
D Zero line, for taper turning.
E Handle, long. feed.
F Handle, cross feed.
G Tool-post.
H Cutting tool.
/ Concave and curve wash-
ers for raising and lowering point
of tool.
SPRING WINDING.
353. Coil springs, both extension, Fig. 241, and com-
pression, Fig. 242, made of wire &" and less in diameter, are
wound in a speed lathe; larger sizes are best wound in an
engine lathe with back gears in. For sizes of wire see 667-
668, 669.
FIG. 241. EXTENSION SPRING. FIG. 242. COMPRESSION SPRJNQ.
180
PRINCIPLES OF MACHINE WORK.
354. Spring winder, A, Fig. 243, for winding compression
or extension springs. To wind compression spring B on
mandrel C, rotate web on spacing wheel D into position,
equal in thickness to space between coils. Pass wire E
through lug F, between friction washers through stud G and
through hole in mandrel to fasten. Press spacing wheel
against mandrel and adjust nut H to give desired tension.
Rotate lathe by hand or power, and wind spring. To make
each end flat, wind first and last coils straight.
FIG. 243. WINDING A COMPRESSION SPRING.
Extension springs are wound in the same manner, except
that the thickest web of the spacing wheel is pressed against
the spring after one turn to keep it closed.
Springs when released by cutting off the wire at both ends,
expand some by uncoiling. If the spring is brass, this may be
prevented, to some extent, by blows of a lead hammer applied
over the whole circumference; but if the spring is made of
piano wire, a smaller mandrel should be used to allow for the
expansion. Large steel springs are prevented from expand-
ing by heating red hot before releasing, and hardening and
tempering afterwards.
SPRING WINDING 181
This spring winder may also be used to wind springs by
hand around a mandrel held in a vise. Machines, both hand
and automatic, are obtainable for winding springs.
335. To gear a lathe to wind coil springs. Arrange as for
screw cutting. For a compression spring, the pitch should
equal the space desired between the coils plus diameter of wire,
and for an extension spring the pitch should equal diameter
of wire. Mount mandrel on centers with dog or hold end in
chuck. Pass wire between two blocks in tool-post to give
desired tension, fasten end of wire, start lathe and wind
spring.
356. To wind a compression spring with a wire hook. Place
hook between the coils and have assistant at the back of the
lathe hold end or allow it to hang between the ways and the
carriage. Feed carriage along slowly by hand with a piece
of steel in the tool-post pressing against the spring.
Warning. Be careful in releasing a spring from its wind-
ing arbor by using up all the wire or by cutting off, as it usually
uncoils a little, suddenly, and with a force that may injure
the hands.
CHAPTER XIII.
BRASS FINISHING. MACHINING BRONZE, COPPER, ETC.
NURLING. CURVE TURNING AND FORMING.
STEADY AND FOLLOWER RESTS.
BRASS FINISHING.
357. To turn brass in the engine lathe. Brass, also known
as composition, ranging in hardness from soft yellow to hard
brass or bronze, is generally turned with tools having little or
no rake. High speed and quick feeds are used and the tools
must be kept sharp by frequent grinding to obtain the best
results. See To Machine Bronze, 362. For Cutting Speed,
see 98.
BRASS TURNING
LARGE WORK
[ I BRASS TURNING
SMALL WORK
CL H
ROUND NOSE TOOL
FOR BRASS
SIDE VIEW
FACING OR FRONT TOOL
FOR BRASS
FIG. 244. BRASS TURNING WITH FIG. 245. BRASS TURNING WITH
ROUND-NOSE TOOL. FRONT TOGL.
358. The round-nose tool, as at A and B, Fig. 244, is gener-
ally used for large brass work. It may be used to turn the
182
BRASS FINISHING.
183
diameter as at C, the shoulder, as at D, and the round corner
or fillet as at E, without change of position in the tool post.
359. Use front tool, Fig. 245, with point A, B ground at
angle from 50 to 60 for squaring, turning, or facing, without
change, as at C, Z), and E. If the work is rigid, cut inward
or outward; if slender, cut inward only. This tool may be
ground to fit thread gage, and used as a threading tool for
United States Standard or Sharp V threads.
Attention. As bronze and brass will stretch, it is neces-
sary, when fitting a steel screw to a bronze or brass nut, to
force the screw in hard at first to avoid a loose fit.
Reamed and drilled holes in brass or bronze are usually
smaller than holes made with the same tools in cast iron on
account of the resilient and adhesive quality of these
materials.
Taps, dies, reamers, and files that are used on steel or iron
may be used on brass, but it is best to have separate tools,
for such tools never work as well on brass after they are used
on steel or iron.
Brass in general is machined dry, but to thread rolled brass,
as rod and tubing, with a die, it is usually necessary to use
lard oil to prevent the chips from clinging to the threads of the
die and stripping the threads on the work.
360. To make brass binding post, Fig. 246.
FIG. 246. SCHEDULE DRAWING OF A BINDING POST.
184
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
ROUGHING. FINISHING.
Material, composition or brass castings ^" large; weight, 10 oz.
True live center. Set dead center in approximate alinement.
Use carbon-steel cutting tools. See Exception, p. 59.
Time, 2 h. 45 min. for post and nuts.
OPERATION.
MACHINES, SPEEDS, rr
FEEDS. TooLS '
File ends square and center to
$* diameter.
Vise, centering ma-
chine, drill, 3500
R.P.M., counter-
sink, 1700 R.P.M.
File, tf drill, 60
countersink.
Rough square, (1), (2), (3),
(4). Take as little as pos-
sible off 1. See 358,
359.
Engine lathe, 12" to
16", 4th or 5th
speed, or 90 F.P.M.
Hand feed.
Round-nose tool ^"
wide, (1), (4),
front tool, (2), (3),
calipers, rule.
Recenter to $" diameter.
Speed lathe, 3d or 4th
speed.
60 countersink.
Finish square, (5), (6), (7),
(8).
Engine lathe, 4th or
5th speed, or 150
F.P.M. Hand feed.
Round-nose tool, (5),
(8), front tool,
(6), (7), calipers,
rule.
Rough turn diameter to fa"
large, (9), (10), (11), (13).
4th or 5th speed, or
90 F.P.M. Fine
power feed 140
to V.
Copper under set
screw of dog, round-
nose tool, calipers,
rule.
Finish turn, (13), (14), to fit
f " gage (easy fit) or use mi-
crometer, tool finish, filing
not necessary. Finish turn,
(15), (16.)
4th or 5th speed, or
150 F.P.M. Fine
power feed 140
to I".
Calipers, rule, f " man-
drel, |" ring gage, or
micrometer.
Chamfer ends 30 to depth of
thread, (17), (18).
Hand feed.
Front tool.
Thread in engine lathe to fit
nuts, (19), (30). See 226,
or
2d or 3d speed, or 25
F.P.M. Arrange
change gears for 24
threads.
U.S.F.-threading tool.
Thread with f X 24 U.S.F. die,
(19), (20). Start in lathe.
Pull belt by hand, and finish
in vise. See 339. If de-
sired, post and nuts may be
threaded f" X 16, United
States Standard thread.
Speed lathe 8* to
12". Vise.
3" universal chuck,
f" X 24 U.S.F.
thread die and die
stock, special vise
jaws.
See Automobile
Screws, 642, 643.
BRASS FINISHING.
185
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Concluded,
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Rechamfer, (21).
Round end with forming tool
Engine lathe, 4th or
5th speed, or 90
F.P.M.
Clamp nut, front tool.
Forming tool
or
By hand tool, (22).
Speed lathe, 4th or
5th speed, or 500
F.P.M.
Planisher or graver.
361. To make brass nurled thumb nuts, Fig. 247.
~^ 5 T
^ (^ ~\ -W*T*
I /S\
J&
FIG. 247. SCHEDULE DRAWING OF NURLED NUTS.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Chuck, drill, and tap nuts, (A),
Speed lathe, 4th or
3" universal chuck,
(B), 336-338.
5th speed, or 1500
planisher or graver,
R.P.M. Vise.
P or f \" drill, r X
24 U.S.F.-thread
tap, tap wrench.
Screw on nut mandrel, mount
Engine lathe, 4th or
Dog, r X 24 U. S. F.
on centers, rough square,
5th speed, or 90 to
thread, nut man-
(C). Finish square, (D).
150 F.P.M. Hand
drel, front tool.
feed.
186
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Concluded,
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Reverse on mandrel, rough
square. (E). Finish square
to thickness, (F).
Rough turn to diameter, 1|",
(G).
Rough and finish turn to di-
ameter, (H). Rough and
finish square to thickness,
(K).
Square and turn nut (B) in
same order as (A), except
leave diameters (L) (31) ^"
large.
Round nut (N) to fit concave
single nurl. See 369.
Nurl (P), also round and
nurl nut (B). See 369.
Hold nut mandrel in chuck,
screw on nut (B), and recess
(R) to fit against 4 on bind-
ing post, Fig. 246.
Screw nuts on binding post,
mount on centers and hand
turn, (S), (T), to correct di-
ameter of post and nut (A) .
File.
Stamp name or initials at end,
(C).
Polish and lacquer posts and
nuts all over, except
threads.
Engine lathe, 4th or
5th speed, or 90 to
150 F.P.M. Fine
power feed 140
to I".
Speed lathe, 4th or
5th speed, or 500
F.P.M.
2d or 3d speed or 300
F.P.M.
4th or 5th speed, or
500 F.P.M.
4th or 5th speed, or
500 F.P.M.
3d or 4th speed, or
250 F.P.M.
Place on metal block.
Highest speed, or 6000
F.P.M. See 321-
323.
Front tool, calipers,
rule.
Round-nose tool, cali-
pers, rule.
Round-nose tool, cali-
pers, rule.
Planisher.
Hand nurling tool.
Chuck, nut mandrel
with thick collar,
planisher or graver.
Clamp nut, round-
nose hand tool.
5" half-round smooth
file.
Steel name stamp,
hammer.
120 and flour emery
cloth, crocus cloth
(an oxide of iron),
rouge (a red iron
peroxide), lacquer,
brush.
MACHINING BRONZE, COPPER, ETC. 187
Attention. The cutting speeds in schedule are for soft brass or
composition castings; but if castings are hard, reduce the cutting
speed.
MACHINING BRONZE, COPPER, ETC.
362. To machine bronze. Phosphor, Tobin, and other
bronzes are tougher than ordinary brass, and are machined
with cutting tools similar to those used for steel and wrought
iron, and lubricated with lard oil.
363. To machine copper. Copper is machined with tools
similar to those used for steel but preferably with more rake
as a keen edge is desirable, and with the point slightly
rounded. Lubricate with milk, soda water, or soap mixture.
Use speed nearly as fast as for brass.
364. To machine aluminium. Aluminium, owing to its
light and ductile nature, is machined with tools having acute
cutting angles, more rake than is used for steel, and at a mod-
erately fast cutting speed. See Lubricants for Cutting Tools,
100. A very high polish may be obtained on a cotton buffing
wheel.
365. To machine Babbitt and lead. Babbitt and lead are
machined dry and with keen tools, the same as aluminium.
366. To machine vulcanite or hard rubber or fiber.
Rubber and fiber are machined dry, at a moderately fast
speed, with cutting tools similar to those used for steel. They
are finished and polished the same as steel, for a very high-
finish buff on a cotton buffing wheel charged with tripoli or
rottenstone.
367. To machine rawhide, use tools similar to those used
for steel, but preferably with more rake and with a cutting
speed about the same as for brass, and machine dry. For
gear blanks, the several layers are confined between riveted
plates, and should be shellacked as soon as machined to pre-
vent swelling. Rawhide is milled and drilled dry, and the
chips are removed by compressed air or a fan.
188
PRINCIPLES OF MACHINE WORK.
NURLING.
368. Hand and machine nurling or milling tools, Figs. 248
and 249, are used to check or mill surfaces of nuts, screw
heads, handles, knobs, etc., to increase the grip and facilitate
rotation. These indentations are similar to those on the edges
of silver and gold coins to detect the removal of metal and
called milled edges.
369. Hand nurling. Fig. 248. Thumb nuts and screw
heads are often nurled with single nurl wheel A and holder B,
Fig. 248. Oil work and nurl.
FIG. 248. HAND NURLING IN SPEED LATHE.
SCHEDULE OF OPERATIONS.
Speed for hand nurling brass,
300 F.P.M.
Speed for hand nurling steel,
200 F.P.M.
Place holder on rest C which
should be firmly clamped, and
place wheel under thumb nut D.
Press down firmly with right
hand, at same time steadying tool
with the left, until desired effect
is produced.
Attention. Use fine nurls on
steel.
NURLING.
370. Machine nurling, Fig. 249.
189
FIG. 249. MACHINE NURLING IN ENGINE LATHE.
SCHEDULE OF OPERATIONS.
Speed for machine nurling iron Feed for nurling, medium
and steel, 40 F.P.M. power feed, 80 to I".
Nurling tool, Fig. 249, con-
sists of holder A and two hard-
ened steel nurling wheels B, B r ,
mounted in head C, connected
with holder by rocking joint.
Nurls have opposed helical teeth
as at D, D'. Holder is fastened
at right angles to work E, and ad-
justed to have both wheels bear
equally on work.
Use power feed. Oil work and
nurls. Start lathe. Force nurls
with cross feed screw hard against
work, preferably with half width
of nurls. Stop lathe, and if
pitch of checking on work is
same as nurls, reduce pressure
and throw in power long, feed to
travel back and forth over surface
until projections come nearly to
a point.
Attention. To prevent hand
or machine nurls from cutting
double set of projections twice as
fine as the nurls and spoiling the
work, press nurls hard at start
until desired effect is produced,
then partially relieve pressure
before starting power feed, to
avoid undue wear on centers and
center holes.
Note. Nurls for hand work
are obtainable in a variety of
patterns; nurls for machine
work, in fine, medium, and coarse
pitches. Medium is most used.
190
PRINCIPLES OF MACHINE WORK.
CURVE TURNING AND FORMING.
371. Curve turning. Small outside and inside rounds
(convex and concave surfaces), ogees and other irregular
curves may be rough formed, as in Fig. 250, with one hand
operating the cross feed and the other the long. feed. The tool
CAST IRON OR BRASS
FIG. 250. CURVE TURNING, OPERATING FEEDS BY HAND. '
for the inside round is moved, approximately to the correct
curve, repeatedly from A to J5; for the outside round, from
C to D and from C to E. By moving one feed more rapidly
than the other, as the curve may require, good results may be
obtained. If the work is slender or the curve large, it is
usually finished with hand tools in the speed lathe (see Tem-
plet, 333). If the curve is small and work stiff, forming
tools may be used.
372. Forming tools for engine lathe work are used for
forming duplicate pieces. They may be made by milling or
filing. If much stock has to be removed, rough form with a
FIG. 251. FORMING WITH FORGED TOOL.
suitable lathe tool. Forming tool A, Fig. 251, is rounding
the end of shaft, after which it may be filed and polished.
Forming tools are also used in turret lathes, screw machines
and planers.
STEADY AND FOLLOWER RESTS.
191
373. Forming cutter and holder. Forming cutters, to
fit thread tool holders, are obtainable. In Fig. 252, forming
cutter A, held in holder B, is forming wheel C.
HAND
WHEEL
FIG. 252. FORMING WITH HOLDER AND CUTTER.
The manufacturing method of machining hand wheel rims
is to mill them with a vertical milling machine or form them in
a special machine which carries a pointed tool mounted on a
turn table around the curve.
STEADY AND FOLLOWER RESTS.
374. A steady rest, Fig. 253, is used to support a slender
shaft to prevent vibration.
SCHEDULE OF PARTS.
A Rest ; two parts, base
and top.
B Base.
C Top, hinged to base.
D Clamp strap.
E Bolt to clamp rest at any
location, on ways of lathe.
F Bolt, hinges top to base.
G Clamp, fastens top to base.
H Sliding jaws adjusted to
spot J on shaft.
K K 2 K s Adjusting screws.
L Nuts to clamp jaws in
position.
192
PRINCIPLES OF MACHINE WORK.
375. To turn spot on shaft, then adjust jaws to that spot
and turn shaft, Fig. 253.
l-K 3
FIG. 253. TURNING SLENDER SHAFT SUPPORTED BY A STEADY REST
SET TO A TURNED SPOT.
SCHEDULE OF OPERATIONS.
True live center. Set dead center in accurate aline ment.
1. Center and straighten shaft,
rough square, recenter, finish
square.
2. Turn spot J &" to ^" large
and wider than jaws H, central
or nearer live center, and file
smooth.
3. Move jaws H back to clear
shaft and swing top C backward.
Mount and clamp rest opposite
spot. Adjust jaws H by screws
K! first, then K 2 to touch shaft.
Swing top C forward and clamp,
and adjust third jaw H by screw
K z . Clamp jaws by nuts L and
oil spot J.
4. Turn one-half shaft, re-
verse shaft, adjust jaws to turned
portion and turn rest of shaft,
or spot the shaft in center and
rough and finish both halves to
spot by reversing shaft, then
move rest along toward live
center, readjust jaws and finish
spot to size.
376. The cat head, Af, Fig. 254, is used to hold slender
shafts to be spotted as well as for steadying slender shafts to
STEADY AND FOLLOWER RESTS.
193
be turned without spotting. It is also used to hold square,
hexagonal, or irregular section work to be turned, as valve
stems that have one part square and the other round.
STEADY
REST
FIG. 254. TURNING SLENDER SHAFT SUPPORTED BY A STEADY REST
SET TO A CAT HEAD.
377. To true cat head on shaft. Place it on shaft and
true up accurately by adjusting screws. Test its truth by
chalk, copper tool, or a test indicator. If the cat head is used
in turning the second end of the shaft, it must be placed on the
turned part and trued up as before. Usually the jaws of the
steady rest are set directly on the shaft for the second half.
Attention. Do not adjust jaws carelessly to cause the
shaft to spring. If piece springs when outside skin is removed,
straighten in a press, or if the shaft is slender, mount on
centers and straighten. Use wooden jaws in steady rests for
finished work.
378. Follower (Traveling) rest, A, Fig. 255, is used for turn-
ing shaft from end to end, and it is more convenient and pro-
duces more accurate work than a steady rest. The rest consists
of two jaws and a frame bolted to carriage B. A spot of the
desired diameter is turned at end C of shaft D, and the jaws
194
PRINCIPLES OF MACHINE WORK
E and E r are adjusted to it. The tool must be slightly in
advance of the jaws, which should be well lubricated where
FIG. 255. TURNING SLENDER SHAFT SUPPORTED By A FOLLOWER REST.
they bear on the work. One-half of shaft is turned, then
it is reversed and the second half turned. For more effective
support, use bushings to suit different diameters of shafts in
place of jaws. When cutting Square or 29 threads on slender
pieces a follower rest is necessary to support the work.
CHAPTER XIV.
CYLINDRICAL GRINDING MACHINES. GRINDING WHEELS.
PROBLEMS IN CYLINDRICAL GRINDING.
CYLINDRICAL GRINDING MACHINES.
379. Machine grinding is a scientific method of producing
cylindrical, conical, and plane surfaces accurately, rapidly,
and economically, with automatic grinding machinery; also
for duplicating parts.
Almost any material, as hardened and soft steel, wrought
iron, cast iron, brass, copper, aluminium, vulcanite, and wood
fiber, may be ground accurately. Grinding machines are
not designed to remove a large amount of stock but to produce
accurate dimensions on work that has been roughturned.
The principle of grinding on two dead centers. Ground
work is more accurate than turned work. This accuracy is
obtained by grinding the work on two dead centers as in
AD CENTER PULLEY
EMERY WHEEL-! * CENTER
FOOT
CENTER STOCK
1
FIG. 256. ACCURACY OBTAINED BY GRINDING ON Two DEAD CENTERS.
Fig. 256, which eliminates the error caused by wear of spindle
bearings. The wear of dead centers is readily corrected by
grinding the centers, but the wear of spindle bearings cannot
be readily corrected.
Machine grinding is also used for finishing as a substitute
for polishing as it is more economical than using files and
emery cloth.
195
196
PRINCIPLES OF MACHINE WORK.
380. Grinding machines may be divided into four general
classes: Universal grinding machines for general work; plain
grinding machines for outside work only; cutter grinding
machines for grinding cutters and similar work; and surface
grinding machines for surface grinding only.
Special grinding machines are designed for special purposes,
as internal grinding machines, piston grinding machines, and
crank grinding machines to rough as well as to finish auto-
mobile crank shafts without rough turning.
381. Universal grinding machine, Fig. 257, like the engine
lathe, is designed for general work, as straight and taper grind-
ing, both external and internal, facing sides of disks, grind-
ing clearances on cutters, reamers, etc. See Internal, Cutter
and Surface Grinding, Advanced Machine Work.
SCHEDULE OF PARTS.
COUNTERSHAFT DRIVE. BELT FEED.
382. Machine Parts.
A Base, contains locker for
small parts.
B Bed, contains feed and
reversing, mechanism.
C Table.
C" Swivel table.
D Swivel headstock (90),
position adjustable.
E and E' Dead centers.
F and F' Dead center pulleys ;
large or small may be used.
G Live spindle pulley.
H Stop for live spindle
pulley.
J Footstock, position ad-
justable.
K Lever to spring dead
center " in " or " out."
L Grinding wheel, head
mounted on swivel slide and
adjustable " forward " or " back-
ward ; " it can also be fed by
hand to grind steep tapers.
M Grinding wheel.
N Water supply pipe.
P Belt to drive work.
Q Belt to drive grinding
wheel.
R Belt to drive feed cone.
S Belt to drive pump.
383. Countershaft Parts.
I. Line shaft.
II. Tight and loose pulley
mechanism controlled by shipper.
III. Belt to drive sleeve carry-
ing feed cone.
IV. Belt to drive work drum.
V. Work drum.
VI. Clutch operated by ship-
per brake.
VII. Belt to drive grinding
wheel drum.
VIII. Grinding wheel drum.
IX. Belt to drive dead center
pulley F to give higher speed.
X. Belt to drive live spindle
pulley G.
CYLINDRICAL GRINDING MACHINES.
197
WATER
SUPPLY
PIPE
-S N
DEAD
CENTER
PULLEY
F
FIG. 257. UNIVERSAL GRINDING MACHINE.
198 PRINCIPLES OF MACHINE WORK.
GRINDING WHEELS.
384. Grinding wheels, Chart, Fig. 258, are made from
various abrasives, emery, corundum, alundum, and car-
borundum. The abrasive is mixed with a bond, the amount
and composition of which makes a wheel hard or soft and
determines its grade or degree of hardness.
They are molded, baked, turned, balanced, and tested for
hardness and speed.
The number of a wheel is determined by the number of
meshes per linear inch of the sieve through which the abrasive
has passed, and for grinding wheels runs from No. 12 to
No. 120. Lower numbers indicate coarser wheels and higher
numbers finer wheels. See Elements of Machine Work.
385. Coarseness. Grade of Hardness.
Coarseness determined by Hardness determined by bond
No. of abrasive. binding grains of abrasive
together.
Processes.
Vitrified. Tanite.
Silicate. Vulcanite.
Elastic. Celluloid.
Each process is best adapted to certain classes of grinding,
yet each may be used for general grinding.
386. Vitrified wheels, reddish brown in appearance, are
made by mixing the abrasive with a bond of clay, sand, spar,
etc., they are then molded into shape, placed in ovens similar
to pottery kilns and subjected to a prolonged and intense heat
(3000 F.). These wheels are even in texture, open and po-
rous. They are especially adapted to grinding hardened steel,
as they will not glaze easily and are thus cool-cutting. Wheels
made by this process are used for general work and for cylindri-
cal and cutter grinding, See Table of Grades, 393.
CHART OF GRINDING WHEELS
ABRASIVE
PROCESS
EMERV CORUNDUM ALUNOUM CARBORUNDUM
VITRIFIED SILICATE ELASTIC
EXTERNAL
SPINDLE.SHAFT, SPINDLE.SHAFT ROLL GAS ENGINE
MANDREL.GAGE SHOULDER SHAFT CRANKSHAFT
J 234
SURFACE
5
LATHE AND UNIVERSAL
PLANER TOOL TOOL
6 7
FLAT CUTTER
AND SURFACE
KNIFE AND
SURFACE
GEN.
TOOL
10
CUTTER
14
RADIAL CUTTER CUTTER AND FORMED
AND REAMER STRAIGHT EDGE CUTTER
15
16
GEAR
CUTTER
18
CUTTING
OFF
19
20
GROOVE CALIPER
AND FLUTE GAGE
21 22
GOUGE
23
INTERNAL
GAS ENGINE GEN.
CYLINDER INTERNAL
24 25 26
DIE
27
FIG. 258.
(199)
200 PRINCIPLES OF MACHINE WORK.
387. Silicate wheels, light gray in appearance, are made by
mixing the abrasive with a bond of silicate of soda, and then
subjecting to a low heat (300 to 400 F.). These wheels are
made porous or dense, as desired, are even in hardness and
have unusual strength. They are adapted for wet tool grind-
ing and general purposes. All wheels above 30" in diameter
are made by this process. See Table of Grades, 393.
388. Elastic wheels, black in appearance, are made by
mixing the abrasive with a bond of shellac, etc.; and then
subjecting to a low heat (300 to 400 F.). These wheels are
not brittle, and can be made as thin as &". They are used for
grinding arbors, cutters, reamers for saw gumming, and for
cutting off small stock, such as thin steel tubing, wire, etc.,
also for grinding in narrow openings. See Table of Grades,
393.
389. Tanite wheels are made by mixing the abrasive with
tanite (a chemical and mechanical transformation of leather)
and then subjecting to heat under hydraulic pressure. They
are used for general grinding in a similar manner to silicate
wheels.
390. Vulcanite wheels are made by mixing the abrasive
with a bond of rubber and sulphur, and subjecting to a low
heat (225 F.). These wheels are not brittle and have a high
factor of safety. They are used for special work.
391. Celluloid wheels, brown in appearance, are made by
mixing the abrasive with celluloid; both are subjected to a
low heat (250 F.).
392. Combination wheels are made by mixing several
numbers of the abrasive together in the formation of the
wheel. Three numbers are generally used for this purpose,
as 24, 36, 46, the coarsest grade is used for fast cutting
and the finest grade is used for a smooth finish. The addi-
tion of a small amount of fine abrasive to a coarse wheel will
produce wheel of great durability.
GRINDING WHEELS.
201
393. Table of Grades of Wheels Made by Different
Processes,
VITRIFIED
PROCESS.
SILICATE
PROCESS.
ELASTIC
PROCESS.
Very soft. . .
E
f
IE
F
1
1 E
G
H
HE
H
H
HE
Soft
I
if
IfE
J
2
2 E
K
2i
2^ E
L
2*
2E
Medium ....
M
3
3 E
N
a*
3 E
4
4 E
P
4
4 E
Hard
Q
5
5 E
R
S
6
6 E
T
6*
6E
Very hard . .
U
7
7 E
Attention, The grade of a grinding wheel is more important than
the number of the abrasive. The number influences the grade to a
slight extent, a fine wheel, as No. 90, grade M, is slightly harder
than a coarse wheel same grade as No. 60, grade M.
394. Shapes of wheels. Plain disk wheels are used for
straight and taper work, and plain and cup wheels for surface
grinding.
Cup, bevel, and disk wheels are used for grinding drills,
cutters, and for grinding to shoulder. Small wheels are used
for internal grinding. See Chart of Grinding Wheels, Fig. 258.
395. Selection of wheel depends on hardness of material
and nature of work. In general, use a hard wheel for rough
grinding and a medium or soft wheel for accurate grinding
and fine finish. If a wheel is too hard-, it will glaze quickly
and heat the work; if too soft, it will wear rapidly and prevent
accurate grinding. A coarse wheel is less liable to heat than a
fine wheel, as the latter is apt to glaze. A perfect wheel is
one with a bond that will release the grains before glazing
takes place, and hard enough to take a series of cuts without
202
PRINCIPLES OF MACHINE WORK.
changing its shape or diameter, as accurate grinding depends
upon the sizing power of wheel.
396. To mount wheels. Place rubber or blotting-paper
washers between wheels and flanges, and clamp. Wheels
should fit easily on arbors. Some are bushed with soft metal
to fit standard shafting and will run fairly true. Wheels to
be interchangeable without truing are provided with indi-
vidual taper bushings. Small wheels for internal grinding
have counterbore depressions for fillister head screws.
397. The periphery speed for wheels should be approximately
from 5000 to 6500 feet per minute (F.P.M.). A higher speed
may cause the wheel to break. Should a wheel heat or glaze,
run it slower. If it is too soft, it can often be made to hold
its size by using a higher speed.
TABLE OF SPEEDS FOR GRINDING WHEELS.
The table given below designates number of revolutions per
minute for specified diameters of wheels, to cause them to run
at the respective periphery rates of 4000, 5000, and 6000 feet
per minute.
DIAM. WHEEL.
REVOLUTIONS PER
MINUTE FOB SUR-
FACE SPEED OF
4000 FT.
REVOLUTIONS PER
MINUTE FOR SUR-
FACE SPEED OF
5000 FT.
REVOLUTIONS PER
MINUTE FOR SUR-
FACE SPEED OF
6000 FT.
1 inch.
15,279
19,099
22,918
2 "
7,639
9,549
11,459
3 "
5,093
6,366
7,639
4 "
3,820
4,775
5,730
5 "
3,056
3,820
4,584
6 "
2,546
3,183
3,820
7 "
2,183
2,728
3,274
8 "
1,910
2,387
2,865
10 "
1,528
1,910
2,292
12 "
1,273
1,592
1,910
14 "
1,091
1,364
1.637
16 "
955
1,194
1,432
18 "
849
1,061
1,273
20 "
764
955
1,146
22 "
694
868
1,042
24 "
637
796
955
30 "
509
637
764
36 "
424
531
637
GRINDING WHEELS. 203
398. The periphery speed of work (F.P.M.) should be pro-
portional to the grade and speed of wheel, also to the diameter
of work. The speed varies from 15 to 60 feet per minute for
different classes of work. The higher speed is best for cast
iron and the lower for duplicate work.
399. Direction of rotation of wheel and work must be op-
posite at cutting point as in Fig. 259.
FIG. 259. DIRECTION OF ROTATION OF WHEEL
AND WORK FOR EXTERNAL GRINDING.
400. Feed of table or traverse speed is in proportion to > the
width of wheel face and finish required. Use coarse feed for
roughing. For large work with a heavy machine, use one-half
to three-fourths width of wheel to each revolution of work; on
light machines use one-third to one-half width of wheel. For
a very fine and accurate finish, use one-fourth to one-third
width of wheel.
401. Depth of cut. For roughing take deep cuts, .001"
to .004" at each stroke; for finishing light cuts, .00025" to
.0005" at each stroke. The sparks thrown off by the grinding
wheel indicate the depth of cut: a large volume of sparks indi-
cates a heavy cut, and a small volume a light cut.
402. Width of face of wheel. A wide wheel with a coarse
feed, removes stock rapidly, and is used where it can pass
from one-fourth to one-half its width beyond the end of work
or recess.
A narrow wheel is used to grind to a shoulder not recessed
to produce an accurate diameter next to shoulder or with
narrow recess. The face of a wheel may be narrowed by
beveling a corner with a diamond tool.
403. To true grinding wheel. Grinding wheels wear smooth
or become glazed by use, so that they will not cut freely. A
new wheel will not run true and must be trued before using.
204 PRINCIPLES OF MACHINE WORK.
To true face of wheel, mount diamond tool A, Fig. 260, in
fixture B. Feed tool to touch revolving wheel with cross
feed, then traverse tool by power or hand long. feed. To true
UNIVERSALGRINDING MACHINE
UNIVERSAL GRINDING MACHINE
FIG. 260. TRUING FACE OF WHEEL FIG. 261. TRUING SIDE OF WHEEL
WITH A DIAMOND TOOL. WITH A DIAMOND TOOL.
side of wheel, clamp diamond tool A, Fig. 261, in slide of fixture
B at right angles to wheel. Feed tool to wheel by hand long,
feed until it touches revolving wheel, then operate tool by
hand with cross "feed.
If a wheel is soft, but little attention may be given it while
roughing, as it will wear away fast enough to keep sharp, but
it must be sharp and also true, to produce a fine finish.
Attention. Grinding wheels may be trued dry, but the
wear on the diamond tool is much less if plenty of water is
used.
404. To true centers, Fig. 262. Remove centers, clean
holes with waste. Clean dead center and insert it in live
center spindle. Belt machine to revolve live spindle, pull out
pin A, swivel headstock to 30 and clamp. Set reversing dogs
and grind center by trial and correction to fit center gage
(60). See 33. Replace dead center, clean and insert live
center, in its spindle and grind. Both centers are hardened
and tempered. In a plain grinding machine, use a special
attachment. Some small grinding machines permit swinging
of table to grind centers.
GRINDING WHEELS.
205
FIG. 262. GRINDING THE CENTER OF UNIVERSAL GRINDING
MACHINE.
405. Methods of driving work. (Two dead centers..)
Centered work is ground on two dead centers and driven by
dead center pulley and balanced dog, as in Fig. 256. To
FIG. 263. END DRIVING DOG FOR WORK OF ONE DIAMETER.
grind work of one diameter, use end driving dog, as in Fig.
263. (With revolving spindle.) For work held in chuck, as
face and internal grinding, the spindle revolves.
Some classes of centered work may be rapidly handled and
ground by using spindle and triangular live center drive, as
in Fig. 264.
206
PRINCIPLES OF MACHINE WORK.
EMERY
WHEEL
FIG. 264. TRIANGULAR CENTER DRIVE FOR RAPID PRODUCTION.
A triangular center punch is driven lightly into one center
hole to make it fit center. The work is then mounted on
centers and not moved until finished.
406. To set swivel table to grind straight work. Set both
zero lines on headstock swivel (graduated in degrees) to coin-
cide, then set both zero lines on swivel table (graduated scale
in inches per foot and degrees) to coincide. To obtain accu-
rate setting, take a few light cuts and caliper both ends with
micrometer. If they differ, release clamp bolts and swing
swivel table a little with adjusting screw at end, clamp bolts
and repeat above process until desired accuracy is obtained.
Attention. The graduations on headstock swivel and
swivel table are helpful, but the coincidence of lines, even if
located with a magnifying glass, give only approximate accu-
racy, and it is only by the process of trial and correction that
accuracy is obtained.
407. Slight tapers are obtained by setting swivel table to
approximate taper by scale and using a standard taper ring
gage to determine exact taper, which is obtained by trial and
correction in the same manner as a straight setting.
408. Steep tapers on work held in chuck or on headstock
spindle are obtained by swiveling the headstock. For work
mounted on centers, tapers are obtained by setting wheel slide,
and for two abrupt tapers, outside or inside, by setting both
headstock and wheel slide at proper angles.
409. Wet and dry grinding. Wet grinding is rapid and
accurate. An insufficient or fluctuating supply of water will
cause a change of temperature and produce inaccurate work.
GRINDING WHEELS. 207
If the nature of the work will not permit, or the machine is not
arranged for wet grinding, good results may be obtained by
grinding dry with very light cuts. Water guards for wet
grinding are supplied. See A, Fig. 265.
410. Lubricants for grinding. Use water, and to prevent
rusting of machine, add enough sal soda to the water to show
a deposit on machine. Machine oil is sometimes added to
mixture.
Aluminium is ground with a lubricant of kerosene, or a
mixture of kerosene and machine oil.
As most cutter grinders are not arranged for wet grinding,
cutters and reamers are ground dry.
411. To prepare work to be ground. Allowance for grind-
ing. Short work that is not to be hardened is rough turned
from .006" to .010" large. For large work and long, slender
work that will spring and run out of true after turning, and for
hardened steel that is liable to spring in hardening, it is good
practice to allow from .020" to .030" to grind off. A large
allowance means but one cut in the lathe, and it is more eco-
nomical to grind with the modern grinding machine than to
take a second cut in the lathe to reduce the allowance.
412. Rough and finish grinding. In manufacturing ma-
chine parts in lots, it is good practice to rough grind all
pieces to within .002" or .003" before finishing any. The
wheel then need be trued only twice, once in roughing
and once for finishing.
413. The finish of work. An ordinary shaft should be
given a " commercial " finish; that is, it should be ground
to a good smooth surface. A forcing fit need not be ground to
such a fine finish, but close to size. Gages and fine work of
this class must be ground both to a fine finish and to an exact
size. A fine accurate finish is generally obtained with light
cuts, slow feed, a true wheel, and a liberal supply of water.
414. Expansion of work while grinding. Expansion is
caused by the friction of the wheel. In grinding work dry,
particularly long shafts, it sometimes is made to run out of
208 PRINCIPLES OF MACHINE WORK.
true and this is due to its own internal strains or unequal
expansion. A grinding operation shows error or truth; an un-
even volume of sparks indicates error, and an even volume of
sparks truth of work. To remedy this, flood work with water,
reduce speed of work and feed one-fourth thousandth at each
end of stroke until work is cylindrically true. When the work
becomes round again, increase its speed and the depth of cuts.
Spring back rests B, B, B. Fig. 273, are often used to remedy
this error.
Attention. A distinct difference in the sparks, however,
may indicate an error as small as one-tenth to one-fourth
thousandth of an inch or less, which may be ignored for some
classes of work.
415. Seasoning work. Long slender work is often laid
away for a period of time between roughing and finishing, to
relieve internal strains, when great accuracy is required. This
is usually unnecessary for short or heavy work.
416. Care of machine and work. All bearings should
be kept well oiled. The cross slide should be cleaned, oiled, and
if need be, adjusted to move smoothly. The centers and center
holes in work must be kept absolutely true and clean and well
oiled to produce accurate work. While most of the bearings
on modern grinding machines are dust-proof, nevertheless the
machines should be kept clean.
417. Measuring tools for grinding Use micrometer calipers
and limit gages for general work. For very accurate work
use a ten-thousandth micrometer or measuring machine.
Warning. Push the shipper slowly and watch the grind-
ing wheel as it slowly starts. Never stand in front of a wheel
when it is starting, to avoid injury if the wheel should happen
to break. Modern grinding wheels have a high factor of safety
and seldom burst at the speed recommended, but any wheel
may be broken by careless usage; accidentally moving the
headstock, or footstock, or work, against the side of the wheel,
especially a thin, vitrified wheel, revolving or stationary, may
break it.
PROBLEMS IN CYLINDRICAL GRINDING.
209
PROBLEMS IN CYLINDRICAL GRINDING.
418. Adjustments and movements to operate universal
grinder, Fig. 265.
SCHEDULE OF PARTS.
1. Shipper to start and stop
grinding wheel.
2. Shipper brake to start and
stop work.
3. Knob to start or stop long,
power feed work (table feed).
4. Long, feed hand wheel.
5. Lever to reverse long, feed
by hand.
6 and 7. Dogs to reverse long,
feed automatically.
8. Cross feed hand wheel.
Automatic Cross Feed.
9. Pawl.
10. Ratchet wheel (each tooth
reduces work 1/4/1000" in diam-
eter and each graduation 1/1000").
11 and 12. Adjusting screws
which control movements of pawl
9 and depth of cut at each end of
stroke.
13. Perpendicular latch.
14. Latch head.
15. Shield.
16. Horizontal latch.
Swivel Table.
17 and 18. Bolts to clamp
swivel table.
19. Screw to adjust swivel
table. To grind straight or taper,
see Graduated Scale at end of
swivel table.
UNIVERSAL GRINDING MACHINE
FIG. 265. GRINDING A RUNNING FIT.
210
PRINCIPLES OF MACHINE WORK.
419. To grind I T V" running fit (wet), universal grinding
machine, Fig. 266.
I*
1^5 RUNNING FIT
ROUGH
GRIND
,
TURNED
1.0620"
c*'
1.078"
1.0616"
SHAFT BLANK MACHINE STEEL @
FIG. 266. SCHEDULE DRAWING OF GRINDING A RUNNING FIT.
SCHEDULE OF OPERATIONS.
ROUGHING. FINISHING.
Shaft blank, machine steel, rough turned 1.0780" diameter.
Corundum grinding wheel VI" X ", No. 54, Grade M, vitrified.
Speed of wheel 5000 F.P.M. Speed of work 50 F.P.M. Feed
\ width wheel per revolution.
Oil bearings of machine with machine oil.
True wheel (see 403) and centers (see 404). Set machine to
grind straight. See 406.
Time, 20 min. with machine " set up."
1. Grind to diameter, (11).
Arrange water guards A, Fig. 265,
for grinding.
2. Unlock horizontal latch 16,
from latch head 14 throw out
pawl 9 and move grinding wheel
back with cross feed wheel 8, then
mount shaft B on centers. Use
special grinding dog C with copper
under set screw. Start wheel,
work and feed 1, 2, 3, and ad-
just table dogs 6 and 7 to obtain
length of stroke and avoid wheel
striking dog or footstock.
3. Set automatic cross feed at
11 and 12 to feed T 7jW" at each
end of stroke (4 teeth on ratchet).
Move grinding wheel to lightly cut
revolving work with hand cross
feed wheel 8. Throw pawl 9 to
mesh with 10, and take about two
trial cuts entire length of work.
4. Throw out pawl 9 and
allow wheel to pass over work
several times until cutting nearly
dies out without moving cross
feed, then stop work with grind-
ing wheel at footstock end with
shipper brake 2, and measure
work with 2" micrometer.
Subtract rough diameter of
work 1.0620" + .002" for finish-
ing from reading of micrometer.
For example, reading of microm-
eter may be 1.0740"; then 1.0740"
- 1.0640" = .0100" for rough
grinding. As each tooth in ratch-
et wheel 12 = 1/4/1000" in diam-
eter of work and work is .010"
large, the work is 40 teeth large.
5. Rough grind .002" large as
follows : Raise perpendicular latch
13 in head 14, and without moving
cross feed, move shield 15 to right
PROBLEMS IN CYLINDRICAL GRINDING.
211
SCHEDULE OF OPERATIONS. Concluded.
until end of shield and pawl tooth
are 40 teeth apart, then drop in
latch 13. Start work (2) when
shield 15 throws out pawl 9,
stop work and measure, and
from reading subtract 1.0620".
(1.0640"- 1.0620" = .002".)
6. Finish grind with pinch
feed 1/4/1000" in diameter of
work as follows : Lock latch head
14 with latch 16, start work.
Take two cuts 1/2/1000" each
(two pinches at each end of work).
Stop work and measure (1.0630").
Take one cut 1/4/1000" (one pinch
at footstock end of work) and
measure and repeat until work
measures 1.0620".
Limit 1.0620" to 1.0615".
This shaft is for a running
fit in ITS" hole. Hole limit
1 .0625" + or - .00025". See Run-
ning Fits, 137. Clean machine
with waste.
Attention. After the student has ground a number of problems
and become familiar with the behavior of machine and the automatic
feed, he may let wheel pass over work after trial cuts until cutting
sparks die entirely out, then set automatic feed to finish grind to diam-
eter without using pinch feed except for wear of wheel.
Note. The student should examine wheel and centers and,
if in good condition, truing may be omitted.
420. Adjustments and movements to operate universal and
tool grinding machine, Fig. 267.
SCHEDULE OF PARTS.
1. Shipper to start and stop
grinding wheel.
2. Shipper brake to start and
stop work.
3. Lever to start or stop long,
power feed (table feed).
4. Long, feed hand wheel.
5. Lever to reverse long, feed
by hand.
6 and 7. Dogs to reverse long,
feed automatically.
8. Cross feed hand wheel.
Each graduation reduces work
1/1000" in diameter.
Fine Cross Feed.
9. Thumb nut for controlling
fine or coarse cross feed.
10. Thumb screw for operat-
ing fine cross feed.
Swivel Table.
17. Bolt for clamping swivel
table.
18. Spring knob for quick
adjustment of swivel table.
19. Thumb screw for fine ad-
justment of swivel table. To
grind straight or taper, see Grad-
uated Scale at end.
Grinding Wheels.
20.. Hand wheel to elevate
grinding wheel.
212
PRINCIPLES OF MACHINE WORK
UNIVERSAL AND TOO!. GRINDING MACHINE
CORUNDUM WHEEL 8O K VITRIFIED
FIG. 267. GRINDING A FORCING FIT.
421. To grind i" forcing fit (dry) with a universal and
tool grinding machine, Fig. 267.
1
H FORCING FIT
;>
ROUGH
TURNED <
1.015"
GRIND
1.0026*
1.0020"
SHAFT BLANK MACHINE STEEL (J2)
FIG. 268. SCHEDULE DRAWING OF GRINDING A FORCING FIT.
SCHEDULE OF OPERATIONS.
ROUGHING. FINISHING.
Shaft blank, machine steel, rough turned, 1.015" diameter.
Corundum grinding wheel 1" X ", No. 80, Grade K, vitrified.
Speed of wheel 5000 F.P.M. Speed of work 50 F.P.M. Feed
width wheel per revolution.
Oil bearings of machine with machine oil.
True wheel and centers. Set machine to grind straight.
Time, 23 min. with machine "set up."
1. Grind to diameter,
Fig. 268. Loosen nut 9, Fig. 267,
and move grinding wheel back
with cross feed wheel 8, then
mount shaft B on centers. Use
grinding dog C with copper under
PROBLEMS IN CYLINDRICAL GRINDING.
213
SCHEDULE OF OPERATIONS. Concluded.
set screw. Start grinding wheel,
work and feed 1, 2, 3, and adjust
dogs 6 and 7 to obtain length of
stroke of portion D and avoid
wheel touching shoulder of work.
2. Move grinding wheel to
lightly cut revolving work with
coarse hand cross feed wheel 8.
Tighten nut 9 and use fine cross
feed thumb screw 10. Gradu-
ations on cross feed reduce work
1/1000" in diameter. Take two
or three trial cuts 1/2/1000" each,
feeding at footstock end only, and
allow wheel to pass over work
until cutting nearly dies out, then
stop table and work with grinding
wheel at footstock end with ship-
pers 3, 2, and measure work with
a 1" micrometer.
3. Rough grind .002" large as
follows: Use 1/2/1000" cuts with
thumb screw 10 at footstock end
only, and grind to 1.0025" + .002"
= 1.0045".
For example, reading of mi-
crometer may be 1.012", then take
8 cuts and measure (1.008");
take 4 cuts and measure (1.0060") ;
take 3 cuts and measure (1.0045").
4. Finish grind as follows : Use
1/4/1000" cuts and feed at foot-
stock end only, as follows: Take
2 cuts and measure (1.0040") ; take
3 cuts and measure (1.00325") ;
take one cut and measure, and
repeat until work measures
1.0025".
Limit 1.0025" to 1.0020".
Attention. It is to be forced
into a 1" hole. Hole limit 1.000" +
or - .00025". See Forcing Fits,
140.
Clean machine with brush and
waste.
u
UNIVERSAL GRiNOiNQ MACHINE
CORUNDUM
WHEEL
6OKORU
FIG. 269. GRINDING A MANDREL.
422. To grind a &" standard mandrel, taper .006" to i',
Figs. 269 and 270.
214
PRINCIPLES OF MACHINE WORK.
j^a J
DIA.
GRIND TAPER .006" TO r OF
V. END
.56200"l _
.5$175"J
*>- *
C e *n
FIG. 270. SCHEDULE DRAWING OF GRINDING &" STANDARD MANDREL.
SCHEDULE OF OPERATIONS.
ROUGHING. FINISHING.
Mandrel blank, carbon steel, smooth turned .580" diameter.
Stamped, hardened, and ends tempered. See Elements of Machine
Work.
Corundum grinding wheel 12" X %*, No. 60, Grade K or L, vitrified.
Speed of wheel 5000 F P.M. Speed of work 50 F.P.M. Feed
width of wheel per revolution.
. Oil bearings of machine with machine oil.
True wheel and centers. Set swivel table to grind the taper.
Time, 20 min. with machine "set up."
1. Lap center holes, (16),
(17). See Attention 310. Grind
to taper, (18). Grind to diam-
eter, (19). Arrange water guards.
See Fig. 265.
2. Move grinding wheel back
with hand cross feed wheel 8.
Mount mandrel B on centers
with dog C on stamped end
without copper under sst screw.
Start grinding wheel, work and
feed (1, 2, 3), and adjust dogs 6
and 7 to length of stroke.
3. Set automatic feed at 11
and 12 to feed 1/1000*, four teeth
at each end of work. Move grind-
ing wheel to lightly cut revolving
work with hand cross-feed wheel
8, then throw pawl 9 in mesh and
take three or four cuts with auto-
matic feed. Then throw out pawl
9 and allow wheel to pass over
work until cutting nearly dies out.
Then stop work with grinding
wheel at footstock end and meas-
ure both ends with micrometer.
To correct taper, unclamp nuts 17
and IS and move swivel table by
screw 19 ; take one or two cuts with
automatic cross feed. Measure
and repeat until taper is correct.
4. Rough grind .002" large, as
follows: Measure small end, then
subtract roughing diameter .562"
+ .002" for finishing from read-
ing of micrometer. For example,
reading of micrometer may be
.574" - .564" = .010" for rough
grinding. Set shield 15 and pawl
9, 40 teeth apart and. drop in latch
13. Start work (shipper 2), and
when machine stops feeding, stop
work and measure, and from read-
ing subtract .562" (.564" - .562" -
.002").
5. Finish grind with pinch
feed as follows: Lock latch head
14 with horizontal latch 16.
PROBLEMS IN CYLINDRICAL GRINDING. 215
SCHEDULE OF OPERATIONS. Concluded.
Start work and pinch feed to
finish. Take two cuts 1/2/1000
each (two pinches at each end of
work), stop work and measure.
Take one cut 1/4/1000" (one
pinch) at footstock end of work
and measure and repeat until
work measures .562". Limit
.56200" to .56175".
Clean machine with waste.
423. To grind a shoulder, Fig. 271.
Spindle blank, crucible cast steel.
Alundum grinding wheel (plain) 12" X J", No. 60, Grade K,
vitrified.
Speed of wheel 5000 F.P.M. Speed of work 50 F.P.M.
Feed, J width of wheel.
True wheel and centers. Set machine to grind straight.
Mount spindle blank A, recessed as at B for side clearance,
on centers. Control depth of cut by long, feed, and feed by
UNIVERSAL GRINDING MACHINE
ALUNDUM WHEEL 60 K VITRIFIED
FIG. 271. GRINDING A SHOULDER.
cross feed. If shoulder is large use special wheels mounted
on end of wheel spindle C and set wheel swivel J from 90 to
give clearance.
424. Plain grinding machine for commercial grinding,
Fig. 272. The essential parts of this machine are similar to
those of a universal grinding machine except that the head-
stock and wheel slide do not swivel, and the swivel table forms
a water guard. It is designed for straight and taper outside
work only. It is made strong and rigid to grind work rapidly.
216
PRINCIPLES OF MACHINE WORK.
Some plain grinding machines have a traveling grinding
wheel instead of a traveling table.
425. To grind cast-iron roll, A, Fig. 272.
Roll blank, cast iron. Rough turned .010" to .020" large.
Alundum grinding wheel (plain) 20" X 2", No. 24 Combi-
nation, Grade K, vitrified.
Speed of wheel 5000 F.P.M. Speed of work 50 F.P.M.
Feed, f width of wheel.
True wheel and centers. Set machine to grind straight.
PLAIN GRINDING MACHINE
FIG. 272. GRINDING A CAST-IRON ROLL.
Set automatic feed to feed at both ends of stroke and to
grind .002" large, then use pinch feed to finish.
Mount roll A on dead centers.
Place universal back rests 6 to 10 diameters apart and grind
to required diameter with water.
426. To grind slender shaft, A, Fig. 273.
Shaft blank, machine steel smooth turned .012" large.
Alundum grinding wheel (plain) 12" X J", No. 60, Grade L,
vitrified.
PROBLEMS IN CYLINDRICAL GRINDING.
217
Speed of wheel 7000 F.P.M. Speed of work 90 F.P.M.
Feed, J width of wheel.
True wheel and centers. Set machine to grind straight.
Set automatic feed to feed at both ends of stroke and to
grind .002" large, then use pinch feed to finish.
Mount shaft A on dead centers. Place three universal
back rests B against shaft, 6 to 10 diameters apart, see Fig. 273,
and grind to required diameter.
PLAIN GRINDING MACHINE
ALUNDUM WHEEL
COMMERCIAL GRINDING
60 L VITRIFIED
FOLLOWER
REST
c
FIG. 273. GRINDING A SLENDER SHAFT.
427. Back rests, plain and universal, are fixtures used to
reduce vibration and permit a greater depth of cut on straight
and taper work both large and small.
The plain rest has a single shoe of wood or soft metal and is
used for small, short work.
The universal rests B, B, B can be delicately adjusted.
Select bronze shoes 1, 1, 1, (see detail) the size of finished
work, move screws 2 to maintain contact of shoe upon work
while grinding trial piece, and adjust stop screw 3 to preserve
diameter when finished.
Adjust screws 4 and 5 to regulate pressure of springs upon
shoes and work.
218
PRINCIPLES OF MACHINE WORK.
Duplicate pieces are ground without disturbing adjustments
except slightly for wear of shoe 2 and diameter 3.
Follower rest C is used on slender work that has been rough
ground .001" large. It cannot be used on taper work. Adjust
with wheel and work in motion.
428. Automatic magnetic sizing grinder, Fig. 274. -
The mechanical automatic feeding mechanism is electrically
controlled and duplicates straight and taper work regardless
of wear of grinding wheel.
A coarse feed for roughing automatically switches to a fine
feed for finishing, and when work is finished to size the feed
automatically stops.
429. To rough and finish grind spindles in an automatic
magnetic sizing grinder, Fig. 274. Duplicate work. -
Spindle blank, machine steel, rough turned 0.020" large.
Corundum grinding wheel (plain) 18" X H", No. 40, Grade
M, vitrified.
Speed of wheel 5000 F.P.M. Speed of work 50 F.P.M.
Feed, } width of wheel.
True wheel and centers. Set machine to grind straight.
WORK
MACHINE STEEL
SHAFT
PLAIN GRINDING MACHINE
SET TO TAKE FINISHING CUT
SIZING
CORUNDUM
WHEEL
54 COMB.M
VITRIFIED
FIG. 274. AUTOMATIC SIZING DEVICE FOR GRINDING DUPLICATE WORK.
PROBLEMS IN CYLINDRICAL GRINDING. 219
To set automatic sizing device, rough and finish grind one
piece to required size with automatic mechanical feed, and use
this as a master piece to set sizing device. Place diamond-
point bearer A, on master piece B and adjust arm C by screw
D to make an electrical contact. Then mount blank for next
piece on centers. Adjust coarse feed for roughing by screw E
to feed .001" at each end of stroke, and adjust screw F to
have magnet G throw out the coarse and throw in the fine
feed one tooth (one-eighth thousandth) when piece is within
.002" of size.
Magnet H throws out latch J and stops feed when piece is
gound to correct diameter.
Attention. The coarse and fine feeds and the amount
allowed for finishing may be varied for different classes of
work. Dry batteries or a plug in a lamp socket of a direct-
current circuit will operate device.
430. To grind a straight and taper bearing on a spindle,
Fig. 275.-
Spindle blank, crucible steel unannealed. Rough turned
.010" to .020" large.
Corundum grinding wheel (plain) 12" X 1", No. 54, Grade M ;
vitrified.
Speed of wheel 5000 F.P.M. Speed of work 50J?.P.M.
Feed, J width of wheel.
True wheel and centers.
PLAIN GRINDING MACHINE
FIG 275. GRINDING A TAPER SPINDLE.
220
PRINCIPLES OF MACHINE WORK.
Set automatic feed to feed .001" at both ends of stroke and
to grind .002" large, then use pinch feed to finish.
Mount spindle A on dead centers.
Place two universal back rests B and B' against straight
portions of work. After straight portions are ground, set
swivel table to grind taper bearing C. To obtain correct
taper, take light cuts, try taper in box and adjust table until
taper fits. Use " artists ' " blue for marking in taper hole.
431. To grind taper collet, A, Fig. 276.
Collet blank, machine steel. Rough turned .010" to .020"
large and recess at B.
Corundum grinding wheel (plain) 12" X i", No. 54 Combi-
nation, Grade M, vitrified.
Speed of wheel 5000 F.P.M. Speed of work 50 F.P.M.
Feed, f width of wheel.
True wheel and centers.
UNIVERSAL GRINDING MACHINE
CORUNDUM WHEEL 54 COMB. M VITRIFIED
FIG. 276. GRINDING A TAPER COLLET.
Set automatic feed to feed at both ends of stroke and to
grind to .002" large, then use pinch feed to finish.
Place stub mandrel C, C'in taper hole of collet A, mount on
centers.
Set swivel table to grind taper. To obtain correct taper,
take light cuts, try taper in gage or spindle hole and adjust
table until taper fits. Use " artists' " blue for marking in
hole.
PROBLEMS IN CYLINDRICAL GRINDING.
221
432. To grind a phosphor bronze taper bushing, A, Fig.
277.
Bushing blank, phosphor bronze. Rough turned to enter
taper hole within f " of small end.
Corundum grinding wheel (plain), 12" X J", No. 54, Grade M,
vitrified.
Speed of wheel 7000 F.P.M. Speed of work 75 F.P.M.
Feed, % width of wheel.
True wheel and centers.
UNIVERSAL GRINDING MACHINE
CORUNDUM
WHEEL
54 M
VITRIFIED
FIG. 277. GRINDING A BRONZE TAPER BUSHING.
Set automatic feed to feed .001" at both ends of stroke and
to grind .002" large, then use pinch feed to finish.
Place bushing A on a built-up taper mandrel B and mount
on dead centers.
Set swivel table to grind taper. To obtain correct taper,
take light cuts and test taper in taper hole in frame, and
adjust table until taper fits.
CHAPTER XV.
DRILLING MACHINES. VERTICAL DRILLING MACHINE. TWIST
DRILLS. GRINDING DRILLS. SIZES OF DRILLS. SPEEDS
AND FEEDS OF DRILLS. LAYING OUT AND DRILLING
HOLES. DEEP DRILLING.
DRILLING MACHINES.
433. Drilling machines are divided into two general classes,
vertical and horizontal. See Advanced Machine Work.
Among the first are centering, vertical, multiple spindle,
and plain radial and universal radial drills. Among the
second, centering, multiple spindle, and horizontal drilling and
boring machines.
There are many special machines in both classes, such as
portable drills, drills driven by hand, rope, and belt, flexible
shaft drills, pneumatic drills, and electrically-driven drills.
Speeds. Drilling machines with belt and cone drives usu-
ally give eight speeds four direct and four with back gears.
Machines with speed gear boxes usually have sixteen speeds
eight direct and eight with back gears. See 458.
Feeds. Drilling machines with belt and cone feeds usu-
ally give from three to four feeds; and with gear feed boxes,
from three to six feeds.
VERTICAL DRILLING MACHINE.
434. Vertical drilling machine described, Fig. 278. This
machine, commonly called a drill press, is an indispensable part
of a modern manufacturing equipment, and is used for all ordi-
nary drilling operations. On this type of machine the work
remains stationary while the revolving drill is fed downward
through the work by hand or by power.
222
VERTICAL DRILLING MACHINE.
223
s'-
FIG. 278. VERTICAL DRILLING MACHINE.
224
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF PARTS.
TIGHT AND LOOSE PULLEY DRIVE. CONE HEADSTOCK. BELT FEED.
A and A' Double column.
B Base table for large work,
slotted to hold clamping bolts.
C Drilling table, revolving.
D Arm supporting table
swiveled on column A.
E Headstock.
F and F' Back gears and
lever to throw back gears "in"
or "out."
G Drill spindle.
H Socket for drill.
/ Drill.
K Feed spindle, splined.
L Cone pulley, four steps.
M and M' Tight and loose
pulleys.
N Driving belt.
P Speed belt.
Q Headstock cone pulley.
R Spindle.
S and S' Bevel gear fast
to spindle and bevel gear feather
keyed to drill spindle. The drive is
from N to M through L, P, Q, R,
S, S' to spindle or with back gears
in N, M, L, P } Q, through back
gears to F, R, S, S' to spindle.
T Shipper rod.
U and U' Feed cones, three
steps.
V Feed belt.
W Spur gears.
X Bevel gears.
Y and Y' Worm and worm
gear.
Z Rack. A pinion on spin-
dle of worm gear Y' meshes with
rack.
1. Sleeve, in which spindle G
rotates; its weight and that of
the spindle is counterbalanced
by weight in column attached
to chain shown. It also carries
rack Z. The feed motion is
through U, V, U',W, K, X, Y, Y'
to Z.
2. Lever to move spindle
quickly up or down in head to
lock or unlock clutch throwing in
or out hand and power feed.
3. Head, position adjustable
up or down column.
4. Lever to adjust head.
5. Clamp bolt.
6. Clamp bolt. By unclamp-
ing 5 and 6 the head 3 can be ad-
justed by lever 4.
7. Hand feed wheel. For
hand feed, lock friction clutch by
pressing lever 2 inward, then turn
wheel.
8. Power feed lever. For
power feed, bring drill to work
and lock clutch by lever 2, then
lock clutch in gear X by pressing
lever 8 upwards.
9. Stop, position adjustable.
10 and 10'. Clamp bolts. By
unclamping bolts the table C may
be swung around column A .
11. Clamp bolt; by unclamp-
ing may revolve table about its
center.
12. Elevation handle.
13. Elevation screw.
14. Nut threaded to 13 and
fitted to arm.
To adjust table vertically,
loosen 10 and 10' with handle 12,
turn screw 13 in nut 14.
TWIST DRILLS.
225
TWIST DRILLS.
435. Twist drills are made by milling two helical grooves
of increase twist in a carbon or high-speed steel-drill blank
(a round bar) to form cutting edges, as in Fig. 279, and to
carry away the chips. For Three and Four-Groove Drills,
see 478. For Drills Twisted from a Flat Bar, see 444.
The metal between the grooves is the web, and is thicker
at shank than at point to make the drill stiffer. The cutting
edges are A, B, and C, Fig. 279. A drill has three clearances.
Body and land clearances are given the drill in manufactur-
ing. The body clearance is obtained by turning or grinding
the body slightly smaller at the shank end; and the land
clearance by milling, leaving narrow lands as at DD f and EE'.
IG. 279. GOOD AND BAD TWIST DRILL GRINDING.
When a drill is ground to an angle of 118, as at F, the
cutting edges A and B are straight and correct, but if ground
to any other angle they will be curved and likely to produce
an irregular hole. Some drill manufacturers use an angle
of 126 for the point of the drill instead of 118.
The lip clearance, GG', is obtained by the student in grind-
ing the drill with a twist drill grinder, Fig. 282, or by hand,
Fig. 283.
226
PRINCIPLES OF MACHINE WORK.
D'J.C'
The angle of point C, Fig. 279, is an indication of the clear-
ances and should form an angle from 125 to 135 with lip B.
This gives a lip clearance at G and G' from, 10 to 15, gradu-
ally increasing from periphery to center. Drill H is badly
ground. Having no clearance, as indicated by angle of
point J, it will not cut and may split at the web. Drill K is
also poorly ground. Having too much clearance, as indicated
by angle of point L, it will cut but will dull quickly and may
chatter.
For very hard material, as unannealed carbon steel, a drill
will cut more effectively if given a small lip clearance, and
for soft material, as gray iron castings, it will cut more rap-
idly if given a larger clearance.
Attention. A reamer drill, that is, a drill that is to be
followed by a reamer, should be care-
fully ground, and it is safest to test
it in a trial piece, particularly if the
drill is ground by hand, to see if it
allows sufficient for reaming.
436. The effect of a long and short
lip, Fig. 280. A drill ground with lip
A longer than lip B will cut large, the
drill following in the path
of its point CC', not in the
geometric center line DD'.
When point pricks through,
the drill rights itself and
FIG. 280. DRILL CUT- drills the remainder of the
TING LARGE, BADLY hole to the Q gize ag
GROUND. ,
at E.
437. Thinning the point of a twist drill. As T ^ G j gT DRI ~
a drill is sharpened by grinding, the point be- WITH POINT
comes thicker on account of the increasing thick- THINNED BY
ness of the web and requires greater pressure to GRINDING -
make it cut. To remedy this, grind a groove C, Fig. 281, on
each side with the thin wheel of the grinder C, Fig. 282.
GRINDING DRILLS.
227
GRINDING DRILLS.
438. Machine method of grinding a twist drill, Fig. 282.
FIG. 282. GRINDING TWIST DRILL WITH TWIST-DRILL GRINDER.
SCHEDULE OF PARTS AND OPERATIONS.
A Column carrying wheels.
B Cup-shaped grinding
wheel for grinding lips of drill.
C Thin grinding wheel for
thinning point of drills. See 437.
D Driving belt.
E Speed belt.
F Shipper, operated by the
foot.
G Drill holder, swivels in its
bearing.
H Bearing for drill holder.
228
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF PARTS AND OPERATIONS. Concluded.
I Arm, adjustable.
J Casing for arm.
K Clamp wheel.
L Wheel which carries pin-
ion that engages a rack on under
side of arm /. To move arm / and
drill holder in or out, release
wheel K and revolve wheel L.
M Handle to swing arm
sideways.
N Gage jaws.
To Grind Drill.
Handle to unclamp jaws
to set for desired clearance as at
N', N', 0', P', to allow drill to
just pass through.
P Twist drill.
Q Lip rest ; set drill holder
forward so that rest will just clear
grinding wheel, then swivel in
bearing H and clamp by wheel K.
R and R' V holder. Swing
holder to left and place drill with
lip against lip rest Q and project-
ing slightly beyond it. Hold in
position by hand.
S Footstock. Move it against
end of drill and clamp.
T Feed screw, to regulate
cuts which should be light.
To grind, swing holder to right.
After one lip is ground, turn the
drill over and grind the second
lip, thus making it a counterpart.
U Eccentric sleeve gradu-
ated to obtain more or less clear-
ance for cutting different metals.
V Wheel to clamp sleeve U.
439. To grind a twist drill by hand, Fig. 283. Place drill
A on rest B against grinding wheel C, with its cutting edge
in a horizontal position. Lower the left hand slightly to
FIG. 283. GRINDING TWIST DRILL BY HAND.
GRINDING DRILLS.
229
obtain the lip clearance, then turn drill over and repeat on
second lip.
Twist drills are obtainable
with grinding lines A A' and
BB', Fig. 284, which allow for
proper angle and location of
point. As the lips should be
of equal length and height,
their length may be measured
with a rule as in Fig. 284, and
their height as in Fig. 285.
Any irregularity in the cutting
lips is doubled in action.
A more rapid and accurate FIG. 284. - MEASURING LENGTH
, i f OF THE DRILL LIP.
method of testing the angle of
point and length and clearances of lips is to use a twist
drill grinding gage, as in Fig. 286. Drill A is placed in V
groove B and gage C adjusted cen-
tral with drill point by screw D.
TWIST DRILL
GRINDING
GAGE
BLOCK E
FIG. 285. TESTING CLEAR-
ANCE AND HEIGHT OF CUT-
TING LIPS OF TWIST DRILL.
FIG. 286. TESTING ANGLE OF
DRILL POINT.
Attention. It requires intelligent practice to grind a
twist drill correctly by hand.
230
PRINCIPLES OF MACHINE WORK.
i
STRAIGHT
SHANK
TWIST DRILL
A
CAST IRON
CHIPS
L
440. To use a straight -shank
twist drill, Fig. 287. Clean shank
of chuck and insert in spindle.
Place drill A in chuck B and
clamp by screw C operated with
wrench D, Fig. 288. To remove
chuck from spindle E, drive in
key F lightly.
441. Drilling cast iron with a
twist drill. The cast-iron chips
L and L' will come out of the
hole in large and small fragments
if the drill is properly ground other-
FIG. 287. DRILLING CAST
IRON.
FIG. 288. DRILL CHUCK WRENCH.
wise the chips will be very small
particles or reduced to powder.
Attention. A drill will bore a hole
slightly larger in cast iron than in
steel, wrought iron, brass or copper.
442. To use a taper shank drill,
Fig. 289. See Morse Standard
Tapers, 656, 657. Clean shank
of socket H and insert in spindle 7,
and clean shank of drill G and
insert in socket. To remove drill
G, drive center key in slot lightly.
443. Drilling steel or wrought iron
with a twist drill, Fig. 289. Steel
and wrought iron chips M and M '
DRILLING STEEL.
231
will come out of the hole in long shav-
ings if the drill is properly ground and
lubricated with lard oil otherwise the
chips will break into small fragments.
Attention. The taper shanks of
socket and drill must be clean and
forced to their seats in spindle and
socket with a quick movement of the
hand or lightly driven in with a soft
hammer.
Note. Drills are obtainable with
shanks to fit special machines, as
blacksmiths' drill presses, etc.
444. A twist drill hot-forged and
twisted from a flat bar is shown in
TAPER
SHANK
TWIST DRILL
G
SPINDLE
6
HIGH SPEED
STEEL DRILL
TWISTED FROM
FLAT BAR
GAS ENGINE
CYLINDER
\
FIG. 289. DRILLING STEEL
OR WROUGHT IRON.
FIG. 290. DRILLING HOLE FOR SPARK
PLUG.
232
PRINCIPLES OF MACHINE WORK.
Fig. 290 drilling a hole for a spark plug in a gas-engine cylin-
der. These drills are obtainable to fit both the regular and
special sockets and they are made of high-speed steel, and
are particularly adapted to rough work of cast iron, boiler-
plate work, rail work, or any hard and tough material. Twist
drills regular and special may be used on wood by running
them at a high speed.
445. A flat drill and set screw drill chuck. Flat drill A
B, Fig. 291, is forged from carbon or high-speed steel,
having a diameter that will fit set screw drill chuck C, and
is secured to chuck by set screw D.
Forge it a little large at E, then grind to size and clearance
at F and F'. Form the cutting lips by grinding.
-D
-T-
r7///M/A '
SET SCREW DRILL CHUCK C \
FLAT DRILL A (^ E 1
\Jl
V/////////I ^
FIG. 291. FLAT DRILL AND SET SCREW DRILL CHUCK.
This drill is used for all metals, but cuts much slower than
a twist drill. It can be made very hard and used for drilling
very hard steel that cannot be drilled with a twist drill.
A drill often glazes the surface of hard steel, and will not
/ yi cut unless the surface is roughed up by inden-
/ / 1 tations with a chisel. See Drilling Extra Hard
Steel, 101.
446. To grind a drill for brass or thin sheet
metal. The helical grooves of a twist drill
give the cutting lips acute cutting angles which
are suitable for steel, wrought iron, and cast
iron. To drill brass or thin sheet metal, grind
move the rake > as a t A, Fig. 292, otherwise
BRASS OR tne drill is liable to " dig in," catch and
SHEET METAL, break.
DRILLING BRASS.
233
447. A straight-groove drill, A, Fig. 293, has straight
grooves which make it a safe drill for any of the compositions
AUTOMATIC DRILL DRIFT
BRASS OR
COMPOSITION
FIG. 293. DRILLING BRASS OR COMPOSITION.
of brass or thin sheet metal. It is grooved the same as a
twist drill. The chuck (socket or drill) may be removed by
inserting the automatic key or drift B in the slot with the
right hand and striking it a blow with its weighted handle
operated with the right hand and receiving the chuck with
the left. It acts as a combination drift and hammer. These
drills are obtainable in parts of an inch and also in wire gage
sizes.
448. Drilling brass or composition, Fig. 293. The chips
will come out of the hole in small angular fragments as at C,
if the brass or composition is hard (cast) ; and in long shavings
as at D, if soft (rolled).
234
PRINCIPLES OF MACHINE WORK.
SIZES OF DRILLS.
449. Regular twist drills with straight or taper shanks
are obtainable in binary fractions, mixed numbers, and whole
number sizes from T y to 3", and by special order from 3 T y
to 6", and for further convenience, in various gage sizes for
pinning, doweling, selecting taps, reamer drills, etc. See
450, 451, 452. Left-hand drills are obtainable from T y
to y by i^. Drills are also obtainable in metric sizes.
Attention. Holes up to 3" are usually drilled or drilled
and reamed, holes from 3" to 6" drilled or bored. Holes
above 6" are bored.
Note. In holes larger than two inches it is best to drill a hole
from one-half to two-thirds the required size with a two-groove
drill and finish it with a three or four-groove drill. See 478.
450. Large drills are selected by the sizes stamped on
shanks or they may be measured with calipers. In regular
drills, one-half inch and less, gages and tables of decimal
equivalents are obtainable. See Fig. 294 and Table.
064 32 64 16 64
OPP.O.Q
S V 64 16 64 32
666000O
OOOOOO
FIG. 294. GAGE FOR FRACTIONAL SIZE DRILLS.
TABLE OF GAGE SIZES IN COMMON FRACTIONS AND
DECIMAL EQUIVALENTS.
SIZE.
DECI-
MAL.
SIZE.
DECI-
MAL.
SIZE.
DECI-
MAL.
SIZE.
DECI-
MAL.
SIZE.
DECI-
MAL.
&
.0625
*
.15625
*
.25
tt
.34375
7
.4375
&
.07812
8
.17187
H
.26562
ti
.35937
If
.45312
&
.09375
X
.1875
.28125
.375
4*
.46875
A
.10937
H
.20312
if
.29687
If
.39062
H
.48437
4
.125
.14062
1
.21875
.23437
H
.3125
.32812
i
.40625
.42187
i
.50
SIZES OF DRILLS.
235
451. Letter Drills. For a greater variety of sizes of drills
than those already mentioned, 26 drills are obtainable with a
difference between consecutive sizes of from four thousandths
to fourteen thousandths and designated by letters from A to Z.
TABLE OF LETTER-SIZE DRILLS AND EQUIVALENTS IN
DECIMALS AND COMMON FRACTIONS.
LETTER
SIZES.
DECIMALS
OF AN INCH.
NEAREST
64TH OF
AN INCH.
LETTER
SIZES.
DECIMALS
OF AN INCH.
NEAREST
64TH OF
AN INCH.
A
B
c
.234
.238
242
M
N
O
P
.302
.316
.323
"&"
4i
D
246
O
332
E
F
G
.250
.257
261
i
R
S
T
.339
.348
358
H
ii
jj
266
ii
u
368
I
J
J
.272
.277
281
6
\&
V
W
x
.377
.386
397
i
it
L
M
.290
295
32
ii
Y
z
.404
413
H
452. Small drills are also obtainable in sets designated by
numbers from 1 to 80. These drills have a range of from one
to eight thousandths of an inch between consecutive sizes.
OOOOOOOOOOOO
24 23
ooooooooooooo
J6 J7 53 29 3D 31 32 33 34 35 36 37 38 39 4(J- 41
OOOOOOOOOOOOOOOO
60 59 5 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42
o ooooooooooOOOOOOO
FIG. 295. TWIST DRILL AND STEEL WIRE GAGE.
SIZES BY NUMBERS, 1 TO 60. HALF SIZE.
See Gages, Figs. 295 and 296, Tables of Decimal Equivalents,
and American Screw Company's Machine and Wood Screws,
664.
236
PRINCIPLES OF MACHINE WORK.
TABLE OF SIZES OF TWIST DRILLS AND STEEL WIRE GAGE
IN DECIMALS OF AN INCH, 1 TO 60.
No.
SIZE OF
NUMBER.
No.
SIZE OF
NUMBER.
No.
SIZE OF
NUMBER.
No.
SIZE OF
NUMBER.
1
.2280
16
.1770
31
.1200
46
.0810
2
.2210
17
.1730
32
.1160
47
.0785
3
.2130
18
.1695
33
.1130
48
.0760
4
.2090
19
.1660
34
.1110
49
.0730
5
.2055
20
.1610
35
.1100
50
.0700
6
.2040
21
.1590
36
.1065
51
.0670
7
.2010
22
.1570
37
.1040
52
.0635
8
.1990
23
.1540
38
.1015
53 .0595
9
.1960
24
.1520
39
.0995
54
.0550
10
.1935
25
.1495
40
.0980
55
.0520
11
.1910
26
.1470
41
.0960
56
.0465
12
.1890
27
.1440
42
.0935
57
.0430
13
.1850
28
.1405
43
.0890
58
.0420
14
.1820
29
.1360
44
.0860
59
.0410
15
.1800
30
.1285
45
.0820
60
.0400
FIG. 296. TWIST DRILL AND STEEL WIRE GAGE.
SIZES BY NUMBERS, 61 TO 80. HALF SIZE.
TABLE OF SIZES OF TWIST DRILL AND STEEL WIRE GAGE IN
DECIMALS OF AN INCH, 61 TO 80.
NUM-
DECI-
NUM-
DECI-
NUM-
DECI-
NUM-
DECI-
BER.
MALS.
BER.
MALS.
BER.
MALS.
BER.
MALS.
61
.039
66
.033
71
.026
76
.02
62
.038
67
.032
72
.025
77
.018
63
.037
68
.031
73
.024
78
.016
64
.036
69
.02925
74
.0225
79
.0145
65
.035
70
.028
75
.021
80
.0135
453. There are four classes of drills: body, reamer, tap and
pin or wire drills.
Body drills are used to drill a hole to a nominal diameter as
stamped on the drill, a I" drill for a J" hole.
SPEEDS AND FEEDS OF DRILLS. 237
Reamer drills are used to drill a hole that is to be finished
by reaming and are from T o" to ^" smaller than reamer.
Tap drills are used to drill for tapping and have a diameter
equal to that of the tap at root of thread plus the clearance.
See Tapping and Threading Sizes, 534, and also Tables of Tap
Drills, 538, 569, 570, 573, 574.
Pin or wire drills are used for holes for easy and driving fits
and usually for small work. . See Dowel pins, 559.
In the smaller sizes, select the wire for the pin, then select a
drill one or two sizes smaller or larger, as required, as allowance
for the fit, by means of the wire gages, Figs. 295, 296, or with
micrometer.
In the larger sizes, select drill, then turn and file pin slightly
smaller or larger, then drill as required.
See Fits in Machine Construction, pp. 68-79.
Important. As drills usually cut slightly oversize, it is safest
to drill a trial hole first in a loose piece to test relative sizes of
drill and pin. If the pin is slightly large it may be held in a
speed lathe chuck and filed.
SPEEDS AND FEEDS OF DRILLS.
454. To calculate revolution of drill (R.P.M.) given the
cutting speed and the diameter of drill.
Multiply cutting speed by 12 to reduce to inches, then
divide by diameter of drill multiplied by 3.1416.
Example. The drill is f " in diameter (high-speed steel
drill) and it is desired to drill at 50 F.P.M. H6W many drill
revolutions are necessary?
crj v 1 9
Solution. - * = 254 R.P.M.
455. To calculate cutting feet of drill (F.P.M.) given
diameter of drill and drill revolutions per minute.
Multiply diameter of drill by 3.1416 and by the number of
drill revolutions, then divide by 12 to reduce to feet.
Example. The drill is I" in diameter and makes 254
revolutions per minute. What is the cutting speed?
Solution. - -750 X 3.1416 X 254 _ 5Q p p M _
12
456. Table of carbon-steel drill speeds and feeds, giving
R.P.M. and F.P.M. that speed may be tested with speed in-
dicator, see Elements of Machine Work, or Cut-Meter, 94.
Feed is given in thousandths of an inch per revolution of drill.
238
PRINCIPLES OF MACHINE WORK.
CAST IRON.
MACHINE STEEL OB
WROUGHT IRON.
BRASS.
DlAM.
OF
R.P.M.
R.P.M.
R.P.M.
DlAM.
OF
DRILL
FEED
FEED
FEED
DRILL.
FOR 35
P.R.
FOR 30
P.R.
FOR 70
P.R.
F.P.M.
F.P.M.
F.P.M.
&
2138
.002
1832
.002
4276
.002
&
1070
.002
916
.002
2138
.002
&
712
.002
610
.002
1424
.002
&
535
.004
458
.004
1070
.004
A
427'
.004
366
.004
854
.004
A
356
.004
305
.004
712
.004
i
A
305
.004
261
.004
610
.004
A
*
267
.008
229
.006
534
.008
*
FOR 30
FOR 25
FOR 60
F.P.M.
F.P.M.
[ F.P.M.
t
183
.008
152
.006
366
.008
1
t
134
.008
127
.006
268
.008
*
*
130
.008
108
.006
260
.008
i
i
114
.012
95
.009
228
.012
1
H
90
.012
76
.009
180
.012
H
H
67
.012
63
.009
134
.012
H
FOR 25
FOR 20
FOR 50
F.P.M.
F.P.M.
F.P.M.
if
54
.012
43
.009
108
.012
if
2
47
.016
38
.012
94
016
2
2*
42
.016
33
.012
84
.016
2
2*
38
.016
30
.012
76
.016
2* .
2i
34
.016
27
.012
68
.016
2f
3
32
.016
25
012
64
.016
3
Attention. Carbon steel varies in hardness. When annealed it
is moderately soft and may be drilled at nearly as high a speed as
machine steel, but unannealed it is hard and will require a reduc-
tion to about one-half the speed of machine steel.
Note. If the cutting of the drill and chips indicates that the
metal is soft, the speed and feed may be increased, and vice versa if
the metal is hard. Keep drills sharp. If a drill is run too fast, the
outer ends of cutting lips will dull quickly and wear away, as a high
speed will generate excessive heat and draw the temper at these points
first. If the feed is too coarse, the drill will chip at the cutting edges,
or break, or the drilling machine will stop.
SPEEDS AND FEEDS OF DRILLS.
239
457. Table of high-speed steel drill speeds and feeds, giving
both R.P.M. and F.P.M. in order that speed may be tested
with a speed indicator (see Elements of Machine Work), or
Cut-Meter, 94.
Feed is given in thousandths of an inch per revolution of drill.
CAST IRON.
STEEL AND WROUGHT IRON.
DlAM. OF
DlAM. OF
DRILL.
R.P.M.
R.P.M.
DRILL.
FOR 70
FEED P.R.
FOR 60
FEED P.R.
F.P.M.
F.P.M.
A
4276
.003
3664
.002
ft
i
2138
.003
1832
.002
i
ft
1424
.003
1220
.002
i
107,0
.006
916
.004
^
854
.006
732
.004
ft
$
712
.006
610
.004
610
.009
522
.008
I?
*
534
.009
458
.008
*
FOR 60
FOR 50
F.P.M.
F.P.M.
1
366
.013
304
.012
f
f
268
.013
254
.012
260
.013
216
i
228
.013
190
.012
1
H
180
.018
- 152
.016
H
If
134
.018
126
.016
i*
FOR 50
FOR 40
F.P.M.
F.P.M.
if
108
'.018
86
.016
if
2
94
.027
76
.020
2
2 f
84
.027
66
.020
2i
2*
76
.027
60
.020
2*
2f
68
.027
54
.020
2f
3
64
.027
50
.020
3
Attention. Speed for brass twice the speed for cast iron, and
same feed per revolution.
458. Tables of spindle speeds (R.P.M.) for belt-driven ver-
tical drilling machine and speed lathe. Select the R.P.M.
240
PRINCIPLES OF MACHINE WORK.
from the Tables of Drill Speeds and Feeds, etc., 456 or
457, and place belt on step of cone that gives the nearest
THROUGH CONE
DIRECT
'
63
CD
I ST
STEP
CD
10
112
2"
STEP
18
191
3
STEP
31
340
<D 4
STEP
55
THR
OUQH BACK
GEARS
m
FIG. 297. TABLE OF SPINDLE SPEEDS FOR 24-lNCH
VERTICAL DRILLING MACHINE.
PI
225
0>
1 ST
STEP
368
2
STEP
620
3 D
STEP
1160
04
STEP
'
FIG. 298. TABLE OF SPINDLE SPEED FOR H-!NCH SPEED LATHE.
R.P.M. obtainable with machine as given in Tables, Figs.
297 and 298.
459. Hand and power feeds. Vertical drilling machines
with belt feed usually have three feeds varying, with the dif-
ferent machines, from .002" to .005" for a fine feed, or from
SPEEDS AND FEEDS OF DRILLS.
241
.007" to .010" for a medium feed, and from .015" to .120" for
a coarse feed, per revolution.
Belt spindle driven machines, with gear feed boxes, give a
range of feeds from .004" to .039" per revolution of spindle.
Use feed per revolution of spindle that is nearest to that given
in Tables of Drills, Speeds and Feeds, 456, 457.
Speed lathes and most of the small vertical and horizontal
drilling machines have hand feed only, obtainable by a hand
wheel or a lever. After grinding a large drill, it is good prac-
tice before applying the power feed to start it by hand to
see if it is cutting correctly as determined by the chips pro-
duced. Very small drills should be started and may be fed
by hand to avoid breaking.
460. Table of spindle speeds for a standard high-speed drill-
ing machine which gives the positions of the levers in the
speed gear box for 16 speeds at 70 F.P.M. for drilling or
boring holes from J" to 7" in diameter.
Hole . . .
y
1*
t*
1*
Without
Revolutions
Hole
534
I"
428
11*
356
1A"
306
11"
backgear.
With lower
267
214
178
153
backgear
Hole
2*
2%"
3*
3i"
"With upper
134
107
89
76
backgear
Hole
4"
5"
6"
7"
With both
Revolutions
67
53
45
38
backgears.
461. Table of gear feeds for a high-speed drilling machine
obtained from gear feed box in thousandths of an inch per
revolution of spindle.
.006"
.009"
.013"
.018"
.027"
.039"
242
PRINCIPLES OF MACHINE WORK.
LAYING OUT AND DRILLING HOLES.
462. To drill, ream, tap, and counterbore large or medium-
size work, use a vertical drilling machine and clamp work to
table or hold it by the aid of a vise, angle plate, jig, or fix-
ture, in order that the setting of the work may not be dis-
turbed during operations, for if disturbed the accuracy may
be lost, and in many cases the work spoiled. Very large work
may be clamped to the base table of the machine. Very often
it is more convenient to drill small work in a speed lathe.
See 489^91.
463. To set spring dividers, A, Fig. 299, to an accurate
dimension, place lower point in a line on rule B, as at C, and
move upper point by nut D to coincide with line E. At
A f , B' is shown how rule is tilted so that dividers may be set
accurately.
B-
FIG. 299. SETTING DIVIDERS TO A STEEL RULE.
464. To use dividers to describe a circle, Fig. 300. Set
dividers F to size, place block G in vise H and indent with
light center-punch mark at desired location. Then place
point K in mark, incline dividers slightly in direction of
revolution and describe circle with point L.
LAYING OUT AND DRILLING HOLES.
243
FIG. 300. DESCRIBING CIRCLE WITH DIVIDERS.
465. Rough drilling. Determine location of hole in work
by the eye, then make a heavy center-punch mark in which
to start point of drill.
466. Approximate drilling. Use dividers or surface gage
to locate the hole, then make heavy center-punch mark in
which to start drill. Drill hole without drawing the drill.
467. Accurate drilling, laying out work, Fig. 301.
FIG. 301. LAYING OUT WORK FOR ACCURATE DRILLING.
244
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS.
1. Brighten surface of block
and coat with copper sulphate.
See Elements of Machine Work.
2. Draw center line BC and
intersecting line PDF lightly
with surface gage, and center
punch at point of intersection D.
3. Describe circle E diameter
of drill and make four or more
light center-punch marks at F.
4. Enlarge center-punch mark
D to guide drill in starting.
Attention. For large holes, additional circles may be de-
scribed inside of size circle to deter-
mine accuracy of cut before it reaches
the size circle.
468. Inspection circle. Work that
is laid out by one person and drilled
by another should have an inspection
circle, as at A, Fig. 302, outside the
size circle B. This is an inspection
check on both the laying out and the
drilling.
469. Drawing the drill, Fig. 303.
SOCKET
H
FIG. 302. WORK LAID
OUT WITH AN INSPEC-
TION CIRCLE.
DRILLING TABLE
FIG. 303. CUTTING A GROOVE WITH CENTER CHISEL
TO DRAW THE DRILL.
LAYING OUT AND DRILLING HOLES.
SCHEDULE OF OPERATIONS.
245
1. Insert drill G in socket H.
Swing table / until drill will pass
through any convenient hole in
table. Clamp and clean table.
FIG. 304. GROOVE TO DRAW
THE DRILL.
2. Place block A on table and
bring drill down into center punch
hole. Clamp with JJ' and KK'.
3. Start drill and feed by hand
to cut a little ; if not cutting con-
centrically as at L, Fig. 304, raise
drill and "draw" hole with center
chisel M, Fig. 303, by cutting
groove N, Fig. 304.
For a small amount, cut as at
N', Fig. 305.
FIG. 305. GROOVE TO DRAW A
DRILL A SMALL AMOUNT.
4. Start drill again, using hand-
feed; if not cutting centrally, re-
peat 3.
5. Stop drill, loosen work and
bring drill down into clean conical
hole, reclamp, and finish hole with
power feed.
Attention. A drill cannot be " drawn " after it has cut
to its full diameter.
In starting a thick-pointed drill, particularly if a light pres-
FIG. 306. IRREGULAR CAVITY CUT
BY DRILL.
sure is used, it may cut an irregular cavity, as at A, Fig. 306,
which may be drawn as at B in the same manner as a true
cavity.
246
PRINCIPLES OF MACHINE WORK.
470. Accurate drilling, reaming, and tapping holes I, II,
III, Fig. 307.
:
.1
STOCK- CAST-IRON
FIG. 307. SCHEDULE DRAWING OP ACCURATE DRILLING,
REAMING, AND TAPPING.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Material, cast iron, planed and free from visible defects; weight, 2 Ib,
Oil bearings of drilling machine with machine oil.
Set hole in table in alinement with drill.
Use carbon-steel drills.
For High-speed Drills, see 457.
Time, 50 min.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Prepare surface for marking
(1). See Elements of Machine
Work.
Draw line (2), intersect at (3),
(4), (5), center punch inter-
sections.
Important. Describe circles
exact diameter of drills (f , f ,
f), center punch four inter-
sections on circles.
Enlarge centers, (3), (4), (5).
Vise.
Copper jaws, 8" or
10" hand smooth
file, copper sul-
phate.
Leveling plate , surface
gage or dividers,
rule, automatic
center punch.
(Magnifying glass
optional.)
Dividers, rule, auto-
matic center punch.
Hammer, center
punch.
LAYING OUT AND DRILLING HOLES.
TO DRILL HOLE NO. I.
247
Insert drill in spindle and
clamp block.
Start drill in center, (3).
Draw drill if necessary.
Loosen clamp, center block
(see 469), reclamp and
drill hole.
Vertical drilling ma-
chine.
2d or 3d speed, or 170
R.P.M. Hand feed.
" taper shank, twist
drill, wrench,
clamps, bolts and
nuts.
Hammer, center
chisel.
Wrench.
2d or 3d speed, or 170
R.P.M. Power feed.
TO DRILL AND REAM HOLE NO. II.
Drill same as hole No. I, (4).
Replace drill by a center.
Ream hole (see 290), (6).
Vertical drilling ma-
chine.
" drill, I" reamer
drill.
Conical center.
f" hand reamer,
reamer wrench.
TO DRILL AND TAP BOTTOM HOLE NO. III.
Drill same as hole No. I ($"
depth), (5).
Place block in bench vise and
tap hole (see 529 and Fig.
347).
First, use taper tap.
Second, use plug tap.
Third, use bottoming tap.
Vertical drilling ma-
chine. 2d or 3d
speed, or 225 R.P.M.
Vise.
f" drill, depth gage.
Copper jaws, f " X 10
United States
Standard plug tap,
tap wrench, lard
oil.
1" X 10 United States
Standard plug tap.
I" X 10 United States
Standard bottom-
ing tap.
471. To drill for set screws. Locate and drill with a tap
drill, then tap the hole. See Set Screws, 563.
248
PRINCIPLES OF MACHINE WORK.
472. Allowance or limit for bolt holes. For rough work,
locate and drill holes with a drill -fa" or more, large, to give
the bolts body clearances as at A, Fig. 308.
On fine work the holes are drilled with a body drill, or
drilled with a reamer drill and reamed, and the bolts fitted
to the holes.
MACHINE BOLT
FIG. 308. CLEARANCE OF BOLT AND WORK.
473. Allowance or limit for cap screws or stud bolts. For
rough work drill a hole in cap with a drill T ^o" or more, large,
for body clearance, as at A, Fig. 309, and a body drill for
fine work, then drill hole in frame or bottom part of work
with a tap drill and tap, as at B.
CAP
SCREW
FIG. 309. USING A CAP AS AN IMPROVISED JIG.
474. To drill in alinement for cap screws without jig.
Three methods.
First Method. Locate and drill a body hole in cap, then
put cap in place and use it as a templet to mark circle A,
LAYING OUT AND DRILLING HOLES.
249
FIG. 310. LOCATING
CENTER OP TAP HOLE.
Fig. 310. Make four center-punch marks B, and with divid-
ers locate center of circle and make center-punch mark C.
With C as center, describe circle D,
diameter of tap drill. See Accurate
Drilling, 467-471.
Second Method. Locate and drill
the body hole in cap, clamp it to
bottom part and use it as a jig. Run
body drill down hole in cap and make
it cut its full diameter in base only.
Then remove and use the tap drill
to drill the tap hole. When bolting
a cap to a shaft bearing or pillow
block in which two or more cap screws are used, it is best to
drill and tap one hole and use a cap screw, C, Fig. 309, to
secure the cap to the shaft bearing while drilling the other
holes, D and E, Fig. 309.
Attention. If the work has a large number of cap screws
or studs, as a steam-chest cover or cylinder head, and no jig
is provided, a tap drill bushing may be used in the body hole
in cap to guide the tap drill accurately. See Jigs, 495-504.
Third Method. Clamp
cap to pillow block, or
clamp any two pieces to-
gether, locate and drill
both parts with tap drill,
then take cap or top part
off and enlarge its hole to
body size of screw with a
counterbore whose head
diameter is the same as
the body of the screw,
and with a guide the di-
FIG. 311. MARKERS OR PUNCHES FOR ame ter of tap drill. See
LAYING OUT DUPLICATE WORK. Co unterboring ; 575.
475. Markers for laying out duplicate work, Fig. 311.
Plates to be drilled may be laid out rapidly by using one
BODY TAP
CENTER CIRCLE CIRCLE
MARKER MARKER MARKER
250 PRINCIPLES OF MACHINE WORK.
as a templet, as the cap, Fig. 311, then using a marker, as
at A. Other styles of marker are shown at C, E, and G.
476. To drill work held by hand or in a vise on drilling
table, Fig. 312. Long work is often held on drilling table
by hand, or a bolt may be inserted in a hole in the table to
prevent work revolving with the drill. Small square or flat
pieces may be held by a monkey wrench, see Fig. 315. A
safer and more accurate method is to hold work in a vise as
in Fig. 312. Clean table, jaws, and base of vise. Clamp
vise A to table B by two bolts, one of which is shown at C,
to hold block D to be drilled with drill E held in chuck F.
c
DRILLING TABLE B
FIG. 312. DRILLING WORK HELD IN VISE. VERTICAL DRILLING
MACHINE.
Place work against fixed jaws and bring the sliding jaw up
by handle. Rap the work lightly with a lead hammer to
bed it properly, during and after closing of vise.
477. To drill work held against an angle plate. See 278,
Fig. 313. Bolt angle plate A to table B by bolts, as at C.
Clamp bracket D to vertical face of angle plate by straps and
bolts E and E'. Drill and ream hole through part F parallel
to base. Jack screw G supports work.
478. Three and four-groove twist drills for drilling cored
holes or to follow a two-groove twist drill. Four-groove twist
drill H, Fig. 313, is used to drill or enlarge cored hole in
LAYING OUT AND DRILLING HOLES.
bracket casting D. These drills are usually made
and are followed by a standard shell reamer.
251
/' small
ANGLE
Pi-ATE
FIG. 313. DRILLING A CORED HOLE IN WORK
CLAMPED TO ANGLE PLATE.
479. To drill diametrically through a shaft, Fig. 314.
Secure shaft A on drilling table B in V-groove blocks C and
FIG. 314. DRILLING A SHAFT IN V BLOCKS.
VERTICAL DRILLING MACHINE.
C' by clamps and bolts D and D'. Lay out shaft E in the
usual way, and set central as follows: Place try square upon
252
PRINCIPLES OF MACHINE WORK.
table with the edge of the blade against shaft, first at one
side, then at the other, measuring distance from the blade to
the center mark and adjusting. Then move table until the
point of drill will enter center- punch mark, clamp and drill
hole.
480. Automatic drill chuck and collet, Fig. 315.
SPINDLE
DRILLING TABLE
FIG. 315. CHANGING DRILLS WITHOUT STOPPING MACHINE
BY USING AN AUTOMATIC CHUCK AND COLLET.
SCHEDULE OF PARTS AND OPERATIONS.
A Automatic drill chuck
taper shank, fits spindle.
B Drill press spindle.
C Taper shank drill, fits
taper hole in collet.
D Collet, straight shank.
E Groove.
F Locking ring. Raise it,
insert collet, then drop it, which
will lock two pins in chuck A into
groove E. To remove collet,
raise ring and it will drop out.
LAYING OUT AND DRILLING HOLES. 253
SCHEDULE OF PARTS AND OPERATIONS. Concluded.
G Spherical end of collet
which prevents it from slipping
through hand.
H Collet made with straight
end for use with small drills.
/ Block ; requires two holes
drilled.
J Wrench to hold block.
K Bolt, inserted to prevent
wrench from revolving.
L Drill for first hole.
M First hole drilled, after
which drill is removed without
stopping machine.
N Second hole to be drilled.
Drill C inserted as shown, with-
out stopping machine.
The collet is driven by its
tang and held in place by the
locking pins.
481. Cutting metal plates by drilling.
A metal plate may be cut apart, if the
cut is straight, by planing, milling, or
shearing; but if the cut is curved, as in
Fig. 316, drill holes A, B, C, etc., about H
diameters apart, and sever walls D, E, F,
etc., with chisel.
FIG. 316. CUTTING
482. Slotting by drilling, plugging, and A METAL PLATE
drilling. The slot is laid out on both BY DRILLING AND
sides, Fig. 317. As a hole that cuts into
another cannot be drilled, drill holes
A and B, then plug and drill holes
C, D and E to cut away the walls.
Drive out plugs
and finish slot
by filing, slotting,
or milling. As
FIG. 317. SLOTTING BY
DRILLING, PLUGGING,
AND DRILLING.
a time saver for large lots, a jig may be
made.
483. Lead holes for large drills, Fig.
318. To make the large drill A cut faster,
first drill " lead " hole B (diameter of drill
same as thickness of point or larger)
LEAD HOLE
through work C. Draw drill with center FlG . 3 18. LEAD HOLE
chisel as at D, Fig. 319. FOR A LARGE DRILL. .
254
PRINCIPLES OF MACHINE WORK.
484. To start drill when the surface is slanting, Fig. 320.
First chip or mill surface perpendicular to the drill, as shown
at A. Use chalk or copper sulphate on this surface. Center
and lay out with dividers, then drill in the regular way.
LEAD
HOLE
FIG. 319. DRAWING A
DRILL WHERE A LEAD
HOLE is USED.
FIG. 320. DRILLING HOLE ON
SLANTING SURFACE.
FIG. 321. DRILLING A POR-
TION OF A HOLE IN A PIECE.
485. To drill a part of a hole in the side of a block as at A,
Fig. 321. Clamp to the piece to be drilled another block, as
at B, by clamps as at C, C r . Center and lay out in regular
way. The drilling may be done on drilling table of vertical
drilling machine, as shown, or at the speed lathe.
486. A boiler tube hole cutter, A, Fig. 322. For large
holes in plate work, special drill A, with a pin guide B to fit
punched hole in boiler head C is used. It has two cutting lips
which cut a circular groove and removes ring of metal.
DRILLING IN THE SPEED LATHE. "
255
FIG. 322. DRILLING OR CUTTING HOLES IN BOILER HEAD.
487. Drill extension, Fig. 323. Make hole A (diameter of
the drill) in the end of a steel rod of suitable length. File
slot B across bottom of the drilled hole as at C. File flat D
on the shank of drill. Taper the bottom of slot B slightly so
that drill will hold firmly in hole A. The end of drill should
not abut against side E.
FIG. 323. EXTENSION FOR DRILL.
Leveling work on drilling table. For rough work,
use spirit level. For accurate work, test with a piece of bent
wire with an offset and held in chuck. Rotate spindle slowly
to swing wire around to test level.
489. To drill small flat or square work in speed lathe, Fig.
324. Place drill A in chuck B, which is attached to live
spindle by means of an arbor. Hold work C against table
center D by hand vise E, and support on Tee rest. When
point of drill breaks through, hold work firmly against table
256
PRINCIPLES OF MACHINE WORK.
center, as there is a tendency for the work to draw away and
break the drill.
FIG. 324. DRILLING FLAT WORK IN SPEED LATHE.
490. To drill a hole into or through a shaft at right angles
to its axis. Place shaft A, Fig. 325, in V center B, and
drill C in socket D, then start drill carefully to make hole
central. When hole is to go through work, line out on both
sides, drill half-way through from each side, using regular
pointed center against work.
FIG. 325. DRILLING SHAFT HELD IN V CENTER IN SPEED LATHE.
DEEP DRILLING.
257
491. To drill a hole in the end of a shaft parallel to axis,
Fig. 326. Place shaft A against dead center B and drill by
FIG. 326. DRILLING HOLE IN END OF SHAFT IN
SPEED LATHE.
drill C in chuck D. To drill a hole clear through center of
shaft, drill half from each end. See Chucking Work with
Steady Rest, Advanced Machine Work.
DEEP DRILLING.
492. Oil drills for deep drilling, as at A, Fig. 327, provide
channels for conveying the oil directly to the point of the
drill to keep it cool. These drills are obtainable in sizes
from y to 2" diameter, with both straight and taper shanks.
For chucking, these drills are fitted with a hose-pipe con-
nection which is threaded to the side of the drill.
For rapid drilling, oil is used at a pressure of from 400 Ibs.
to 600 Ibs. to the square inch, not only to lubricate the drill
but also to force out the chips.
Attention. For drilling or chucking in cast iron with these
drills, compressed air may be used both to cool the drill and
to force the chips out of the drilled hole.
258
PRINCIPLES OF MACHINE WORK.
493. To drill a deep hole with taper shank oil drill, Fig.
327.
FIG. 327. DRILLING STEEL FORGING WITH OIL DRILL.
DRILLING MACHINE.
VERTICAL
SCHEDULE OF PARTS AND OPERATIONS.
A Oil drill.
B, B' Oil holes through solid
metal to point of drill.
C Oil supply pipe.
D Stationary collar.
E Oil socket; oil passes
through C, hole in E to holes B, B'
in drill.
F Steel forging to be drilled.
G Flat vise holding forging F.
H Vise base.
K Fixed jaw.
L Sliding jaw.
M Screw bearing against
jawL.
N Square end of screw for
wrench to tighten jaws.
P Drilling table.
Q and Q' (Q' not shown)
Bolts holding base of vise to table.
DEEP DRILLING.
259
494. Hollow drills for spindles, tubes, and gun barrels,
Fig. 328.
FIG. 328. DEEP DRILLING WITH HOLLOW OIL DRILL. ENGINE LATHE.
SCHEDULE OF PARTS AND OPERATIONS.
A Work to be drilled.
B Chuck.
C Steady rest.
D Threaded end of hollow
drill screwed into oil tube. Drill
shown in detail in Fig. 329.
E Steel oil tube ; oil follows
along tube and grooves of drill to
the point.
F Fixture in which hollow
drill is clamped.
G Carriage on which fixture
F is mounted.
H Oil pipe.
K Stuffing box, to prevent
oil flowing backward. Oil and
chips are forced out through hol-
low shank of drill D.
FIG. 329. HOLLOW OIL DRILL FOR DEEP DRILLING.
Attention. To start drill accurately, drill hole in end of
work with a regular drill of the same diameter and to a depth
equal to the diameter.
Note. These drills are obtainable from f " to 3". Deep
holes above 3" in diameter are drilled or bored with a cutter
attached to a boring head which is a running fit in the starting
hole. See Advanced Machine Work.
CHAPTER XVI.
DRILLING JIGS, AND MULTIPLE-SPINDLE DRILLING MACHINES.
RADIAL DRILLING MACHINES. TAPS AND DIES.
DRILLING JIGS, AND MULTIPLE-SPINDLE DRILLING
MACHINES.
495. The demand for machinery with interchangeable parts
has compelled builders to design and use drilling jigs, milling
jigs, planing jigs, gages, and templets to produce standard
and duplicate parts accurately and economically. See Jig
Making, Advanced Machine Work.
496. Drilling jigs are fixtures carefully made with hardened
bushings to guide drills, reamers, etc., so that their operation
shall be the same on each piece. They may be divided into
about five classes, and each class is best adapted to some par-
ticular kind of work.
1. Plate jigs are used for flanges, machine frames, etc.
See 498, 499.
2. Solid jigs are used for work that can be readily clamped
to jig body. These jigs are preferred by some for general
work. See 509.
3. Box jigs are used for general work. The work is placed
in a box, the hinged cover closed and fastened and the work
held in place by binding screws. See 502, 504.
4. Rotary jigs are for work where the jig is too heavy to
be easily turned over at the drilling machine. The jig con-
sists of a box mounted on trunnions to facilitate revolution.
5. Multiple jigs are for work that is to be index-drilled. The
bushings are placed in a turret head.
497. An improvised jig or templet, Fig. 330. To drill and
ream bolt holes B, C, and D, equidistant, in two or more
flanges: First, lay out, drill, and ream one flange carefully.
Next, clamp one drilled flange to another in the way they are
260
DRILLING JIGS.
261
FIG. 330. COUPLING FLANGE.
to fit, and insert a plug or mandrel through centers A to
aline them. Drill and ream holes in the other flange. Other
methods are to drill both flanges then ream together, or drill
and ream in pairs.
498. Plate (flange) drilling jig, Fig. 331, is a cast-iron disk
E supplied with a plug FG to aline flange and jig, a hardened
FIG. 331. FLANGE DRILLING JIG. (PLATE JIG.)
steel drill bushing H and reamer bushing J. Plug T is for
alining drill and jig and plug W to prevent relative movement
of flange and jig.
262
PRINCIPLES OF MACHINE WORK.
499. To use flange jig, Fig. 332. Place flange K on parallel
pieces L and M, with jig N on top of flange; clamp lightly by
strap P, block Q, and bolt R to table S. Aline jig and
drill spindle with plug T, Fig. 331, moving work by rapping
with a soft hammer until the plug will enter bushing exactly
central; clamp firmly. Drill hole with reamer drill U. Substi-
FIG. 332. DRILLING AND REAMING WITH FLANGE JIG.
tute reamer bushing J f for drilling bushing H', and ream with
fluted reamer V. Place plug W, Fig. 331, in first hole to keep
jig and flange in alinement as at W, Fig. 332, while drilling
and reaming second and third holes. Reverse jig to drill the
second flange.
600. Drilling and tapping engine cylinder heads. When
two pieces of work are to be clamped together with cap screws
or stud bolts, as a cylinder and cylinder head, two removable
bushings are required for the jig; the first with body drill
holes for the head, the second with tap drill holes for the
cylinder. To tap the holes by hand, a tap bushing is some-
times used to guide the tap. See Automatic Tapping Attach-
ment, Fig. 335.
501. Multiple-spindle drilling machines are used to save time
in changing drills, reamers, and counterbores, in moving work
DRILLING JIGS.
263
from one machine to another, as is necessary with a one-spin-
dle drilling machine. One spindle holds a tap drill, another a
body drill, another a counterbore, etc., all running, and the work
is moved along the table from one spindle to another without
stopping the machine. See Figs. 333 and 337.
502. Box jigs are used to further increase the rapidity and
accuracy of drilling, reaming, tapping, and counterboring.
The work is locked in a box provided with accurately
machined bearings to rest on the drilling table. The jigs are
made heavy and are held in position by their own weight, thus
saving the time that would be consumed in clamping and
alining.
503. To drill and ream bolt holes in coupling flange with a
box jig and a two-spindle high-speed drilling machine, Fig. 333.
H
FLANGE
A
BOX JIG
FIG. 333. DRILLING AND REAMING HOLES IN COUPLING FLANGE
WITH Box JIG.
264
PRINCIPLES OF MACHINE WORK.
||* High-speed steel drill,
600 R.P.M.
Time, 6 min.
SCHEDULE OF OPERATIONS.
f
High-speed steel reamer,
400 R.P.M.
1. Place box jig A on table.
Insert drill B and reamer C, C' in
spindles.
Locate heads D and E on col-
umn and clamp stops F and G on
spindles to limit travel of drill and
reamer as tested by passing drill
and reamer through bushing into
empty jig, or test drill and reamer
by lines placed on outside of jig
which indicate position of bush-
ings.
Place flange H in jig with hub
up, and secure with button J and
screw K. Start machine by ship-
per L.
2. With left hand move jig
to aline drill bushings with drill.
Use lever feed M and drill three
holes.
3. Turn jig over as shown,
dotted, at A'.
4. Ream the holes, using lever
feed N. P shows position of
flange as it is reamed, and Q shows
two flanges bolted together.
Attention. Stop G must check
reamer before it strikes drill bush-
ing or reamer and bushing will
be spoiled.
Note. Before placing jig on table, and before turning
jig over, brush off table.
To prevent abrasion of bushings, drill, and reamer, apply a
little oil with finger to upper part of drill and reamer.
504. Box jig for pieces to be drilled, reamed, and tapped
in different directions, Fig. 334.
SCHEDULE OF PARTS.
A Box jig for pieces to be
drilled, reamed, and tapped in
different directions.
B Duplicate of work held in
jig 4-
C Cover held in place by
thumb nut D.
E and E' Two of the binding
screws for adjusting work in jig.
F Table.
G Hole in piece B that is
being drilled in the duplicate.
H Drilling bushing.
K Reaming bushing put in
position after drilling.
L Drill sV small to allow
for reaming.
RADIAL DRILLING MACHINES
VERTICAL DRILLING MACHINE
265
FIG. 334. A Box JIG FOR DRILLING, REAMING, AND TAPPING IN
DIFFERENT DIRECTIONS.
RADIAL DRILLING MACHINES.
505. Radial drilling machines, commonly called radial drills,
differ from vertical drilling machines in that the drill is
moved to aline with the work, which is more convenient for
large work, such as machine frames, that cannot be moved
easily.
A plain radial drilling machine can be used only for vertical
drilling, while a universal radial drilling machine may be used
not only for vertical drilling but may be adjusted, also, to
drill at almost any angle and used with hand or power feed.
266
PRINCIPLES OF MACHINE WORK.
506. Plain radial drilling machine, Fig. 335.
RADIAL ARM
t
FIG. 335. DRILLING, AUTOMATIC TAPPING, AND STUD SETTING.
SCHEDULE OF PARTS.
A Radial arm ; may be
swung around column by hand,
and raised up or down by power.
B Column.
C Spindle head; may be
moved back and forth on arm A.
D Spindle ; may be moved up
and down in head C by hand.
E Levers for quick move-
ment of spindle D.
F Hand wheel for slow
movement of spindle.
G Knob operating clutch
throwing " in " or " out " power
feed.
H Drilling table for light work.
K Base table for heavy work.
RADIAL DRILLING MACHINES. 267
507. Automatic tapping attachment. Friction drive. 1, Fig.
335, is shown fitted to the spindle of a radial drilling machine
for drilling, tapping, and setting studs in an engine cylinder
2, without stopping or reversing the drill spindle. Socket 3
holding tap drill 4 is used to drill the hole, and is followed by
tap 5 in tap socket 6, which in turn is replaced by stud socket
7 that sets stud 8 in place. Shell 9 holds reversing mechanism
and is kept from revolving by rod 10 resting against rod 11.
The attachment holds drill sockets and will drill holes in the
regular way. To tap, press spindle D downward by hand lever
E until the tap reaches the bottom of the hole as indicated
by the slip of the friction drive, then raise handle E, which
throws in the reversing mechanism and backs out the tap.
After setting stud 8, raise handle E to back off holder 13,
leaving stud 8 in cylinder 2. See Attention, 549.
With some stud holders, stud 8 is released by rapping pin 12
lightly with a hammer before reversing the holder; on others,
the release of stud is obtained by a stud nut which operates
on the principle that the coarser threads of the holder, when
reversed, will release the finer threads of the stud. The cyl-
inder is clamped to base table K at 14. For R.P.M. see Power
Tapping, 533.
Attention. The studs may be set to project to any uniform
height by using a gage block between stud holder and cylinder.
Note. Cap screws, nuts, and slotted screws may be set in
like manner by using special wrenches and screw drivers.
508. Jig vise. In the absence of a regular jig, duplicate
work of certain classes maybe done with the aid of a jig vise
as in Fig. 336. To use this vise lay out and drill one piece
and use it as a gage by which to set the stop and jig plate.
Vise A is heavy and rests without' clamping on table B of
drilling machine C. Work D is set against adjusting stop E
and clamped by setting up sliding jaw F with lever G. Jig
plate H carrying removable bushing K is then adjusted to
the desired position for the hole and clamped to fixed jaw
of vise. A radial drilling machine being used, spindle L and
268
PRINCIPLES OF MACHINE WORK.
drill M may be moved to suit the position of work. Cylin-
drical distance gage N, cut to its center, is sometimes used to
set the center of the hole in the jig a given distance from the
fixed jaw.
PLAIN
|& RADIAL
DRILLING
MACHINE
c
i
FIG. 336. DRILLING WITH JIG VISE.
609. To drill and counterbore duplicate parts. In Fig. 337,
a multiple-spindle drilling machine is arranged to drill and spot
face casting, as A, A' held by jig B. Insert drill C in spindle D
and drill a hole until arrested by stop E. A smaller drill in
spindle F finishes the hole as shown in section at F'. The
jig is turned over and drill G used to drill the holes in lugs
H and H f through bushings K and K'. Counterbore L is
fitted to spindle M for spot facing lugs H and H f for the
screw or bolt heads. Fixture N of the jig is used to clamp the
rod of the .other half of the strap while it is being drilled.
TAPS AND DIES.
269
MULTIPLE
SPINDLE
DRILLING
MACHINE
FIG. 337. DRILLING AND COUNTERBORING DUPLICATE PARTS.
TAPS AND DIES.
510. A tap cuts inside threads. Taps are obtainable in all
standard sizes, right or left, either United States Standard or
Sharp V threads, and are designed for use by hand or power.
29, Ratchet, and Square threads are cut with special taps.
511. Sizes of taps. Taps are obtainable from \" diameter
to 3". See table of U. S. S. and Sharp V-Thread Screws, Taps,
etc., 538. Small taps and screws less than \" in diameter
are obtainable from T y to fa" by 64ths in Sharp V threads
only. See 574, and Machine Screws, 569-573.
512. Set of hand taps, Fig. 338. Taper tap A is turned off
at end D to root of thread, to enter the drilled hole and also
270
PRINCIPLES OF MACHINE WORK.
-F
FIG. 338. SET OF HAND TAPS.
to cut the thread gradually. For tap drills, see 538, 569,
570, 573, 574. Plug tap B is tapered a little at end E.
Bottoming tap C is not tapered at F.
Shank G of all ordinary taps is made
the same diameter or smaller than root of
thread. For " jig " tapping, the shank is
made to full diameter of thread. Threaded
parts H are the " lands " or teeth. Flutes
or grooves K form a cutting edge for face
of the thread and an outlet for chips. The
diameter and threads per inch and name of
thread are stamped on each, as " J X 10,
U. S. S." Fig. 339 is a section of a right tap, the land at
H' and the flute at K'.
FIG. 339. SECTION
OF RIGHT TAP.
TAPS AND DIES.
271
513. Clearance on taps. The first two or three threads
are given clearance or " backed off." On large taps the sides
of the teeth are "backed off" by special machines, or by
hand with a file.
514. Nut taps are made with long shanks and long threaded
parts, and in some cases the thread is cut taper on the end
for about half the length of the threaded portion, so that
cutting will be gradual.
^ITX. 515. Pulley taps are long so that
the wrench may rotate when tapping
hub of pulley, whether tap passes
through rim of pulley or by its edge.
516. Hob or master taps, Fig. 340,
are for tapping solid bolt dies, ad-
justable dies, screw plates, etc. Taper
&" to I" per foot.
517. An adjustable hand tap, Fig.
341, is split and adjusted by taper
screws A and A', and the two parts
locked by screws B and B f . Such a
tap is used to enlarge threaded holes.
518. Automatic taps are used in
turret lathes, screw machines, etc., by
power. When desired length of thread
is cut the tap is closed by hand or
automatically, and withdrawn, avoid-
ing reversal of work. See Elements of
Machine Work and Advanced Machine FIG. 340.
Work. HOB OR
MASTER TAP.
519. Taps are sharpened by grind-
ing the front of the teeth radial with a grinding wheel whose
edge has been rounded over with a diamond tool. They
may be hand or machine ground.
520. Tap (reamer) wrenches. See Fig. 344. In the adjust-
able tap wrench the jaws are tightened on the tap, so that
FIG. 341.
ADJUSTABLE
TAP.
272
PRINCIPLES OF MACHINE WORK.
there will be no loosening of the grip during the operation of
tapping.
521. Adjustable Tee tap wrench for small taps, Fig. 342.
A carries chuck B adjusted on tap C, and is shown tapping
nut D held in vise E.
ADJUSTABLE T
TAP WRENCH
A ""
FIG. 343. SINGLE-END TAP WRENCH.
FIG. 342. TAPPING WING NUT.
522. Single-end tap wrench, Fig. 343. To tap a hole in a
corner the tap is steadied with the left hand and rotated with
the right by means of a
single-end tap wrench
or a ratchet wrench.
A ratchet wrench is
usually operated with
one hand, thus lessening the liability of breaking the tap.
523. Tap holes are either drilled in solid stock, punched,
cored and drilled, or cored and bored. As a screw or bolt
should enter a tapped hole in the frame of a machine about 1
times its diameter, the hole is drilled to a depth of twice the
diameter of the screw and then tapped to a depth of about 1J
times its diameter.
TAPS AND DIES.
273
Attention. Do not start a tap in a cored hole, as the
surface is hard, and covered with sand and scale. This method
would dull the tap.
524. Loose nuts. See Alinement Tapping, 626, 627.
Less than I" are threaded in a vise with a tap. Large nuts
are threaded in a lathe, or rough threaded in a lathe and
finished with a tap. See 594.
Nuts that are to be finished are tapped as accurately as can
be determined by the eye. Then they are squared at a right
angle to the axis of the thread. See Nut Mandrels, 256.
525. Hand tapping a rough nut, Fig. 344. The holes in
machine steel or wrought iron, hexagonal and square cold-
pressed nut blanks, usually come punched the correct diameter
for tapping.
FIG. 344. TAPPING HEXAGONAL NUT BLANK. APPROXIMATE TAPPING.
SCHEDULE OF OPERATIONS.
1. Place nut A level in vise B
and drop lard oil on threads of
right tap C.
2. Place wrench D on tap and
hold tap perpendicular to face of
nut. Rotate wrench D to right, at
same time pressing hard, down-
ward, until thread catches or it
may ream hole.
3. Sight tap in front and at
side ; if it is out of true, correct by
turning tap backward, then for-
ward, exerting correcting side
pressure on forward stroke only.
4. Oil tap freely. After each
forward stroke, back tap part of a
turn to allow chips to drop out
and oil to reach teeth.
274
PRINCIPLES OF MACHINE WORK.
Attention. Press evenly on both handles and make tap
cut true while first few threads are being cut. To make cor-
rection after threads are firmly caught may break the tap.
A tap that is difficult to start may be started dry, then oiled.
Small taps, J" and less diameter, spring considerably before
they break. When a tap begins to spring, back it out, clean,
and oil.
526. Accurate hand tapping. Three methods. Figs. 345,
346, 347.-
Holes in pillow blocks, frames of machines, etc., must be
tapped in alinement to the machined surface or the bolts,
cap screws, stud bolts, etc., will bind and may prevent
them from being bolted in place. The most accurate tap-
ping is done in a drilling machine before work is undamped,
Fig. 345.
If more expedient to remove work from drill press before
tapping, a tapping jig may be used as shown in Fig. 346. In
the absence of a tapping jig, a hole may be accurately tapped
by testing with a square, as shown in Fig. 347.
SCHEDULES OF OPERATIONS, MACHINES AND TOOLS.
527. Tapping in vertical drilling machine, Fig. 345.
FIG. 345. HAND TAPPING IN VERTICAL DRILLING MACHINE
ACCURATE TAPPING.
TAPS AND DIES.
275
1. Clamp block A to table B by
clamps C and C". Clamp table.
Drill hole to desired diameter.
2. Remove drill and insert
center D on spindle. Place
wrench E on tap F, insert in
hole and bring center D down
into countersink in end of tap.
3. Tap in regular way, keeping
tap central by following it with
center D.
528. Jig tapping, Fig. 346.
b.u
- X
JIG
TAP
B
SCREV
CLAM
G
t^- f< ^
HAND
TAPPING
JIG
C
5- B * 1
\ WORK
/
|
>A/ x -^
WORK
B
BEAM
D
VISE
C
FIG. 346. TAPPING WITH JIG.
ACCURATE TAPPING.
FIG. 347. TESTING TAP WITH
TRY SQUARE . ACCURATE TAPPING.
1. Aline work A and jig C
by plug D having a diameter at
E the same as that of the tap and
at F the same as that of the hole
in the work.
2. Fasten A and C together
with clamp G, remove plug and tap
in regular way with jig tap B.
Attention. The hole in jig is
the full diameter of tap.
529. Testing tap with try square, Fig. 347.
1. Insert right taper tap A in
hole in work B held in vise C;
rotate to right and press down-
ward hard until thread catches.
2. Remove wrench and test
alinement of tap with square
by placing beam D on work and
blade E against shank of tap.
The nature of light line between
blade and shank of tap will
indicate correction to be made.
Test with square at two posi-
tions at 90 to each other.
3. If tap is not in alinement,
correct as in 525.
Attention. Test with square
frequently during operation of
starting tap.
276
PRINCIPLES OF MACHINE WORK.
530. Tapping "through" holes and "bottom" holes.
To tap a " through " hole, as a nut, use a taper tap. To
tap a "bottom" hole, use three taps: first, the taper tap;
second, the plug tap; third, the bottoming tap. When the
nature of the work will admit, drill the hole deeper than the
length of screw to avoid using a bottoming tap.
631. To make a tap cut large. In the absence of a larger
tap, or an adjustable tap, roll cotton waste as at A, Fig. 348,
and insert it into grooves of tap B, then run the tap through
nut C held in vise D. If necessary, repeat with more waste
or a narrow strip of sheet copper or brass.
FIG. 348. MAKING A TAP CUT LARGE.
532. Removing broken taps. The skillful use of a center
punch or chisel and hammer will sometimes remove a broken
tap. If the work is small, it may be annealed and drilled out.
Fig. 349 shows a mechanical method of removing a broken
tap. Box A held in vise B shows a broken tap C. Four
fingers of tap remover D, two of which are shown at E and E f ,
are pushed down into grooves of tap by collar F. Sleeve G
is then pressed down close to work and tap removed by
rotating tap wrench H.
TAPS AND DIES. 277
FIG. 349. REMOVING A BROKEN TAP.
533. Power tapping. Taps are used by .power in drilling
machines, boring machines, turret lathes, and nut-tapping
machines. See 506, 507, also Advanced Machine Work.
Taps may be used safely at from one-third to one-half the
R.P.M. of drills (see 454-457) for holes not deeper than 1
times diameter of tap. For deeper holes the speed must be less.
534. Tapping and threading sizes. To avoid breaking the
tap or tapping a full thread, which is not desirable, especially
on cast iron, the tap drill or bore of hole in lathe work should
be larger than the theoretical root diameter of tap. To avoid a
full thread on a screw threaded in an engine lathe or a full and
torn thread when cut with a die, the screw blank should be
smaller than the nominal diameter of screw.
The amount that the tap drill should be large or screw blank
small varies for different classes of work and with different
users, but in general it is for United States Standard thread
from .004" for a \" thread to .010" for a 3" thread; and for a
Sharp V thread, from .010" for a J" thread to .060" for a 3"
thread.
Attention. When United States Standard thread taps,
which are used to tap the nuts, are made to a larger diameter
at the top of the thread to allow for clearance, it is unneces-
sary to tutn the screw blank small.
278 PRINCIPLES OF MACHINE WORK.
535. Diameter of a tap drill, A, Fig. 350, equals the diam-
eter at root of thread, as at B, for United States Standard
and Sharp V-thread taps plus the allowances
given in 534. The approximate method
of finding this is to measure the root
diameter of the tap with thin, pointed
calipers (see 216), but the more accu-
rate method is by calculation.
536. To calculate root diameter for Sharp
V thread.
FIG. 350. RELA- Constant: 1.732 = double depth of a 1"
TION OF DRILL TO P Sharp V thread.
TAPPED HOLE.
Formula :
1 732
Outside diam. of tap ~ -r -. r = diam. of tap
No. threads per inch
drill.
Example. Find diameter of drill for f " tap, 10 Sharp V
threads per inch.
1 700
Solution. .750 - ^^ = .5768.
Use f f " tap drill. See 33 and Table, 538.
537. To calculate root diameter for United States Standard
thread.
Constant: 1.299 = double depth of a I" P United States
Standard thread.
Formula:
1 299
Outside diam. of tap - = -r - = diam. of drill.
No. threads per inch
Example. Find diameter of drill for J*' tap, 20 United
States Standard threads per inch.
1 2QQ
Solution. .250- ~~ = .185, diameter of drill.
Use fV" tap drill.
TAPS AND DIES.
279
638. Table of United States Standard and Sharp V-thread
screws, taps, and tap drill sizes which are also the sizes to
bore holes for inside threads.
DIAMETER
OF
TAP.
No. OF THREADS PER INCH.
SIZES OF TAP DRILLS.
u. s. s.
SHARP V.
U. S. S.
SHARP V.
i
20
20
ft or 11
&orl4
ft
18
18
MorC
Mori
1
16
16
HorN
iforL
ft
14
14
fforS
If orR
|
12
25
2
i
13
13
M
IforX
%
14
ii
ft
12
12
ti
32
H
I
11
11
H
i
H
11
11
11 1^
ft
1
10
10
I
1!
$
10
10
H
H
1
9
9
11
II
it
9
9
ti
If
i
8
8
H
If
H
7
7
H
H
li
7
7
i*
i&
if
6
6
HI
ii
if
6
6
iH
r?
if
5J
5
in
iH
if
5
5
ij
iff
it
5
*i
H
iff
2
4*
4i
if!
iff
2*
4*
4*
ill
iff
l
4
4
ift
2J
2f
4
4
2^
2|
3
i
3|
?tt
2A
Attention. For screws and taps smaller than \", see 565-
574.
539. A die cuts outside threads on screws, bolts, rods, etc.,
usually with one cut by hand or power, and this size is desig-
nated by the diameter of the screw it will cut. Right or left,
United States Standard, Sharp V, 29, and Ratchet threads
280 PRINCIPLES OF MACHINE WORK.
can be cut with dies, but Square threads cannot be successfully
cut by them.
Dies are made by drilling and tapping die blank with taper
hob or master tap (see 516) from the back to give it body
clearance.
The flutes are made by drilling and filing, or milling to pro-
duce radial cutting edges for general work. Negative cutting
edges are used for brass. The muzzle or cutter side is
tapered or chamfered to enable die to start centrally and cut
thread gradually.
540. Sizes of dies. Solid and separate dies are obtainable
in all standard sizes in United States Standard or Sharp V
threads to match taps. See Table, 538.
541. Automatic dies are used in turret lathes, screw ma-
chines, and bolt cutters operating by power. They are made in
sections and held in die head so that when desired length of
thread is cut die is opened by hand, or automatically, and
withdrawn, avoiding reversal of work.
542. Solid dies are sometimes sharpened by grinding with
a small grinding wheel. See Advanced Machine Work.
Dies made in halves are sharpened with a thin wheel, and
chasers, of which automatic dies are composed, are ground
separately with an ordinary wheel.
543. Power (die) threading. Dies are used by power in
drilling machines, screw machines, turret lathes, and bolt
cutters. They are run at a cutting speed of one-third that
of drills, see 454-457, or from 10 to 20 F.P.M. This speed
may be increased if material is very soft, as screw machine
stock, and abundant lubricant is used.
Attention. Carelessly threading with a die or without a
lubricant at too high a speed, as 75 or 100 F.P.M., would injure
a die so badly that it could not be used at a higher speed than
6 or 8 F.P.M. until sharpened or replaced by a new one.
Slow speed and an abundant supply of lubricant keep the
die cool, which is necessary for accurate work and the pres-
ervation of the die.
TAPS AND DIES
281
644. Hand (die) threading. To thread bolt by hand with
die and die stock. Fig. 351.
FIG. 351. THREADING BOLT OR ROD BY HAND.
SCHEDULE OF OPERATIONS.
Place die A in stock B and hold
bolt C in vise D. Die is shown
in detail at E, F. Top side E
has full thread to surface and is
stamped " f X 10, U. S. S."
Place die muzzle side down in
stock and gently fasten by set
screw (z, entering cavity H. Put
guide bushing K in bottom of
stock and fasten by thumb
screw L. File an even bevel on
end of bolt to start die. Oil end
of bolt through top of die and
force die onto bolt with downward
pressure and rotation of handles
to the right until die cuts a few
threads, after which it will not
need downward pressure but will
feed itself. Oil, and occasionally
rotate backward to allow chips
to drop out and oil to reach cut-
ting edges. To terminate thread
abruptly, turn die and stock over
and use side E. Die is spring-
tempered at M, and adjusted by
taper screw at N, N'. Some
dies have taper phi adjustment
and in place of bushing have ad-
justable jaws to guide die.
Attention. Dies are often
used to size screws that have been
rough threaded in the lathe, as
they finish work nicely, produce
uniform sizes, and save time.
CHAPTER XVII.
BOLTS AND NUTS. CAP AND SET SCREWS. MACHINE SCREWS.
COUNTERBORING AND COUNTERSINKING. CALCULAT-
ING DIAMETER OF BLANK TO MILL SQUARE OR
HEXAGONAL. INDEXING IN ENGINE LATHE.
BOLTS AND NUTS.
545. A bolt, Fig. 352, is a rod of metal with a head at one
end and a thread and nut at the other. It is used to fasten
together two or more pieces of any material. Bolts are
FIG. 352. CLAMPING WITH BOLT.
made of steel, iron, and bronze. See Table of United States
Standard Bolt Heads and Nuts, 644, 645.
The length of the bolt is measured from under the head
to the point, therefore a bolt will clamp its length minus
the thickness of the nut. Bolts under 20 inches are usually
threaded about 2 times their diameter; over 20 inches, about 3
times.
While the most common forms of heads are square or
hexagonal, as in Fig. 353, bolts with various styles of heads
are obtainable, as eye bolts, bolts with skew heads, eccen-
282
BOLTS AND NUTS.
283
trie heads, key heads, etc. Bolts may be obtained with brass,
copper and bronze heads electrically welded to steel bodies,
and are largely used in electrical and government work. See
Cap Screws 557.
There are three classes of bolts:
First, rough bolts which are forged and threaded without
machining.
Second, semi-finished bolts with body and under-head and
nut machined.
Third, finished bolts which are machined all over.
They are obtainable rough forged and machined, or ma-
chined from bar stock.
1
SQUARE HEAD.
HEXAGONAL HEAD.
PLANER HEAD.
IMPROVISED BOLT. STUD BOLT.
FIG. 353. DIFFERENT KINDS OF BOLTS.
284
PRINCIPLES OF MACHINE WORK.
FIG. 354. USING STUD
BOLT AS A FASTENING.
546. Planer bolts, Fig. 353-3, have thin and flat hexagonal,
or square heads to fit Tee slots, and are used to bolt work to
planer and other machine tables. A
rough iron washer is generally used un-
der the nut. Thin nuts are obtainable.
547. An improvised bolt, Fig. 353-4,
often called a double-end bolt, may be
made quickly by threading both ends
of a rod and using two nuts.
548. Stud bolts, Fig. 354, have one
end threaded to screw hard into work
B and the other to receive nut C to
fasten head D to cylinder. As the
corners of nuts and bolt heads scar
finished work, the sides are often
squared down to the flats as at E.
549. Setting studs. Studs may be set in place by hand or
power. See 506, 507. To set studs by hand use a stud
holder, Fig. 355, which
consists of block A,
screw B, and lock
nut C. Stud D is
screwed into the cyl-
inder head by hand.
Holder A is screwed
on stud D any desired
distance, and screw B
is set against stud D
and locked with nut
C; then a wrench is
used on the holder to
set the stud. The
height of the studs
in the cylinder head
should be uniform and is determined by the distance stud D
is screwed in holder A, and height of gage block F.
Attention. Always clean and oil a screw before screwing it
in nut or work. See 593.
FIG. 355. SETTING STUD BOLT IN CYLINDER
HEAD WITH STUD HOLDER.
BOLTS AND NUTS.
285
550. Expansion bolt A, Fig. 356. An expansion bolt
is used to bolt a machine, plank, or bracket, as at B, to brick
or stone walls where it is not desirable to drill holes entirely
FIG. 356. USING EXPANSION BOLT
AS A FASTENING.
through. As nut C is tightened the tapered head A' forces
expanding bushing D against walls of hole. See Lag Screws,
560.
551. Headless bolts may be secured in holes in a stone
foundation by scarring, running in hot lead, and calking.
Sulphur or type metal is sometimes used and not calked.
552. A nut, Fig. 357, is a block of metal which may be of
any shape with a threaded hole to receive the threaded end
of a bolt, rod, or screw. While the
most common forms of nuts are square
or hexagonal, either cold punched or
hot pressed, special nuts of various
styles are obtainable, as collar nuts
which have to be operated with pin or
spanner wrench, and regular and cap
or blind nuts combined with the washer
for special work, etc.
553. Lock or check nuts, Fig. 357. FIG. 357. LOCK NUT TO
When nut as at A and bolts as at B PREVENT LOOSENING OF
, . , . , . REGULAR NUT.
are subjected to much jarring and m
danger of becoming loose, a second nut which may be thinner
as at C, and called a " lock" or " check" nut, is first put on
and screwed to bind hard on the work or cap D, and held with
286
PRINCIPLES OF MACHINE WORK.
a wrench while the regular nut A is screwed down hard against
it. If a loose connection is desired on the cap or other work,
the regular nut A is held with a wrench and lock nut C backed
hard against it.
554. Spring cotter or split pin. A method used to prevent
the nut from becoming lost is to insert a spring cotter into
a hole bored through the end of the stud or bolt above or in
back of the nut. The ends of the cotter are spread apart,
which prevents it from dropping out.
555. A castle (automobile) nut, Fig. 358, is a still safer
method. Bolt A protrudes through the nut B which is pro-
vided with diametrical slots. Spring
cotter C passes through a slot and
through a hole in the bolt, and its
points are spread as at D. Spring
keys similar to the split pin C, made
of flat steel, are much used. See
642, 643.
A spring cotter alone prevents
an ordinary nut from backing off,
and if used with a castle nut pre-
vents the nut from moving either way. .
556. Turnbuckles are used to connect and regulate the
length or tension of truss rods, titf rods, pipes, or wires. They
are either machined from hexagonal stock as at A in Fig.
SPLIT
PIN
FIG. 358. CASTLE NUT TO
PREVENT UNFASTENING.
C
FIG. 359. A TURNBUCKLE TO CONNECT AND REGULATE
TENSION OF TRUSS RODS AND TIE RODS.
359, or forged and turned and supplied with right and left
threads or with a right thread on one end and a swivel on
the other. Lock nuts are sometimes used as shown.
CAP AND SET SCREWS.
287
CAP AND SET SCREWS.
557. Cap screws are used to fasten one piece of metal not
threaded to another that is threaded, as in Fig. 360. They
CAP
SCREW
FIG. 360. CLAMPING WITH CAP SCREW.
differ from a bolt in that they are not supplied with a nut.
See 473. They are made in steel, iron, or brass, with differ-
ently shaped heads such as square, hexagonal, round, flat,
etc., Fig. 361. Cap screws with brass, copper, and bronze
heads electrically welded to steel bodies are also obtainable.
See Bolts, 545.
Cap screws range in diameters from J" to It", United
States Standard and Sharp V threads. See Table of Tap
Drills, 538.
The length of square, hexagonal, round, and fillister head
cap screws is measured from under head to point. Flat
and oval countersunk heads are measured over all. These
have an included angle from 72 to 82. See Machine Screws,
565.
There is no universal standard of heads, but different
screw manufacturers have standards of their own which
differ from one another. See Counterboring, 575, and
Countersinking, 579.
To avoid special wrenches, cap screws with heads the same
size as United States Standard bolt heads and nuts are
obtainable. See 644.
288
PRINCIPLES OF MACHINE WORK.
Square Head.
Hexagonal Head.
Hexagonal Head
Tap Bolt.
[T
Oval FilUster Head. Flat Fillister Head.
Collar Screw.
7 8
Round Head. Countersunk Head.
Oval Countersunk
Head.
10
Fillister
Head Stud.
FIG. 361. DIFFERENT KINDS OF CAP SCREWS.
Short screws are usually threaded to the head. Long
screws are threaded about two-thirds the length of the body.
558. Tap bolt, Fig. 361. A cap screw threaded to the
head to clamp a thin piece of work to a thick one.
CAP AND SET SCREWS.
289
659. Dowel pins to insure alinement in erecting machin-
ery. These pins are especially useful where machines have to
be taken apart and re-erected, as they preserve alinement
independent of the cap screws or bolts.
gosfil
- -I '-
DOWE1
PIN
BED
c
BRACKET
A
SHAFT B
FIG. 362. USE OF DOWEL PINS.
Bracket A, Fig. 362, forming a bearing for shaft B, is
fastened to bed C by screws D and E. To always insure
alinement of the bearing after once adjusted, use at least
two pins as at F, F' and G, G'. They are usually made a
driving fit in one part and an easy fit in the other part. On
some classes of large work taper dowel pins are used to fit
taper holes.
560. Lag screws, A, Fig. 363, are used to fasten machines
to the floor or light hangers, as B to hanger plank C. Bore
holes for lag screws slightly larger than the root diameter of
the screw. Lubricate the screw with soap, tallow, or oil,
290
PRINCIPLES OF MACHINE WORK.
start by driving slightly. Split tapering sleeves "of malleable
iron with projections to grip the walls of the hole, and with
inside threads to fit lag screws, are obtainable, and are used
as expansion bolts. See Expansion Bolts, 550.
LAG SCREW
FIG. 363. FASTENING A HANGER
WITH A LAG SCREW.
661. Hanger bolts, for fastening large hangers and pillow
blocks, are threaded as a lag screw at one end and as a bolt
at the other to receive a nut, and are operated with a pipe
wrench, or by locking two nuts together on the threaded por-
tions and using a monkey wrench.
662. Wood screws are obtainable in diameters from Nos. to
30 by the American Screw Company's gage, Fig. 372, and
in length from J" to -6". The length, except round heads, is
measured over all, and the threaded portion is about three-
fifths of the length. Round heads are measured under the
head but come a little short. For example, 1" and under will
come about T y short, and over an inch about J" short. There
is no standard number of threads per inch. Flat and oval
countersunk heads have an included angle from 72 to 82.
See Countersink, 579. These screws are designated thus :
\y X 10, flat head, bright.
14" X 9, round " , blued.
I" X 6, flat " , brass, etc.
CAP AND SET SCREWS.
291
WOOD SCREW
A
Wood screws are often used to fasten metal to a wooden
backing, Fig. 364. Flat-head screw A fastens wrought-iron
bar B to wood C. A body hole is drilled through metal B
and countersunk. As a wood screw makes its own nut, it is
often permissible to force a small screw
into soft wood without boring a hole;
still, for a large screw, or hard wood,
or nice work, a hole should be bored to
nearly the size of the root diameter of
the screw, and the screw lubricated.
For rough work and soft wood a reg-
ular screw is often driven from one-
half to two-thirds its length with a
hammer, then turned to its seat with a
screw driver. A special drive wood
screw is obtainable which may be
driven its entire length with a hammer.
It is removed with a screw driver.
FIG. 364. USING WOOD
SCREW AS A FASTENING.
Wood screws are supplied with lead nuts and are often used
as expansion bolts in marble or slate. See Expansion Bolt, 550.
To fasten metal fixtures to slate or marble, wood screws and
litharge are also used. A body hole is drilled in the slate or
marble, which is filled with litharge mixed with boiled linseed
oil or glycerine and the screw is forced into this preparation.
1
Round Point.
2 3
Headless Cup Headless Cone
Point. Point.
FIG. 365. SET SCREWS.
Hanger Pivot
Point.
563. Set screws, Fig. 365, are used to fasten pulleys to
shafts and for other work of similar nature. See 317, also
292 PRINCIPLES OF MACHINE WORK.
Advanced Machine Work. Set screws are obtainable case-
hardened, of steel or iron, in diameters from \" to 1 J", United
States Standard and Sharp V' threads. Length of screw is
measured from under head to point. Headless screws are
measured over all.
564. Thumb screws and wing nut, Fig. 366. Thumb
screws and wing nuts are obtainable in steel, iron, and brass,
1
Flat-head 2 3
Thumb Screw. Nurled Head. Wing Thumb Nut.
FIG. 366. THUMB SCREWS AND WING NUT.
and range in diameter from J" to 1" in regular sizes and from
to 30 in machine screw sizes. See 565. Length of screw
is measured from under the head to the point.
MACHINE SCREWS.
565. Numbered screws, called machine screws, and desig-
nated thus: 10 X 30, meaning 10 size and 30 threads per inch,
are used to obtain a greater variety of sizes in screws less
than one-half inch in diameter instead of those measured
in binary fractions as &" X 30. See 574. There are two
standards: The American Society of Mechanical Engineers'
Standard Machine Screw (see 569), which has the United
States Standard form of thread, and the American Screw
Company's Machine Screw (see 573), which has the Sharp
V form of thread. The numbers range from to 30, with
standard and special number of threads per inch. See Gage,
Fig. 372.
MACHINE SCREWS.
293
They are used in general manufacturing, experimental
work, and in building apparatus. The screws are obtain-
Countersunk
Head.
Oval Fillister
Head.
Flat Fillister
Head.
Oval Counter-
sunk Head.
FIG. 367. MACHINE SCREWS.
able in steel and iron either bright or blued, and in brass, as
in Fig. 367.
The sizes of the screw heads of both standards are nearly
the same. The length of the screw is measured the same as
are cap screws, and the length of the threaded
portions and the angle of the countersink heads
are also the same. See Cap Screws, 557. See
Wood Screws, 562. For Counterboring, see
575. For Countersinking, see 579. To use a
machine screw as a bolt a hexagonal or square J?IG. 353.
nut is obtainable, and applied as in Fig. 368. MACHINE
SCREW BOLT.
566. Machine screw taps are obtainable in
standard and special numbered sizes the same as machine
<e
FIG. 369. MACHINE SCREW PLUG TAP.
screws. A plug tap, as in Fig. 369, is the most used. Taper
or bottoming taps are seldom needed. The taps may be
used to tap work held in a chuck in a speed lathe, 338, or
the tapping may be started in the lathe and finished at the
294 PRINCIPLES OF MACHINE WORK.
vise. Fig. 370 shows method of tapping a hole in a collar for
a machine screw.
FIG. 370. TAPPING A COLLAR WITH A 10 X 30 MACHINE-
SCREW TAP.
Warning. As the smaller sizes of these taps break very easily,
use a tap drill large enough to allow for three-quarters or seven-
eighths of a full thread only, and apply an even and delicate
pressure on the tap-wrench handle. Rotate tap gently forward
and backward and when the muscle sense indicates that the
tap is springing, rotate it backward to prevent breaking. See
522-525.
567. Machine screw dies are obtainable in standard and
special numbered sizes, the same as machine screws, and usu-
ally round and adjustable as at A, Fig. 371. By means of
the taper pin B or a taper screw, the die may be made to cut
slightly large or small to obtain a desired fit of screw in nut.
The die is held in the die stock by means of a set screw, see
544.
While regular machine screws are obtainable, it is often
desirable to make screws with special heads or of special
lengths as at C and C", Fig. 371. Rod D may be held in a
universal chuck E (or in one of the spring (draw in) chucks as
at F) in the hollow spindle universal hand lathe, and turned
MACHINE SCREWS.
295
to desired size and chamfered. Die and die stock G are held
against table center H with muzzle or chamfered end of die
on screw blank and die stock supported by Tee rest /. The
belt K is pulled with left hand to rotate screw blank, and
MACHINE SCREW
DIE
A
FIG. 371. THREADING A SCREW WITH 10x30 MACHINE-SCREW DIB
IN UNIVERSAL HAND LATHE.
die is forced onto screw blank with lever L operated with
right hand.
Attention. Machine-screw die stocks have no guide, and
while a short thread may be cut in a vise with the die without
noticeable defect, a long thread would be crooked and not
desirable for many purposes.
The thread should be cut in the lathe as in Fig. 371, or
started in the lathe and finished in the vise.
568. American Society of Mechanical Engineers' standard
machine screws, see 569, 570, have United States Stand-
ard form of thread. The difference between consecutive
sizes, as to 10, is .013"; and between alternate sizes, as 10
to 30, is .026".
In order that the screws shall always fit the tapped holes,
296
PRINCIPLES OF MACHINE WORK.
the taps are slightly larger than the screws, and each is made
to maximum and minimum sizes, but the difference between
minimum tap and maximum screw is sufficient for error in
pitch and wear of tap, insures a good fit and makes the screws
interchangeable.
569. Table of American Society of Mechanical Engineers'
standard machine screws, taps, and tap drill sizes.
NO. AND
THREADS
PER INCH
OF SCREW
OR TAP.
MAXIMUM
SCREW
DIAMETER.
MAXIMUM
TAP
DIAMETER.
NEAREST
DIAMETER
IN 64THS.
BODY
DRILL.
TAP
DRILL.
0X80
.060
.0632
A
52
56
1X72
.073
.0765
&
&
53
2X64
.086
.0898
ft
42
50
3X56
.099
.1033
^
37
47
4X48
.112
.1168
i
31
43
5X44
6X40
.125
.138
.1301
,1435
4
29
27
39
35
7X36
.151
.1569
&
21
31
8X36
.164
.1699
U
H
29
9X32
10X30
.177
.190
.1835
.1968
S
13
8
28
24
12X28
.216
.2232
1
17
14X24
.242
.2500
i
i
10
16X22
.268
.2765
A
J
3
18X2O
.294
.3031
fk
JL
A
20X20
.320
.3291
ft
Q
G
22X18
.346
.3559
54
U
K
24X16
26X16
.372
.398
.3828
.4088
A
w
z
if
P
28X14
.424
.4359
A
A
R
30X14
.450
.4619
If
5
U
Attention. The body drills given in tables are the nearest com-
mercial drills larger than maximum tap sizes to provide an easy fit.
The sizes of the tap drills given are larger than the root diameters of
threads for clearance.
Drills designated by parts of an inch are according to Table given
in 450 and Fig. 294. Drills designated by letters are according to
the Table of Letter Size Drills, see 451, and those designated by
numbers are according to the Twist Drill and 'Steel Wire Gage and
MACHINE SCREWS.
297
Table, given in 452 and Fig. 295. In the absence of these tables
the sizes of the body drills required may be obtained by measuring
the outside diameter of the tap, and the sizes of tap drills required
may be obtained by measuring the root diameter of the tap and allow-
ing a little for clearance.
570. Table of American Society of Mechanical Engineers'
special machine screws, taps, and tap drill sizes.
NO. AND
THREADS
PER INCH
OP SCREW
OR TAP.
MAXIMUM
SCREW
DIAMETER.
MAXIMUM
TAP
DIAMETER.
NEAREST
DIAMETER
IN 64THS.
BODY
DRILL.
TAP
DRILL.
1X64
.073
.0768
ft
ft
54
2X56
.086
.0903
A
42
51
3X48
.099
.1038
&
37
48
4X40
.112
.1175
31
45
4X36
.112
.1179
31
46
5X40
.125
.1305
29
40
5X36
.125
.1309
29
42
6X36
.138
.1439
A
27
36
6X32
.138
.1445
&
27
38
7X32
.151
.1575
21
32
7X30
.151
.1578
ifa
21
33
8X32
.164
.1705
H
H
30
8X30
.164
.1708
H
H
30
9X30
.177
.1838
A
13
28
9X24
.177
.1850
ft
13
30
10X32
.190
.1965
H
8
23
10X24
.190
.1980
8
28
12X24
.216
.2240
3*2
1
19
14X20
.242
.2511
J
i
14
16X20
.268
.2771
7&
J
4
18X18
.294
.3039
&
A
1
20X18
.320
.3299
H
Q
F
22X16
.346
.3568
1!
U
I
24X18
.372
.3819
w
fc
26X14
.398
.4099
M
z
o
28X16
.424
.4348
T^
A
s
30X16
.450
.4608
II
8
V
571. American Screw Company's machine screws. These
screws and taps to correspond are numbered from to 30
and have the Sharp V form of thread. The difference be-
tween consecutive sizes is .01316".
298
PRINCIPLES OF MACHINE WORK.
FIG. 372. AMERICAN SCREW
COMPANY'S
AND WIRE GAGE
572. American Screw Company's
machine screw and wire gage, Fig.
372, is graduated on one side as
shown, on the other as the English
wire gage, from 17 to 0000 on the
right; and as the American wire
gage, 15 to 0000 on the left of the
slot. The diameter of screw A is
10, shown at B. For diameter in
inches, see Tables 573, 664.
The notch in side of gage facili-
tates measuring length of screws,
as C.
Attention. For practical uses
this gage may be utilized also to
measure machine screws of the
A. S. M. E. Standard, see Tables
569,570.
573. American Screw Company's
SCREW machine screws and taps, also body
and tap drill sizes.
NO. AND
THREADS PER
INCH OF SCREW
OR TAP.
MAXIMUM
SCREW AND
TAP DIAMETER.
NEAREST
DIAMETER
IN 64THS.
BODY
DRILL.
TAP DRILL.
2X56
.08416
t
42
48
4X36
.11048
"
31
41
6X32
.13680
$$"
27
33
8X32
.16312
K
18
28
10X24
.18944
9
23
12X24
.21576
$i"
1
15
14X20
.24208
15 H
10
16X18
.26840
11"
J
5
18X18
.29472
*r
N
1
20X16
.32104
Q
E
22X16
.34736
11 //
3*2
T
K
24X16
.37368
P
1
N
26X16
.40000
P
28X14
.42632
f I"
"A
R
30X14
.45264
ti"
1!
U
Attention. This table gives the most used sizes of screws and
taps from to 30.
COUNTERBORING AND COUNTERSINKING.
299
574. Table of Sharp V-thread taps, 5 V' and smaller, in binary
fractions with tap drill in numbered sizes (twist drill and wire
gage).
SIZES AND THREADS
PER INCH OF
TAPS.
TAP
DRILL.
SIZES AND THREADS
PER INCH OF
TAPS.
TAP
DRILL.
1^X60
IN
[o. 55
&X28
K
o. 26
ftxeo
' 52
AX30
23
&X48
' 47
&X32
23
&X56
' 46
11X24
21
T&X60
' 46
HX28
20
&X32
' 45
HX32
20
&X36
' 44
^X22
19
&X40
' 43
T&X24
18
&X44
' 43
^X28
17
&X48
' 42
^X30
15
iX32
1 40
^X32
13
iX36
' 38
MX22
10
iX40
' 37
MX24
10
i X44
' 36
MX28
9
&X30
' 35
MX32
9
&X32
3.2
iX20
7
&X36
' 35
iX22
5
&X40
' 33
iX24
2
^X30
' 31
1X32
2
&X32
' 30
UX18
4
&X36
' 29
iJX20
2
&X40
' 29
11X24
3
HX32
' 30
||X82
1
HX36
' 29
Axis
2
HX40
' 28
^X20
<
' 1
1^X24
' 27
AX24
' 1
Attention. These taps are obtainable commercially, but the
screw must be " home made " or obtained by special order.
COUNTERBORING AND COUNTERSINKING.
575. A counterbore, Fig. 373, is a tool used to make a
concentric cylindrical enlargement at the end of a hole to
Fia. 373. COUNTERBORE FOR FACING SEAT FOR BOLT HEAD OR SCREW,
300
PRINCIPLES OF MACHINE WORK.
receive a bolt head or screw head as in Fig. 374, and to pro-
vide an accurate seat, and the process is called counterboring.
In Fig. 373 a home-made counterbore is shown. Straight
shank A may be held in a chuck; head or body B is slightly
larger than head of bolt or screw; guide C fits body-drill hole;
and D and D' are the cutting lips which show clearance.
Counterbores with straight or taper shanks are obtainable
in sets of three: one with head the size of screw head and
with guide the size of body drill; one with head the size of
COUNTER COUNTER SPOT COUNTER
SUNK FACED BORED FACED SUNK
FlG. 374. COUNTERBORED AND COUNTERSUNK HOLES
FOR BOLTS AND SCREW HEADS.
screw head, and guide the size of tap drill; and one with head
of body size and guide the size of tap drill to enlarge a tap-
drill hole in a cap to body size. They are used similarly to
a twist drill and with a speed of from one-half to two-
thirds that of twist drills of same diameter of counterbore
head. A fine hand feed is generally used for spot facing and
deep counterboring.
For rough work a fast speed and a coarse feed may be
used, but for fine work use a medium speed and a fine feed.
For deep counterboring power feed may be used of about
one-half to two-thirds that used for twist drills, and the
counterbore withdrawn occasionally to remove the chips or
it will clog and break.
Attention. A counterbore often glazes the surface of cast
iron or hard steel and will not cut unless it is roughed up by
indentations with a chisel.
Note. Cast iron is counterbored dry, but if the guide is
a close fit it should be oiled.
COUNTERBORING AND COUNTERSINKING.
301
576. Counterboring a cap for fillister head screw, Fig. 375.
Cap E is clamped to table F by strap G, bolt H, and
block K. Commercial counterbore L has four cutting edges
with clearance on the ends. After the holes are drilled each
FIG. 375. COUNTERBORING FOR SCREW HEADS.
hole may be alined with the counterbore and counterbored, or
each hole may be counterbored after drilling and before the
setting is disturbed. Test depth of counterboring with the
screw head. See Fig. 374. See 646-648:
577. Counterbores with separate bodies and guide bush-
ings are obtainable so that various diameters of bodies and
guide bushings may be used on the same shank, or stem and
guide. They are obtainable in sets for the different sizes of
screw heads.
302
PRINCIPLES OF MACHINE WORK.
578. Counterbore or facing bar with inserted cutter, Fig.
376. Interchangeable cutters and guides may be used for
counterboring or spot facing bosses in the regular way or
on the lower side by feeding spindle upward. It consists of
i
SOCKET A
FIG. 376. COUNTERBORE OR FACING BAR.
socket A slotted to receive carbon or high-speed steel cutter
B. The cutter is centered, and guide bushing C is held in
place by conical pointed set screw D, and lock nut E. This
tool may be fitted also to the footstock spindle of an engine
lathe and used to bore cored work.
Important. A quick method of making a counterbore or
facing bar is to drill a hole through a bar, insert a piece of
tool steel for cutter, fasten with a set screw, turn and file
cutting edges, then harden and temper.
579. A countersink, Fig. 377, is a tool used to make a con-
centric conical enlargement at. the end of a hole to provide
STRAIGHT SHANK
FIG. 377. COUNTERSINK TO PROVIDE SEAT FOR HEAD OF
FLAT-HEAD SCREWS.
a seat for a conical-shaped screw head as in Fig. 374, and the
process is called countersinking. Countersinks are obtainable
SIZE OF STOCK TO MILL SQUARE OR HEXAGONAL. 303
with straight or taper shanks, with or without a guide. The
head is large enough for several diameters of screw heads.
The cutting edge is backed off for clearance at A.
The included angle for screw heads, both metal and wood,
ranges from 72 to 82, and this countersink of 72 will answer
for this range of angles.
Tire bolt heads are 54 and sleigh shoe bolt heads, 35.
CALCULATING DIAMETER OF BLANK TO MILL SQUARE OR
HEXAGONAL
580. Diameter to turn work to mill or file square is the
product of diameter across the flats multiplied by 1.414.
Example. Fig. 378. What diameter must a piece be to
mill square 1 J" across the flats?
Solution. 1.250" X 1.414 = 1.767" or Iff" diameter of
blank.
FIG. 378. DIAGRAM TO TURN
CYLINDER TO MILL SQUARE.
FIG. 379. DIAGRAM TO TURN
CYLINDER TO MILL HEXAGONAL.
581. Diameter to turn work to mill or file hexagonal is
the product of the diameter across the flats multiplied by
1.155.
Example. Fig. 379. What diameter must a piece be to
mill hexagonal 1J" across the flats?
Solution. 1.250" X 1.155 = 1.444" or 1||" diameter of
blank.
304
PRINCIPLES OF MACHINE WORK.
INDEXING IN ENGINE LATHE.
582. To index in engine lathe, Fig. 380. To file round
work square or hexagonal, or to drill diametrically through
a shaft, equidistant lines may be drawn on the work to
facilitate the operations.
FIG. 380. INDEXING IN THE LATHE.
SCHEDULE OF OPERATIONS.
To divide tap shank circumfer-
ence into four equal parts, A,B,C,
D, Fig. 3 SO. Select engine lathe
with headstock gear divisible by 4,
as 72 * 4 = 18. Count headstock
gear and mark divisions with chalk.
Mount blank E on centers with
wedge F between dog and face
plate to prevent back-lash. Use
pointed tool G to mark line H re-
quired distance from end.
Place file / against under side
of chalked tooth; rotate lathe
until file touches headstock at J.
With the left hand press the
handle downward until file touches
the bed at K and hold it in this
position.
With the right hand operating
cross feed, move tool to lightly
touch work, then change the
right hand to long, feed handle
and move the carriage to make a
line with the tool. For the other
lines repeat at the other chalked
teeth on gear. Two lines are
also shown at A.' B'.
CHAPTER XVIII.
INSIDE CALIPERS AND INSIDE MICROMETERS. BORING AND
INSIDE THREADING. SQUARE THREADS. ACME STANDARD
OR 29 THREADS. MULTIPLE THREADS. ALINEMENT
DRILLING AND TAPPING. ECCENTRIC TURNING.
TESTING LATHE WORK WITH INDICATORS.
INSIDE CALIPERS AND INSIDE MICROMETERS.
583. To set inside calipers. Fig. 381. Hold rule A perpen-
dicularly against carriage B. Place calipers C with point at D,
FIG. 381. SETTING INSIDE CALIPERS.
and adjust nut E until other point coincides with middle of
line F.
Another method is to set calipers to a standard ring gage,
or to a hole of the desired diameter in any piece of work.
584. To measure diameters of holes with inside calipers.
Work to be measured may be held in any position on the bench,
305
306
PRINCIPLES OF MACHINE WORK.
in vise or chuck. To measure work G, Fig. 382, in chuck H,
set calipers K to size and insert point M in the lower side
of hole, and steady with finger while a gentle effort is made to
FIG. 382. MEASURING WITH INSIDE CALIPERS.
insert point N, pivoting calipers on point M by raising and
lowering the outer end; also move point N to right and left to
locate maximum diameter.
585. To adjust the tool to bore a hole to diameter to which
inside calipers are set. Take trial cuts and test frequently with
calipers. See 588, 589.
586. Small inside micrometer calipers, Figs. 383, 384 and
385, are obtainable in two sizes, one measuring from two-
.252"
FIG. 383. MEASURING WITH V INSIDE MICROMETER.
tenths of an inch to one inch, and the other from one inch to
two inches.
INSIDE CALIPERS AND INSIDE MICROMETERS. 307
Except that the barrels are figured from right to left, they
are similar to outside micrometers having 40 threads to the
inch.
The reading of the one-inch micrometer in Fig. 383 equals
10 X .025 = .250" + .002 = .252" or J" + .002*.
NSIDE MICROMETER
FIG. 384. MEASURING BORE
OP BUSHING.
FIG. 385. MEASURING WITH
2" INSIDE MICROMETER.
In Fig. 384 a two-inch micrometer is shown as used to
measure the hole in bushing A.
Solid jaw B is placed against the lower wall of hole.
Sliding jaw C is moved against the upper wall of hole
by turning thimble D to right. The hole is bored out with a
boring tool (see 588, 589) until the. two-inch micrometer
reads 2 X .025" = .050".
1" + .050" = 1.050" diameter of bore of bushing, as in
Fig. 385.
587. Large inside micrometer caliper. Fig. 386 consists
of barrel A graduated into 40 divisions to the inch, thimble B
graduated into 25 divisions, attached to a screw having 40
308
PRINCIPLES OF MACHINE WORK.
threads to the inch, passing through a nut in end of barrel A.
The screw has a movement of half an inch. Measuring point
C is fixed to the thimble, but measuring point or rod D is
held in chuck E and clamped by nut F and is removable in
FIG. 386. MEASURING BORE OF CYLINDER WITH LARGE INSIDE
MICROMETER.
order to insert extension rods, a number being supplied vary-
ing in length by half an inch (-"), one being shown at G.
Adjustment for wear on rods is provided by adjusting nuts
H. Fig. 386 shows how the micrometer is used to measure the
bore of a cylinder. The net length of micrometer is 3" and the
reading is 3.200" + 2 X .025 = 3.250".
BORING AND INSIDE THREADING.
588. Boring tools. Fig. 387 shows a forged boring or in-
side turning tool. Cutting edges A and B must be shaped
with accuracy. The point is rounded slightly in order to make
TOP VIEW
\
FIG. 387. FORGED BORING TOOL.
it cut smoothly, and, also, not dull quickly ; if rounded too much,
the tool will spring away from the cut, or chatter.
BORING AND INSIDE THREADING. 309
589. To set and use boring tool in lathe. Fig. 388.
FIG. 388. BORING IN ENGINE LATHE.
SCHEDULE OF OPERATIONS.
1. True up cored work C in
chuck D and face front end.
2. Set tool E height of dead
center / as at H f , reverse tool
and post F into position parallel
to ways of lathe and clamp
tightly on G.
3. Run tool in length of hole
to see that shank clears walls,
also chalk top of tool to show
length of hole.
4. Rough bore hole and caliper
frequently.
5. Take two or three light
finishing cuts to leave hole smooth
and true. See 583-586.
Attention. A method sometimes used to bore a straight and
smooth hole is to take a light finishing cut inward, then reverse the
feed and let the tool cut outward.
Note. While a boring tool will cut satisfactorily if set at height of
centers, as H', Fig. 338, still the tool will cut better i set below the
centers, the amount increasing with the diameter of the hole, as is
inversely true with outside turning tools. See 72 74.
This, however, is not always possible, especially in small holes as
the size of tool will not allow sufficient clearance and will cause it to
ride on the wall of the hole, which must be avoided.
590. Squaring of an inside shoulder with the tool K, Fig.
389. L is a section taken at MN. The rounded point of
a boring tool leaves a fillet at the termination of the cut and if
310
PRINCIPLES OF MACHINE WORK.
a square shoulder is desired an inside squaring tool is used to
remove the fillet and square the shoulder by cutting to or from
the center.
M
L
N
FIG. 389. INSIDE SQUARING TOOL.
591. Boring holders and cutters are used in the same
manner as a forged tool. A, Fig. 390, shows holder and
double-end cutter rough boring
a cored hole, B, in work C.
For inside squaring a special cap
is supplied which holds the cutter
at an angle of 45 as at D. See
No. 20, Chart, Fig. 131.
At E, Fig. 391, a right-bent out-
side holder and cutter is shown
used as a boring tool and for
squaring and facing as at F.
FIG. 390.
BORING AND IN-
SIDE SQUARING
WITH HOLDERS
AND CUTTERS.
FIG. 391.-
BORING AND
FACING WITH
BENT HOLDER
AND CUTTER.
For boring long holes it is more practical to use drills, boring
bars, boring heads, etc.
592. Inside threading tools, United States Standard or Sharp
V threads. Fig. 392 shows point of inside threading tool. It
\
FIG. 392. INSIDE V-THREADING TOOL.
may be ground as at A and B for United States Standard or
Sharp V threads. It is similar to a boring tool. See No. 34,
Chart, Fig. 33.
BORING AND INSIDE THREADING.
311
The method of setting an inside United States Standard or
Sharp V-threading tool at right angles to the work is shown
WORKC
FIG. 393. SETTING UNITED STATES STANDARD OB
SHARP V-THREADING TOOL WITH CENTER GAGE.
in Fig. 393. Work C is held in chuck D and is bored to size
and end rough and finish squared. Tool E is then set to
gage F.
593. To cut an inside thread in lathe. Fig. 394.
FIG. 394. INSIDE THREADING IN ENGINE LATHE.
312
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS.
1. True up work G in chuck
H, and bore hole about gV' larger
than root diameter of screw
that it is to fit, and square end.
See Table of Tap Drills, 538.
See Screw Cutting, 226.
2. Assemble holder J, cutter
bar K, threading tool L, which
should be ground to fit thread
gage, and clamp in tool post M
supported by blocks N and N'
in tool block P.
Adjust tool to height of center,
set by gage F, Fig. 393, and
clamps bar and cutter firmly by
screw Q and cap R.
3. The cutter may be removed,
reground and reset to resume its
cut by means of cap R.
4. Clamp thread stop S to
slide T by screw U and adjust
feed of tool by rotating nurled
head W which is fast on screw V.
5. Rough thread with cuts
from .003" to .004" nearly to size.
Finish thread with cuts from .001"
to .002" until thread fits screw,
as follows:
Set outside calipers to the out-
side of the thread, then transfer
setting to inside calipers or to a
wire filed to fit outside calipers,
and pointed at each end more
acute than the thread. Cut
thread slightly smaller than inside
calipers or wire, then test it with
the screw.
If work is to fit a lathe spindle
or other work that cannot be
removed, take chuck and work
from lathe, clean, oil, and try on
the screw. If it does not fit
take another light cut, and so
on until desired fit is obtained.
Attention. If work is cast iron,
thread dry; if steel or wrought
iron, use lard oil.
Use oil for all materials when
fitting to screw or work may
seize screw and have to be split
off, thereby destroying work and
possibly the screw.
594. To finish tap the backing plate of a chuck, Fig. 395.
When cutting an accurate thread such as that in a backing
plate, A, of a chuck or face plate of a lathe, it is best, if a
suitable tap is available, to cut about three-quarters of a full
thread with a threading tool, then finish tap as in Fig. 395.
Clean and oil thread and tap and place tap wrench B on tap
C, and mount on dead center with tap in thread. Start tap
carefully so that it will follow the thread already cut and not
split and destroy it. Pull belt D by hand and follow tap with
dead center with handle E. To back out tap, unclamp foot-
stock and run lathe backward by hand or by power. Then
square up end F and bore out about two threads, as at G, to
BORING AND INSIDE THREADING.
313
permit screwing plate to shoulder on nose of spindle or on
a mandrel to be machined.
595. Interrupted thread tap, Fig. 395. Instead of using
adjustable tap C, with regular thread, preferably, use an
ENGINE LATHE GEAR HEADSTOCK
DH
INTERRUPTED
THREAD
TAP
H
FIG. 395. FINISHING THREAD WITH A TAP.
interrupted thread tap, as at H, which is obtainable. This
tap requires less power to drive it. Every other tooth is cut
away. The teeth of each land follow in the spaces of the land
preceding as shown by arrows J and K.
596. Engine lathe, gear headstock, Fig. 395, shows an
engine lathe equipped with a gear speed change located in the
head in place of the cone pulley. The different speeds and
positions of the levers L and M to obtain them are given
in a table at N.
Attention. Some all-gear headstock engine lathes have a
variable speed countershaft to give a still greater variety of
speeds.
This lathe is also equipped with a rapid change-gear
mechanism for feeds and threads. In a table at P are given
the different threads, and positions of the levers Q, R, and
314
PRINCIPLES OF MACHINE WORK.
S, to obtain them. The feed is usually seven times threads
per inch.
597. To cut right inside thread to shoulder. Fig. 396.
FIG. 396. CUTTING INSIDE UNITED STATES STANDARD OR SHARP
V THREAD TO A SHOULDER.
SCHEDULE OF OPERATIONS.
1. Work A, held in chuck B,
is bored to correct diameter and
depth.
2. Cut groove C to full diam-
eter of thread with inside form-
ing tool.
3. Mark line E with chalk to
indicate when tool D reaches
groove.
4. Cut thread to desired depth.
598. To cut a left inside thread to a shoulder, or any por-
tion of the hole less than its entire length, cut groove as at
C, Fig. 396, from which start tool outward, and make a
mark at E to know when to adjust the tool forward into
groove preparatory to starting to cut outward.
SQUARE THREADS.
599. Square threads, Fig. 397, right or left, are used for screws
to transmit motion, as the cross feed and lead screws of an
engine lathe, valve stems, presses, rock drill feed screws, etc.
It cannot be cut successfully with dies, or milled with a thread
milling machine. See Acme Standard or 29 Threads, 612.
SQUARE THREADS.
315
The thickness of thread and width of space are each nomi-
nally one-half the pitch. The depth is one-half pitch plus
the clearance. The fit is on the sides of the thread with
clearance top and bottom. A larger clearance is advisable for
large diameters and coarse pitchers.
5 THDS. TO 1 IN.
FIG. 397. SECTIONAL VIEW OF SQUARE THREAD SCREW AND NUT.
NAMES OF PRINCIPAL PARTS OF SQUARE THREAD.
C. Pitch.
D. Diameter standard.
E. Root diameter (which is
also root diameter of tap).
F. Diameter of bottom of
nut (which is also diameter of
tap).
G. Bore of nut.
H and H', clearances ; same for
all pitches. H made by cutting
the thread .005" deeper than P.
E' made by making tap. 01"
larger in diameter than D.
600. To obtain parts of Square thread.
Width of tool for screw thread =
No. of threads per inch
Width of tool for tap thread =
1
No. of threads per inch
2.
4-2-
316
PRINCIPLES OF MACHINE WORK.
.0005" for each linear inch of nut for shrinkage of tap.
Diameter of screw = any
Diameter of tap = diameter of screw + .010"
Diameter of screw or tap at root of thread =
diameter of screw
No. threads per inch
Diameter to bore nut = diameter of screw
No. of threads per inch
Clearance = .005", top and bottom of thread.
601. Table of Square threads. While any pitch may be
assumed, it is best, when it will answer the purpose, to use
whole numbers of threads per inch as near as possible to
three-quarters of the United States Standard thread. See
221.
DIAMETER.
THREADS
PER INCH.
DIAMETER.
THREADS
PER INCH.
y
10
V
6
r
9
\\"
5
r
8
If
4
i"
7
2"
3
602. Square threading Tool, Fig. 398.
T
B */o<V C
FIG. 398. OUTSIDE SQUARE THREADING TOOL.
A, top face, B, side view partially rotated, and C, end view.
DE and FG inclined to line QR to give clearance.
TO FIND INCLINATION OF THREAD.
317
TO FIND INCLINATION OF THREAD AND TO FILE TOOL.
SCHEDULE OF OPERATIONS.
SHEET METAL
H M K
FIG. 399. MAKING A TEMPLET AND SETTING GAGE TO ANGLE OF
INCLINATION FOR SQUARE THREADING TOOL.
Inclination. Fig. 399.
5. File to LM which gives
inclination of thread and use as
a templet to test tool or omit
filing and set angle gage U, Fig.
399, to angle LM as at V.
1. File line HK true.
2. Draw KL at 90 to HK.
3. Make KL equal to root
circumferences of thread.
4. Make MK equal to pitch.
X' X
FIG. 400. TESTING INCLINATION OF SQUARE THREADING TOOL
WITH ANGLE GAGE.
To File Tool.
1. File bottom of tool flat, and
end square as in Fig. 398. File
sides with an 8" or 10" hand
smooth file and 8" dead smooth
file to give inclination, clearance,
and size.
2. Test tool with gage U as at
X and X', Fig. 400, or with sheet
Fig. 400.
metal templet V, as in Fig. 399.
3. Measure with micrometer
calipers.
4. Harden and temper to a
straw color.
5. Grind on end and a little on
top.
Do not grind on sides.
Attention. The amount of inclination varies with different pitches
and diameters, but with a generous side clearance one tool will do
for several diameters. The tool is parallel from 0' to P, Fig. 398.
318 PRINCIPLES OF MACHINE WORK
For very coarse pitches tool is narrower at P than at 0'. For fine
pitches top face A is ground horizontal ; for coarse threads it is ground
on line ST at right angles to line QR.
Note. The tool may be forged, and ground to the proper angle
with a universal tool grinder, see Elements of Machine Work, then
hardened and tempered, reground and the filing omitted.
603. An outside Square threading holder and cutter is shown
at A and B, Fig. 401. Holder C supports cutter D. Clamp E
and bolt F fasten cutter to holder and hold different widths of
CUTTER !
*\
HOLDER C /
A B
FIG. 401. OUTSIDE SQUARE THREADING HOLDER AND CUTTER.
cutters. Cutter is ground upon end G only. Roughing and
finishing cutters are used for coarse threads. End H is for
left threads.
604. Method of setting outside Square threading tool.
Fasten tool A, Fig. 402, in tool-post lightly and adjust to
height of dead center. Mount screw blank B on centers.
SCREW BLANK
B
Mi |M ' |MMM J
mhiilililililiiilililililil
C
RULE
FIG. 402. SETTING SQUARE THREADING TOOL WITH
STEEL RULE.
Place steel rule C against blank parallel to axis and rap
tool until parallel to end of rule, testing from both sides as
at C and C'. Fasten tool firmly.
CUTTING A SQUARE THREAD SCREW.
319
605. An inside Square threading tool, Fig. 403, is used for
cutting inside threads. The blade A B is inclined, shaped
and sized to suit thread to be cut in the same manner as
the outside Square threading tool, Fig. 400, 602. Inside
B
\
FIG. 403. INSIDE SQUARE THREADING TOOL.
Square threads are cut also by inserting properly shaped
cutters in boring tool holders. See No. 23, Chart, Fig. 131.
606. Method of setting inside Square threading tool.
Nut blank C, Fig. 404, is held in chuck D. End E is faced
and hole bored to size. Place tool G in tool-post and adjust
to height of dead center (see No. 2, 589) and fasten lightly
CHUCK
D
SQUARE THREAD
NUT BLANK
TOOL G
RULE
-F
FIG. 404. SETTING INSIDE SQUARE THREADING TOOL.
in approximate position. Hold rule F against end E and
rap tool until blade of tool is parallel with rule. Then clamp
firmly.
320
PRINCIPLES OF MACHINE WORK.
607. Roughing tool. For Square threads, five pitch or
coarser, use a roughing tool .010" less in width, 0, Fig. 398,
than finishing tool.
608. Square thread tap l\" diameter, 5 threads to 1",
Fig. 405, is used to tap both loose and fixed nuts. Loose nuts
are usually rough threaded in the engine lathe with an inside
rough Square threading tool, Fig. 403, then finish threaded
with pne or more taps.
g
T
1.04"
i
T<C~
FIG. 405. SQUARE THREAD TAP, H x 5.
For fixed nuts such as parts of machine frames, one or two
roughing taps are used, followed with the finishing tap.
They are made without a leader as at A, Fig. 405, or with
plain or threaded leaders, A, Fig. 413. See Alinement Drill-
ing and Tapping, 626.
The diameter is made one-hundredth of an inch larger than
the screw for clearance. The root diameter is the same as the
screw. See 600.
Shank B is made about one-hundredth of an inch smaller
than the bore of the nut.
These taps cannot be obtained commercially, but must be
specially made.
609. To cut a Square thread screw, Fig. 406.
FIG. 406. SCHEDULE DRAWING OF SQUARE THREAD SCREW.
CUTTING A SQUARE THREAD SCREW.
321
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Preparing screw blank. Threading.
Material, machine steel iV' large; weight 3 Ib. 8 oz.
True live center.
Set dead center in approximate alinement.
Use high-speed steel cutting tools. See Exception, p. 59.
Time, 2 h. 15 min. with tools furnished.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Center.
Centering machine.
^" drill, 60 counter-
sink, lard oil.
Rough square, (1), (2).
Engine lathe 12" to
Dog, rule, calipers>
16". 2d or 3d speed,
side tool, 35 rake.
or 50 F.P.M. Hand
feed.
Recenter.
Speed lathe, drill, 4th
speed; countersink
3d speed.
Finish square, (1), (2).
Engine lathe, 3d or
4th speed or 80
F.P.M. Hand feed.
Rough turn -fa" large, (3), one
1st speed, or 40
Diamond-point tool
cut.
F.P.M. Medium
or holder and cut-
power feed 80 to
ter, 35 rake cali-
1".
pers, rule.
Set dead center in accurate
3d speed or 60 F.P.M.
Dog, copper, dia-
alinement to turn straight
Fine power feed
mond-point tool
using this piece or a trial
140 to 1".
or holder and cut-
piece the same length.
ter, 35 rake, mi-
See 41.
crometer.
Finish turn 1.25" +.003", (4).
3d speed, or 60 F.P.M.
Copper under set
Fine power feed
screw of dog, dia-
140 to 1".
mond-point tool or
holder and cutter,
35 rake, microm-
eter.
File 1.25" + .00 1", (5).
4th or 5th speed, or
8" or 10" mill bastard
175 F.P.M.
file.
Polish 1.25", (5).
Speed lathe, highest
60 and 90 emery
speed.
cloth, polishing
clamps.
Or rough turn .01" large, and
See Cylindrical Grind-
grind, after threading.
ing Machine, 379.
Drill hole, (6).
Speed lathe, drill
Center punch, &
chuck, 3d or 4th
straight shank twist
speed, or 1000
drill, V center, depth
R.P.M.
gage, lard oil.
322
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Concluded.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Grind square thread roughing
tool.
Set tool (see 604) and thread
stop, arrange lathe for 5
threads. Pull belt down-
ward to take up back-lash,
loosen set screw of dog
and adjust shaft until tool
terminates in hole, (6).
Tighten set screw.
Rough thread to 1.04" + .01*,
(7), twenty cuts .005" each.
Depth of thread .100".
Set finishing tool to cut on
both sides of groove by
loosening dog, adjusting
shaft and testing cut at end
thread. 1 ighten set screw.
Finish thread to 1.04", (8),
twenty cuts .005", two cuts
.002", one cut .001". Depth
of thread .105".
Turn off thick end thread, (9),
and smooth thread with file.
File top of threads to remove
burr.
File sides slightly.
Engine lathe. 1st
speed, or 25 F.P.M.
1st speed, or 25
F.P.M.
2d or 3d speed, or 50
F.P.M. Hand feed.
4th or 5th speed, or
175 F.P.M.
Slow speed for filing
sides of thread.
Forged Square thread
roughing tool, width
.090". See Fig. 398,
or use holder and
cutter, see Fig.
401, calipers, rule.
Lubricate freely
with lard oil.
Forged finishing tool,
width .100" + .002"
for fit, 1" microme-
ter, file, harden and
temper and grind
or use holder and
cutter, calipers,
rule, lard oil.
Diamond-point and
side tools, or holder
and cutter, 8" or
10" mill bastard file.
8" or 10" mill bastard
file.
Warding file.
Attention. Terminate each cut as follows: stop lathe when tool
is \ or \ revolution from hole, then carefully pull belt to continue cut
almost to hole and end the cut by moving tail of dog in slot of face plate.
Note. Roughing tool may be removed, ground, and reset if neces-
sary, but not the finishing tool.
SQUARE THREAD NUT.
323
610. To make a Square thread nut, Fig. 407.
TAP 1 J" DIA. 5 THDS. TO t"
IRON CASTING
CORED
Fia. 407. SCHEDULE DRAWING OF SQUARE THREAD NUT.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Preparing nut blank. Rough threading. Tapping.
Material, iron casting, cored; weight, 1 Ib. 6 oz.
Use high-speed steel cutting tools. See Exception, p. 59.
Time, 1 h. 15 min. with tools furnished.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Mount in chuck, true up and
Engine lathe 12" to
Independent chuck,
clamp hard in chuck.
16". 3d speed, or
chalk.
115 F.P.M.
Rough square, (1), one or two
2d or 3d speed, or 40
Round-nose tool, or
cuts.
F.P.M. Hand or
holder and cutter,
power feed.
15 rake.
Finish square, (1), one or two
3d or 4th speed, or 60
Facing tool or holder
cuts.
F.P.M.
and cutter, 15
rake.
Rough bore hole to about
1st or 2d speed, or 40
Boring tool, see 588.
1.03", (2), two or three cuts.
F.P.M. Medium
Inside calipers, rule.
power feed 80 to
1".
Finish bore hole, (2), two or
3d speed, or 60 F.P.M.
three cuts.
fine power feed
140 to I".
Or omit boring, bevel corner
2d or 3d speed, or 60
3 or 4-groove high-
of hole and drill to size.
F.P.M.
speed steel twist
drill (1.05").
See 282 and 478.
Set inside Square thread tool
2d speed or 50 F.P.M.
Forged Square thread
(see Fig. 404), and cut re-
Hand feed.
tool, width .090",
cess for improvised gage -fa"
or holder and cut-
X U", (3). See (A).
ter, inside calipers,
rule.
324
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Continued.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Arrange lathe for 5 threads
with thread stop reversed.
Rough thread to 1J" the di-
ameter of gage A, (4), fif-
teen cuts, .006" each, five
cuts, .002" each. Depth of
thread, .100".
Start tap in lathe, pull belt
downward and follow with
dead center. Be sure that
tap follows thread or it may
ream. Remove nut and
tap to reaming stand or
vise, and finish tapping, (5).
Mount nut on nut mandrel
and rough square, (6), one
or two cuts.
Finish square, (6), one or two
cuts.
Reverse nut and square to
length to remove recess,
(7), two or three cuts.
Rough turn, (8), one or two
cuts.
Finish turn, (8), one cut.
File, (9).
Nurl, two to four times, (10).
See Machine Nurling, 370.
File corners slightly to re-
move burr, (11),
1st speed, or 30 F.P.M.
Without oil.
Reaming stand or vise
and grooved wooden
jaws.
2d or 3d speed, or 40
F.P.M.
3d or 4th speed, or 60
F.P.M.
2d or 3d speed or 60
F.P.M.
1st or 2d speed, or 35
F.P.M. Medium
power feed 80 to
I".
2d or 3d speed, or 50
F.P.M.
4th speed, or 175
F.P.M.
1st or 2d speed, or 35
F.P.M. Medium
power feed 80 to
4th speed
F.P.M.
or 175
H"X 5 Square thread,
tap and tap wrench,
lubricate tap freely
with lard oil.
U"X5 Square thread
nut mandrel, dog,
round-nose tool, or
holder and cutter,
calipers, rule.
Facing tool or holder
and cutter.
Round-nose tool or
holder and cutter,
and facing tool,
calipers, rule;
Diamond-point tool
or holder and cut-
ter, 15 rake, cali-
pers, rule.
D i a m o n d-p o i n t or
round-nose tool, or
holder and cutter,
calipers, rule.
8* or 10" mill bastard
file.
Machine nurling tool,
medium pitch, oil.
8" or 10" mill bastard
file.
See Attention and Note, p. 325.
ACME STANDARD OR 29 THREAD.
325
Attention. In the absence of a tap an inside tool may be made
one-half pitch X .001" to finish the thread, but the thread will not
be as smooth or the fit of screw and nut as good.
Note. The nut in Fig. 407 is nurled for convenience in handling
as a problem. For practical styles of nuts to transmit motion, see
626.
611. To fit screw to nut. Figs. 406 and 407.
SCHEDULE OF OPERATIONS.
1. Ascertain if thread binds on
top or bottom by testing with
calipers and comparing with tap,
Fig. 405 ; if so, file top of threads
on screw or cut thread deeper.
2. Hold nut in grooved wooden
jaws in vise. ' Oil screw, grasp dog
with both hands and force in
with hand pressure.
3. If need be, file side of threads
with a warding file.
4. After screw is fitted to nut,
polish top of thread with 90
emery and clamps.
Attention. To file sides of a right thread, preferably, run lathe
backward at a slow speed, reverse file and file toward footstock.
ACME STANDARD OR 29 THREADS.
612. Acme Standard or 29 threads, Fig. 408, right or left,
are used for screws to transmit motion, as on lead screws, feed
5 THDS. TO 1 IN.
SCREW
A
FIG. 408. SECTIONAL VIEW OF ACME STANDARD OR
29 THREAD SCREW AND NUT.
screws, elevating screws, valve stems, presses, rock drills,
etc., and it is displacing the Square thread for other purposes
326
PRINCIPLES OF MACHINE WORK.
because it can be more readily cut in the lathe, and also
successfully and rapidly cut with dies, with bolt cutters and
turret lathes, and milled with thread milling machines.
For Thread Milling Machine, see Advanced Machine Work.
The depth of the thread is equal to one-half the pitch plus
.01" for clearance. The fit is on the sides with clearance on
top and bottom.
NAMES OF PRINCIPAL PARTS OF 29 THREAD.
C Pitch.
D Diameter, standard.
E Root diameter (which is
also root diameter of tap).
F Diameter at bottom of
thread on nut (which is also dia-
meter of tap).
G Bore of nut.
H and H' Clearances, same
for all pitches. (H obtained by
cutting thread .01" deeper than
%P; H', by making tap .02"
larger than diameter of screw.)
K Included angle 29.
L Side angle 14.
613. To obtain parts of thread.
Width of point of tool for screw or tap thread
.3707
No. threads per inch
Width of point of screw or nut thread
.3707
- .0052.
No. threads per inch
Diameter of tap = diameter of screw + .020.
Diameter of screw = any
Diameter of tap or screw at root of thread = diameter of
1
screw
No. threads per inch
1
Depth of thread = ~ ^- , ,
2 X No. threads per inch
Diameter to bore nut = diameter of screw
1
No. threads per inch
Clearance = .01" top and bottom of thread.
+ .020".
+ .010.
ACME STANDARD OR 29 THREAD.
327
TABLE OF THREAD PARTS FOR ACME STANDARD OR
29 THREAD.
PITCH.
No. OF
THREADS
PER INCH.
DEPTH OF
THREAD.
WIDTH AT
TOP OF
THREAD.
WIDTH AT
BOTTOM
OF THR'D.
SPACE AT
TOP OF
THREAD.
THICKNESS
AT ROOT OF
THREAD.
2
i
1.010
.7414
.7362
1.2586
1.2637
1J
A
.9475
.6950
.6897
1.1799
1.1850
li
4
.8850
.6487
.6435
1.1012
1.1064
1]
A
.8225
.6025
.5973
1 .0226
1 .0277
li
f
.7600
.5560
.5508
.9439
.9491
If
if
T 8 r
.7287
.6975
.5329
.5097
.5277
.5045
.9046
.8652
.9097
.8704
1*
H
.6662
.4865
.4813
.8259
.8311
11
.635
.4633
.4581
.7866
.7918
1ft
It
.6037
.4402
.4350
.7472
.7525
1|
1
.5725
.4170
.4118
.7079
.7131
1ft
If
.5412
.3938
.3886
.6686
.6739
i
i
.510
.3707
.3655
.6293
.6345
11
i&
.4787
.3476
.3424
.5898
.5950
i
' I 1 :
.4475
.3243
.3191
:5506
.5558
it
iA
.4162
.3012
.2960
.5112
.5164
I
ii
.385
.2780
.2728
.4720
.4772
H
i&
.3537
.2548
.2496
.4327
.4379
f
i
.3433
.2471
.2419
.4194
.4246
if
.3225
.2316
.2264
.3934
.3986
ll
.2912
.2085
.2033
.3539
.3591
i
2
.260
.1853
.1801
.3147
.3199
2f
2|
.2287
.210
.1622
.1482
.1570
.1430
.2752
.2518
-. .2804
.2570
1
2
.1975
.1390
.1338
.2359
.2411
3
.1766
.1235
.1183
.2098
.2150
A
3i
.1662
.1158
.1106
.1966
.2018
f
3j
.1528
.1059
.1007
.1797
.1849
*
4
.1350
.0927
.0875
.1573
.1625
f
4J .
.1211
.0824
.0772
.1398
.1450
I
5
.110
.0741
.0689
.1259
.1311
A
5*
.1037
.0695
.0643
.1179
.1232
i
6
.0933
.0617
.0565
.1049
.1101
1
7
.0814
.0530
.0478
.0899
.0951
i
8
.0725
.0463
.0411
.0787
.0839
{
9
.0655
.0413
.0361
.0699
.0751
A
10
.060
.0371
.0319
.0629
.0681
ft
16
.0412
.0232
.0180
.0392
.0444
328
PRINCIPLES OF MACHINE WORK.
614. Table of Acme Standard or 29 threads. While any
pitch may be assumed, it is best to use whole numbers of
threads per inch as near as possible to three-quarters of the
United States Standard. See 221.
DIAMETER.
THREADS PER
INCH.
DIAMETER.
THREADS PER
INCH.
Y
10
1"
6
5//
9
li"
5
V
8
iy
4
I"
7
2"
3
615. Acme Standard or 29 threading tool, Fig. 409. A is
top face, B and C are side and end views. For method of find-
ing inclination of thread, see Square Threading Tool, 602.
. TO FILE OR GRIND TOOL.
B ^'15-U. c
FIG. 409. ACME STANDARD OR 29 THREADING TOOL.
SCHEDULE OF OPERATIONS.
1. File bottom and end of tool.
2. File sides to fit gage D as at
E, Fig. 410.
3. Harden and temper to a
straw color.
4. Grind end until point F,
Fig. 409, will fit notch in gage as
at G, Fig. 410, the desired pitch.
5. Grind top face, A, Fig. 409,
slightly.
Attention. For fine pitches, use same tool for roughing and
finishing. For 5 pitch or coarser, rough with Square threading tool
.01" narrower than point of 29 tool. In case of very coarse pitches,
cut a square groove, then with right and left side tool cut down sides
of thread, after which use finishing tool of desired shape. A com-
pound rest is often used for coarse pitches.
Note. The tool may be forged and ground to the proper angle
with a universal tool grinder (see Elements of Machine Work}, then hard-
ened and tempered, reground, and the filing omitted. The thread is also
cut with 29 threading holder and cutter. See No. 16, Chart, Fig. 131.
TO FILE AND GRIND TOOL.
329
SCREW BLANK
H
9 8
76543
29 SCREW THD.
TOOL GAGE
D
14 2
<[
FIG. 410. SETTING TOOL TO CUT ACME
STANDARD OR 29 THREAD.
616. Method of setting outside Acme Standard or 29
threading tool. Fasten tool K, Fig. 410, in tool post lightly
and adjust to height of dead center. Mount screw blank H
on centers. Place gage D against screw blank H parallel to
axis and rap tool until angle of tool fits angle of gage. Then
fasten tool firmly.
617. An inside Acme Standard or 29 threading tool.
Fig. 411 is used for cutting inside threads. The blade A B is
inclined, shaped and ground to suit thread to be cut in the same
I/
TOP VIEW
B
\
SIDE VIEW
FIG. 411. INSIDE ACME STANDARD OR 29
THREADING TOOL.
manner as the outside Acme Standard or 29 threading tool,
Fig. 409, 615.
Inside 29 threads are cut also by inserting properly shaped
cutters in boring tool holders. See No. 24, Chart, Fig. 131.
330
PRINCIPLES OF MACHINE WORK.
618. Method of setting inside Acme Standard or 29 thread-
ing tool. Nut blank C, Fig. 412, is held in chuck D. End
E is faced and hole bored to size. Place tool F in tool post
FIG. 412. SETTING INSIDE ACME STANDARD 29
THREADING TOOL.
and adjust to height of dead center (see No. 2. 589) and
fasten lightly in approximate position. Hold gage G against
face of chuck D and rap tool until angle of tool fits angle of
gage. Then fasten tool securely.
619. Acme Standard or 29 thread tap 1J" in diameter,
5 threads to 1, Fig. 413, is used to tap both loose and fixed
nuts.
B
T
1.048"
i
T <C__
FIG. 413. ACME STANDARD OR 29 THREAD TAP 11 x 5.
Loose nuts are usually rough threaded in the engine lathe
with an inside threading tool, Fig. 412, to about J of a full
thread, then finish threaded with a tap.
CUTTING A 29 THREAD SCREW.
331
For fixed nuts, such as parts of machine frames, one or
two roughing taps are used, followed by the finishing tap,
preferably of type shown at H, Fig. 395. These taps are made
with leaders as at A or without leaders, A, Fig. 405. See Aline-
ment Drilling and Tapping, 626. The diameter is made two-
hundredths of an inch larger than the screw for clearance.
See 613. The root diameter of tap is the same as screw.
Leader A and shank B are two-thousandths of an inch
smaller than bore of nut, and the leader may be used as a
gage to test the bore of nut. These taps cannot be obtained
commercially but must be specially made.
620. To cut Acme Standard or 29 thread screw, Fig. 414.
5"
2) STOCK MACHINE STEEL (7) (D (9
FIG. 414. SCHEDULE DRAWING OF ACME STANDARD OR 29
THREAD SCREW.
SCHEDULE OF OPERATIONS, MACHINES, AND TOOLS.
Preparing screw blank. Threading.
Material, machine steel rg" large; weight, 3 Ib. 8 oz.
True live center.
Set dead center in approximate alinement.
Use high-speed steel cutting tools. See Exception, p. 59.
Time, 2 h. 15 min. with tools furnished.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Center.
Centering machine.
fa" drill, 60 counter-
sink, lard oil.
Rough square, (1), (2).
Engine lathe 12" to
16". 2d or 3d
speed, or 50 F.P.M.
Hand feed.
Dog, rule, calipers,
side tool, 35 rake.
Recenter.
Speed lathe, drill, 4th
speed; countersink,
3d speed.
332
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Continued.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Finish square, (1), (2).
Engine lathe, 3d or
4th speed, or 80
F.P.M.
Rough turn fa" large, (3), one
1st speed, or 40
Diamond-point tool
cut.
F.P.M. , medium
or holder and cut-
power feed 80 to
ter, 35 rake, cali-
1".
pers, rule.
Set center in accurate aline-
3d speed or 60 F.P.M.
Dog, copper, dia-
ment to turn straight using
Fine power feed
mond-point tool or
this shaft or a trial piece the
140 to 1".
holder and cutter,
same length. See 41.
35 rake, microm-
eter.
Finish turn 1.25" + .003", (4).
3dspeed,or60F.P.M.,
Copper under set
fine power feed
screw of dog, dia-
140 to 1".
mond-point tool or
holder and cutter,
35 rake, microm-
eter.
File 1.25* + .001", (5).
4th or 5th speed, or
8" or 10" mill bastard
175 F.P.M.
file.
Polish 1.25", (5).
Speed lathe, highest
60 and 90 emery cloth,
speed.
polishing clamps.
Cut groove, (6), to root diam-
Engine lathe, 1st or
29 grooving tool, cal-
eter of thread, 1.03".
2d speed, or 25
ipers, rule, lard oil.
F.P.M. Hand feed.
Grind Square thread 29
Engine lathe, 1st
Forged Square thread
roughing tool.
speed, or 30 F.P.M.
(29 roughing tool)
Set tool (see 604) and thread
width .060", see
stop, arrange lathe for 5
Fig. 398, or holder
threads.
and cutter, see Fig.
401.
Rough thread to 1.03" + .02",
Calipers, rule; lubri-
(7), twenty cuts .005" each.
cate freely with lard
Depth of thread, .100".
oil.
Set finishing tool to cut on
1st speed, or 25
Forged 29 finishing
both sides of groove by tak-
F.P.M.
tool, ground to fit
ing up back-lash, loosening
angle and notch 5
dog, adjusting shaft and
on gage, Fig. 410,
testing cut at end thread.
or use holder and
Finish thread, (8), twenty
cutter, calipers,
cuts of .005" each, two cuts
"
rule, lard oil.
of .002" each. Then take 1
cut .001", clean, oil, and
test and repeat until screw
fits nut. Depth of thread
.110". See (8).
29 THREAD NUT.
333
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Concluded.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Turn off end of thread, (9),
and smooth off thread with
file.
2d or 3d speed, or 50
F.P.M. Hand feed.
Diamond-point and
side tools, or holder
and cutter, 8" or
10" mill bastard
file.
File top of threads to remove
burr.
8" or 10* mill bas-
tard file.
File sides of thread slightly if
needed to make the fit
Slow speed for filing
sides of thread.
Warding file.
easier.
Polish tops of threads.
Speed lathe, highest
speed.
90 emery, polishing
clamps.
Attention. Terminate each cut as follows: stop lathe when tool
is ^ or ^ a revolution from groove, then carefully pull belt to continue
cut to groove.
A hole instead of a groove is sometimes used in which to terminate
the cut. See K, Fig. 397.
For fine pitches a groove, or hole, is sometimes omitted and a taper-
ing termination used the same as United States Standard and Sharp V
threads. See Fig. 157.
Warning. Roughing tool may be removed, ground, and reset, if
necessary, but it is best not to remove the finishing tool until thread
is completed.
Important. A 29 thread nut must be made first in order to fit the
screw to it.
621. To make an Acme Standard 29 thread nut, Fig. 415.
TAP IT" DIA. 5THDS.TO l"
IRON CASTING
CORED
FIG. 415. SCHEDULE DRAWING OF ACME STANDARD
OR 29 THREAD NUT.
334
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Preparing nut blank. Rough threading. Tapping.
Material, iron casting, cored; weight, 1 Ib. 5 oz.
Use high-speed steel cutting tools. See Exception, p. 59.
Time, 1 h. 15 min. with tools furnished.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Mount in chuck, true up, and
clamp hard in chuck.
Rough square, (1), one or two
cuts.
Finish square, (1), one or two
cuts.
Rough bore hole to about
1.03", (2), two or three cuts.
Finish bore hole 1.05, (2), two
or three cuts.
Or omit boring, bevel corner
of hole and drill to size.
Set inside 29 thread tool, Fig.
412, cut recess for impro-
vised gage & X 1?, (3).
.See (A).
Arrange lathe for 5 threads
with thread stop reversed.
Rough thread to l\" the di-
ameter of gage A, (4), fif-
teen cuts .006" each, five
cuts .002" each. Depth of
thread .100".
Start tap in lathe, pull belt
downward and follow with
dead center. Be sure that
tap follows thread or it may
ream out thread. Remove
nut and tap to reaming
stand or vise, and finish tap-
ping, (5).
Engine lathe 12" to
16". 3d speed, or
115 F.P.M.
2d or 3d speed, or 40
F.P.M. Hand or
power feed.
3d or 4th speed, or 60
F.P.M.
1st or 2d speed, or 40
F.P.M, medium
power feed 80 to
1".
3d speed, or 60 F.P.M.
Fine power feed
140 to 1".
2d or 3d speed, or 60
F.P.M.
2d speed, or 50 F.P.M.
Hand feed.
1st speed, or 30 F.P.M.
Reaming stand, or
vise and grooved
wooden jaws.
Independent chuck,
chalk.
Round-nose tool or
holder and cutter,
15 rake.
Facing tool or holder
and cutter, 15
rake.
Boring tool, 588. In-
side calipers, rule.
3 or 4-groove high
speed steel twist
drill (105").
See 282 and 478.
Forged 29 thread
tool, or holder and
cutter, inside cali-
pers, rule.
Without oil.
1J" X 5, 29 thread
tap and tap wrench.
Lubricate tap freely
with lard oil.
MULTIPLE THREADS.
335
SCHEDULE OF OPERATIONS, MACHINES AND TOOLS.
Concluded.
OPERATIONS.
MACHINES, SPEEDS,
FEEDS.
TOOLS.
Mount nut on nut mandrel
and rough square, (6), one
or two cuts.
Finish square, (6), one or two
cuts.
Reverse nut and square to
length to remove recess,
(7), two or three cuts.
Hough turn, (8), one or two
cuts.
Finish turn, (8), one cut.
File, (9).
Nurl, (10), two to four times.
See Machine Nurling, 370.
File corners slightly to remove
burr, (11), (12).
2d or 3d speed, or 40
F.P.M.
3d or 4th speed, or 60
F.P.M.
2d or 3d speed, or 60
F.P.M.
1st or 2d speed, or 35
F.P.M. Medium
power feed.
2d or 3d speed, or 50
F.P.M. 4th speed,
or 175 F.P.M.
1st or 2d speed, or 35
F.P.M. Medium
power feed 80 to
I*.
4th speed, or 175
F.P.M.
\\" X 5, 29 thread
nut mandrel, dog,
round-nose tool or
holder and cutter,
calipers, rule.
Facing tool, or holder
and cutter.
Round-nose tool, or
holder and cutter
and facing tool.
Diamond-point tool
or holder and cut-
ter, 15 rake, cali-
pers, rule.
Diamond-point or
round-nose tool, or
holder and cutter,
calipers, rule. 8"
or 10" mill bastard
file.
Machine nurling tool,
medium pitch, lard
oil.
8" or 10" mill bastard
file.
Attention. In the absence of a tap the inside 29 thread tool may
be used to finish the thread but the thread will not be as smooth or
the fit of screw and nut as good.
Note. The nut in Fig. 415 is nurled for convenience in handling
as a problem. For practical styles of nuts to transmit motion, see 626.
MULTIPLE THREADS.
622. Multiple- threaded screws, such as double and triple
threads, etc., in Square, 29, and other forms of threads, are
used in cases where a quick lead is required, but a deep
thread is not desirable.
336
PRINCIPLES OF MACHINE WORK.
623. To cut double Square thread, Fig. 416, 8 threads to
1", pitch ".
FIG. 416. DOUBLE SQUARE THREAD SCREW.
SCHEDULE OF OPERATIONS.
1. Gear lathe to cut 4 threads
per inch. Dog the work and with
threading tool trace a line for
groove 1.
2. At end of line center punch
and drill finishing hole A to ter-
minate groove 1 . See 609.
3. Cut groove 1 to diameter.
4. If ratio of stud spindle
and lathe spindle is 1 to 1, and
stud gear has an even number
of teeth, mark with chalk a tooth
on stud gear and the correspond-
ing space in idler gear. Then
mark a tooth on stud gear dia-
metrically opposite, which is de-
termined by counting half the
teeth in the stud gear.
Disengage idler gear from stud
gear, rotate lathe spindle and
bring gears into mesh as indi-
cated by chalk marks on the
teeth of the gears.
5. Now, with threading tool
trace a line for groove 2 and on
this line opposite A, center punch
and drill finishing hole A' (not
shown) to terminate groove 2.
6. Cut groove 2 to diameter.
Attention. To cut a triple thread, the lathe spindle is rotated one-
third of a revolution to cut the second thread, and another third to cut
the third thread. If gear on stud is not divisible by number of threads
to be cut, select change gears that have a stud gear that is.
Important. Special face plates with multiple equidistant slots
(index milled) are convenient for cutting multiple threads, as
the tail of the dog can be more readily shifted than the gears
after each thread is cut.
624. Width and inclination of tool for multiple threads.
The width or shape of tools for multiple threads is governed by
pitch of the screw; and the inclination by the lead of the screw.
625. Multiple-thread taps are similar to those for square
and 29 thread nuts. See 608, 619. The Sharp V and 29
forms of this thread can be cut with dies.
ALINEMENT DRILLING AND TAPPING.
337
ALINEMENT DRILLING AND TAPPING.
626. Fixed nuts, Fig. 417, which receive screws to trans-
mit motion are made in various forms, as bushing nut A,
which is threaded and forced into a bored hole and used to
STOCK BRONZE
OR MACHINE STEEL
STOCK BRONZE
OR IRON CASTING
FIG. 417. BUSHING AND BRACKET NUTS.
receive vertical feed screw on a milling machine, or bracket nut
B, used to receive cross-slide screw on a lathe, or bracket
nut C, Fig. 418, for cross-slide screw on a milling machine.
Bracket nuts are drilled and tapped in alinement with
scraped slide and bearing of screw, and the work may be
done with a regular jig, or with a part of the machine itself
used as an improvised jig, as knee B, Fig. 418.
LEFT HAND
29 OR SO. THD.
TAP
G
FIG. 418. ALINEMENT DRILLING AND TAPPING, MILLING MACHINE
CROSS-FEED SCREW NUT. HOLE IN KNEE USED AS A JIG.
627. To drill and tap cross-feed screw nut in axial aline-
ment in milling machine saddle and knee, Fig. 418. Impro-
vised jig, 29 or Square thread tap.
338
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS.
Place saddle A on -knee B. Fit
and bolt nut C to saddle and
move close to hole D.
Clamp saddle and knee to angle
plate at vertical drilling machine
or to table of horizontal drilling
machine and aline with spindle.
In hole D' insert jig bushing E,
and drill nut with tap drill F.
Move saddle and nut away
from hole D, and clamp saddle.
Remove bushing, insert tap G,
and tap hole by hand. Three or
four taps of increasing diameters
are used.
Attention. Taps without lead-
ers are used, but taps with lead-
ers, either threaded or plain, as
at H, are preferred for accuracy.
ECCENTRIC TURNING.
628. Eccentric turning. Besides ordinary straight and
taper turning, in which there is only a single axis and a single
pair of centers, there is another class of turning, known as
eccentric or offset turning, in which there is more than one
axis and consequently more than one pair of centers.
629. Laying out and turning an eccentric shaft, Fig. 419,
which has a throw of three-eighths of an inch.
FIG. 419. SCHEDULE DRAWING OF ECCENTRIC SHAFT FOR BACK GEARS.
SCHEDULE OF OPERATIONS.
1. Center stock as at A A'
Fig. 419. Rough and finish
square ends in regular way.
Rough turn diameter.
2. Coat with copper sulphate.
Lay out eccentric centers BB', dis-
tance at C, as follows: Mount
shaft on centers, clamp pointed
tool in tool post and make short
lines at each end in same plane
as at (1) and (2) Fig. 420. Draw
radial lines on each end as at D
with pointed tool or center square
and scriber. Slant pointed tool
to the left with point &" (half
the required throw of eccentric)
from lathe center and draw lines at
both ends intersecting radial lines
ECCENTRIC TURNING.
339
SCHEDULE OF OPERATIONS. Concluded.
as at E. Make center punch marks
at these intersections, and drill and
countersink in the regular way.
Mount in lathe on these eccen-
tric centers BB', Fig. 419, and
measure throw with test indicator,
see 637, or use paper between lathe
tool and work. Scrape over coun-
ter-sinks with center scraper, Fig.
420, to correct throw, or make
throw uniform at both ends.
Rough turn and rough square
reduced portions FF'. Change
to regular centers AA f , and finish
turn large diameter. Change to
eccentric centers BB, finish turn
reduced portions FF' and finish
square shoulders.
File diameters to remove tool
marks and fit to quill or gage.
Attention. To save time in
making a number of eccentric
shafts, make a jig to drill and
countersink ends.
ECCENTRIC SHAFT BLANK. CENTER HOLE SCRAPER.
FIG. 420.
630. To turn engine eccentric, Fig. 421.
ENGINE
ECCENTRIC
I
ECCENTRIC
MANDREL
FIG. 421. TURNING AN ENGINE ECCENTRIC.
SCHEDULE OF OPERATIONS.
1. Make eccentric mandrel Fig.
421, of required throw by method,
629.
2. Chuck, ream, and push ec-
centric casting lightly onto man-
drel. Mount in lathe and rap
eccentric until it runs true.
Take from lathe and press man-
drel hard. On large eccentrics,
set screws are used to fasten
eccentric to mandrel. Do all
facing operations and turning of
340
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS. Concluded.
hubs on regular centers AA', and
all eccentric diameters on eccen-
tric centers BB'.
Attention. When eccentric
centers lie outside shaft, eccentric
may be turned on disk, carrying
split stud with expanding screw,
the whole being bolted to face
plate of lathe in position to give
desired throw. Some prefer
this fixture to an eccentric man-
drel.
631. Crankshaft turning, Fig. 422. One of the most com-
mon forms of eccentric turning is an engine crankshaft.
Here the centers or axes lie outside of the shaft, so that fix-
tures, arms or flanges, carrying the centers must be provided.
ea
FIG. 422. WORKING DRAWING OF TWO-THROW 90 ENGINE
CRANKSHAFT.
Crankshafts are made with one or more cranks and may
have solid eccentrics as well. Small crankshafts, in the
rough, may be obtained drop-forged, of machine steel, cut
from steel slabs or in steel castings. The larger sizes come
partly machined after being forged under the steam hammer.
632. To lay out two-throw 90 crankshaft center fix-
tures, Fig. 423.
4.9497
FIG. 423. LAYING OUT A CENTER FIXTURE FOR A
TWO-THROW 90 ENGINE CRANKSHAFT,
ECCENTRIC TURNING.
341
SCHEDULE OE OPERATIONS.
1. In two fixture castings
chuck and ream holes to next
regular diameter larger than re-
quired diameter of ends of crank-
shaft, mount on mandrel and
square arms and hub. Plane
edges AB, at right angles and an
equal distance from hole.
2. Set pointed tool 3" from
point of dead center and describe
arcs CD. If fixtures are not
planed, points CD are obtained
as follows:
Center punch point on C, in
middle casting on the arc. Set
dividers 4.9497" the hypoth-
enuse of right triangle whose
base is 3", using the one-hun-
dredth graduation of the rule, and
with C as center intersect arc
at D. Distance CD, may be
obtained by the following rule:
Find the square root of the sum
of the squares of the two throws.
Example: Vs^ 2 + 3 2 =
4.9497, answer. Lines EF, on
each fixture are used to aline
cranks with fixtures when sides
of fixtures are not 90.
Attention. If only one crank-
shaft is to be turned, the fixture
may be drilled and countersunk
in casting. For a number of
crankshafts, chuck large holes
and drive in hardened and ground
steel plugs carrying large center
holes.
To make thes3 holes in correct
location, clamp fixtures to face
plate of lathe with marks C and D,
in axis of rotation as tested with
axis indicator (see Lathe Axis
Indicator, 279), then drill and
bore to size.
633. To aline center fixtures and lay out cranks, Fig. 424.
CENTER
FIXTURE
C
CENTER
FIXTURE
C
FIG. 424. LAYING OUT TWO-THROW 90 ENGINE CRANKSHAFT AND
ALINING CRANKS WITH CENTER FIXTURES.
342
PRINCIPLES OF MACHINE WORK.
SCHEDULE OF OPERATIONS.
To adjust fixtures, center and
square shaft in relation to crank
webs.
Turn AB to fit center fixtures
CC".
Mount fixtures and adjust
centers of cranks D and E to
aline with centers of fixtures by
wedges F and test with surface
gage. Lay out crank web by
lines and center punch at G, H,
K, L, M, N, P, Q.
Mount in lathe on one pair of
crank centers and revolve; reg-
ular centers are horizontally op-
posite. Test top of turned ends
with surface gage.
634. To turn crankshaft, Fig. 425.
FIG. 425. TURNING A TWO-THROW 90 ENGINE CRANKSHAFT.
SCHEDULE DRAWING.
SCHEDULE OF OPERATIONS.
Rough turn blank. Mount up-
on regular centers A A', Fig. 425.
Rough square faces of webs 1, 2,
3, 4, and rough turn shaft 5, 6,
and 7.
Change to crank centers BB'.
Rough square and turn 8, 9, and
10.
Change to crank centers CC'
and rough square and turn 11, 12,
13.
Counterbalance crank fixtures
by using weight D, or preferably
by adjustable weights EE'.
Use driver FF' with piece of
leather to reduce jar.
TESTING LATHE WORK WITH INDICATORS 343
SCHEDULE OF OPERATIONS. Concluded.
Season crankshaft between
roughing and finishing, if time
will permit.
Finish square and turn in
reverse order.
It is best to spot 7 and use
steady rest for finishing. For
slender crankshafts use jack or
braces as shown by dotted lines.
European tool post G is preferred
to a single tool post. Mill or
plane edges of webs.
Attention. Crankshaft lathes are obtainable. Automobile and
motorboat crankshafts may b3 rough turned, then ground, or ground
direct from drop forgings or steel castings. See Advanced Machine
Work.
TESTING LATHE WORK WITH INDICATORS.
635. Test Indicators, as in Figs. 426, 427, are used to deter-
mine the degree of accuracy of machine parts by enlarging
the error by a multiplying mechanism so that T oVy" will
register about T V' on scale or dial which is easily read and
fractions thereof readily estimated.
They are used to test the truth and alinement of machine
parts on either interior or exterior work ; as, the truth of live
centers, the alinement of dead centers to turn straight or
taper, the truth of mandrels and arbors, to set finished work
in chuck by hole or side, to set jig work or face plate of lathe,
to test eccentricity of shaft in straightening, to set cathead
or shaft to turn spot for steady rest, to test taper hole in
lathe or other spindles, to aline lathe heads in machine build-
ing, to aline cross rail or planer, to aline work on planer platen,
to test the accuracy of table with drill spindle, to test the
truth of milling machine arbor, to aline angle plates and
vises on milling and planing machines, to set work to center
mark on face plate of lathe.
636. Lathe test indicators. Fig. 426 shows an indicator
testing the truth of a mandrel mounted on lathe centers.
Holder A is held in tool post B, the cross slide is moved inward
until feeler or contact point C touches mandrel D as it is being
revolved by hand and the pointer indicates on the scale E the
amount, if any, in thousandths of an inch or fraction thereof,
344
PRINCIPLES OF MACHINE WORK.
that the mandrel is out of true. Feeler C is for testing man-
drels, centers, etc., and is removable.
Feeler F is for test-
ing interior or exterior
work and registers
either a horizontal or
perpendicular move-
ment. Feeler G is
broad faced and is
used for testing the
accuracy of a shaft
when filing. Feeler
H is for small work,
either internal or ex-
ternal, and for narrow
spaces.
Important. When
setting the indicator,
it is best to move feeler
C against the work
until the pointer on the scale is at zero (0).
Fig. 427 shows the method of setting a center punch mark
on work true to the axis of rotation.
The work is clamped lightly to the
face plate in an approximate posi-
tion. Spring plunger A is in-
serted in center punch mark B and
mounted on dead center C. The
work D is revolved by hand and
the truth of the plunger is tested
with the indicator. The work is
adjusted by rapping until plunger
A is motionless when the work is
revolved.
637. Dial test indicator. Fig.
428 shows a dial test indicator.
To enlarge the hole in gear A which is mounted in chuck
FIG. 426. TESTING THE TRUTH OF A MANDREL
WITH A LATHE TEST INDICATOR.
FACE PLATE
FIG. 427. SETTING A CENTER
PUNCH MARK TRUE TO Axis
OF ROTATION WITH LATHE
INDICATOR.
TESTING LATHE WORK WITH INDICATORS 345
DIAL TEST
INDICATOR
the indicator is used to test the truth of hole preparatory to
boring and reaming. Holder C is held in tool post D. The
long, feed is moved and the
rise and fall rest adjusted
until feeler of hole attach-
ment E touches wall of hole
in gear A. The gear is re-
volved by hand and the
pointer on dial F indicates
the axial truth of gear.
The gear is adjusted in
chuck and wall of hole
tested until pointer on dial
F is motionless or within a
reasonable limit, as j^Vo
of an inch or a fraction
thereof. The face of the
gear is also tested by using
indicator without attach-
ment E. The dial is divided
into 125 spaces of one-half
thousandth of an inch each.
Different feelers, as at G and H, are for various classes of
work. Clamp / is to fasten indicator to lathe and planer tools
and milling machine arbors.
Fig. 429 shows a dial test indicator
comparing the throw of an eccentric
shaft. The diameter of shaft must be the
same at both ends. One end is tested,
then shaft is reversed and second end tested.
Slight corrections are made by scraping
eccentric center holes, one of which is
shown at A, with center scraper as in Fig.
420.
Attention. To test side of gear, re-
move hole attachment E, Fig. 428, set dial
vertical and use indicator direct.
FIG. 428. TRUING UP A GEAR IN A
CHUCK WITH A DIAL TEST INDICATOR.
>. COMPARING
THE THROW OF BOTH
ENDS OF AN ECCEN-
TRIC SHAFT BLANK
WITH A DIAL TEST
INDICATOR.
CHAPTER XIX.
TABLES AND OTHER DATA USED IN MACHINE WORK.
638. Electrical units.
VOLT. The unit of electro-motive force, (E.M.F.) The
force required to send one ampere of current through one
ohm of resistance.
AMPERE. The unit of current. The current which will
pass through one ohm resistance when impelled by one volt
A milli-ampere = one-thousandth of an ampere.
OHM. The unit of resistance. The resistance offered to
the passage of one ampere when impelled by one volt. The
megohm = one million ohms.
WATT. The unit of power:
One ampere X one volt one watt.
Amperes X volts = watts. .
(Amperes) 2 X ohms = watts.
(Volts) 2 -f- ohms = watts.
746 watts = 1 horse power.
1000 watts = 1 kilo watt,
approximately 1J horse power.
COULOMB. The quantity of current which impelled by
one volt would pass through one ohm in one second.
JOULE. The unit of work. The work done by one watt
in one second.
346
TABLES AND OTHER DATA.
347
639. International and French Standard threads.
I* p >| Diameter and pitch in Metric Measure.
Formula
p = pitch.
d = depth = p X .64952.
FIG. 430.
640. International Standard thread.
si
1
DlAM.
cc
fc
H-t y
1
DlAM.
si
1
DlAM.
PJ ^
H
AT ROOT
W a
H
AT ROOT
II
H
AT ROOT
fl
5
OF
H S
M M
5 g
OF
H j
5
OF
B j
THREAD,
1 3
B J3
THREAD,
B ^
THREAD,
5^
P
M/M.
a*
I s
M/M.
^ "si
a
M/M.
6
1.0
4.70
20
2.5
16.75
48
5.0
41.51
7
1.0
5.70
22
2.5
18.75
52
5.0
45.51
8
1.25
6.38
24
3.0
20.10
56
5.5
48.86
9
1.25
7.58
27
3.0
23.10'
60
5.5
52.86
10
1.5
8.05
30
3.5
25.45
64
6.0
56.21
11
1 5
9.05
33
3.5
28.45
68
6.0
60.21
12
1 75
9.73
36
4.0
30.80
72
6.5
63.56
14
2 o
11.40
39
4.0
33 80
76
6.5
67.56
16
2.0
13.40
42
4.5
36.15
80
7.0
70.91
18
2.5
14.75
45
4.5
39.15
641. French Standard thread.
si
1
P
DlAM.
g|
1
DlAM.
si
1
DlAM.
l!
fel
S g
AT ROOT
OF
|
5 |
AT ROOT
OF
ij
BJ
AT ROOT
OF
C3 ^
t$ iJ
B ^
THREAD,
1 d
B ^
THREAD,
S j
O [j
THREAD,
11
S
M/M.
3^
S
M/M.
M ^
fi^
M/M.
3
0.5
2.35
16
2.0
13.40
36
4.0
30.80
4
0.75
3.03
18
2.5
14.75
38
4.0
32.80
5
0.75
4.03
20
2.5
16.75
40
4.0
34.80
6
.0
4.70
22
2.5
18.75
42
4.5
36.15
7
.0
5.70
24
3.0
20.10
44
4.5
38.15
8
.0
6.70
26
30
22 10
46
4.5
40.15
9
.0
7.70
28
3.0
24 10
48
5.0
41.51
10
.5
8.05
30.
3.5
25 45
50
5.0
43.51
12
.5
10.05
32
3 .5
27 45
14
2.0
11.40
34
3.5
29.45
348
PRINCIPLES OF MACHINE WORK.
642. The Society of Automobile Engineers' standard screws
and nuts.
E x
p = pitch.
d = depth
p X 64,952.
/
fl .t-f.
FIG. 432. UNITED STATES
STANDARD THREAD. For sizes of tap drills, see 537, 643.
Diameter of screw = nominal diameter .001".
Thread = U. S. S. in form but with finer pitches. Taps and
dies are marked U.S.F.
Heads and nuts are semi-finished but smaller than U. S. S.
Screws soft. Plain nuts soft. Castle nuts case-hardened.
Nuts should be a good fit on screw without perceptible shake.
The tap is from .002" to .003" larger than standard at the top
of thread to give the screw clearance in the nut. Material
for screws and nuts, machine steel; tensile strength, 100,000 Ibs.
per square inch; elastic limit, 60,000 Ibs. per square inch.
Threaded portions of screw should be one and one-half times
the body diameter.
Attention. The castle nut is used where a positive lock-
ing system is desired.
Important. It is best to use U.S.S. threads on soft material
such as aluminium and cast iron; and also on brass and bronze
if subjected to great strains.
TABLES AND OTHER DATA.
349
jo aaxaivviQ
aaxxoQ
jo aaxsivviQ
OUNLV STLSVQ MI
jo
3XLSVO
jo aaxaivviQ
os'iv 'xn^ QNV
aV3J H3QN 1 ONI
-.ovj ^1
sxo^g
OS^V
xnoiajj
JO SS3NHOIHJ,
M
IN COIN
"fr ^4* 1HP5 HN
avajj NI
xcng
avajj MI
xcng
avaanj,
JO
avan
H
QNV avsji
JO
sasNaoQ ssoaoy
avajj
JO
sxv^ l ^I;
^| ,_i ^H rH r-1 (N <N
Aciog
jo sa^ig
jo sazig
eavaaHj,
Aiaaog
jo aaxawviQ
350
PRINCIPLES OF MACHINE WORK.
644. Table of United States Standard bolt heads and nu's.
i
t
H
It
If
If
If
2i
2*
.25
.3125
.375
.4375
.5
.5625
.625
.75
.875
.125
.25
.375
.5
.625
.75
.875
2.25
2.5
2.75
3.25
-
PM
i
M
B
B
20
18
16
14-
13
12
11
10
9
8
7
7
6
6
54
5
5
44
Sf
.185
.2403
.2996
.3447
.4001
.4542
.5069
.6201
.7307
.8376
.9394
1.0644
1.1585
1.2835
1.3888
1.4902
1.6152
1.7113
.9613
.1752
.4252
.6288
D
.0056
.0069
.0078
.0089
.0096
.0104
.0114
.0125
.0139
.0156
.0179
.0179
.0208
.0208
.0227
.0250
.02^0
.0278
.0278
.0313
.0313
.0357
E
H
fl
1?
2f
P-H <
s
H O
g fc
G
.61
.75
.88
.01
.14
.28
.41
.67
1.94
2.20
2.47
2.74
3.00
3.27
3.53
3.70
4.06
4.33
5.39
5.93
6.45
6.98
H
A
1
It
If
It
If
It
2
2t
24
THICKN
HEAD.
i
tl
I
if
Attention. A bolt is usually threaded a distance equal to twice the body
diameter.
TABLES AND OTHER DATA.
351
645. Formulas of bolt heads and nuts. While finished,
heads and nuts (U. S. S.) are often made T y smaller than
the rough, it is best to make both the same size and to use
the same wrench.
The short diameter or width across flats = J X (diameter
of bolt) + J".
The long diameter or distance across corners of square
head or nut = short diameter X 1.414.
The long diameter of hexagonal head or nut = short diam-
eter X 1.155.
Thickness of nut = diameter of bolt.
Thickness of head = J short diameter of head.
646. Screw sets may be grouped in blocks as in Fig. 433,
see Table, 647, which consists of tap drill A, body drill B,
FIG. 433. SCREW SET GROUPED IN A BLOCK.
body counterbore C with tap drill guide and body cut, fillister
head counterbore D with body guide and head cut, gage E
for testing depth of fillister head, hexagonal square head
counterbore F with body guide and head cut, center chisel G,
352
PRINCIPLES OF MACHINE WORK.
taper tap H, plug tap /, bottoming tap K, and tap wrench L.
For countersunk head screws, a countersink is used as at M .
Important. The body counterbore C is for counterboring
body holes in caps where both cap and base are drilled with a
tap drill, and gives .a better alinement than when the cap is
drilled with a body drill.
Attention. A gib or fillister special head counterbore, with
tap drill guide, is used to counterbore a tapped hole, as at N,
Fig. 433, to receive the head where a screw head is used for
adjustment as the gib on the cross slide of some engine lathes
and other machine tools.
Note. A screw set may consist of a full set of tools, as
in Fig. 433, for screws of a particular size for any of the stand-
ard shaped heads, but blocks with fewer tools are often
arranged for special work.
Information. Counterbores are often made with inter-
changeable guides held in place by a pin, as at F r , Fig. 433.
647. Table of Screw Sets for Blocks United States Standard.
RE
ER
f
B
1 a o
n iJ <
H-9 a
gW
Is
* H
H
C
If
COUNTER
FOR SPO
15
W K
si
H
r
ii
ifl
TAPS.
PLUG,
TOMING
32
rSi
1*95
S 3
3
2
02
^ 5
.V
1%
C
N
s
p
H
TABLES AND OTHER DATA.
353
COUNTER-
FOR FILLI
HEAD GI
SCREW
iot^Oi-icocoooCT>
?.
his
IM
iaog
?Ot^
iOcOl^C>i-i-^t>ci
XQQ
iaog
S
-
' iTticO
COt^OOOli-^
H
!
xaQ iaog
(T>t>-
""M 6 6 6 6 ^ 66666
^OM^PHtC" 100
S *
a -
354 PRINCIPLES OF MACHINE WORK.
649. Stove bolts and rods.
&
FIG. 434.
DIAMETER OF BOLT IN INCHES.
&
ft
&
i
A
1
Threads per inch. -
28
24
22
18
18
16
650. Carriage bolts.
FIG. 435.
DIAMETER or BOLT IN INCHES.
I
ft
I
A
\
I
I
1
1
Threads per inch
20
18
16
14
13
11
10
q
8
651. Weights of castings from wooden patterns.
MATERIALS OF PATTERNS
Pine
Mahogany . .
16*
15
a
18 18 | 18 6
14 14 I 14
23
652. Estimating weight of
cored castings.
One cubic inch of metal weighs
653. Shrinkage of castings.
METAL.
LB.
Iron
2627
Composition
3023
Yellow brass
2997
Copper . .
3135
Bronze
306
Aluminium
0926
Steel
281
Lead
415
Zinc . .
.26
METAL.
IN.
PER
FOOT.
Iron
Composition
A
Yellow brass
1
Copper
A
Bronze or gun metal
Aluminium
2
Steel
^
Lead
A
Zinc . .
X
TABLES AND OTHER DATA.
355
654. Shrink rules, that is special rules with graduations
wider than standard measurement, are used for measuring
when making patterns so that the pattern will be large enough
to allow for contraction of casting in cooling and produce
the proper size casting. These rules are obtainable with
different allowances of shrinkage for different metals, as
T V", T 1 /, T 1 /, T?/, F, fV, and y per foot.
655, Consecutive and comparative tables of different drill
sizes.
ENGLISH, METRIC, NUMBER, LETTER.
td
fc
i
%
$
g
DECJ
MALS OF
VN!N- H
o
hH
*
5
DECI-
MALS OF
ANIXCI
|
HH
%
a
B8
5
DECI-
MALS OF
AN INCH
80
0135
56
.0465
40
.098
79
.0145
A
.046875
2.5
.098425
A
01 562. 5
1 2
047244
39
.0995
El
4
01574
1 3
051181
38
.1015
78
016
55
.052
2.6
.102362
77
018
54
055
37
.104
5
01968
1.4
055118
2.7
.1063
76
.020
1.5
.05905
36
.1065
75
.021
53
.0595
<TT
.109375
....
.6
74
73
.0225
.02362
024
&
l.Q
52
.0625
.06299
.0635
2^8
35
34
.11
.11024
.111
72
025
1.7
.066929
33
.113
..-..
.....
71
70
69
.026
.02756
.028
02925
i'.s
51
50
49
.067
.07
.070866
073
....
2.9
3
32
31
.11417
.116
.11811
.12
68
.031
1.9
.0748
3.1
. 12205
4r
03125
48
.076
*
.125
g
031496
A
.078125
3.2
.12598
67
032
47
.0785
30
.1285
66
.033
2
.07874
3.3
.12992
....
9
65
.035
03543
46
45
.081
082
....
3.4
29
.13386
.136
64
63
.036
037
2.1
44
.082677
.086
3.5
28
.1378
.1405
62
038
2.2
.086614
A
.140625
61
.039
43
.089
3.6
.14173
1
60
.03937
04
2.3
42
.09055
0935
....
3 7
27
.144
. 14567
59
041
A
09375
26
147
....
58
042
32
2 4
09448
25
1495
57
.043
41
.096..
3.8
. 14961
1 i
043307
356
PRINCIPLES OF MACHINE WORK.
Consecutive and comparative tables of different drill sizes.
Continued.
ENGLISH, METRIC, NUMBER, LETTER.
1
S
&
g
DECI-
MALS OF
AN INCH
1
*
X
g
5
DECI-
MALS OF
AN INCH
S
o
a
S
*
'
5
DECI-
MALS OF
AN INCH
24
.152
4.5
17717
M
203125
3 9
15354
15
18
6
204
23
154
4 6
1811
5 2
20473
jt
15625
14
182
5
2055
22
157
13
185
5 3
20866
4
.15748
4.7
.18504
4
.209
21
159
A
1875
5 4
2126
20
161
4.8
188Q8
3
213
4.1
.16142
12
189
5 5
21654
4.2
.16536
11
191
A
21875
19
.166
4 9
19291
5 6
22047
4 3
16929
10
1935
2
221
18
1695
g
196
5 7
22441
ii
.171875
5
. 19685
1
.228
17
173
8
199
5 8
22835
....
4.4
16
.17323
177
....
5.1
7
.20079
201
5.9
.23228
I
a
s
LETTER
SIZES.
DECI-
MALS OF
AN INCH
g
M
s
a
LETTER
SIZES.
DECI-
MALS OF
AN INCH
1
HH
3
S
N
H02
DECI-
MALS OF
AN INCH
A
234
H
266
N
302
H
234375
6 8
26772
7 7
30314
6
.23622
6 9
27165
7 8
30709
B
238
I
272
7 9
31102
6.1
.24015
7
27559
JL
3125
c
242
j
277
g
31496
6.2
.2441
7.1
27952
o
.316
D
246
J
281
8 2
32284
6.3
24803
A
28125
' * * "
p
323
i
E
.25
7 2
28347
21
328125
6.4
.25197
7 3
2874
Q
332
6.5
.25591
L
29
8 5
33465
F
257
7 4
29133
8 6
33859
6.6
.25984
M
.295
R
.339
G
261
7 5
29528
if
34375
6.7
26377
f
296875
8 8
34646
fi
265525
7 6
29922
g
348
TABLES AND OTHER DATA.
357
Consecutive and comparative tables of different drill
sizes. Continued.
ENGLISH, METRTC, NUMBER, LETTER.
IN.
M.M.
LETTER
, SIZES.
DECI-
MALS OF
AN INCH.
IN.
M.M.
DECI-
MALS or
AN INCK.
IN.
M.M.
DECIMALS
OF AN
INCH.
9
35433
A
5625
5|
859375
T
.358
14.5
.57087
22
.86614
ii
.359375
ii
.578125
i
.875
9.2
u
.36221
368
is'
15
.59055
.59375
il
22.5
.88583
890625
"i"
9.5
.37402
375
II
15.5
.609375
.61024
'*$'
23
.90551
.90625
V
377
I
.625
59
.921875
9 6
.37796
16
.62992
23.5
.9252
9 8
.38583
ii
.640625
4
.9375
'?T'
w
.386
.390625
ii
16.5
.6496
.65625
fi'
24
.94488
.953125
10
X
.3937
.397
17
.66929
.671875
'ir
24.5
.9646
.96875
Y
.404
40625
ft
17 5
.6875
689
M" "
25
.98425
984375
z
413
IT
703125
i
"n
10.5
.4134
421875
'i*'
18
.70866
.71875
iA
25.5
.004
015625
11
43307
18 5
.72835
26
.02362
j,.
4375
n
.734375
1A
.03125
11.5
45276
19
.74803
26.5
.0433
ii
.453125
.75
1A
.046875
#
.46875
49
.765625
ITS
.0625
12
.47244
19.5
.76772
27
.063
31
484375
78125
1A
078125
12 5
4921
20
7874
27 5
1 08268
i
5
44-
796875
IJL
1 09375
13
51181
20 5
8071
28
1 1024
33
515625
1%
.8125
1 7
1 109375
il
53125
21
. 82677
28 5
1 122
13 5
5315
53
.828125
It
1.125
fi
.546875
27
.84375
4
1 . 140625
.64
14
.55118
"5T
21.5
. 84646
29
1.1417
358
PRINCIPLES OF MACHINE WORK.
Consecutive and comparative tables of different drill sizes.
Concluded.
ENGLISH, METRIC, NUMBER, LETTER.
IN.
M.M.
DECIMALS
OF AN
INCH.
IN.
M.M.
DECIMALS
OF AN
INCH.
IN.
M.M.
DECIMALS
OF AN
INCH.
1A
15625
4375
44
1 7323
A 32
29 5
1614
129
45312
m
1 73437
IjU.
171875
37
4567
if
1 75
30
.1811
iM
.46875
44.5
1.7519
1 A
1875
37.5
.4764
1 76562
30 5
1 2008
.48437
45
7717
f- :
1 203125
38
.4961
IT!
.78125
1 21875
ii
.5
45.5
.79138
31
.2205
iff
.51562
14 i
.79687
Itt
31.5
.234375
.24016
"iii*
38.5
.51576
1.53125
lit
46
.811
1.8125
25
39
1 5354
in
1 82812
"\\l
32
.2598
26562
iff
39 5
1.54687
1 .5551
'111'
46.5
1.83
1 84375
32 5
2795
ift
1.5625
47
85047
i*
119
.28125
29687
40
.5748
.57812
iff
47.5
.85937
.87016
33
2992
ill
.59375
ii
.875
1A
3125
3S
40.5
.5945
48
.88985
* 16
33 5
319
Iff
.60937
111
.89062
iff
34
.328125
.3386
If
. 41
.6142
.625
if!
48.5
.90625
.90945
iu
.34375
41.5
.6338
lit
.92187
34 5
3583
141
64062
49
92913
114
359375
42
6536
iii
9375
l|
375
12 1
65625
49 5
9488
"i-ii
35
.378
1 39062
ill
42 5
.67187
.6733
ifi
50
.95312
.9685
35 5
1 3977
iu
.6875
I4i
.96875
lii
1 40625
43
.6929
iff
.98437
36
1 4173
iM
70312
50 5
9882
lii
1 421875
43 5
71259
2
2
*
36 5
1 437
iH
71875
51
2 0079
TABLES AND OTHER DATA.
359
656. Morse tapers with diagram and table of proportional
parts.
For holes in drilling machine spindles, lathe spindles, shanks
of drills, sockets, end mills, etc.
REAMED
TAPER
HOLE
|* ANY *
ANY
TAPER
PLUG
GAGE
TAPER
SHANK
GAGE I
rh rh
1
I I
FIG. 436. DIAGRAM OF MORSE TAPERS.
SOCKET OR
SPINDLE
360
PRINCIPLES OF MACHINE WORK.
sxoaroHj '
HOHOUHX
ox
!H.NVHg
'
sad aadvx
OX
xasoog
X
M
CO CO *"H CO
i ( I Oi 1C i I
iO>OOOOO
00
i-(
W 00 O O O
w t^ ec co eo
CO^COti-l
*U3COOOO(M000
OOOOi-Hr-ti-ii-i
WVIQ
dHVdNViLg
,IO HXJ3Q
HXJ3O; CQ
PQ
xa^oog ^o
ON3 XV 'TCVIQ
iH i- N CO
invwg xv
o -WVIQ
naavx
TABLES AND OTHER DATA.
361
658. Brown & Sharpe tapers with diagram and table of
proportional parts.
For holes in milling machine spindles, collets, and shanks
of arbors, end mills, etc.
DRILLED
HOLE
* ANY *
TAPER
REAMER
FIG. 437. DIAGRAM OF BROWN & SHARPE TAPERS.
362
PRINCIPLES OF MACHINE WORK.
659. Table of Brown & Sharpe tapers.
TABLES AND OTHER DATA.
363
JARNO TAPERS.
669. The Jarno taper system is 0.600" per foot (1 in 20)
for all numbers, and the number^ of the taper determines
all the other dimensions, as all parts are functions of the
number. For example, No. 4 taper is T V' at small end,
f" at large end, and f" (or 2") in length.
FIG. 438. JARNO TAPER IN GRINDING-MACHINE SPINDLE.
As there is -fa" in diameter between consecutive numbers
at small end and J" at large end, the number of a taper can
be readily found by rough measurement with rule, or rule
and calipers. Some prominent lathe grinding machine manu-
facturers have adopted the Jarno taper for holes in spindles,
and others retain the Jarno taper per foot but modify the
other specifications by changing the diameters or lengths to
suit special conditions.
364
PRINCIPLES OF MACHINE WORK.
661. Table of Jarno tapers.
Taper per foot= .6 inch. Taper per inch = .050 inch
JARNO TAPER O.6OO" TO I 1
NO. 4. FULL SIZE
Diameter of small end =
FIG. 439.
No '
Diameter of large end = No ' of ta P er .
8
Length of taper^ No. of taper ^
2
NUMBER.
"A."
"B."
"C."
2
.20
.250
1
3
.30
.375
U
4
.40
.500
2
5
.50
.625
2*
6
.60
.750
3
7
.70
.875
3*
8
.80
.000
4
9
.90
.125
4*
10
.00
.250
5
11
.10
.375
5*
12
.20
.500
6
13
.30
1.625
6*
14
.40
1.750
7
15
.50
1.875
71.
16
.60
2.000
8
17
.70
2.125
8*
18
1.80
2.250
9
19
1.90
2.375
9*
20
2.00
2.500
10
TABLES AND OTHER DATA.
365
i
366
PRINCIPLES OF MACHINE WORK.
1
e
I
&
2
pa
i
I
S
FOR BRO
PE TAPER
SETOV
<fe SH
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S3HONI NI
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TABLES AND OTHER DATA.
367
FOR BR
PS TAPE
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368
PRINCIPLES OF MACHINE WORK.
664. Table of decimal equivalents of American Screw Com-
pany's machine and wood screws.
The difference between consecutive sizes is .01316*.
No. OF
SCREW
GAGE.
SIZE OF
NUMBER
IN
DECIMALS.
No. OF
SCREW
GAGE.
SIZE OF
NUMBER
IN
DECIMALS.
No. OF
SCREW
GAGE.
SIZE OF
NUMBER
IN
DECIMALS.
000
.03152 -
16
.26840
34
.50528
00
.04468
17
.28156
35
.51844
.05784
18
.29472
36
.53160
1
.07100
19
.30788
37
.54476
2
.08416
20
.32104
38
.55792
3
.09732
21
.33420
39
.57108
4
.11048
22
.34736
40
.58424
5
.12364
23
.36052
41
.59740
6
.13680
24
.37368
42
.61056
7
.14996
25
.38684
43
.62372
8
.16312
26
.40000
44
.63688
9
.17628
27
.41316
45
.65004
10
.18944
28
.42632
46
.66320
11
.20260
29
.43948
47
.67636
12
.21576
30
.45264
48
.68952
13
.22892
31
.46580
49
.70268
14
.24208
32
.47896
50
.71584
15
.25524
33
.49212
TABLES AND OTHER DATA. 369
665. Table of standard mandrel dimensions.
I LARGE END
V-
TAPER. .006" PER FOOT
~\\ MANDRELS j^' TO I 1 , .0005" BELOW STANDARD AT SMALL END
l-f TO 2". .001
F E
FIG. 441.
a .
H 03
g
IS
H
S o
W H,
2
a ^ a
S 5 &
E
G
H
K
&
r
3
5i
5i
6
6i
f
A
A
k
B
II
tl
4*
1
A
I
A
r
TV
A
56
52
52
52
52
47
47
47
47
42
42
42
370
PRINCIPLES OF MACHINE WORK.
Table of standard mandrel dimensions. Concluded.
is
II
o
a ei
s s
8
D
E
G
H
K
7
7i
8
81
9
91
10
!o|
10f
11
1
1
1
1
A
H
"4
6 |
Ox
7
6i
8
81
tt
M
42
42
42
38
38
38
38
38
38
28
28
28
28
28
28
28
28
28
TABLES AND OTHER DATA.
371
666. Number of revolutions required to obtain surface
speeds of from 20 feet to 100 feet per minute.
DIAMETERS FROM IXCH TO 24
FEET
PER
MlN.
20
25
30
35
40
45
50
55
60
65
70
DlAM.,
INCHES.
REVOLUTIONS PER MINUTE.
*
152
191
229
267
305
344
382
420
458
496
535
f
101
127
152
178
203
228
254
279
305
330
356
1
76
95
114
133
152
172
191
210
229
248
267
H
68
85
102
119
136
153
170
187
204
221
238
H
61
76
91
106
122
137
153
168
183
199
213
H
50
63
76
89
101
114
127
139
152
165
178
i*
43
54
65
76
87
98
109
120
131
141
152
2
38
47
57
66
76
86
95
105
114
124
133
3
25
31
38
44
50
57
63
70
76
82
89
4
19
23
28
33
38
43
47
52
57
62
66
5
15
19
22
26
30
34
38
42
45
49
53
6
12
15
19
22
25
28
31
34
38
41
44
7
10
13
16
19
21
24
27
30
32
35
38
8
9
11
14
16
19
21
23
26
28
31
33
9
8
10
12
14
17
19
21
23
25
27
29
10
7
9
11
13
15
17
19
21
22
.24
26
11
6
8
10
12
13
15
17
19
20
22
24
12
6
8
9
11
12
14
15
17
19
20
22
13
5
7
8
10
11
13
14
16
17
19
20
14
5
6
8
9
10
12
13
15
16
17
19
15
5
6
7
8
10
11
12
14
15
16
17
'16
4
6
7
8
9
10
11
13
14
15
16
17
4
5
6
7
8
10
11
12
13
14
15
18
4
5
6
7
8
9
10
11
12
13
14
19
4
5
6
7
8
9
10
11
12
13
14
20
3
4
5
6
7
8
9
10
11
12
13
21
3
4
5
6
7
8
9
10
10
11
12
22
3
4
5
6
6
7
8
9
10
11
12
23
3
4
4
5
6
7
8
9
10
10
11
24
3
4
4
5
6
7
7
8
9
10
11
372
PRINCIPLES OF MACHINE WORK.
Number of revolutions required to obtain surface speeds of
from 20 feet to 100 feet per minute. Concluded.
DIAMETERS FROM IXCH TJ 24 INCHES.
FEET
PER
MIN.
75
80
85
90
95
100
105 110
115
120
125
DlAM.,
INCHES.
REVOLUTIONS PER MINUTE.
*
573
611
649
687
726
764
802
840
878
916
955
I
381
406
432
457
482
508
535
560
586
612
637
1
286
305
324
344
363
382
401
420
439
458
477
H
255
272
289
306
323
340
357
374
391
408
425
1*
228
245
260
274
290
306
321
336
351
367
382
1*
191
203
216
229
241
254
266
280
292
306
318
If
163
174
185
196
207
218
238
240
250
262
273
2
143
152
162
172
181
191
200
210
219
229
238
3
95
101
108
114
121
127
133
140
146
153
159
4
71
76
81
86
90
95
100
105
109
114
119
5
57
61
64
68
72
76
80
84
87
91
95
6
47
51
54
57
60
63
67
70
73
76
79
7
40
43
46
49
51
54
57
60
62
65
68
8
35
38
40
42
45
47
50.
52
55
57
59
9
31
34
36
38
40
42
44
46
48
51
53
10
28
30
32
34
36
38
40
42
44
46
47
11
26
27
29
31
33
34
36
38
40
41
43
12
23
25
27
28
30
31
33
35
36
38
39
13
22
23
25
26
27
29
30
32
33
35
36
14
20
21
23
24
25
27
28
30
31
32
34
15
19
20
21
23
'24
25
26
28
29
30
31
16
17
19
20
21
22
23
25
26
27
28
29
17
16
17
19
20
21
22
23
24
25
26
28
18
15
16
18
19
20
21
22
23
24
25
26
19
15
16
17
18
19
20
21
22
23
24
25
20
14
15
16
17
18
19
20
21
22
22
23
21
13
14
15
16
17
18
19
20
20
21
22
22
13
13
14
15
16
17
18
19
19
20
21
23
12
13
14
15
15
16
17
18
19
19
20
24
11
12
13
14
15
16
16
17
18
19
19
Attention. To calculate any cutting speed, see 96.
TABLES AND OTHER DATA.
373
667. A comparative table of different wire gage sizes in
general use in the United States.
IN DECIMAL PARTS OF AN INCH.
JM
H
a
h
R
I
fa O
o
sVfi
i|*
i: s
*. <9
fc ^ <
W
o
& _
1 .
i
w
fa O
o <
s
^ si S
is
o ^ O
h-4 r ji
1 5
*>
m
8
p
III
1 *
3 w .
K W
Jj OQ O
8s
Sis
S
w
i
1
DQ h
t?
j!
000000
.464
.46875
000000
00000
.432
.45
.4375
00000
0000
.46
.454
.3938
.400
.4
.40625
0000
000
.40964
.425
.3625
.372
.36
.375
000
00
.3648
.38
.3310
.348
.33
.34375
00
o
.32486
.34
.3065
.324
.305
.3125
o
1
.2893
.3
.2830
.300
.285
.227
.28125
1
2
.25763
.284
.2625
.276
.265
.219
.265625
2
3
.22942
.259
.2437
.252
.245
.212
.25
3
4
.20431
.238
.2253
.232
.225
.207
.234375
4
5
.18194
.22
.2070
.212
.205
.204
.21875
5
6
.16202
.203
.1920
.192
.19
.201
.203125
6
7
. 14428
.18
.1770
.176
.175
.199
.1875
7
8
.12849
.165
.1620
.160
.16
.197
.171875
8
9
.11443
.148
.1483
.144
.145
.194
. 15625
9
10
.10189
.134
.1350
.128
.13
.191
. 140625
10
11
.090742
.12
.1205
.116
.1175
.188
.125
11
12
.080808
.109
.1055
.104
.105
.185
. 109375
12
13
.071961
.095
.0915
.092
.0925
.182
.09375
13
14
.064084
.083
.0800
.080
.08
.180
.078125
14
15
.057068
.072
.0720
.072
.07
.178
.0703125
15
16
.05082
.065
.0625
.064
.061
.175
.0625
16
17
.045257
.058
.0540
.056
.0525
.172
.05625
17
18
.040303
.049
.0475
.048
.045
.168
.05
18
19
.03589
.042
.0410
.040
.04
.164
.04375
19
20
.031961
.035
.0343
.036
.035
.161
.0375
20
21
.028462
.032
.03175
.032
.031
.157
.034375
21
22
.025347
.028
.0286
.028
.028
.155
.03125
22
23
.022571
.025
.0258
.024
.025
.153
.028125 .
23
24
.0201
.022
.0230
.022
.0225
.151
.025
24
25
.0179
.02
.0204
.020
.02
.148
.021875
25
26
.01594
.018
.0181
.018
.018
.146
.01875
26
27
.014195
.016
.0173
.0164
.017
.143
.0171875
27
28
.012641
.014
.0162
.0149
.016
.139
.015625
28
29
.011257
.013
.0150
.0136
.015
.134
.0140625
29
30
.010025
.012
.0140
.0124
.014
.127
.0125
30
31
.008928
.01
.0132
.0116
.013
.120
.0109375
31
32
.00795
.009
.0128
.0108
.012
.115
.01015625
32
33
.00708
.008
.0118
.0100
.011
.112
.009375
33
34
.006304
.007
.0104
.0092
.01
.110
.00859375
34
35
.005614
.005
.0095
.0084
.0095
.108
.0078125
35
36
.005
.004
.0090
.0076
.009
.106
.00703125
36
37
.004453
.0068
.0085
.103
. 006640625
37
38
.003965
.0060
.008
.101
.00625
38
39
.003531
.0052
.0075
.099
39
40
.003144
.0048
.007
.097
40
374
PRINCIPLES OF MACHINE WORK.
668. Table of decimal equivalents of Stubs* steel wire gage.
LETTER
SIZES OF
LETTERS
IN
DECIMALS.
No. OF
WIRE
GAGE.
SIZES OF
NUMBERS
IN
DECIMALS.
No. OF
WIRE
GAGE.
SIZES OF
NUMBERS
IN
DECIMALS.
No. OF
WIRE
GAGE .
SIZES OF
NUMBERS
IN
DECIMALS.
Z
.413
1
.227
28
.139
55
.050
Y
.404
2
.219
29
.134
56
.045
X
.397
3
.212
30
.127
57
.042
W
.386
4
.207
31
.120
58
.041
V
.377
5
.204
32
.115
59
.040
u
.368
6
.201
33
.112
60
.039
T
.358
7
.199
34
.110
61
.038
s
.348
8
.197
35
.108
62
.037
R
.339
9
.194
36
.106
63
.036
Q
.332
10
.191
37
.103
64
.035
p
.323
11
.188
38
.101
65
.033
.316
12
.185
39
.099
66
.032
I N
.302
13
.182
40
.097
67
.031
M
.295
14
.180
41
.095
68
.030
L
.290
15
.178
42
.092
69
.029
K
.281
16
.175
43
.088
70
.027
J
.277
17
.172
44
.085
71
.026
I
.272
18
.168
45
.081
72
.024
H
.266
19
.164
46
.079
73
.023
G
.261
20
.161
47
.077
74
.022
F
.257
21
.157
48
.075
75
.020
E
.250
22
.155
49
.072
76
.018
D
.246
23
.153
50
.069
77
.016
C
.242
24
.151
51
.066
78
.015
B
.238
25
.148
52
.063
79
.014
A
.234
26
.146
53
.058
80
.013
27
.143
54
.055
TABLES AND OTHER DATA.
375
669. Table of different steel music wire gage in decimals
of an inch.
AMERICAN STEEL & WIRE CO.
H
H
O
> Q
t^ <<
H
3
ri
o
3
.
O
u W
S S
1?
O
B
PS
3
02 H
a jo 2
^
^
O w
b* H
H *
M
5i^
SS
gS
g
|
08
?
* i
H
n
g-
\ H
^ a
ffl
1
|
a
H ^
o
H
9
t>
|6*
63S
3
H
B
H
Q
I
1
w
fc
*
21
^
H
s
w
6.0
.4615
.004
5.0
.430
.005
4.0
.3938
.006
.007
.006
.0068
.006
3.0
.3625
.007
.0075
.007
.0075
.007
2.0
.331
.008
.0085
.008
.008
.0087
.008
1.0
.3065
.009
.009
.009
.009
.0093
.009
1
.283
.010
.010
.010
.010
.0098
.010
2
.2625
.011
.011
.011
.011
.0106
.0105
.011
3
.2437
.012
.012
.012
.012
.0014
.0115
.012
4
.225
.013
.013
.013
.013
.0122
.0125
.013
5
.207
.014
.014
.014
.014
.0138
.0145
.014
6
.192
.016
.016
.016
.016
.0157
.015
.016
7
.177
.018
.018
.018
.018
.0177
.0175
.018
8
.162
.020
.020
.020
.020
.0197
.019
.020
9
.1483
.022
.022
.022
.022
.0216
.022
.022
10
.135
.024
.024
.024
.024
.0236
.0245
.024
11
.1205
.026
.026
.026
.026
.026
.027
.026
12
.1055
.029
.028
.029
.029
.0283
.0285
.029
13
.0915
.031
.030
.031
.031
.0303
.0305
.031
14
.080
.033
.032
.033
.033
.0323
.032
.033
15
.072
.035
.034
.035
.035
.0342
.035
.035
16
.0625
.037
.036
.037
.037
.0362
.036
.037
17
.054
.039
.038
.039
.039
.0382
.038
.039
18
.0475
.041
.040
.041
.041
.0400
.040
.041
19
.041
.043
.042
.043
.043
.042
.042
.043
20
.0348
.045
.044
.045
.045
.044
.043
.045
21
.03175
.047
.046
.047
.047
.046
.0445
.047
22
.0286
.049
.048
.049
.049
.048
.047
.052
23
.0258
.051
.051
.051
.051
.051
.049
.055
24
.023
.055
.055
.055
.055
.055
.053
.059
25
.0204
.059
.059
.059
.059
.059
.056
.061
26
.0181
.063
.063
.063
.063
.063
.0605
.065
27
.0173
.067
.067
.067
.067
.067
.064
.070
28
.0162
.071
.071
.071
.071*
.071
.0685
.072
29
.015
.075
.074
.075
.075
.074
.0715
.077
30
.014
.080
.078
.080
.080
.078
.075
.083
31
.085
.082
.085
.082
- 32
.090
.086
.090
.086
33
.095
.090
.095
376
PRINCIPLES OF MACHINE WORK.
670. Table of decimal equivalents of United States Standard
sheet and plate steel and iron gage sizes.
NUMBER OF
GAGE.
APPROXIMATE
THICKNESS IN-
FRACTIONS or
AN INCH.
APPROXIMATE
THICKNESS IN
DECIMAL,
PARTS OF AN
INCH.
WEIGHT PER
SQUARE FOOT
IN OUNCES
AVOIRDUPOIS.
WEIGHT PER
SQUARE FOOT
IN POUNDS
AVOIRDUPOIS.
0000000
1-2
.5
320
20.00
000000
15-32
.46875
300
18.75
00000
7-16
.4375
280
17.50
0000
13-32
.40625
260
16.25
000
3-8
.375
240
15.00
00
11-32
.34375
220
13.75
5-16
.3125
200
12.50
1
9-32
.28125
180
11.25
2
17-64
.265625
170
10.625
3
1-4
.25
160
10.00
4
15-64
.234375
150
9.375
5
7-32
.21875
140
8.75
6
13-64
.203125
130
8.125
7
3-16
.1875
120
7.5
8
11-64
.171875
110
6.875
9
5-32
.15625
100
6.25
10
9-64
.140625
90
5.625
11
1-8
.125
80
5.00
12
7-64
.109375
70
4.375
13
3-32
.09375
60
3.75
14
5-64
.078125
50
3.125
15
9-128
.0703125
45
2.8125
16
1-16
.0625
40
2.5
17
9-160
.05625
36
2.25
18
1-20
.05
32
2.
19
7-160
.04375
28
1.75
20
3-80
.0375
24
1.50
21
11-320
.034375
22
1.375.
22
1-32
.03125
20
1.25
23
9-320
.028125
18
1.25
24
1-40
.025
16
1.
25
7-320
.021875
14
.875
26
3-160
.01875
12
.75
27
11-640
.0171875
11
.6875
28
1-64
.015625
10
.625
29
9-640
.0140625
9
.5625
30
1-80
.0125
8
.5
31
7-640
.0109375
7
.4375
32
13-1280
.01015625
6 1-2
.40625
33
3-320
.009375
6
.375
34
11-1280
.00859375
5 1-2
.34375
35
5-640
.0078125
5
.3125
36
9-1280
.00703125
4 1-2
.28125
37
17-2560
.006640625
4 1-4
.265625
38
1-160
.00625
4
.25
TABLES 4ND OTHER DATA. 377
671. Uses of different wire and plate gage sizes. The
American or Brown & Sharpe gage is used for copper and elec-
tric wire; Birmingham or Stubs' iron wire gage, for machine
steel and iron wire, also for sheet steel, iron, copper, brass, and
seamless tubing; American Steel & Wire Company's gage, for
steel wire; Imperial wire gage, for foreign work; Trenton Iron
Company's gage, for their own work; Stubs' steel wire gage,
for tool steel and drill rods; music (piano) wire (a tempered
steel wire), in machine construction for coil and other springs.
The new gage sizes run in even thousandths so that a microm-
eter may be used easily.
United States Standard plate gage is used for steel plate.
Attention. As wire and sheet-metal fixed gages are not very accurate, it
is best to use dimensions, not numbers, and to measure with a micrometer.
INDEX
Abrasives 106
Accurate drilling 242-247
hand tapping 274, 275
Accurate drilling, inspection circle for 244
Acme standard or Twenty-nine degree
thread 325-335
Adjustable reamers 141, 142
taps 271, 313
Alinement drilling and tapping 337, 338
of dead center 18, 19
Alining crankshaft center fixtures 341,342
Aluminium, to machine 187
Alundum grinding wheels 198-202
Allowances for driving fits 70
forcing fits 71
grinding 207
reamed, ground, and
bored holes 75, 76
reaming 139
running fits 69
shrinking fits 75
sliding fits 70
S. A. E. standard screws (bolts) and
nuts 348, 349
American Screw Company's machine
screws 297, 298, 363
A. S. M. E. standard machine
screws 295-297
Ampere 344
Angle iron or angle plate, boring with 133
drilling with
250, 251
Angles, cutting 27, 28
Apron, lathe 5-7
Approximate drilling 243
tapping 272-274
Arbor block 148
or mandrel press 74. 148, 149
Arbors or mandrels 146-154
Attachment, automatic tapping . . .266, 267
taper 84, 85
Attachments for lathes,
8, 17, 84, 85, 192, 194
Automatic dies 280
drill chuck and collet. . . 252, 253
drift 233
sizing grinder 218, 219
taps 271
Automobile bolts. See Automobile
screws
screws and nuts. 286, 348, 349
Babbitt, machining 187
Back gears, lathe 2-5
Back-lash 114
rests for grinding machines. .217-219
Backing plate with a tap, to finish
thread... ...312-314
Page
Bearings, lubricating or oiling 13
treatment of roughed-up . . 13
Belts, putting on and pushing off . ... 13, 14
Binding post, schedule of operations
for making 183-187
Birmingham or Stubs' iron wire gage
sizes 373, 377
Blocks, V 251
Body drills 236
Body drills, A. S. M. E. standard and
special machine screw
296, 297
American Screw Com-
pany's machine screw . 298
Boiler tube holes, cutter for drilling 254, 255
Bolt and nut making 121-125
Bolt heads and nuts, table and formu-
las for 303, 350, 351
Bolt and nut, schedule of operations
for making finished 124, 125
Bolts and nuts, automobile. See Auto-
mobile screws,
finished,
124, 125, 283, 350, 351
rough 283, 350, 351
semi-finished,
124,125,283,284,348-351
table of United States
standard 350
Bolts, carriage 354
classes of 282, 283
drilling for 248, 260-269, 300
expansion 285, 290
finished 124, 125, 283
hanger 290
headless 285
hexagonal-head 282, 283
improvised 283, 284
length of thread on 282
machine screw 293
measuring 282
planer-head 283, 284
square-head 248, 283
stove 354
stud 266, 267, 283, 284
tap 288
uses of 248, 282
Bolts and screws, spot facing for heads
of 300
Bore to setting of inside calipers, ad-
justing tool to 306
Boring in the engine lathe 306-310
in the speed lathe 178
tool holders and cutters 95, 310
with angle iron or angle plate . 133
Boring, squaring to shoulders in. .309, 310
Boring tool, grinding 43
Boring tools 29, 95, 308-310
Boring tools, setting 309
378
INDEX
379
Page
Box jigs for drilling, reaming, and tap-
ping 263-265
Brass turning in engine lathe 182-187
wire 373, 377
Brass binding post, making 183-187
Brass finishing, hand tools for 174-176
Brass, front tool for 182, 183
grinding twist drill for 232
rough hand turning 174-176
round-nose tool for 182, 183
twist drills for 232, 233
Bridges in hollow castings 147
British Association standard threads. 102
Broach reamers 144, 145
Bronze, grinding phosphor 221
machining 187
Brown & Sharpe tapers 361, 362
Burr when squaring, to remove 33, 34
Burnishing 176, 177
Burnt or hot centers 56
Bushing for counterbores 301
Bushing, making a 128
Calculating compound gearing for
threading 115, 116
diameter of blank to mill
or file square or hexa-
gonal 303
distance to set over foot-
stock for tapers 81, 82
simple gearing for
threading 110, 111
speeds and feeds for
drills 237-241
speeds and feeds for lathe
work 47-50
Caliper gages 77
squares 66, 67
Caliper, ten-thousandth microm-
eter 67
Calipers, adjusting tool to bore to set-
ting of inside 306
I adjusting tool to turn to
setting of outside 46
divider 23
inside 305, 306
large inside micrometer. .307, 308
measuring with inside. . . . 305, 306
with inside micrometer 306-308
measuring with micro-
meter 61-64
measuring with spring 45-47
vernier 65, 66
reading inside micrometer 306-308
vernier 66
micrometer 61, 62
vernier 65, 67
setting inside 305
outside 45
small inside micrometer. .306, 307
spring 45-47
thread 104
vernier 65-67
Calipers to another, to transfer set-
ting from one pair of 47
Cap, counterboring 301
Cap screws, collar 288
countersunk-head .... 288, 300
drilling for 248, 249,
264, 265, 300
fillister-head" 288, 289, 300
-head stud 288
Page
Cap screws, flat-head 288 300
hexagonal-head.. 287, 288, 300
oval-countersunk head
288, 300
fillister-head 288, 300
round-head 288, 300
square-head 248, 288
tapping for 248, 249
uses of 287, 288
Carborundum grinding wheels. . . . 198-202
Carriage bolts 354
Carriage, lathe 1-3
Castle nuts. .. 286, 348, 349
Cast iron, diamond-point tool for
finish turning 36, 37
diamond-point tool for
rough turning 36
drilling 230
hard 231, 232
finish facing 153
squaring 33, 34,96
large square-nose tool for
finish turning 36, 37
lathe tools for 27-37
rough facing 152
squaring 31
round-nose tool for finish
turning 36, 37
small square-nose tool for
finish turning 37
Cast-iron roll, grinding 216
Castings, drilling. . .231,248-251,260-269, 303
Castings, shrinkage of 354
estimating weight of cored. 354
Castings from wooden patterns,
weight of 354
Cat head 192, 193
Catch ing the thread in screw cutting . 118
Celluloid grinding wheels 198, 200
Center gage . 15
holes in lathe work 19-26
mandrels 149
punch 23, 24
reamers _^. 22, 24
Center, alinement of dead 18, 19
dead 1, 2, 15, 16
live 2, 3, 16-18
locating live 4, 16
table 256
V 256
Center drill, to remove broken 24
fixtures, eccentric 340, 341
Center-hole dimensions, table of 21
Center for pipe turning, revolving
dead....... 147
Center for squaring, grooved dead. . . 33, 34
Centering machine 25, 26
tool for chucking 135
Centering, squaring, and straight
turning, schedule of operations for 57-59
Centering work, hand method of 23, 24
machine method of. 25, 26
Centers, burnt or hot 56
grinding machine,
195-197, 204-206
grinding engine lathe 17
lathe 1, 2, 3, 16-18
mounting work on lathe,
20, 24, 54-56
testing angle of 15
truing engine lathe 16, 17
truing speed lathe 15-18
grinding machine. .204, 205
380
INDEX
Page
Centers in alinement, setting grind-
ing machine 206
Chamfering nut and bolt 123
Change gear mechanism for screw
cutting and feeds, rapid 8,9
Change gears 2, 3, 110-112, 115-117
Chart of forged lathe tools 28, 29
grinding wheels 199
Charts of lathe holders and cutters. . 94, 95
Chasers, hand 173, 174
Chattering of tools 91
Check nuts 285, 286
Chuck jaws 126
Chucking 134-138
an eccentric 129
a pulley 138
in speed lathe 170, 171
with drill holder and steady
rest 136
with twist drills. . . 135, 170, 171
Chucking, centering tool for 135
Chucking drills, flat 136-138
reamers, flat 137
fluted 143, 144
Chucking with a flat drill and chuck-
ing reamer in an engine lathe, sche-
dule of operations for 137, 138
Chucks 126-131, 232, 294, 295
Chucks, care of "130, 131
classes of 126
combination 129
draw-in 130, 294, 295
drill 127, 230, 232, 255-258
face-plate 130
independent 127
mounting and removing . . . 131
set screw 232, 255
special 127
spring ,.130. 294,295
tapping backing plates of 312-314
truing and holding work in
combination 129
truing and holding work in
independent 127
truing and holding work in
uni , ersal 128
universal 128
Chucks to machine spindles, attach-
ing 126,311-314
Clamp dog 121
Clamp nut, making a 123
Clamps, polishing 162
Clearance of counterbores 299, 300
dies 280
drills 225
hand tools 164
lathe tools 27, 28
reamers. 139
taps 271
Coil springs 179, 181
Cold punched nuts 285
Collar cap screws 288
Collet, to grind taper 220
Combination chucks 129
grinding wheels 200
Combination chucks, to true and hold
work in 129
Compound gearing for threads, calcu-
lating 115, 116
Compression springs 179
Copper wire 373, 377
Copper, machining 187
polishing 162, 163
Cored castings, estimating weight of 354
Corundum grinding wheels 198-202
Cotter, spring 286, 354, 355
Coulomb 346
Counterbore with inserted cutter. . . .' 302
Counterbore, forged 299, 300
Counterbores, clearance of 299, 300
Counterboring a cap 301
for screw heads 299-303
Counterbored holes 300
Counterbores 299, 301, 302
Counterbores, separate bodies and
guide bushings for 301
Countershaft, engine-lathe 2-4
speed-lathe 11, 12
Countersink for screw heads 302, 303
Countersinks 22-25, 302, 303
Countersunk holes,
19-21, 24, 25, 300, 302, 303
Counterweights on face plates 133, 342
Counting threads 104, 105, 113
Crank, laying out holes in engine. .132, 133
Crankshaft turning 340-343
Crankshaft center fixtures, schedule
of operations for laying out two-
throw 90 J 340, 341
Crankshaft center fixtures, alining 341, 342
Cross feed of lathe 5-7
Crowning or tapering pulleys. 15 6, 157, 159
Curve turning 190, 191
Cut meter 43
Cut, finishing ',,'.', 28
roughing 28
Cutters for tool holders 93-96, 98
Cutting angles 27, 28
4 double threads 335, 336
square threads 336
feeds for drills 237
metal plate by drilling 253
off stock. 97, 98
off wire in a universal hand
lathe 177, 178
screws 102-120, 124,
125, 172-174, 279-281, 294, 295
Cutting feeds, lathe 50
Cutting speeds for high-speed steel
lathe tools 49
Cutting speeds for hand tools 164
lathe tools 47-50
measuring 48, 49
Cutting-off tool holders and cut-
ters 93-95, 98
Cuttmg-off tool, breaking a 98
grinding 40, 41
improved hand. . . 177, 178
Cutting-off tools, lathe. . .29, 94, 95, 97, 98
Cutting tools, lathe 27-37, 87-98
lubricants for 50-52
theory of 27, 28
rake, clearance and cut-
ting angles of lathe. 27, 28
Cylinder heads, drilling and tapping
engine 262, 266, 267
Cylindrical grinding 195-221
Dead center, alinement of 18, 19
lathe 1, 2, 15, 16
Decimal equivalents, table of common
fractions and 64
Depth of cuts for grinding 208
Dial test indicator 344
INDEX
381
Page
Diameter to turn blank to mill or file
square or hexagonal 303
Diamond tool for truing emery wheels 204
Diamond-point tools for cast iron . . . 34-37
for steel or wrought
iron .... 88, 90, 91
Diamond-point tools, grinding 40, 43
half 29, 93
left 93
Dies, automatic 280
clearance of 280
machine-screw 294, 295
sharpening 280
threading .279-281, 294, 295, 326-336
Disks, reference 78
Divider calipers 23
Dividers, setting 242
using 242, 243
Dog, clamp 121
square 121
Dogs for grinding machine 195, 205
Dogs for grinding work of one diame-
ter, end-driving 205, 206
Dogs or drivers, lathe 20
Double threads 335, 336
tool holders 96
Dowel pins 289
Draw-in chucks 130, 294, 295
Drawing the drill 243-247
Drawings, schedule-of-operations . ... 54
Drill chucks 127, 230, 232, 255-257
drifts or center keys 230, 231, 233
gages 234-236
holder 136
Drill, drawing the 243-247
extension for 255
Drill chuck and collet, automatic. . 252, 253
drifts, automatic 233
gages, numbered 235, 236
Drill grinder, twist 227, 228
Drill sizes, consecutive and compara-
tive tables of different 355-358
Drilling 222-269
and counterboring duplicate
parts 268, 269
and tapping engine cylinder
heads 262. 266, 267
Drilling and tapping cross-feed screw
nut, alinement 337, 338
Drilling brass or composition 232, 233
castings,. 231, 248-251, 260-269, 300
cast iron 230
deep holes 258, 259
diametrically through shaft,
251-253, 256
flanges 260-264
flat or square work in speed
lathe 255-257
for bolts 248, 260-269, 300
screws and studs,
248, 249, 260-269, 300
set screws 158-160, 247
forgings 254-259
glass 52
hard cast iron 231, 232
hole in end -of shaft parallel
to axis in speed lathe 257
jigs 260-269
machine frames 243-251, 260
on a slanting surface 254
part of a hole 251
steel or wrought iron 230, 234
with flange jig 262
Page
Drilling wood 232
work held against angle
plate 250, 251
work held by hand, or- in
vise, on drilling table 250
Drilling, accurate 242-247
approximate 243
inspection circle for accurate. . 244
laying out work for,
242-244, 246-250
oil drills for deep 257-259
rough 243
Drilling, use of lead holes for 253, 254
Drilling boiler tube holes, cutter
for 254, 255
Drilling cored holes, three and four-
groove twist drills for 250, 251
Drilling, reaming and tapping,
schedule of operations for 246, 247
Drilling machine described, verti-
cal 222-224
Drilling machines, classes of 222
feeds of
222-224. 240, 241
multiple-spindle
262-264, 26?, 269
radial 265-268
speeds of,
222-224, 239-241
Drilling table, leveling work on 255
Drills for brass 232, 233
cast iron
230-232, 234, 237, 250, 251
hard steel ...231, 232
steel and wrought iron,
230-232, 234-237, 257-259
sheet metal 232, 233
Drills, body 236
classes of 234-237
clearances for 225
effect of bad grinding of . . . 225, 226
flat chucking 136, 138
four-groove ^ 250, 251
hand method of grinding twist,
225, 226, 228, 229
high-speed steel 225, 231, 232
machine method of grinding
twist 227, 228
oil I 257-259
pin or wire 237
reamer 237
round-shank, flat 232
speeds and feeds for 237-241
straight and taper-shank twist 230
straight-groove 233
tables of speeds and feeds for
carbon-steel 237, 238
table of speeds and feeds for
high-speed steel 239
tap 237
taper-shank twist 230-232
thinning the point of twist ... 226
three-groove 136, 250, 251
twist 225-259
Drills twisted from flat bar, twist. . 231, 232
Drills for brass, grinding twist ...... 232
Drills without stopping machine,
changing 252, 253
Driving fits 70, 100
lathe work 20, 21
Duplicate pieces, schedule of opera-
tions for making 54
Duplicating sizes, lathe stops for .... '3
382
INDEX
Page
Eccentric center fixtures 340, 341
turning 338-343
Eccentric, turning engine 339, 340
Eccentric shaft, turning 338, 339
Elastic grinding wheels 200
Electrical units 346
Electrically-driven engine lathe 10
machine tools. ... 9, 10
Emery cloth for polishing, order of
applying 160, 161
Emery wheels 198-202
Emery wheels, diamond tool for tru-
ing 204
End-measuring rods 78
Engine lathe 1-7
Engine-lathe countershaft 2-4
gear headstock 313, 314
headstock 2-5
Engine lathe with rapid system of
change gears .... 8, 9
work 54-60
Engine lathe, hand reaming in 142, 143
power reaming in. . .143-145
tapping in 312, 313
English standard (Whitworth) threads.
102, 119, 120
Expanding mandrels 147, 153
Expansion bolts 285, 290
of work while grinding . 207, 208
turning. ... 58
Extension for drill 255
springs '179
Face-plate chucks 130
Face plates, uses of 20, 21, 131-134
Face-plate work, lathe axis indicator
for 133, 134
Facing bar with inserted cutter 302
disk held in a chuck 127
small gear blank with double
holder and cutter 98
small gear blank with two
forged tools 96
Facing for bolts and screw heads,
spot 300
Feed for cylindrical grinding 203
vertical drilling machines,
hand and power,
222-224, 240, 241
Feed, cutting v 50
Fiber, machining hard rubber or 187
Files, mill 59, 60
Filing lathe work 59, 60
with round and half-
round files 60
Filing, speed for lathe 59, 60
Fillets of cast iron, scraping 154, 155
Fillister-head cap screws 288, 289, 300
Fillister-head stud cap screws 288
Finish facing cast iron 153
grinding 207
of work by grinding 207
reaming 139
square 33, 34
squaring cast iron 33, 34, 96
steel or wrought
iron 87, 88, 96
with side tool 33, 34
graver 166
threading with a tap 312, 313
Page
Finish turning 28
cast iron 36, 37
cast iron, large square-
nose tool for 37
cast iron, round-nose
tool for 36, 37
cast iron, small square-
nose tool for 37
steel or wrought iron . . 90-92
with a graver 165-167
Finished bolts and nuts,
124, 125, 283, 350, 351
Finishing cut 28
Fits in machine construction 68
Fits, classes of 68
driving 70
forcing 71-74
grinding 76, 209-215
holes for 75, 76
press for forcing 72-74
pressure and allowance for run-
ning 68, 69
producing standard 76
schedule of operations for grind-
ing forcing 212, 213
schedule of operations for grind-
ing running 210, 211
schedule of operations for turn-
ing and filing drive 98, 99, 100
schedule of operations for turn-
ing and filing running 85, 86, 98, 99
shrinking 73, 75
sliding 70
table of driving 70
forcing 71
tables of running 69
shrinking 75
sliding 70
taper forcing 71
running 68, 85, 86
turning and filing 76
wringing 100
Fits with micrometer, producing
standard 76
Fitting, straight turning and 85, 86
Fixed nuts 337
Fixtures, eccentric center 340, 341
Flange drilling 260-264
jigs 261-264
Flange, clamping lathe carriage to
face large 152
finishing face and scraping
cast-iron (lathe work) 153-156
rough facing cast-iron 152
schedule of operations for
making cast-iron 154-156
scraping fillets of cast-iron . 1 54, 155
Flat chucking drills 136-138
fillister-head cap screws 288, 293
machine screws. 293-300
Flat drills, round shank 232
Flat-head cap screws 288, 300
machine screws . . . .293, 298, 300
Fluted chucking reamers 143, 144
Follower rests 193, 194
Footstock set-overs for turning
tapers, table of 365-367
Forcing fit? 71-74
press 72-74
Forgings, drilling 254-259
Forming tools 29, 95, 190, 191
Formulas for bolt heads and nuts
303, 350, 351
INDEX
383
Page
Formulas for International and French
standard threads .... 347
metric threads 347
Sharp V-threads 105
Square threads 315, 316
Twenty-nine degree
threads 326
United States standard
threads 106, 107
Whitworth (English)
standard threads .. 1 1 9, 120
Four-groove twist drills for drilling
cored holes 250, 251
Fractional threads 114-117
Frames, drilling machine 243-251, 260
Gage for grinding and setting Twenty-
nine degree thread tools 328-330
Gage sizes for United States standard
sheet and plate steel and iron 376
Gage, American Screw Company's
machine-screw 298
center 15
Sharp V-thread 15, 108
Square threading tool angle . . 317
twist drill grinding 229
United States standard thread 109
Gage sizes, decimal equivalents of dif-
ferent steel music wire 375
Gage sizes in general use, different
wire 373
Gages, caliper 77
end-measuring rod 78
hole 77-79
limit '...78, 79
numbered drill 235, 236
reference lisks 78
special 79
standard cylindrical-plug and
ring 77
standard and limit 77-79
twist-drill 234-236
wire 234-236
Gear headstock, engine-lathe 313, 314
Gears, change 2, 3, 110-112, 115-117
Glass, drilling 52
Graver 164-167
Graver, finish squaring with 166
finish turning with 165-167
grinding 42
rough squaring with 166
rough turning with 165, 166
Grinder, automatic sizing 218, 219
universal tool 43, 44
wet-tool 42-44
Grinding boring tool 43
cast-iron roll 216, 217
cutting-off tool 40, 41
diamond-point tool 40, 43
fits 76, 209-215
graver 42
high-speed steel cutter 42
lathe centers 17
machine centers, 195-197, 204-206
phosphor-bronze taper bush-
ing 221
round-nose hand tools 43
round-nose tools 37, 38
side tool 38, 39, 43, 44
slender shaft 217, 218
square threading tools 40, 41
Page
Grinding straight and taper on one
piece 219, 220
taper collet 220
tapers 213-215, 219-221
to shoulder 215
Twenty-nine degree thread-
ing tools 328-330
twist drills for brass 232
United States standard or
Sharp V threading tools.. 41, 42
with back rests 217-219
Grinding, allowances for 207
cylindrical 195-221
^ depth of cuts for 203
direction of rotation of
work and wheel for 203
expansion of work while . 207, 208
feed for cylindrical 203
lubricants for 207
machine 195-221
measuring tools for 208
methods of driving work
for 205, 206
rough and finish 207
setting swivel table for
straight 206
setting swivel table for
taper 206
speed of work for 203
the finish of work by 2#7
wet and dry 206-208
width of face of wheel for. . 203
Grinding drills, hand method of. .228, 229
machine method of 227, 228
Grinding forcing fits, schedule of
operations for 212, 213
Grinding on two dead centers, prin-
ciple of 195
Grinding machine, universal 196, 197
^ universal and tool,
211, 212
Grinding machines, care of 208
classes of.. 196
operating universal 209
plain 215-220
truing centers of,
204, 205
Grinding of drills, effect of good and
bad 225, 226
Grinding running fits, schedule of
operations for 210, 211
Grinding standard mandrel, schedule
of operations for 213-215
Grinding tapers, method of 206
Grinding wheels 198-202
Grinding wheels, alundum 198-202
carborundum 198-202
celluloid 198, 200
chart of 199
combination 200
corundum 198-202
elastic 200, 201
emery 198-202
grades of 198, 201
mounting of 202
selection of .201, 202
shapes of 199, 201
silicate 194 200
table of speeds for.. 202
tanite 198, 200
truing 203, 204
vitrified 198, 199
vulcanite 198, 200
384
INDEX
Grinding work of one diameter, end-
driving dog for 205, 206
Ground work, seasoning of 208
Grooved dead center for squaring.. .33, 34
Guards, water 207, 209, 210
H
Half diamond-point tools 93
Hammer, lead 148
machinists' ... 23, 24
rawhide 148
Hammers for finished work, soft 148
Hand chasers 173, 174
cutting-off tools 177, 178
nurling 188
reamers 139-143
reaming in engine lathe 142, 143
reaming stand.. .141, 142
vertical drilling
machine 141
reaming in vise 140
tapping 269-279, 293, 294
threading 279-281, 294, 295
turning 164-179
machine handle 167-170
tools for brass finishing 174-176
Hand taps, set of 269, 270
turning, templets for 167, 168
tools, clearance of 164
cutting speeds for 164
graver. . . . , 164-166
round-nose 166, 167
Hand tools from old files, making. . 178, 179
Handles, machine 167-170
Hanger bolts 290
Headless bolts 285
screws. See Set Screws.
Height of lathe cutting tools. .27-37, 87-97
Hexagonal head bolt 282, 283
cap screws . . 287, 288, 300
Hexagonal, calculating diameter to
turn blank for milling or filing. . . . 303
High-speed steel drills 225, 231, 232
lathe tools 28, 90,91, 93, 95
High-speed steel drills, speeds for. . . 239
High-speed steel lathe tools, cutting
speeds for
Holders and cutters, lathe,
93-96, 310-312, 318
Hole gages 77-79
Hole diameters, table of limits of 75, 76
Holes, allowances for reamed, ground
and bored 75, 76
counterbored 300
countersunk,
19-21, 24, 25, 300,302, 303
depth of tapped 272, 273
reamed.. 139-145, 236, 237, 242-247
table of allowances and limits
for standard 70
tapped,
171, 172, 236, 237, 246-248,
273-279, 296-299
Hollow oil drill for deep drilling 259
Hollow shafting, method of drilling . . 259
Hot centers, burnt or 56
Hot pressed nuts 285
Improvised bolts 283, 284
Independent chucks 127
Independent chucks, to true and hold
work in 127
.49
Indexing in the engine lathe 304
Indicator, axis 133, 134
surface speed attachment
for speed 48. 49
Indicators, dial 344
lathe '.."" 343
T ., ,. test 343
Inside calipers 305, 306
Inside calipers, measuring with . . . 305, 306
setting 305
Inside micrometer calipers, large. .307, 308
small.. 306, 307
Inside micrometer calipers, to meas-
ure with 306-308
Inside micrometer calipers, reading, 306-308
Square threading tools 29, 95,319, 320
Square threading tools, setting. 319
squaring tool, squaring with, 309, 310
threading or screw cutting
tools, setting United States
standard or Sharp V 311
Inside threading or screw cutting
tools, United States standard or
Sharp V 29, 95, 310, 311
Inside turning or boring in the speed
lathe ns
Inside Twenty-nine degree threading
_ tools. 95, 329, 330
Inside United States standard or
Sharp V threading in the engine
T lathe 310-314
Interchangeable machine parts 260
International and French standard
threads 347
Interrupted thread tap 313
Iron wire 373, 377
Iron, lathe cutting tools for cast. . . .27-37
lathe tools for steel or wrought . 87-98
Jarno tapers 363, 364
Jig vise 267, 268
Jig, solid 260, 269
Jigs for tapping 265, 275
Jigs, box 263-265
classes of drilling 260
drilling 260-269
example of improvised 260, 261
multiple 260
plate (flange) 261, 262
rotary 260
Joule 346
Journals. See Bearings.
K
Kerosene for machining aluminium . . 51
Keys, drill drifts or center. . . 230, 231, 233
Knurling. See Nurling.
Lag screws 289, 290
Lands of reamers 139
taps 270
Lard oil 50, 51
Lathe apron 5-7
back gears 2-5
box for tools 53, 55
carriage 1-3
centers 1, 2, 3, 16-18
cross feed 5-7
dogs or drivers 20
holders and cutters,
93-96, 310-312,318
INDEX
385
Page
Lathe test indicators 343
long, feed 57
mandrels 146-153
revolutions 48, 49
stops for duplicating sizes 8
tools for cast iron 27-37
steel or wrought iron
29, 87-98
with rapid change-gear mecha-
nism 8, 9
Lathe, electrically driven engine 10
engine 1-7
speed 11, 12
Lathe centers, grinding 17
mounting work on,
20, 21,54-56
truing engine 16, 17
truing speed 15-18
Lathe tools, chart of forged 28, 29
clearance of 27, 28
cutting angles of 27, 28
cutting speeds of 47-50
height of 30, 35, 36
high-speed steel,
28, 90, 91, 93-95
rake of 27, 28
Lathe work, axis indicator for 133, 134
center holes in 19-26
filing 59, 60
Lathes, attachments for,
8, 17, 84, 85, 192, 194
classes of 7
requirements for successful
use of engine 15
swing of i 7
Laying out two-throw 90 D crankshaft
center fixtures 340, 341
Laying out holes in engine crank. .132, 133
work for drilling,
242-244, 246-250
L8ad hammer 148
Lead holes 253, 254
of screw threads 104, 117
screws 2, 3, 6, 7, 103
L8ad, machining 187
Left diamond-point tools 93
side tool 92
threads 114, 314
Leveling work on drilling table 255
Limit gages 78, 79
Line tapping. See Alinement drilling
and tapping.
Lining lathe centers 18, 19
Live center 2, 3, 16-18
Locating live center 4, 16
Lock or check nuts 285, 286
Long, feed, lathe 5-7
Lubricants for cutting tools 50-52
grinding 207
Lubricating or oiling bearings 13
- M .:-":
Machine grinding 195-221
nurling 189
oil 13
Machine, centering 25, 26
Machine handle, schedule of opera-
tions for mak-
ing a 168-170
Machine parts, interchangeable 260
Machine screw bolt 293
dies 294, 295
sets 351
Page
Machine screw taps 293, 294
Machine screws 292, 293, 295-299, 368
Machine screws, A. S. M. E. stand-
ard and special 295, 297
American Screw Com-
pany's 297, 298,368
flat-head 293
fillister-head 293
oval countersunk
head 293
round-head 293
Machinists' hammer 23, 24
Machines, care of 53
Mandrel block 148
or arbor press 74, 148, 149
Mandrel, schedule of operations for
making standard 149-152
schedule of operations for
grinding standard 213-215
soft hammers for driving. . . 148
Mandrel dimensions, standard. . .369, 370
Mandrel into work with a press, forc-
' ing 148, 149
Mandrels or arbors 146-154
Mandrels or arbors, built-up and special,
bridges in hollow
castings to take
place of 147
center 149
expanding. ... 147, 153
lathe 146-153
nut 122
standard solid,
146, 369, 370
Master taps 271
Material (stock) , inspection and meas-
urement of 52
Measuring with spring calipers 45-47
thread calipers 104
work with inside calipers,
305, 306
micrometer cali-
pers 61-63
outside calipers 45-47
vernier calipers, 65, 66
Metal to wood, fastening ~29i
Meter, cut 48
Metric threads 102, 117, 345
Micrometer caliper, ten-thousandth. . 67
Micrometer calipers, large inside. .307, 308
measuring with, 61-64
measuring with
inside 306-308
reading 61, 62
small inside.. 306, 307
Micrometer principle 61
Mill files 59, 60
Milk for machining copper 51
Morse tapers 359, 360
Mounting work on lathe centers,
20, 21, 54-56
Multiple jigs 260
Multiple-spindle drilling machines
262-264, 268, 269
Multiple threads 335, 336
Multiple-threaded taps 338
Music wire gage sizes in decimals of
an inch, table of different steel. . . . 375
Numbered drill gages 235, 236
Nurling tools 188, 189
386
INDEX
Page
Nurling, hand 188
machine 189
Nurled head screws. . 183-186, 188, 189, 292
Nut and bolt making 121-125
mandrels 122
taps 271
Nut, fitting Square thread screw to. . 325
fitting Twenty-nine degree thread
screw to 332, 333
fitting United States standard
or Sharp V thread screw to. 114, 125
making Square thread 323-325
Twenty-nine degree thread. . . 333-335
Nut in alinement, drilling and tap-
ping a cross feed 337, 338
Nuts, automobile standard screws
and 286, 348, 349
bracket 337
bushing 337
castle 286, 348, 349
clamp 123
cold punched 285
description of 285
fixed 337
hot pressed 285
iock or check 285, 286
planer 284
threading,
102-120, 173, 174, 183, 185,
186, 269-279, 292-294, 310, 338
thumb 292
wing 292
Ohm -. 346
Oil, kerosene 51
lard 50,51
lubricating 13
sperm 50
Oil drills for deep drilling 257-259
Oiling bearings
ways of a machine 13
Oil stones, Arkansas 44
India 44
Oilstoning tools 44
Order of operations. See Schedule of
operations.
Operations. See Schedule of opera-
tions.
Oval countersunk-head cap screws. . 288, 300
countersunk-head machine
screws 293, 300
fillister-head cap screws 288, 300
head machine screws. 293, 300
Pin or'wire drills 237
Pin, split 286, 348, 349
Pins, dowel 289
taper 144, 145
Pipe tap, threading 119
Pipe turning, revolving dead center
for 147
Pitch of threads 104
Plain grinding machines 215-220
Planer nuts 284
Planer head bolts 283, 284
Planisher, turning brass with 175, 176
Plate jigs 261, 262
Plate and wire gages, uses of different 377
Plate steel and iron gage sizes, United
States standard sheet and 376
Polishing brass 162, 163
Page
Polishing cast-iron flange 1 60, 161
copper 162, 163
clamps 162
steel shaft 162
Polishing, abrasives, speeds, and ma-
chines to use for 160
order of applying emery
cloth for 160, 161
Power reaming in engine lathe. . . . 143-145
tapping 266, 267, 277
threading 280
Press fits. See Forcing fits.
Press, forcing 72, 74
mandrel or arbor 148, 149
Pulley taps 271
Pulley, chucking 137, 138
schedule of operations for mak-
ing 158-160
Pulleys, locating set screws for. . . . 158-160
tapering or crowning 156-159
Punch, center 23, 24
Radial drilling machines 265-268
Rake of lathe tools 27, 28
Rawhide hammer 148
Rawhide, machining 187
Reading inside micrometer calipers, 306-308
vernier calipers 66
Reading micrometer calipers 61, 62
vernier calipers 65. 67
Reamed holes. .139-145, 236, 237, 242-247
Reamer drills 237
Reamers, adjustable 141, 142
broach 144, 145
center 23, 24
clearance of 139
flat chucking 137
fluted chucking 143, 144
fluted taper pin 144, 145
hand 139-143
irregularly spaced teeth on 139
lands of , 139
rose chucking 144
Reaming taper holes in a speed lathe
by power 144, 145
Reaming, allowances for 139
finish 139
rough 139
Reaming in engine lathe, hand 142, 143
power 143-145
Reaming in reaming stand, hand. . 141, 142
Reaming in vertical drilling machine,
hand 141
Reaming in vise, hand 140
Reference disks 78
Rests, follower 193, 194
steady 191-193
Revolutions of lathe 48, 49
Ripper, rough turning brass with a, 174, 175
Rolled threads 103
Rotary jigs 260
Rough bolts and nuts 283, 350, 351
drilling 243
grinding 207
reaming 139
squaring 33
cast iron 31
steel or wrought
iron 87, 88
with graver 166
with side tool, 33, 34, 87, 88
turning 28
INDEX
387
Page
Rough turning cast iron 36
steel or wrought iron . 88-90
with graver 165, 166
Roughed-up bearings, treatment of . . 13
Roughing cut 28
Roughing tool, large 89, 90
small 29, 89
Round-head cap screws 288, 300
machine screws 293, 300
Round-nose tools 31, 32, 36
for brass 182, 183
hand tools 166, 167
Round-nose tools, grinding 37, 38
Rubber or fiber, machining hard 187
Rules, shrink 355
standard steel 45, 305
Running fits 68, 69, 85, 86
Running fits, schedule of operations
for turning and filing 85, 86, 98, 99
Rust on machines, to prevent 13
Schedule of operations for centering,
squaring and straight turning 57-59
Schedule of operations for chucking
with a flat drill and chucking ream-
er in an engine lathe 137, 138
Schedule of operations for cutting
double Square thread 336
Schedule of operations for drilling and
tapping a cross-feed screw nut in ax-
ial alinement in a milling machine
saddle and knee 337, 338
Schedule of operations for drilling,
reaming and tapping 246, 247
Schedule of operations for grinding
forcing fits 212, 213
Schedule of operations for grinding
running fits 210, 211
Schedule of operations for grinding
standard mandrel .. . .213-215
Schedule of operations for laying out
and turning eccentric shaft 338, 339
Schedule of operations for laying out
two-throw 90 crankshaft center
fixtures 340, 341
Schedule of operations for making
brass binding post 183-187
Schedule of operations for making
brass nurled thumb nuts 185-187
Schedule of operations for making
cast-iron flange 154-156
Schedule of operations for making
duplicate pieces 54
Schedule of operations for making
finished bolt and nut 124, 125
Schedule of operations for making
machine handle 168-170
Schedule of operations for making
pulley 158-160
Schedule of operations for making
Square-thread nut 323-325
Schedule of operations for making
Square-thread screw 320-322
Schedule of operations for making
standard mandrel 149-152
Schedule of operations for making
Twenty-nine degree thread screw. 331-333
Schedule of operations for making
Twenty-nine degree thread nut . 333-335
Schedule of operations for straight
turning and fitting 85, 86
Page
Schedule of operations for turning
and filing drive fits. See Shaft
blank 98, 99, 100
Schedule of operations for turning and
filing running fits 98, 99
Schedule of operations for turning and
fitting a taper 82, 83
Schedule of operations for turning
crankshaft 342, 343
Schedule of operations for turning
engine eccentric 339, 340
Schedule of operations for United
States standard or Sharp V inside
threading in the engine lathe. . ..311, 312
Schedule of operations for United
States standard or Sharp V threading
in the engine lathe 112-114
Schedule of operations for preparing
two shaft blanks for fitting, mul-
tiple 98, 99
Scraping fillets of cast iron (lathe
work) 154, 155
radial faces of cast iron
(lathe work) 153
Screw bolts, machine 293
Screw cutting. See Threading.
Screw cutting in the engine lathe,
110-119, 124, 125
on taper work. 119
with rapid change-gear
mechanism 8, 9
Screw cutting, catching the thread in 1 18
calculating simple gear-
ing for 110, 111
description of mecha-
nism for 111-113
lathe tools for,
95, 107-109,310-320,
328-330
operating lathe for. . 112, 113
preparation of blank
and nut for Ill
setting United States
standard or Sharp
V tool for 108
Screw cutting, theory of 110, 111
Screw cutting in an engine lathe,
inside United States standard or
Sharp V 310-314
Screw cutting tools, inside United
States standard or Sharp V, 95, 310, 311
Screw cutting tools, to set inside
United States standard or Sharp V . 311
Screw dies, machine 294, 295
gage, American Screw Com-
pany's machine 298
Screw heads, counterboring for. . .299-303
countersinking for. . 302, 303
Screw heads and bolts, spot facing
for 300
Screw sets 351
Screw thread calipers . 104
Screw thread to a shoulder in an
engine lathe, cutting an inside. ... 314
Screw threads. See Threads.
102-125, 269-299,
310-338, 347-354
per inch 104, 105
Screw threads, calculating compound
gearing for 115, 116
calculating gearing to
cut fractional.... 114-1 17
388
INDEX
Page
Screw-threads, calculating simple gear-
ing for 110-113
counting 104, 105, 113
fractional 114-117
French standard 347
International stand-
ard 347
multiple 335, 336
pitch of 104
right and left 103
rolled 103
Sharp V. . 102-125, 310-314
Square' 314-325
Twenty-nine degree.325-335
United States standard
102, 106-109,
111-113, 124, 125
uses of different 103
Whitworth (English)
standard. . . 102, 119, 120
Screw threads with an English lead
screw, calculating gearing for cut-
ting metric 117
Screw threaded work, root diameter
of 102, 104
Screws and nuts, automobile standard
286, 348, 349
methods of thread-
ing 103
Screws, cap 287, 288, 300
collar cap 288
examples of drilling, counter- ,
boring, and countersinking
for machine or cap 300
fillister-head 288, 289, 293, 300
flat-head 288, 293, 298, 300
hexagonal-head 287, 288, 300
lag 289, 290
lead 2, 3, 6, 7, 103
machine. . . .292, 293, 295-299, 363
multiple-thread 335, 336
nurled-head. 183-186, 188, 189, 292
oval countersunk head, 288, 293, 300
round-head 288, 293, 300
set 291, 292
Sharp V thread ..102-125, 310-314
Square-head 248, 288
thread 314-325
thumb 292
Twenty-nine degree thread, 325-335
United States standard thread,
102, 106, 107, 109, 111-113,
124, 125
wood 290, 291
Screws and stud bolts, drilling for,
248, 249, 260-269, 300
Seasoning of ground work 208
Semi-finished bolts and nuts,
124, 125, 283, 284, 350, 351
Set-overs for turning tapers, table of
footstock 365-367
Sets, machine screw 351
Set screw chucks. . . : 232, 255
Set screws, cone-point 291, 292
cup-point 291, 292
drilling for. . . 158-160, 247-250
hanger pivot-point. . . .291, 292
headless 291, 292
round-point 291, 292
uses of 291, 292
Set screws for pulleys, locating . . . 158-160
Setting dead center in alinement. ... 18, 19
inside calipers 305
Page
Setting inside Square threading tool 319
Twenty-nine degree
threading tool 330
United States stand-
ard and Sharp V
screw threading
tools 311
outside calipers 45
Square threading tools 318
studs by hand 284
power 266, 267
Twenty-nine degree threading
tools 329
United States standard or
Sharp V tools for threading 108
Shaft, polishing 162
grinding a slender 217, 218
turning a slender 192, 193, 194
Shaft blanks for grinding fits, sched-
ule of operations for preparing. ... 98, 99
Shaft blanks for turning and filing
fits, schedule of operations for pre-
paring. 99-101
Shafting, rods and bolts, straightening 26
Sharpening dies 280
taps 271
Shear tools 92
Sheet and plate, steel and iron gage
sizes, United States standard 376
Sheet metal, grinding twist drill for. . 232
twist drills for 232, 233
Shoulders, squaring 34, 121, 309, 310
Shrink rules 355
Shrinking fits 73, 75
Shrinkage of castings 354
Side tool, left 92
tools 29, 32-34, 87, 88, 92, 94, 95
tools, grinding 38-40
Silicate grinding wheels 200
Sizes of taps 269
Slender shaft, grinding 217, 218
Slide rest for speed lathe 179
Sliding fits 70
Sliding fits, table of 70
Slotting by drilling 253
Soap mixture for cutting tools 51
Soda water for cutting tools 51
Soft hammers for driving mandrel. . . 148
Solid jig 260, 269
Speed for lathe filing 59, 60
of work for grinding 203
Speed indicator, surface speed attach-
ment for 48, 49
Speed, number of revolutions to ob-
tain surface 371, 372
Speed lathe 11, 12
countershaft 11, 12
Speed lathe, chucking in 170, 171
drilling in 255-257
methods of holding work
in 164
slide rest for 179
spindle speeds for 239-241
tapping in 171, 172
Tee-rest for 11, 12, 164
Speeds of drilling machines, 222-224,239-241
gear-driven vertical drilling
machine 241
high-speed steel drills 239
Speeds for grinding wheels 202
hand tools, cutting 164
lathe tools, cutting 47-50
Sperm oil 50
INDEX
r 389
Page
Split pin 286, 348
Spot facing for heads of bolts and
screws 300
Spring calipers 45-47
chuck 130, 294, 295
cotter 286, 348, 349
tools 91, 92
winding in engine lathe. . . .179-181
Spring, extension 179
Spring winder, winding springs with 180
Springs, coil 179, 181
compression 179
Square dog 121
Square-head bolt 248, 283
cap screws 248, 288
Square-nose tools 37
Square, calculating diameter to turn
blank for milling or filing 303
Squaring to shoulder 34, 121, 309, 310
with hand tools 166
with inside squaring tool,. 309, 310
with graver 166
Squaring, removing burr when 33, 34
rough 33
step method of 87, 88, 166
two forged tools for 96
Squaring cast iron, round-nose tool
for 31
Squaring cast iron, side tools for,
29, 32-34, 87, 94, 95
Squaring steel, side tools for, 87, 88, 92, 94, 95
Square thread taps 320
Square thread nut, fitting screw to. . 325
schedule of opera-
tions for mak-
ing 323-325
Square thread screw, schedule of
operations for making a 320-322
Square thread screw and nut, sectional
view of 315
Square threading tool angle gage .... 317
holders and
cutters. . . .95, 318
Square threading tool, setting inside. 319
setting 318
Square threading tools 29, 95, 315-318
Square threading tools, inside
29, 95, 319, 320
grinding. . . .40, 41
Square threads 314-325
Square threads, formulas for 315, 316
width and inclination
of tool for mul-
tiple 336
Squares, caliper 66, 67
Standard cylindrical plug and ring
gages 77
Standard and limit gages 77-79
holes 75, 76
solid mandrels or arbors,
146, 351-358, 369, 370
Steady rests 191-193
Steady rests, turning shaft supported
with 192
Step method of squaring 87, 88, 166
with hand
tools in speed lathe 166
Steel wire 373-375, 377
Steel, twist drills for drilling hard. 231, 232
Steel rules, standard 45, 305
Steel or wrought iron, diamond-point
tool for finish turning 90-92
Page
Steel or wrought iron, diamond-point
tool for rough turning 88
Steel or wrought iron, drilling 230, 231
finish squaring,
87, 88, 96
turning,
90, 91, 92
lathe tools for,
29, 87-98
rough squaring, 87, 88
turning, 88-90
Stock, cutting off 97, 98
Stock (material) , inspection and meas-
urement of 52
Stove bolts 354
Straight-groove drills 233
shank twist drills 230
Straight grinding, setting swivel
table for 208
Straight turning and fitting, schedule
of operations for 85, 86
Straightening shafting, rods and bolts 26
Stubs' steel wire gage sizes 374, 377
iron wire gage sizes 373, 377
Stud bolts 266, 267, 283, 284
holder 284
Studs for driving large work 149
Studs by hand, setting 284
power, setting 266, 267
Stud bolts and screws, drilling for,
248, 249, 264-267, 268, 284
Surface speed attachment for speed
indicator 48, 49
Surface speed, table of number of
revolutions required
to obtain 371, 372
Swing of lathes 7
Table and formulas for bolt heads
and nuts 303, 350, 351
Table center 256
of allowances and limits for
standard holesTT 76
automobile standard screws
and nuts ..348, 349
Brown & Sharpe tapers. .361, 362
center-hole dimensions . 21
common fractions and deci-
mal equivalents 64
decimal equivalents of dif-
ferent steel music wire
gage sizes 375
decimal equivalents of Stubs'
steel wire 374
driving fits 70
estimated weight of core
prints and cores for cast-
ings 354
forcing fits 71
footstock set-overs for turn-
ing tapers 365-367
frades of grinding wheels. 198, 201
nternational and French
standard threads 347
Jarno tapers 363, 364
lathe cutting speeds 49
limits of hole diameters .... 76
lubricants for cutting tools. 51
Morse tapers 359, 360
number of revolutions re-
quired to obtain surface
371,372
390
INDEX
Table of Sharp V screw threads 106
Sharp V-thread taps S Q 5 * and
smaller 299
shrinkage of castings 349
sliding fits 70
speeds for grinding wheels . . 202
and feeds for carbon
steel drills 237-239
speeds and feeds for high-
speed steel drills 239
spindle speeds for belt-driven
vertical drilling machine 239-241
spindle speeds for speed
lathe 239-241
spindle speeds for a high-
speed vertical drilling ma-
chine 241
Square threads 316
standard mandrel dimen-
sions 364, 365
thread parts of Twenty-nine
degree threads 327
Twenty-nine degree threads 328
United States standard bolts
and nuts 348
United States standard Sharp
V thread taps and tap
drill sizes 278, 279
United States standard sheet
and plate steel and iron
gage size 371
United States standard screw
threads 107
weight of castings from
wooden patterns 349
Whitworth (English) stand-
ard threads 120
Tables of A. S. M. E. standard and
special machine screws,
taps, and tap drill
sizes 296, 297
decimal equivalents of
American Screw Com-
pany's machine screws,
taps, and tap drill
sizes 298, 363
different drill sizes, con-
secutive and compara-
tive 350-353
different wire gages in gen-
eral use, comparative. . . 368
gage sizes of twist drills. .234-236
running fits 68, &9
shrinking fits 75
Tanite grinding wheels 198, 200
Tap bolts 288
drill diameters (how obtained) . . 278
drills 237
holes 272, 273
wrenches 271-274, 277
Tap, interrupted thread 313
to finish thread backing plate
with- 312-314
Tap cut large, making a 276
Tap wrench, single-end 272
Taper forcing fits 71-74
pm 144, 145
running fits 68
shank twist drills 230-232
turning 80-86
with foot stock set-over 81, 83
with taper attachment 84, 85
Page
Taper, schedule of operations for turn-
ing and fitting a 82, 83
Taper attachment, using 84, 85
bushing, grinding 221
collet, grinding 220
Taper grinding, setting swivel table
for 206
Taper holes in a speed lathe by power,
reaming 144, 145
Taper pin reamers, fluted 144, 145
Taper work, setting tool to thread. . . 119
Tapering or crowning pulleys 156-159
Tapers, Brown & Sharpe 356, 357
calculating distance to set
over footstock for 81, 82
grinding 213-215, 219-221
Jarno 358, 359
methods of grinding 206
Morse 354, 355
standard and special 80
table of footstock set-overs
for turning 360-362
use of patterns to obtain 82
Tapers are expressed, how 80
Tapped holes,
171, 172, 236, 237, 246-248,
273-279, 296-299
Tapped holes, depth of 272, 273
Tapping attachment 266, 267
backing plates of chucks. .312, 313
by hand in vertical drilling
machine 274, 275
for cap screws 247, 249
in engine lathe 312, 313
in speed lathe 171, 172
loose nuts 272, 273
with machine screw tap. ... 294
Tapping, accurate hand 274, 275
alinement drilling and. . . 337, 338
approximate 273, 274
hand 269-279, 293, 294
jigs for 265, 275
power 266, 267, 277
Taps 269-279, 293, 294
Taps, adjustable 271, 313
automatic 271
clearance of , 271
lands of 270
master 271
machine-screw 293, 294
multiple-threaded 336
nut.. 271
pulley 271
removing broken 276, 277
set of hand 270
sharpening 271
sizes of 269
Square thread 320
threading pipe 119
Twenty-nine degree thread . . . 330
Taps and tap drill sizes of American
Screw Company's machine screws. 298
Taps and tap drill sizes of A. S. M. E.
standard machine screws 296, 297
Taps and tap drill sizes of Sharp-V
threads 278, 279
Taps and tap drill sizes of United
States standard threads 278, 279
Taps in binary fractions, small 299
Templets 167, 168
Ten-thousandth micrometer caliper, 67
Test indicator, dial 344
INDEX
391
Test indicators, lathe 343
Testing angle of centers 15
axial truth of center punch
marks with indicator. . . 133, 134
Thread calipers 104
Thread, cutting Square 314-325
cutting Sharp V.. 110-1 17, 310-314
cutting United States stand-
ard 110-117, 310-314
gage for Sharp V 108
lead of 104, 117
Twenty-nine degree 325-335
Thread gage, grinding tools to fit
United States standard 109
Thread screw to nut, fitting Square . 325
fitting Twenty-
nine degree,
332, 333
Thread screw to nut, fitting United
States standard or Sharp V 114, 125
Thread to a shoulder in an engine
lathe, cutting an inside screw 314
Threaded work, diameter of. . 102, 104, 111
root diameter of. . 102, 104
Threading, 102- 120, 124, 125, 172-174,
279-281, 294, 295. 326-336
catching the thread in 118
dies 279-281, 294,
in engine lathe,
110-119, 124, 125
in speed lathe 172, 173
nuts,102-120, 173, 174, 183,
185, 186, 269-279, 292-
294, 310, 338
taper work 119
tool gage for grinding and
setting Twenty-nine de-
gree thread tool 329, 330
tool holders and cutters,
94,95, 318
tools for United States
standard or Sharp V
thread 29, 95, 107-109
with machine screw di'es, 294, 295
rapid change-gear mechan-
ism 8, 9
Threading, calculating compound
gearing for 115, 116
calculating simple gear-
ing for 110, 111
description of mechanism
for 111-113
hand 279-281, 294, 295
lathe tools for,
95,107-109, 310-320, 328-330
operating lathe for. .. 112, 113
power 280
preparation of blank and
nut for Ill
setting United States
standard or Sharp V
tool for 108
theory of 110, 111
Threading in the engine lathe, inside,
United States standard or Sharp V, 3 1 0-3 1 4
Threading to a shoulder, inside 314
Threading tool, angle gage for Square 317
Threading tools, 29, 94, 95, 107-109,
310-320, 328-330
Threading tools, inside Square 29,95, 319,320
inside United States
standard or Sharp
V 95, 310, 311
Pace
Threading tools, making Square .... 317
multiple 336
setting inside United
States standard or
Sharp V 311
setting inside Square 319
setting inside Twen-
ty-nine degree... 330
Threading inside setting United States
standard or Sharp
V 108
Square.... 29.95, 315-318
Twenty-nine degree,
29, 95, 326, 328, 329
United States stand-
ard or Sharp V,
29, 94, 95, 107-109
United States stand-
ard or Sharp V in-
side screw. .95, 310, 311
Whitworth (English)
standard 120
Thre,ads,102-125,269-299, 310-338,347-354
per inch 104, 105
Threads, British Association standard, 102
calculating compound gear-
ing for 115, 116
calculating gearing for given
lead of 104, 117
calculating gearing to cut
fractional 114-117
counting 104, 105, 1 13
double 335, 336
fractional 114-117
French standard 347
International standard .... 347
left 114, 314
metric 102, 117, 345
multiple 335, 336
pitch of 104
right and left 103
rolled 103
screw,
102-125,269-299,310-338,
347-354
Sharp V 102-125. 310-314
Square 314-325
Twenty-nine degree 325-335
United States standard,
102,106, 109,111-113,124,
125, 310-3H
uses of different 103
Whitworth (English) stand-
ard 102, 119, 120
Threads with an English lead screw,
calculating gearing for cutting
metric screw 117
Three-groove twist drills for drilling
cored holes 250, 251
Thumb nuts 292
screws 292
Thumb nuts, schedule of operations
for making brass nurled 185-187
Time element 54
Tool holders and cutters, cutting off 93-95, 98
Tool holders and cutters, threading,
94, 95, 318
Tool holders, boring 95, 310
double 96
Tool holders and cutters
93-96, 98, 310-312, 318
Tools, boring- 29, 95, 308-310
chart of forged lathe 28. 29
392
INDEX
Page
Tools, Chattering of 91
forming 29, 95, 190, 191
half-diamond point 29, 93
hand 166, 167
height of lathe cutting. 27-37, 87-97
high-speed steel lathe,
28, 90, 91, 93-95
large roughing 29, 89, 90
lathe 27-44, 87-98
lathe box for 53, 55
lathe cutting-off . . .29, 94, 95, 97, 98
lathe threading,
29, 94, 95, 107-109, 310-320,
330-338
left diamond-point 93
nurling 188, 189
oilstoning 44
rake, clearance and cutting
angles of lathe cutting 27, 28
right and left, lathe 30
round-nose 31, 32, 36
shear 92
side 29, 32-34, 87, 94, 95
small finishing 90, 91
roughing 29, 89
spring 91, 92
square-nose 37
Square threading. . . 29, 95, 315-318
theory of cutting 27, 28
Twenty-nine degree threading,
29, 95, 326, 328, 329
Tools for cast iron, diamond-point. . . 34-37
lathe 27-37
Tools for steel or wrought iron, dia-
mond-point 88, 90, 91
Tools for steel or wrought iron,
lathe 29, 87-98
Tools made from old files, hand 178
Tools set at different heights, effect
of lathe 30, 35, 36
Tee rest for speed lathe 11, 12, 164
Truing engine-lathe centers 16, 17
grinding machine centers. .204, 205
wheels 203, 204
speed-lathe centers 18
Tube holes, cutter for drilling boiler,
254, 255
Turnbuckles 286
Turn to setting of outside calipers, ad-
justing tools to '. 46
Turning an engine eccentric 339, 340
a rod held in draw-in-chuck 130
a slender shaft 192, 193, 194
brass with a planisher 175, 176
bushing held in a chuck .... 1 28
crankshaft 342-343
steel or wrought iron with
large finishing tool 90, 91
steel or wrought iron with
large roughing tool 90
steel or wrought iron with
small roughing tool 89
steel or wrought iron with
small finiihin , tool 90, 91
taper 80-86
to a desired diameter 46
with graver 164-167
work of one diameter from
end to end 56, 57
Turning, curve 190, 191
eccentric 338-343
expansion of work while. . . 56
Page
Turning, finish 28
hand 164-177, 178
order of rough and finish ... 52
rough 28
shaft 338, 339
Turning brass with a ripper, rough 174, 175
Turning cast iron, diamond-point tool
for rough 36
round-nose tool for
finish 36,37
Turning cast iron, round-nose tool for
rough 31
Turning steel or wrought iron, dia-
mond-point tool for finish 90, 91
Turning steel or wrought iron, dia-
mond-point tool for rough 88
Turning steel or wrought iron, small
finishing tool for 90
Turning with taper attachment 84, 85
Turpentine for machining aluminium
or glass 51, 52
Twenty-nine degree thread taps 330
Twenty-nine degree thread nut, sche-
dule of operations for making. . . 333-335
Twenty-nine degree thread screw and
nut, sectional view of 325
Twenty-nine degree thread screw,
schedule of operations for mak-
ing 331-333
Twenty-nine degree threading tool
gage 329, 330
Twenty-nine degree threading tools,
29, 95, 326, 328, 329
Twenty-nine degree threading tools,
setting 329
Twenty-nine degree threading tools,
grinding 328-330
Twenty-nine degree inside threading
tools, setting 330
Twenty-nine degree threading tools,
inside 29, 95, 329, 330
Twenty-nine degree threads 325-335
Twenty-nine degree threads, formulas
for 326
Twist drill gages 234-236
grinder 227, 228
grinding gage 229
Twist drills 225-259
for brass 232, 233
cast iron
230-232, 234-237,250,251
hard steel 231, 232
steel and wrought iron,
230-232,234-237,257-259
thin sheet metal. . . 232, 233
made by twisting from
flat bar 231, 232
Twist drills, chucking with 135, 171
examples of good and
bad grinding 225, 226
gage sizes of 234-236, 355-358
hand method of grinding,
228,229
machine method of grind-
ing 227, 228
regular sizes of 234-237
straight-shank 230
taper-shank 230-232
Twist drills for brass, grinding 232
Twist drills for thin sheet metal,
grinding 232
INDEX
393
U Page
United States standard threading
tools, grinding 41, 42, 109
United States standard threads,
102, 106-109, 111-113, 124, 125, 310-314
United States standard thread gage, 109
or Sharp V inside threading tools
29, 95, 310, 311
United States standard or Sharp V
threading tools 29, 94, 95, 107-109
United States standard screw, sec-
tional view of 102, 107
Units, electrical 346
Universal chucks
grinding machine 196, 197
tool grinder 43,44
Universal chucks, truing and hold-
ing work in 128
Universal grinding machine, oper-
ating 209
Vaseline 13
Vernier calipers 65-67
principle 65
Vernier calipers, measuring with 66
reading 65, 66
reading inside 66
Vertical drilling machine described. 2 2 2-2 24
Vertical drilling machine, spindle speeds
for h i g fa-
speed 241
spindle speeds
for belt-
driven.. 239-241
Vertical drilling machines, hand and
power feed for 222-224, 240, 241
Vise, jig 267, 268
machinists' 281
Vitrified grinding wheels 198, 199, 201
Volt 346
Vulcanite grinding wheels 198, 200
Vulcanite, machining 187
V blocks 251
center 256
V thread, formulas for Sharp 105
V thread gage, Sharp. . 15, 108
Page
V thread screw, sectional views of
Sharp , 102, 105
threading tools, grinding 41, 42
V threads, Sharp 102-125, 310-314
W
Washers 285, 286, 290
Water for cutting tools, soda 51
grinding 206, 207
guards 207, 209, 210
Watt 344
Ways of a machine, oiling 13
Weight of castings from wooden pat-
terns 354
Weight of core prints and cores for
castings, estimated 354
Wet tool grinder 42-44
Wheels, grinding 198-202
Whitworth (English) standard thread-
ing tools 120
threads 102, 119, 120
Whitworth thread screw, sectional
view of 119
Winding springs 179-181
Wing nuts 292
Wire drills 237
gages . 234-236
Wire, brass 373, 377
copper 373, 377
cutting off 177, 178
iron 373, 377
steel 373-377
Wire and plate gages, uses of dif-
ferent 377
Wire gages in general use, compara-
tive tables of 373
Wrenches, tap 271-274, 270
Wringing fits 100
Wrought iron, lathe tools for steel or,
29, 87-98
Wood screws 290, 291
Wood, drilling 232
fastening metal to 291
Work, driving lathe . . . 777 20, 21
Zero lines 18, 27
SMITH BLUE-PRINT HOLDERS
AND TEXT-BOOK HOLDERS
FOR SHOP AND SCHOOL
AN IMPORTANT ADVANCEMENT IN THE
SCIENTIFIC MANAGEMENT OF TRADES, INDUSTRIES AND SCHOOLS
Saves Time
Convenient
location for
rapid read-
ing-
Increases
efficiency.
Unobstructe
v i e w .
Saves Blue Prints
Saves Eyesight
Reduces the
motions of
workmen.
A Law of Op-
tics obeyed;
perpendicular
line of vision.
Saves eyesight.
RIGHT WAY.
IMPROVED METHOD OF HOLDING BLUE PRINTS HOUNTED ON
SHEET METAL OR CARDBOARD.
Blue print cov-
ered with tools.
Soiled and
damaged
print
Slow reading
Obstructed view.
Slanting line
of vision
causes eye-
strain.
A Law of
Optics vio-
lated.
Ruins eyesight.
WRONG WAY.
OLD METHOD OF HOLDING BLUE PRINTS.
INDUSTRIAL EDUCATION BOOIi CO., Boston, U.S.Jt.
Holds mounted
or unmounted
prints, draw-
ings, tracings,
sketches,
or notes. Re-
volved to suit
position of work-
man.
Can be quickly
changed from
mounted to
unmounted
prints.
May be swiv-
elled, raised,
or lowered.
RIGHT WAY.
IMPROVED METHOD OF HOLDING UNflOUNTED BLUE PRINTS.
Workman must
turn around
to read draw-
ing.
Loss of time.
WRONG WAY.
CRUDE WAY OF HOLDING UNMOUNTED BLUE PRINTS.
Workman turns
round, picks
up print,
reads it,
lays it down,
turns back to
lathe.
Unhandy, incon-
venient loca-
tion.
Destructive
to prints.
Waste of time.
Inefficient.
WRONG WAY.
ANOTHER OLD WAY OF USING MOUNTED BLUE PRINTS.
Print soon be-
comes so soiled
that -it is
difficult to
read figures.
WRONG WAY.
ANOTHER OLD WAY OF USING UNMOUNTED BLUE PRINTS.
3
How to Operate Blue = print Holder to
Hold Mounted and Unmounted Prints.
Down!
Presto!
Up!
Lift the "Lift,"
insert print ;
lower "Lift,"
which se-
cures print,
as at "A."
Simple fixture.
INSERTING flOUNTED PRINT IN BLUE-PRINT HOLDER.
Lift the "Lift,"
insert top of
print, lower
"Lift."
Gravity of
"Lift" and
force of the " In-
clined Plane'
print as at
grips ^
Simplicity.
Rapidity.
Print not soiled
or torn.
No clips, no
springs, no
hooks, no repairs.
Nothing to get out
of order.
INSERTING UNMOUNTED PRINT IN BLUE-PRINT HOLDER.
4
Blueprint and Book Holder Combined.
Book held open
at proper angle
for reading.
Keeps book
clean.
May be swiv-
elled, raised,
and lowered
independently
or together.
A TEXT-BOOK HOLDER WITH TRANSPARENT CELLULOID COVER
TO PROTECT OPEN BOOK, AND BLUE-PRINT HOLDER
HOLDING MOUNTED PRINT.
Blue-print Holders and Book Holders may be used together or separately.
Brings the in-
formation
convenient to
the operation.
TEXT-BOOK HOLDER FASTENED TO BENCH AND HOLDING BOOK
OPEN, AND BLUE-PRINT HOLDER HOLDING MOUNTED PRINT.
How the Pages of a Book are Turned
in the Book Holder.
Simple!
Effective!
Rapid!
OPERATING BOOK HOLDER.
SWING HINGED, TRANSPARENT CELLULOID COVER BACK BY HANDLE
AT EITHER END OF HINGE AND TURN LEAVES OF TEXT-
BOOK, THEN SWING COVER ON TO BOOK.
Out of the way
and not lying
on bench
i
covered with
stock and tools.
BLUE-PRINT HOLDER ATTACHED TO PATTERN-MAKER'S OR
WOOD-WORKER'S BENCH, HOLDING MOUNTED BLUE PRINT.
AT LAST.
Large Unmounted Blue Prints Taken Care of
in the Shop.
For small prints,
rods unneces-
sary; may be
removed
and kept in
ool-room.
EXTENSION RODS ATTACHED TO CENTRAL DEVICE HOLDING
LARGE UNMOUNTED BLUE PRINT WITH GRAVITY CLIPS
A, A. B IS AN END VIEW OF THE DEVICE,
C THE LIFT, AND D THE ROD.
METHOD' OF FASTENING BLUE-PRINT HOLDER AND TEXT-BOOK
HOLDER TO BED OF LATHE
or any machine, by a fixed arm bolted to bed by two
hexagonal-head cap screws, f " x 16 x i|".
flETHOD OF FASTENING BLUE-PRINT HOLDER AND TEXT-BOOK
HOLDER TO BED OF LATHE
or any machine, by swivel arm bolted to bed by two
hexagonal-head cap screws, f'x i6x i|".
METHOD OF FASTENING BLUE-PRINT HOLDER AND TEXT-BOOK
HOLDER TO THE TOP OF BENCH
by flange screwed to bench, with four J"xi2 flat-head
bright wood screws.
METHOD OF FASTENING BLUE-PRINT HOLDER AND TEXT-BOOK
HOLDER TO BACK OF BENCH
by flange with three J"xi2 flat-head bright wood screws.
flETHOD OF FASTENING TWO BLUE-PRINT HOLDERS AND TEXT-
BOOK HOLDERS TO TOP OF DOUBLE BENCH
by double flange screwed to top of bench with eight J"x 12
flat-head bright wood screws.
Smith's Text-books on Machine Work are Standard
FIRST BOOKS ON MODERN INDUSTRIAL EDUCATION
TEXT-BOOKS ON MACHINE WORK
By ROBERT H. SMITH
Massachusetts Institute of Technology^
For Apprentice, Student, Specialist, Machinist,
Shop, School, College
They Cover a Field Heretofore Unoccupied "
AN EXPERT flACHINIST
says: "It has taken me a lifetime
in the shop to learn what is in
these books."
A flANUFACTURER says:
" Every apprentice, young ma-
chinist and machine specialist
[Price $2.oo Price $3.oo
should have these books."
AN INSTRUCTOR OF flACHINE WORK says: "For con-
densed and classified information and fine illustrations,
they are the most perfect books ever written on machine
construction."
The Finest Illustrated Text-books.
10
Read What Educators and Manufacturers Say
About These Text-books:
EXTRACTS FROn LETTERS
DR. RICHARD C. MACLAURIN, President Massachusetts Institute
of Technology, Boston, Mass. :
"You are dealing with matters that lie at the very basis of a great deal of the work
for which the INSTITUTE stands. The labor involved in putting these books together
must have been enormous."
MILTON P. HIGGINS, President of Norton Company, Worcester,
Mass. :
"The need of such text-books has been felt by teachers of shop work in all grades
of schools and engineering colleges, and I believe that such text-books are equally
desirable in commercial shops. It seems to me you have succeeded admirably in
this task. ELEMENTS OF MACHINE WORK and PRINCIPLES OF MACHINE WORK
show very broad, practical knowledge and unlimited, most excellent, clear and accu-
rate work in drawings, diagrams and tables. I cannot commend the books too
highly."
PROFESSOR PETER SCHWAMB, Massachusetts Institute of Tech-
nology, Boston, Mass. :
"These are the first books that I have seen that embody the systematic teaching
of the educational principles which should underlie industrial education."
FROM BROWN & SHARPE MANUFACTURING COMPANY,
Providence, R. I. :
MR. VIALL: "The books are so practical and helpful that we shall urge upon our
apprentices the purchase of them as a standard work."
MR. BURLINGAME: "I felt as soon as I looked these books over that they covered
a field which up to the present time had been unoccupied."
MR. BEALE: "I have nothing but praise for the books. My son says, 'The man
that wrote these books on machine work knows what he is talking about.' "
PROFESSOR FRANK E. SANBORN, The Ohio State University,
Columbus, Ohio :
"The books have been used in our classes in filing and machine tool practice and
have been much liked. The many neat illustrations, well notated, the concise state-
ments and instructions, and the tabulated matter give clearly and quickly the desired
information. The arrangement of the books is logical and pleasing to me."
ii
STONE & WEBSTER, Boston, Mass. :
MR. HENRY G. BRADLEE: "These books cover a field on which it is at present
almost impossible to obtain any information in a written form. I believe they will
be very helpful, not only to the young men who are studying machine work at Tech-
nology but also to all manufacturing concerns doing this character of work. I do
not believe that a machine shop could do better for itself than to put copies of your
books in the hands of each of its machinists."
PROFESSOR ARTHUR M. GREENE, Jr., Rensselaer Polytechnic
Institute (Russell Sage Foundation), Troy, N. Y.:
"I believe the books are going to be very extensively used as I do not know of any
books that quite cover the ground so well as these."
MR. LESTER G. FRENCH, Editor Journal American Society of
Mechanical Engineers, New York, N. Y. :
"One not familiar with publication work can scarcely imagine how much labor
is involved in the preparation of these volumes, but I know personally that the draw-
ings alone represent literally years of work and a large expenditure of money from
having kept in touch with your work."
PROFESSOR ARTHUR C. JEWETT, University of Maine :
"We have adopted your books as a required text for our classes in machine tool
practice."
UNITED SHOE MACHINERY COMPANY, Beverly, Mass.:
MR. VOSE: "They will be of great service to us in our INDUSTRIAL SCHOOL.
PROFESSOR CHARLES H. CHASE, Tufts College, Medford, Mass.:
"The large number of concisely numbered paragraphs, the tabulated arrangement
of the order of the work and the clear illustrations make the books unusually well
fitted as text-books."
MR. F. J. SCHULTE, Managing Editor Shop Notes Quarterly,
Chicago, U. S. A. :
"I wish to compliment you on the evident thoroughness with which these books
have been prepared and to congratulate you especially on the excellence of the illus-
trations, which are the clearest and most helpful I have ever seen in books of this
kind."
MR. JOHN C. BRODHEAD, Assistant Director of Drawing and Man-
ual Training, Boston, Mass. :
"I am delighted with the multitude of pertinent illustrations, with the tables and
with the simply worded text. I shall have the books put on the BOSTON AUTHOR-
IZED LIST."
12
MR. HAROLD F.^ RICHMOND, President American Emery Wheel
Works, Providence, R. I. :
"We have placed these books in the hands of the younger machinists in our factory,
We notice an immediate improvement in the efficiency of the men who use them.
Every apprentice should have copies of these books, and there are but few machin-
ists of any age who would not profit greatly by their use."
PROFESSOR HERBERT S. PHILBRICK, University of Missouri,
Columbia, Mo. :
"They are just what I have been looking for and they will save the instructor and
his assistants much trouble in giving notes to the students."
MR. WILLIAM H. DOOLEY, Lawrence Industrial School, Lawrence,
Mass.:
"Your books are the first books that I have seen that embody the educational
principles that must govern vocational education."
PROFESSOR FRANK M. LEAVITT, The University of Chicago
(Founded by John D. Rockefeller) :
"I have examined ELEMENTS OF MACHINE WORK AND PRINCIPLES OF MACHINE
WORK with much interest and I am astonished at the thoroughness and amount of
material which they contain. I can appreciate the experience which they represent.
Our machine shop instructor says they are the best books he has seen."
MR. ALLAN K. SWEET, Mechanic Arts High School, Boston, Mass.:
"You have put into clear, concise and usable form a vast amount of information
indispensable to the student and apprentice which only one who knows at first hand
both the business of machine construction and the business of teaching could have
selected. The illustrations are particularly satisfactory in character and execution.
They tell many things far better than could be done by words."
MR. W. H. MURRAY, Director Industrial Training, Newton, Mass. :
"We are using the text- books on machine work in the Newton Independent In-
dustrial School and in the Newton Technical High School."
MR. S. S. JUDD, Director of Manual Training and Trade Schools,
Saginaw, Michigan:
"These books fill a long-felt want, Text-books for the machine shop. I will
most certainly have each of our shop boys provided with the two volumes."
MR. LEO AMMAN, Instructor Machine Shop Practice, Stout Insti-
tute, Menomonie, Wis. :
"We have decided to use these as text books in our classes and I have no doubt
that we shall find them more than satisfactory."
MR. F. S. HITCHCOCK, Manual Training and Industrial School, New
London, Conn. :
"For clearness, accuracy and scope, they are the most perfect books on machine
work ever published. We are using them in our classes in machine tool work."
13
MR. FRANK CUSHMAN, Jr., Kansas City Manual Training High
School :
"They are splendid. There ought to be a great demand for such books."
MR. AMOS B. NOYES, Machinist, Waltham Watch Company, Wal-
tham, Mass. : after examining PRINCIPLES OF MACHINE WORK for two hours,
remarked:
"It has taken me a lifetime to learn what is in that one book."
MR. ORIN A. RINGWALT, North High School, Minneapolis, Minn. :
"These are the best books I have ever seen along the line of making machine work
a teachable subject.
MR. J. H. BURLINGAME, Jr., Ames, Iowa:
" ELEMENTS OF MACHINE WORK and PRINCIPLES OF MACHINE WORK, received a
short time ago, are O.K."
Read What the Technical Press Says About
These Text-books:
EXTRACTS FROH REVIEWS
MACHINERY, NEW YORK, N. Y., MAY, 1911. -
"At the present time when many so-called 'practical' books are making their
appearance, it is seldom that one is published which is as thoroughly practical. A
thorough treatment of the elements and principles of machine work is presented in a
style adapted to the needs of students in technical, manual training and trade schools
and apprentices in the shop. These books represent a great deal of painstaking
work on the part of the author, and his endeavors should be crowned with success,
for they meet the requirements of the class noted thoroughly, being expressed in a
clear, intelligible manner."
AMERICAN MACHINIST, NEW YORK, N. Y., MAY, 1911.
"There are years of experience in teaching shop work behind these books besides
the time previously spent in manufacturing, and we believe that many will find them
a decided help either in learning or in teaching."
SHOP NOTES QUARTERLY, THIRD QUARTER, 1911, CHICAGO, U. S. A.
"Every technical student and apprentice should possess copies of these Looks
which are quite the best of their kind that has yet appeared. The illustrations are
a revelation, every one having been drawn especially for the volumes and so clearly
lettered and captioned that they are practically self-explanatory of the processes or
operations they represent. The very complete index is also a praiseworthy feature."
14
CYCLE AND AUTOMOBILE TRADE JOURNAL, PHILADELPHIA, PA.,
MAY 1911.
"These two books show an intimate acquaintance with all branches of machine
tool work, combined with the knowledge of the teacher, and are undoubtedly the
first books embodying the educational principles underlying machine work. The
information contained in them is greater than that usually acquired during the life
of even an expert machinist. The subject matter is arranged in such a logical order
and so profusely and clearly illustrated, that even such a complex subject as that
treated cannot help but be clear to any one who consistently follows the course of
study as outlined. The books have already been adopted as text-books by many
of the leading industrial schools and should be invaluable to ambitious young men
engaged in machine work."
THE SCIENTIFIC AMERICAN, NEW YORK, N. Y., AUG. 12, 1911.
"Not technical students alone, but every youth who runs a lathe or uses tools as a
hobby, may benefit by adding this text-book to his working library."
THE JOURNAL OF THE WORCESTER POLYTECHNIC INSTI-
TUTE, WORCESTER, MASS.:
"The books cannot fail to assist in any shop instruction, and they should prove
valuable as text-books in shop courses given in most of the schools and colleges of
this country. There are no old cuts, copied from catalogues or previously printed
shop books, used in either volume. All cuts are from original drawings, many of
which are very dramatic in their execution and are illustrations in the true sense of
the word."
THE IRON AGE, NEW YORK, N. Y., APRIL, 1911.
"These two books have been brought out in an effort to supply text-books covering
the field of machine work, and the aim has been to give the beginner in these subjects
the advantages of text-books similar to those used in studying the older subjects, so
that the fundamental as well as the advanced principles may be quickly acquired in
a logical, systematic and progressive manner. In both books the student is told
how to do things and the theory connects principles and practice. Machines, mech-
anisms and tools are graphically illustrated by original mechanical and perspective
drawings and condensed tables describe them briefly and systematically. Con-
densed schedules which name the materials, the operations, the machines, the jigs,
the fixtures and the tools give operations in machining and standard and typical
problems in machine construction."
TECHNOLOGY REVIEW, MASSACHUSETTS INSTITUTE OF
TECHNOLOGY, BOSTON, MASS., APRIL, 1911.
"These two eminently practical treatises upon the operation of hand and machine
tools, constitute a substantial advance in the literature of the machine shop. This
series of books, of which the third volume on ADVANCED MACHINE WORK is in prep-
aration, well illustrates the systematic teaching of the educational principle which
underlies industrial education. They are the outcome of many years of faithful
study and practice upon the part of the author. It is believed that they will be
found equally useful in the school and in the shop."
IS
RAILWAY AGE GAZETTE, NEW YORK, N. Y., APRIL, 1911.
"These volumes have been written in a series of three on machine work with the
desire of placing text-books at the service of the student taking up this subject, either
in the trade schools or colleges. It is, however, of value to both the student and
apprentice. The former will find it more of a necessity, as his study of the work is
usually limited to a comparatively short time." v
CANADIAN ENGINEER, TORONTO, CAN., APRIL, 1911.
"The aim of these books is to give the beginner in machine work a text-book, that
he may acquire the fundamental principles in a logical, systematic and progressive
manner. Machines, mechanisms and tools are illustrated graphically by means of
perspective and mechanical drawings, and are briefly and systematically described
by tables. Operations in machinery, standard and typical problems in machine con-
struction are given in condensed schedules, which name the material, operations,
machines, speeds, feeds, jigs, fixtures and tools. These books tell how to do things
with that theory which connects principles and practice, and no person can build
or superintend the construction of machinery without consciously or unconsciously
understanding these problems and applying these principles."
INDUSTRIAL EDUCATION BOOK CO.
BOSTON, U. S. A.
16
THIS BOOK IS DUE ON THE LAST DATE
STAMPED BELOW
AN INITIAL FINE OF 25 CENTS
WILL BE ASSESSED FOR FAILURE TO RETURN
THIS BOOK ON THE DATE DUE. THE PENALTY
WILL INCREASE TO SO CENTS ON THE FOURTH
DAY AND TO $1.OO ON THE SEVENTH DAY
OVERDUE.
.V
I 9
JAN g4 ,
JUN 1 1948
JUN 1 5 1348
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Engineering
Library
257736
