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EVERY BOY
HIS OWN MECHANIC

BERNARD E. JONES

»*

PRKSENTKI) liV

EVERY BOY HIS
OWN MECHANIC

USING THE HACK SAW

llVork is several inches too high for comprt and efficiency]

EVERY BOY HIS
OWN MECHANIC

BERNARD E. JONES

I I

Editor of "Work"
ASSISTED BY A

NUMBER OF EXPERTS

Illustrated by Sixteen Full-page Plates in Half-
tone and Four Hundred Diagrams in the Text

New York

Funk & Wagnalls Company

JUL i I92S

To My Own Boys,
Lewis and Anthony

PREFACE

In this book I have tried to tell boys how to do some
of the things I have found them always eager to attempt.
I have explained and illustrated for them the everyday
tools of the worker in wood and metals, and shown how
to use them. I have described a variety of handiwork
and useful jobs about the house, and have introduced
my readers to a number of mechanical hobbies, such as
model electric lighting, wood and metal turning, model
locomotive and railway work, fretwork, boat building,
toy making, telephone construction and erection, etc., etc.
I may say that in almost every chapter I have sought
not only to present some interesting work or hobby, but
to show my boy readers how to make themselves useful
in their homes.

Much of the information in this book is " technical,"
but at the same time it is simple. In other words, I
have sought to explain in straightforward sentences
the " why and wherefore " of the methods and processes
described, believing that the need of the future is for
boys and men who understand what they are doing, and
why they do it. I have done my best to make every
statement easy of comprehension, and to use simple
language devoid of unexplained scientific or technical
terms.

vii

Preface

It is a pleasure to make a few acknowledgments of
help freely rendered me by personal friends. Mr. Henry
Greenly, the well-known model engineer, has contributed
two chapters on his own subject. Mr. A. Mill ward, a
highly skilled amateur mechanic, has explained how to
do simple turning in wood and metal. Mr. B. Clements-
Henry, electrician, craftsman, author (and ever so many
other things besides), has been good enough to go to the
trouble of designing an especially simple form of house
telephone, and of describing it in the very closest detail.
Then there are Mr. R. S, Bowers, who has drawn a number
of the best illustrations in the book, and Mr. J. G. Ross
— a technical chemist — who has kindly revised the chapter
on silvering glass. And I certainly must not forget to
thank my boy friend Ronald Gaze, and my son, Lewis
R. Jones, both of whom took pains in posing for a number
of the photographic plates. Still further acknowledg-
ments are made in certain of the chapters.

May my young readers find delight in putting into
practice the information which I give them in the pages
of this book.

B. E. J.

CONTENTS

How TO Use Woodworking Tools

Making and Using Various Cements

Erecting Electric Lamps and Bells

The Hektograph Copier : How To Make and Use It

Inserting a Window Pane

Various Workshop Metals : How to Identify and
Work Them .....

Making Picture Frames ....

How to Use Metalworking Tools

Glue : How to Prepare and Use It

Electric Batteries and How to Make Them

«
Soldering .....

Making Simple Wooden Toys .

Painting, Enamelling, and Staining

Fretwork in Wood .

Cleaning and Adjusting a Bicycle

Gilding with Gold Leaf and Gold Paint

Making Mortise-and-Tenon Joints

Building a Cardboard Model L. &
Locomotive

Turning Wood in the Lathe
How TO Mount Pictures .
Some Easy Things to Make in Wood

S.W.R. Express

1
35
41

65
70

74
82
94
105
111
125
138
153
161
172
190
194

204
219
231
237

Contents

Etching a Name on Metal
Varnishing and Polishing
Making Hutches ....
Waterproofing Tents, Ground Sheets and
Making Dovetail Joints in Wood
Turning Metal in the Lathe .
Fretwork in Metal and Ivory
Building a Dog Kennel
Laying the Rails for a Model Railway
Building a 10-ft. Flat-bottomed Rowing
A Model Aeroplane that Flies
Nails and Screws ....
Some Useful Jobs about the House
A Word on Wood ....
A Practical Home-made Telephone .
Index

PAGE

. 245

. 250

. 255

Garments 268

. 270

. 281

. 285

. 289

. 298

Boat . 307

. 319

. 328

. 330

. 340

. 343

. 367

LIST OF PLATES

Using the Hack Saw

rCHES

Rip-sawing

Tool Sharpening

Planing ....

Using Screwdrivers .

Wiring Electric Lamps and S\v:

Picture Framing

Filing at the Vice

Soldering ....

Easy Toy Making

Bicycle Cleaning and Adjusting

Model Locomotive, Station and Signals

Some Easy Things to Make in Wood

Dovetailing .....

Model Railways ....

Building Model Aeroplanes

Frontispiece^

FACING PAGE

8^*

16*^

80^
104«^
128*^
144»^

208^^
240^
272^
304''
320 -'

EVERY BOY HIS OWN
MECHANIC

HOW TO USE WOODWORKING TOOLS

The Bench. — The average boy mechanic is in my
mind as I write. He will be interested in a variety of
mechanical work, of which wood-working will be just
one branch, and possibly he may have no convenience for
a bench of his own, in which case perhaps he can use
another's or can
adapt a strong
table to his pur-
pose. Table
benches are use-
ful for light work,
particularly so
if there are side
and cross rails
near the floor, as

Fig.

1. — Kitchen Table fitted up as Wood-
working Bench

these add tremendously to the rigidity of the construction.
The average kitchen table is not rigid enough to withstand
the stresses set up by planing, but if it is used in the
corner of a room or against a wall, and the planing is
always done towards the wall, the table may be made
to serve very well.

B I

Every Boy His Own Mechanic

41HSiaB]

Fig. 2.— Iron Bench
Screw

Its chief lack will very quickly be discovered. There
is no vice in which to hold pieces of wood for chiselling,
tenon-sawing, etc., and the worker will not long be satisfied

without one. Fortunately, a vice
can be added to a kitchen table
at small expense {see Fig. 1).
Nearly every tool catalogue shows
both wood and iron bench screws,
both of them fairly cheap, and the iron ones {see Fig. 2)
can be rapidly converted into efficient vices. Should the
table-top overlap the side rail, as it almost certainly will,
first screw on a piece of wood as wide as the table rail, of
any suitable length, say from 6 in. to 12 in., and of such
a thickness that its outer face comes flush with the edge
of the table-top. If one piece of wood is not thick enough,
use two or three, and screw all together. For the cheek
of the vice you will need a piece of good hard stuff of
any convenient width, say, 6 in. wide and roughly 18 in.
long. The iron screw will vary in diameter, about eight
sizes between ye ^^•
and If in. inclusive
being obtainable.
You will need a
centrebit that will
cut a hole through
which the screw
will easily pass.
With this bit cut a ^^^- ^--^^"'^^ ""''' "'^ ^^^^^'° "^'"^
hole in the vice cheek, and right through the thickened
rail of the table. On the screw is a nut which must be
removed and screwed on the back of the rail in such a

How to Use Woodworking Tools

position that the bench screw engages with it freely.
There is also a collar which in the simplest form of con-
struction is split {see Fig. 2). In attaching the screw to
the vice cheek, it is pushed in as far as it will go, the split
collar placed in position so as to engage in a recess cut
in the screw, and the collar attached to the cheek with
half a dozen small screws. On turning the screw by
means of the lever handle, the vice cheek is moved to
and fro, but owing to its length it will not move per-
fectly parallel with the table unless a "runner" is fitted
to it. Now, B in Fig. 1 shows such a runner, and a is
the vice cheek, and Fig. 3 is
another view of it. The runner
may be of 1 in. stuff by 1| in.
deep, or any size similar, and
1 foot or more in length, tenoned
into the end of the vice cheek,
as shown in Fig. 4, it being Fig. 4.-Run^cnoned into
made a tight fit, and screwed ^**'® Check

from the front as indicated in the other views. A
long, narrow box in which the runner slides easily is
next made, but it is not fitted into position until
careful testing has shown what its exact position
should be. The presence of the runner, which should
fit its box well, but not tightly, will ensure that the vice
cheek is kept parallel with the side of the table when the
screw handle is worked. Full details of the arrangement,
which you can easily follow, are given in Fig. 5.

Two details of the illustrations need a word of comment.
In Fig. 3 is shown a planing board which protects the
surface of the table, and in which two little mortises have

Every Boy His Own Mechanic

been cut. Two pieces of wood (shown suspended over
the holes) fit the holes tightly and can be slightly raised
when required to form stops against which the work will
be held for planing. The other detail is the little L-iron
pieces screwed to the feet of the table legs in Fig. 1, and

PACT Of TA^LL-TOP ■ ^ INNER VICt-CHLDC •• fA.CE.

OWUlDs

BiaiiOtPACKiyiG-PllCL
TOEHABLLBCDCTOttFDOD

X MUn BL FLUSH V/HH EtXiL

/ OF X\6lL-TOP[AUT-a ^.-^

- FU/JH WITH FACl a TABLL-UG J

^^^^Vj^^^^^^^^K

RAILS OF ^,J\Z^'-^^'^^>^^Z^

6C?XHaD]MGA5a)«NEjL
HOfnOOE-TIHOllEDIJiTO

[A^AT4

jlf

TOP EDGE MUST EL ^
fLUfHWnHTi9P0fTABLL

UG a TAfcEL

Fig. 5.— Constructional Details of Kitchen -Table Bench

also to the floor to render the table immovable when
doing heavy work such as planing.

Of course, if you can afford to buy just the bench you
want, there are many excellent designs available. Those
with drawers or cupboards {see Fig. 6) are first-rate, and
full details of construction are shown on the opposite page.
The great advantage of a strongly-built "portable" bench
is that the whole construction is held rigidly by means of

4'6"-

1'6'.

A:^

3>i

L^ 2isq

Top of Leg

Dovetailed

to Rail

Front and End Elevations of Bench

Sketch of Complete Bench as in use

BENCH TOP
SCREW

Section showing how Vice
is fitted

Arrangement of Drawer
Runners, etc.

Fig. 6. — Sketch and Working Drawings of Bench with Shelf
and Tool Drawers

Every Boy His Own Mechanic

wedges which can be easily knocked out when it is re-
quired to take the bench to pieces for removal. The pin-
board on the front of some benches is for the purpose
of supporting long boards, one end of which will be held
in the vice and the other supported on a wooden peg
pushed into one of the holes at a suitable height.

Tools. — Sawing, planing and chiselling make up the
bulk of woodworking, and I advise you to buy just the
few tools that are essential and not to bother your head
or empty your pocket by obtaining a fitted tool chest.
Most of the tool boxes I have seen contain a number of
tools that are seldom required, and only the best of these
fitted boxes contain tools of really high quality. You can
do a lot of things with just a few simple tools of average
size and of good quality, kept in thorough order, and used
with as much care and skill as you can muster. I am not
going to bother you with a long list of the tools required
(I show two groups of them in Figs. 7 and 7a), except
to say that you will need a saw, a plane, two or three
chisels, and the everyday tools that most households
possess, such as a hammer, bradawl, gimlet, screwdriver,
2-ft. rule, etc. One or two other tools that would be
extremely useful will be referred to as the occasion for
their employment arises. The number of tools required
depends so much upon what you want to make and upon
the size and condition of the wood which you can get for
the purpose. For example, if you can obtain at a local
sawmill or carpenter's shop wood of any convenient
length, width, and thickness accurately cut and properly
planed, there is no need to buy a hand saw or a jack
plane, extremely useful though those tools are, and you

Haad Saw

Tenon Saw

Wooden Spokeshave

Brace

Fig. 7. — A group of fourteen of the Woodworker's chief Tools
and Appliances

Every Boy His Own Mechanic

can keep the money by you until you take in hand an
ambitious job where the tools mentioned cannot easily
be dispensed with. Under such conditions as I have
named a good tenon saw would answer most purposes,
but don't get a cheap one, and don't buy one at a
*' clearance sale " unless you get with it a guarantee
that it is by a good maker.

The hand saw is used for severing a board, and may
be used either with or across the grain, for which reason
it consists of a single piece of fine steel slightly tapered
in thickness towards the back so that it works sweetly
in the cut or kerf. The tenon saw is used chiefly in shaping
work in the making of joints and for other accurate
cutting of a finer and slighter nature than that which is
generally accomplished with the hand saw. It has a
thinner blade than the last mentioned, and very much
finer teeth, and to prevent its twisting or buckling when
in use it is strengthened with a back of brass or iron, as
shown in Fig. 7. Some tenon saws have a hinged back,
which can be pushed out of the way to allow of the saw
being used as a hand saw, but I have not yet seen a tool
of fine quality made in this way. A small brass-backed
dovetail saw will be found useful. Saws for cutting small
curves are the turn saw, compass saw, and keyhole saw.

How to Use a Saw. — Let our first attempt at wood-
working be the sawing of a piece of board accurately to
a line. The saw is to be started and maintained at work
so as to make a neat cut at right angles to the face of the
timber. Plenty of boys wonder why they cannot saw off
a piece of wood with a perfectly straight and square edge.
They get an edge which alters in its angle at every half

How to Use Woodworking Tools

inch, and in trying to correct it they produce another
edge just as bad and run the risk of making the work too
short for the purpose intended. The reason is that they

c:3i

Marking Awl and Knife

Twist Bit

Centrebit

Sliding Bevel

Twist Gimlet

Fig. 7A. — Another group of fourteen of the Woodworker's chief
Tools and Appliances

do not adopt the proper position. One of the photo-
graphic plates in this book shows the position for ensuring
that the saw is cutting square to the face of the work.

Every Boy His Own Mechanic

Look at it closely, and you will discover the secret of
accurate cutting. You will note that the saw, the fore-
arm, and the right eye are in one vertical plane, and if
you accustom yourself to working in this position you
will soon get into the habit of square cutting. Every
now and then you can test the accuracy by means of a

try-square (Fig. 8).

The saw must be
held as illustrated in
the photograph from
the very first cut to the
last. At starting it is
guided to the spot re-
quired by the thumb-
nail of the left hand
(Fig. 9), and the first
stroke is a short up-
stroke which just
abrades the edge of
the work and makes
an easy path for the
down stroke, which is
the real cutting stroke.
On the return upstroke
take all pressure off the saw, as the teeth are so
shaped that each one removes a little scraping when
the saw is thrust forward, but has only a slight
bruising action when drawn backwards in the cut.
The carpenter who presses the saw into the work on
the back stroke soon dulls his tool. Even on the down-
stroke do not press too heavily, and do not grip the

Fig. 8.

-Testing Accuracy of Sawing by
means of Try-square

How to Use Woodworking Tools

handle too tightly or the vibration will soon cramp
the fingers and tire the muscles of the arm.

To keep the saw to the line, the handle is very slightly
lowered occasionally, the eye observing that it is following
the path intended. But in taking pains to keep to the
line do not " lay " the saw too much, as you will then be
in effect increasing the thickness of the stuff and making
the job a harder one. But,
as I have said, unless you
lay the saw to some ex-
tent, you cannot be sure
of following the line.

In rip-sawing — cutting
with the grain — you will
need to support the work
at both ends, whilst for
cutting across the grain,
it is usual for part of the
plank to overhang the
box or sawing stool. In
both kinds of sawing the
parts requiring the most
care are at the begin-
ning and the end of the

cut, the first because accuracy and neatness depend
upon it, and the second because without careful work it
is easy to break off the partly-severed piece and leave
an ugly splinter. Thus you need to go slowly and
gently when approaching the end of the cut, and you
or a helper must support the work until the saw has com-
pleted the cut. The method of starting the cut is the same

Fig. 9.— Starting a Saw Cut

Every Boy His Own Mechanic

for both rip-sawing and cross-cutting. In your early
experiments, and especially if the saw is not in good
condition, the tool may become nipped when well into
the wood. This is because you have run the saw slightly
out of the straight, with a consequent tendency to bend
it in its width. You can overcome the trouble, as a rule,
by wedging open the cut with a chisel, or by starting the
cut at the other end of the board.

Fig. 11.— Bench Hook

Fig. 10. — Cross Halving

Using a Tenon Saw. — Tenon - sawing needs to be
much more accurately done than hand-sawing. You use
the tenon saw in preparing the ends of two pieces of wood
to be joined together, and any inaccuracy will probably
betray itself in the finished job. But with a little care
and using a good sharp saw you will rapidly overcome
any initial difficulty, and will soon learn to make a
straight square cut. It is held and started in the same
way, but otherwise is used differently, as it is frequently
necessary to cut a kerf the whole width of the board, and
the " laying " of the saw condemned in the case of the
hand saw is now unavoidable. In tenon-sawing it is

How to Use Woodworking Tools

often necessary to grip the work in the bench screw, and
alter its position from time to time so that all saw cuts
can be made in the vertical plane.

When making a halved joint {see Fig. 10) the tenon
saw is the chief tool used, and the work is generally held,
not in the vice, but in a simple device called a bench
hook (Fig. 11), which is used as illustrated in Fig. 12.
This bench
hook is a piece
of wood of any
suitable dimen-
sions with nar-
rower pieces
screwed across
its ends, one
on one face and
one on the
other. The left
hand holds it
and the work
which it sup-
ports firmly on
the bench, the

Fig. 12. — Sawing Halved Joint in Bench Hook

underneath strip which abuts against the edge of the
bench top preventing it from slipping.

However well a joint may be set out on the work, it is
quite easy to spoil it in cutting by inattention to one im-
portant point. It must always be remembered that a
saw wastes an amount of wood of a width equivalent to
the thickness of the saw measured across the face of the
teeth {see end view, Fig. 13). To give the saw clearance,

Every Boy His Own Mechanic

alternate teeth are bent or hammered sideways, the re-
mainder being bent in the opposite direction. The result
of this " set " is that a saw cut or kerf is of appreciable
width, quite enough in itself to make all the difference
between a good-fitting and a bad-fitting joint.

For example, two pieces of wood sawn off a length of
stuff measuring 3 in. by 1 in. are to be halved together to
make a cross. It is quite obvious that in each piece
must be cut a recess measuring exactly 3 in. wide and | in.
deep. Two lines are scratched or pencilled on
by the aid of the try square at right angles to
the edges of each piece, and exactly 3 in. apart.
These lines are continued across the edges of the
stuff, also by means of the try square, and a
line midway between the two faces is drawn
Fig. 13. upon the edges by means of a marking gauge
v"ew°of i^^S- '^^)' To avoid mistakes in cutting, pencil a
Saw heavy cross on the face and edges of the part

Teeth,

showing that IS to bc rcmovcd, and next make the
cuts with the tenon saw. If both cuts are
made exactly on the lines, half of each cut will be in the
body of the work and half in the waste that is to be re-
moved, and when the recess is finished, you will find that
you will have a loose fit, the recess being too wide by the
width of the saw across the teeth. If the cuts are made
outside the lines, the greater will be the discrepancy.
You will take care, then, to make the cuts inside of and
touching the lines. That is, in joint making saw-cuts
must always be made in the waste, whilst in cutting off
a piece that is required to be of precise length the cut
must also come inside the line, so that the piece is not

How to Use Woodworking Tools

robbed of an amount equal to the thickness of the saw
teeth.

Planes. — Everybody recognises a plane when he sees
it. The body is of wood or metal, and in it is held a cutter
or chisel at such an angle that it takes a shaving off the
wood when the plane is pushed forward. Long planes
are used for making the work flat and true, short ones for
bringing the work to a smooth surface. Trying or
trueing planes are
among the longest
in general employ-
ment ; next comes
the jack plane, the
most popular of all;
and the small plane
is the smoothing
plane.

In wooden planes
the cutter is held by a
wedge. Modern planes
are often of iron or
steel, and the cutter
is held in position and
is adjusted by means
of a simple screw. It is of not much use telling you
how to use a plane unless first of all you know how
to take it apart, sharpen the cutter, replace the iron
wedge, and adjust it to get a good result.

If you have an up-to-date metal plane, the method
of removing the cutter will be too obvious to require
description here. In the case of a wooden plane, either

Fig. 14.

-Striking Plane on Bench to
loosen the Wedge

Every Boy His Own Mechanic

jack or smoothing, the cutter can only be removed by
first loosening the wooden wedge. Take a jack plane in
your hands as in Fig. 14^ which shows the tool upside
down. The wooden part is held by the left hand, while
the right holds the wedge and cutter. Bring the plane
down smartly on the top of the bench, and this will have
the effect of releasing the wedge, and allowing the iron
to be withdrawn ; or, if you prefer^ hold the plane as in

Fig. 16. — Hammer-
stop or Striking-
button in Plane

Fig. 15. — Striking Plane with Hammer to
loosen the Wedge

Fig. 15, the right side up, the fingers of the left hand
reaching to its face, and the thumb being inserted in the
opening (which is known as the throat )j and press on the
face of the iron. Take the hammer in the right hand and
give two or three smart knocks on the top of the plane in
front of the left hand. This is a more gradual method
of loosening the wedge, but the hammer is liable to mark
the plane unless the latter has what is known as a
"hammer stop" let into it. Fig. 16 shows such a stop
in section. It is simply a plug of hard wood with a

How to Use Woodworking Tools

rounded top glued into a hole that has been bored in
the plane stock for its reception. This plug takes the
hammer blows and prevents disfigurement.

The plane is now in three parts — the stock, the wedge,

and the cutting
iron (Fig. 17).
Now, the last-
mentioned is
itself in two parts
{see Fig. 18) ; one
of these is simply
a wide chisel with
its corners very

Fig. 17.— Stock and Wedge of Jack Plane

Fig. 18. — Plane Cutter and Cap- or Break-Iron

slightly rounded off so as to prevent the cutter dig-
ging into the wood and leaving ridges. Screwed to
the cutter is the cap-iron, or break-iron, which does
not reach quite to the cutting edge, and which must
be removed before the cutter can be sharpened. If
c 17

Every Boy His Own Mechanic

you look at Fig. 19 you will see how a plane does its
work. The cutter is projecting slightly from the face
or sole, and pares a shaving from the wood over which
the plane is pushed. This shaving enters the plane
through a narrow mouth where it meets with the rounded
end or face of the cap-iron, which breaks its stiffness and
gives it a curved shape, so that as the plane continues to
work the shaving easily passes out through the wide
throat. In an old plane reduced by much wear the

mouth has be-
come wider than
it was originally,
and the shaving
tends to split
away from the
work because
there is not
enough wood im-
mediately in front
of the cutter to hold the grain down. Very often an
old tool is made serviceable again by gluing in a
block across its face so as to reduce the width of the
mouth.

To remove the cap-iron from the cutter is simply a
matter of undoing a screw. Now we have the cutter to
sharpen and set, and the work will afford us an example
of how all woodworking chisels are prepared for their
work. The hand chisel, for example, is sharpened and
set in almost exactly the same way as a plane iron, and
the one explanation will do for both of the tools. There
is just one difference. The edge of a chisel is straight,

Fig. 19. — " Cut-away " view of Jack Plane,
showing the working principle

How to Use Woodworking Tools

whilst that of a plane cutter is very slightly curved for a
reason already explained.

Sharpening Plane Irons and Chisels. — When you
receive a new plane, you may find that the edge of the
cutter has been ground but has not been sharpened.
Such a cutter may be sharpened many times for every
once that it will require to be ground. The grinding
angle is about 20°, and the sharpening angle about 30°,

Fig. 20.— End of

Chisel, showing

Grinding Angle (A)

and Sharpening or

Setting Angle (B)

Fig. 20a.— Showing

how Edge of Chisel is

spoilt by Bad Setting ;

note the Rounded

Angle

Fig. 21. — Cross -sec-
tion through Oilstone

and its Case ;

the Rubber Plugs hold

Case to the Bench

as indicated in Fig. 20. You can go on resharpening the
cutter from time to time until much of the grinding angle
has been worn away. Then the cutter must be taken
to somebody who has a grindstone and a new bevel of
20° ground on it. I won't trouble you with the grind-
ing, as not many boys have a grindstone of their own,
but the sharpening for which an oilstone is necessary is
an operation which you must master. The professional
woodworker gets easier and better results with edge tools
very largely because he thoroughly understands how to

Every Boy His Own Mechanic

keep them in order, whereas a great many amateurs fail
in this respect.

First you will need a good oilstone, and preferably it
should have a case (Fig. 21). If you have one already in
the house make that do. If you propose to buy a new one,
ask for a Washita, or an Arkansas, both of them natural
stones, or for a medium grade India stone, which is an

Fig. 22. — Sharpening or Setting a Chisel ; the Handle
is here shown a trifle too high

artificial product of a reliable quality. Have some sweet
oil in a can handy on the bench and grip the cutter or
chisel with the right hand, as shown in Fig. 22. Place
the fingers of the left hand lower down the tool so as to
provide pressure, whilst the right hand will see that the
proper angle (about 30°) is kept. This is where
difficulty will come in at first. The right hand will not
move to and fro quite parallel with the face of the stone,

How to Use Woodworking Tools

and the sharpened face of the cutter will have a rounded
instead of a perfectly straight surface {see Fig. 20a), but
that is a matter which care and practice will put right.

Anoint the stone with oil and start the rubbing. I
expect it will take you at least ten minutes at first to get
anything like a good edge on a blunt-ground chisel. Your
arms will ache and your hands be cramped, and you will
be tempted to leave off before you ought to and make do

—

. . : ;-p«i

Fig. 23. — Diagram indicating Side

Movement in Sharpening a

Plane Gutter

Fig. 24.— Rounded Edge of
Smoothing Plane Cutter (A)
and Jack Plane Cutter (B)

with an inferior edge. If you fall to the temptation you
will work far harder at a later stage than ought to
be necessary. You will waste time, and will fail to pro-
duce that proper, cleanly-cut surface which should be the
pride of every craftsman. Keep a chisel moving to and
fro in the same path, but a plane cutter should be moved
slightly from side to side {see Fig. 23) to produce the slight
roundness of edge of which I have already spoken, a
(Fig. 24) shows the edge of a smoothing plane cutter, and
B that of a jack plane cutter.

In the course of a few minutes you will see that the

Every Boy His Own Mechanic

rubbing is beginning to tell, but do not try the edge with
your finger, for obvious reasons ; the eye alone will tell
you when the bluntness has been rubbed off. Wipe the
tool when it has reached this stage on a piece of rag, and
notice that on the opposite face of the chisel a wire edge
has been turned up. This is removed by placing the
tool perfectly flat on the oilstone — avoid the least sus-
picion of an angle — and giving one or two gentle rubs.
The cutter should now be in good condition, but can be
made even keener by stropping it on a piece of leather

into which has been rubbed a
mixture of tallow and crocus
powder.

Sharpening Gouges. — Let
me drop a note in here on the
method of sharpening a gouge,
which, after all, is only a chisel
of curved section. There are two
Fig. 25.— Sharpening Gouge on sorts of gougcs as there are two
^*°°* sorts of chisels, the firmer and

the paring gouge, the firmer having the bevel ground on
the outside, and the paring gouge having an inside bevel.
The firmer gouge is sharpened in the same way as an
ordinary chisel except that the tool must be kept turning
to and fro as the curve demands (Fig, 25). A wire edge
will be turned up as before, and this must be removed on
an oilstone slip of curved section on which the gouge
will lie in intimate contact while being gently rubbed.

The paring gouge must be sharpened from the inside
on an oilstone slip, it being customary to hold the tool
still and move the slip to and fro, taking great care that

How to Use Woodworking Tools

the correct angle is maintained. To remove the wire
edge in this case, place the gouge flat on an oilstone and
give a gentle rub or two whilst slightly revolving the
tool, in this case, also, taking the very greatest care
not to produce an opposing bevel. Gouges should be
well stropped.

Re - assemblin£f the
Plane. — Now we can get
back to the plane. The
cutter has been sharpened
and stropped to a wonder-
ful keenness, and we wish
to get it back into the stock
and see what it can do.
Holding the cutter in one
hand and the cap-iron in
the other, slide them to-
gether until the cutting
edge projects by, say, two
or three thirty-seconds of
an inch. Then tighten up
the screw, and place the
double iron in the throat of
the plane. The thumb of
the left hand will hold the cutter in position until the
wedge can be pushed in firmly. Lean the back end of
the plane on the edge of the bench in such a position
{see Fig. 26) that you can sight down the sole or face and
observe the exact amount by which the cutter projects.
A very slight projection is all that is required. Give the
wedge a tap or two with the hammer, and the cutter will

Fig. 26.— Sighting along Sole of
Plane for Projection of Cutter

Every Boy His Own Mechanic

be fixed. Again sight down the face, and if the cutter
projects too far give the front of the plane a light blow
with the hammer and again give a tap on the wedge.
On the other hand, if there is not enough projection, give
the cutter a gentle tap from the back, all the while sighting

down the sole to see
you don't over-do it.
Using a Plane. —
You will be anxious
to try the plane. The
method of holding it
in the case of a jack
plane or other large
tool will be quite ob-
vious from Fig. 27.
The handle, called a
toat, is grasped by the
right hand, while the
left hand bridges the
front, the thumb being
on the near side and
the four fingers on the
other side, as illus-
trated.

Fig. 27. — How to hold the Jack Plane

A smoothing plane has no handle and needs to be
grasped firmly at the back by the right hand, as in Fig. 28,
whilst the left is passed right round the front end, the
thumb lying on top of the plane, and the fingers
extending to the far side.

The jack plane should be given a straightforward
thrust, each stroke being as long as the work demands or

PLANING

Holding a Jack Plane

Position when Planing

Testing Planed Wood Across
the Grain

Sighting a Piece of Planed Wood
for Straightness

How to Use Woodworking Tools

as the craftsman can make it. Just as the cut starts,
the left hand presses down the front of the plane, but
gradually this pressure is released as the stroke nears
its end. You will need to hold yourself correctly. Stand-
ing in front of the bench, the right foot will point towards
it whilst the left will be parallel to it, the direction of
planing being towards the left. If the tool fails to take
off a thin even
shaving and if you
are convinced that
it is in good order,
you had better
make quite sure
that you are not
working against
the grain, as this
has the effect of
splitting off the
shavings as they
are formed. Should
it happen, reverse
the work. Of
course, wood with

a very curly grain is not easily planed ; indeed, sometimes
planing has to be replaced by the use of a woodworker's
scraper, which is a piece of flat steel with a keen but
turned-over edge.

Much the same advice applies to the manipulation
of the smoothing plane. It must be lifted sharply on
reaching the end of the stroke so as not to leave a mark ;
and it is unwise to attempt at first to plane end grain

Fig. 28. — How to hold the Smoothing Plane

Every Boy His Own Mechanic

with it, although in cases where this must be done it is
usual to pare away the extreme end of the edge that is
to be planed ; another dodge is to clamp on a piece of
waste stuff so that if the grain of the wood is split by the
plane the damage will occur to the waste and not to the
work.

The Scraper. — Not many amateurs can use this
simple tool successfully. I mention it because it is an
alternative to the plane when working on curly-grain
woods, whilst on other woods it is used after the smoothing
plane. Fig. 29 shows the principle on which it cuts, and
Fig. 30 the tool itself. The cutting edges are a b and
c D, and the rounded corners should be noted. It is
used as in Fig. 31. the scraper being pushed away from
the worker, as from a to b, but occasionally it is manipu-
lated in the reverse direction. The scraper must have been
ground with square edges, and these should be brought
into perfect condition by rubbing on the oilstone in the
position shown by Fig. 32, afterwards placing it flat on
the stone (as in Fig. 33) and removing any burr. Then
rub with a polished gouge (as in Fig. 34) till the sides are
polished; again squaring the edge on the stone should
any burr be caused. The next proceeding is to turn up
a very fine burr (this is much exaggerated in the diagram,
Fig. 29), to do which the scraper is laid flat on the edge of
the bench, as in Fig. 35, and a polished gouge or any
similar smooth steel tool used in an upright position is
lightly pressed about twice along the edge at right angles
to the flat sides of the scraper. You will probably need
to make a good many attempts before you succeed (re-
setting the tool on the oilstone every time), but success

How to Use Woodworking Tools

is worth while, because the scraper is a wonderful tool-
a real cutting and not a scraping tool — and its " sweet
use gives a lot of pleasure.

Fig, 33

Fig. 29

Fig. 29. — Working Principle of Woodworker's Scraper

Figs. 30 and 31. — Scraper and how to hold it

Figs. 32 to 35. — Four Stages in sharpening the Scraper

Chisels. — The boy mechanic will show his excellence
as a carpenter by his skill in the use of a chisel. Every-
body knows the shape of the ordinary chisel, and I will
only say that the long thin chisel is used for paring, and
a shorter one, the firmer chisel, for making mortises, etc.,

Every Boy His Own Mechanic

for which purpose it is driven with a mallet. Carpenters
have a very thick chisel known as a mortise chisel with
which to lever chips out of slots. Ordinary chisels vary
in width from -^^ in. to 2 in., and they are sharpened
exactly as a plane iron {see p. 19), except that the edge
forms a straight line, whereas in a plane iron the corners

are rounded
off. On a grind-
stone a chisel
is ground to an
angle of 20° or
25° (the latter
for hard wood),
but this is not
the angle ad-
hered to when
the chisel is
placed on the
oilstone. Some-
thing a trifle
blunter is
aimed at, so as to give the edge greater strength ; thus the
set or sharpened edge forms an angle of about 30° to 35°.
Fig. 20, on page 19, shows the working end of a chisel,
and it will be seen from this that the tool can be
repeatedly rubbed up on an oilstone until most of the
ground bevel has been worn away. Then regrinding on
a grindstone becomes necessary.

I believe the great trouble in using chisels is the diffi-
culty of making and keeping them sharp. Beginners
don't seem to be able to get a straight bevel. They get,

Fig. 36. — Paring on the Slant

How to Use Woodworking Tools

instead of the flat facet, a rounded face surface with which
sweet cutting is impossible {seeFig. 20a). Practice sharp-
ening the tool until you can do it really well, and the actual
use of the chisel will then be a much simpler matter.

A chisel is used for two purposes — paring by hand and
chipping when driven by a mallet. By the way, don't
hit the handle of a chisel ^*-t-
with a hammer ; use a '

wooden mallet. Just be-
cause a chisel is sharp^,
and you like to swing
your mallet, do not be
tempted to take out deep
chips. It is so easy to
overstep the mark, and
also to splinter the work
on the side farthest from
you. The best practice
is to remove a chunk of
wood by means of reason-
ably thin parings, and Fig. 37.-Vertical Paring of Corner

paring may be done horizontally or vertically, which-
ever you find the more convenient.

Sometimes paring is done on the slant, but, of course,
do not try to pare against the grain, or you may split
the work. In other words, when paring off a corner
{see Fig. 36), start from the side, and cut slantwise across
the grain, the wood being held upright in the vice so that
the pared surface is approximately level. You can pare
off a corner by having the wood quite flat on a bench,
and here again you must start at the side of the wood

Every Boy His Own Mechanic

and work towards the end {see Fig. 37), as otherwise the
chisel may easily dig in and split the work down the grain
when the chisel nears the side. An experienced wood-
worker would use the chisel in a job of this sort with a
to-and-fro motion, so that the edge of the tool enters the
work much as would the blade of a knife. If you take
up a stout piece of wood, and try to remove a thick chip
from the end with a knife you will almost unconsciously
give the knife a slight movement lengthwise as well as

forwards so as to
facilitate the cut-
ting action. The
same principle
frequently applies
in using a chisel.
Try to sharpen a
thick pencil with
a chisel and you
will get the idea
at once.

Makingf a Halved Joint. — There is a common joint
which will afford us some practice in using a chisel. It is
the halved joint (Fig. 10, on page 12) to which I remember
my first introduction was in the making of a toy sword,
in which it is customary to sink the crosspiece flush
with the handle.

By means of a square two lines are set out on the face
of each piece, the distance between these lines being the
width of the stuff. On both sides of each piece the lines
already drawn should be squared over (Fig. 38), and at
half the thickness^ there is drawn a line with a gauge

Fig. 38. — Setting-out and Working Gross-
halved Joint

How to Use Woodworking Tools

parallel with the face of the work ; thus both pieces are
set out in exactly the same way. Mark with a cross any
pieces to be cut out. Next, with a fine saw held perfectly
upright, cut down on the lines until the half thickness is
reached, treating both pieces in the same way. On your
discretion in cutting these lines will depend whether the
joint is a good fit {see
page 14). If you were
now to take a chisel
and a mallet, place
the edge of the chisel
on the horizontal line
connecting the bot-
toms of the cuts, and
then give a good blow
with the mallet, prob-
ably two things would
happen. A notch with
an uneven slanting
bottom would be
formed, and the
farther side of the
work would be badly
splintered. So first study the grain, and if you can
see that such a course would be safe, you can take a
good thick chip to start with, and then, using the chisel
carefully — if the notch is a wide one adopt the sideways
movement of the chisel — pare down, as in Fig. 89, until
you have formed a flat surface flush with the line scribed
on the side. Treat both pieces in the same way, test
the bottom of the halvings for flatness and squareness,

Fig. 39. — Horizontal Paring in making
a Halved Joint

Every Boy His Own Mechanic

fit the joint together, and make any adjustment required.
In deepening the notch by a slight shave, if this should
be necessary, the chisel is afterwards used as a knife to
detach any parings that may still be held by their edges
{see Fig. 40) ; it is drawn along in the angle of the cut with
its front point raised, the flat of the chisel being in contact
with the wall of the notch.

Fig. 40. — Cleaning out the Halving with
Corner of Chisel

Fig. 41.— Starting
Chisel on the Slant
in Overhand Paring

Overhand Paring. — For paring a short length off the
end of a piece of work, start the chisel on the slant, as in
Fig. 41, and when you feel that it is making progress
bring it to the upright. Cut only a little at a time, and
the work will be easier and of cleaner finish ; this applies
to all chiselling. It will be obvious that in vertical paring,
known as overhand paring, a great deal more power can
be applied to the chisel. The work should be so held

USING SCREWDRIVERS

Ibk

^«l^

^5!"

- y

wm^

M|piM

Hi.9

■SS

j^%."jUilllff^

!•

]

Narrow Screwdriver Injures
the Screw-head

Slanting the Tool Injures Screw-
driver and Screw-head

Removing Damaged Screw
with Spanner

Using Screwdriver-bit
in Brace

How to Use Woodworking Tools

that the eye can look down the chisel and see that the
paring is quite vertical. The left hand will hold the tool
near the point and guide it to its work, while the right
will grasp the handle, the^thumb coming on top {see
Fig. 36).

In later chapters I will show you how to make a few
simple joints — the dovetail among them — and will illus-
trate and describe a few wooden constructions upon which,
if you can get the material, you may try your 'prentice
hand.

Screwdrivers. — The selection of a screwdriver is
more important than some boys think. One of the plates
in this book shows a narrow screwdriver used on a stout
screw, the effect being to spoil the edge of the screwdriver
and injure the head of the screw. To the right of this in
the plate is a screwdriver held at a slight angle, a common
ault with careless people. Here, again, the head is
easily damaged, and once broken it may be difficult to
get the screw out again. One method is to square the
head with the file and to withdraw it by means of a spanner,
this operation being shown in the plate. The screwdriver
point or end should be almost parallel in thickness, and a
fairly good fit in the nick of the screw. A powerful form
of screwdriver is a brace into which a screwdriver bit has
been inserted, such a combination being shown in use in
the plate already referred to. I often use this device for
driving long thick screws, but I find it has a big dis-
advantage ; it is difficult to maintain the pressure so as to
prevent the bit slipping from the head of the screw.
The arm or crank of the brace gives enormous power, so
much so indeed, that if the head of the screw is weak, or
D 33

Every Boy His Own Mechanic

the point of the screwdriver bit is inclined to be hard
and brittle, either or both may be broken.

The effect of using a screwdriver wider than the screw
is to mark the work should it be necessary to insert the
screw flush with the surface. The ordinary wood screw,
actually of steel but known as a wood screw to differentiate
it from screws for metalwork, has a countersunk head,
and in careful work it will be necessary to chamfer or
countersink the screw hole to accommodate it. The
countersinking can be done with gouge or chisel or by
means of a nose-bit or special countersinking bit used in a
brace.

To remove rusted-in screws, put the screwdriver in
place in the nick and give a smart knock with a hammer
to break the rust joint ; or try the effect of expanding
the screw by heating it with a red hot poker.

I give some information on the use of nails and screws
in a much later chapter.

MAKING AND USING VARIOUS CEMENTS

Cementing a Rim on a Biscuit Barrel. — These in-
structions will apply just as well to the fixing of a mount
or rim to the reservoir of a lamp, a glass pepper-pot, glass
inkstand, and many other things. First with a bradawl
scrape away the old cement from the glass or china article
and also from the mount or rim, but take care in the latter
case that you don't bend the metal and spoil the fit.
Put some boiling water in a cup and drop in some crystals
of alum, adding more and more until the water refuses
to dissolve any more of the substance. Such a solution
as this, as you have probably learnt in your chemistry
lessons, is known as " saturated." When it is fairly
cool, put a couple of spoonfuls of perfectly fresh plaster-
of-paris in a saucer, add some of the alum solution, and
mix up rapidly to a rather wet consistency. Then,
without waiting, put some of the cement on the vessel or
in the mount, and press the two parts into close contact,
taking the greatest care that the mount " sits '* square
and level. In half an hour's time any surplus plaster can
be scraped away, and the vessel can be used twenty-four
hours later.

Another way, equally good, is to use powdered alum
alone. First see that the articles are free from dirt and
grease. Powder the alum, place the rim upside down,

Every Boy His Own Mechanic

fill it with the powder, and put it on a metal plate over a
low gas flame or on the warm kitchen range, and you will
note that in the course of a few minutes the alum will
get pasty. When this occurs, press the glass or china
article firmly into the rim, quickly invert, see that the
rim is in its correct position, and put aside for half an
hour in a cool place, when the article will be ready for use.

Cementing Celluloid and Xylonite. — Boys and girls
use lots of things nowadays that are made of celluloid
(xylonite is only another name for it). Girls have combs
and hair ornaments and brush-backs and ping-pong balls
of this material, whilst boys have celluloid knife-handles,
celluloid accumulator cases and celluloid films for hand
cameras and cinematograph machines. By the way, I
once had some beautiful hair-brushes which I thought
had backs of fine ivory, but one day I touched them with
turpentine, and immediately I became aware of a faint
smell of camphor. They were celluloid I You will know
now how to test yours. It is just as well to find out
which articles are celluloid and which are not, because,
as you are probably aware, this substance ignites with
an almost explosive violence.

When celluloid gets broken, it may generally be easily
cemented. It dissolves very readily in a liquid known as
amyl acetate, which you will know by its strong smell of
those sweets sold under the name of " pear-drops." So
all you have to do when you want some celluloid cement
is to put a few scraps of a broken celluloid toy, etc., in
I oz. of the amyl acetate, and after the celluloid has dis-
solved apply the solution with a camel-hair brush, and
bring the two parts together. An excellent solvent for

Making and Using Various Cements

celluloid is a mixture of equal parts of acetone and the
amyl acetate. "Non-flam" film (made of a celluloid
substitute which does not readily ignite) will not dissolve
in either of the above, but will be found to do so readily
in chloroform, which when not in use must be kept in a
tightly stoppered bottle, a point which applies to all
c.eUuloid solvents and cements. But chloroform is danger-
ous stuff in the hands of inexperienced people.

Fig. 3. — Cinemato-
graph Film joined
together

Fig. 1. — Torn Cine-
matograph Film

Fig. 2. — Film with

Picture Space

cut out

Cinematograph films are made of celluloid, and if you
are called upon to repair them (they easily get torn when
in use. Fig. 1 showing an example at a and b) you will
need to cut out a picture, but this will make no appreciable
difference to the effect on the screen. Cut the film as in
Fig. 2, making one cut at the dividing line b, but leaving
a little strip a, below the dividing line cd. Place the
piece containing strip a on the table, and, first wetting
the strip with the tongue, carefully scrape away the photo-

Every Boy His Own Mechanic

graphic emulsion or gelatine below the line c d, using a
penknife. Then apply the cement already mentioned to
the back of b, and bring the two together, taking par-
ticular care that the joint is absolutely square and other-
wise correct {see Fig. 3). Keep under pressure till dry.

China and Glass Cements. — I suppose most of my
readers are called on some time or other to repair a broken
article of glass or china. There are scores of cements
that may be used for this purpose, apart from those that
can be bought ready made. Plaster-of-paris, mixed with
a solution of alum, as already explained, will mend china,
but not so strongly as to allow of the article being washed
with hot water or used as a hot-water container.

An excellent cement for either china or glass is sodium
silicate which possibly is employed in your household
under the name of " water-glass " for preserving eggs.
It should be used exactly as it comes from the lever-lid
tin in which it is bought, and should be applied thinly,
but it is desirable to warm the article, and the water-
glass is more easily applied if it is warmed too. The
article requires to be held together by tying tightly with
string or by some other means until the joint is hard.

A first-rate cement for china, glass and stone is a
mixture of water-glass, manganese, and zinc white all
ground up together ; and a putty that answers well for
glass can be made by mixing chalk with water-glass. It
is even better than the usual oilshop putty in one respect
— it only takes a few hours to dry.

A good many boys turn their hand to the making of
an aquarium, and the usual cement used for this purpose
is a mixture of various oxides of lead. One of the easiest

Making and Using Various Cements

to make consists of the best quality white-lead, bought
already ground up in oil, mixed with equal parts of dry
red-lead and dry litharge. But remember in using lead
cements that they are poisonous ; they should not, there-
fore, be worked up in or applied with the hands, and after
they have been given a week or two in which to dry and
harden, the aquarium should have many changes of water
before introducing either pond weeds or fish. Perhaps
the safest way is to give the cement a few days to dry,
and then apply three coats of good varnish, allowing at
least two days for each coat to dry before applying the
next. In any case, a few small minnows should be tried
in the water before introducing valuable fish.

Cementing Solid Tyres to Rims. — In the old days
before pneumatic tyres were known, the solid tyres
with which the " ordinary " bicycle was fitted had to be
cemented to the rim. Nowadays, it is only mailcart
and perambulator tyres — and those not of the best quality
— which are so fixed. Should a tyre of this kind — the
non-wired kind — become loose, you will find it a fairly
simple matter to re-cement it in place, but it is a job
requiring some amount of care. The cement used is a
mixture of gutta-percha and pitch, and can be bought at
any hardware stores. It may be used just as though it is
sealing-wax, and the empty rim smeared with it all round,
heating the cement in a candle flame or by means of a
red-hot poker. The cement having been applied, stretch
the tyre into place, and spin the wheel on its axle. Have
ready a spirit lamp, which, as you know, has a smokeless
flame, and as the wheel spins approach the flame to the
rim so as to melt the cement evenly all round. Keep the

Every Boy His Own Mechanic

wheel rotating, as otherwise there is risk of spoiling any
paint or enamel on the rim, which, in any case, will not
be improved in appearance. You can make a very cheap
but efficient spirit lamp from a ginger-beer bottle by
pouring into it some methylated spirit and then stuffing
in a wick made of loose cotton strands.

In the chapter on Cycle Adjustments and Tyre Repairs
I deal with the cementing of patches on pneumatic tyres.

Using Portland Cement. — If you have occasion
to use Portland cement, small quantities of which can
be bought at oilshops, of builders' merchants, etc., mix it
thoroughly with an equal measure of perfectly clean and
fine sharp sand, add a little water, and at once continue
the mixing until you see the mortar is of a nice even texture.
This will make a very strong cement and a more durable
one than if the sand were omitted. For cementing a
brick into place, or for any odd repair about the yard or
garden, you can mix two measures of sand with one of
cement. I put in a splendid floor to a summerhouse once
with a concrete made by mixing 1 part of cement with
4 or 5 parts of sandy gravel dug up from a pit made in
my garden. Such a floor will last scores of years, whereas
a wooden floor often decays in a few years' time.

ERECTING ELECTRIC LAMPS AND BELLS

Batteries. — What a great convenience it is to have
an electric light over your bed ! I shall show you in this
chapter how you can instal a tiny electric lamp more than
enough to see the time by ; you can make the battery,
erect the wiring, and connect up the lamp yourself, and
be independent of any main-supply system. I have said
you can " make " the battery ; so you can, but it is
generally cheaper to buy it already made. However, 1
expect you are one of those boys who glory in making
everything for themselves, and so in another chapter I
am giving you full instructions on how to make a battery
suitable for running a pea-lamp for a few moments at a
time, using it only occasionally over a period of several
months. This type of battery {see pages 112 to 115) is
known as a primary battery, and it produces an electric
current by the chemical action of the substances with
which it is charged.

There is a much more convenient type of battery,
known as a secondary or storage battery, otherwise an
accumulator. It contains lead plates immersed in dilute
sulphuric acid, and is charged with current from a dynamo,
from a primary battery, from another accumulator, from
the electric-light main, or from whatever source of electric
current happens to be convenient. The primary battery

Every Boy His Own Mechanic

once exhausted needs to be recharged with chemicals ;
the accumulator, when run down, simply requires a new
electric charge. The accumulator is more expensive
than the primary battery, but can receive and yield a
far greater amount of current, and is a more reliable
appliance.

Now for a bedroom or workshop light, one or other of
these devices is necessary unless, of course, you can afford
a little dynamo and to run it by means of an engine of
some kind ; but, generally speaking, the cost and the
attention needed by the engine make such an arrange-
ment rather out of the question, and most boys fall back
on the accumulator or the simple primary battery.

In another chapter, I explain how a Leclanche cell or
battery is made. A really big cell of this type, say one
that will hold about two quarts, will keep a metallic-
filament quarter-ampere lamp glowing brightly for several
minutes, after which it needs several days to build up its
reserve of strength once more. Very few primary cells
can ring a bell or light a lamp for long together. But this
same big cell might last a year without giving any trouble,
if it were just used now and then — a few seconds at a
time — for illuminating a watch-stand, the face of a clock
or the reception-room of your sister's doUs'-house.

Much better results can be had from an accumulator
of much smaller dimensions. A 4-volt accumulator of
what is known as 5-ampere hour capacity would light a
number of tiny lamps giving a total of 2 candle-power for
as long as ten hours, which means that, as in " miniature "
or " model " lighting, the lamps are seldom " on " for
more than very brief periods at a time, the accumulator

Erecting Electric Lamps and Bells

would last a long, long time on one charge, which charge,
by the way, would cost only a few pence.

Some Electrical Terms. — Amperes and candle-powers
are all very well as terms, but what do they mean ?
asks the reader who is new to this sort of thing. Well,
we speak of the volume of an electric current in " am-

Fig. 1. — Miniature Metallic-filament Electric Lamps

peres," just as we speak of so many " gallons " of water.
The force that drives a volume of current through any
substance is measured in " volts," and the resistance
which anything offers to the passage of the current is
measured in " ohms." You must always remember these
three terms — volts, amperes, and ohms. You must try
to imagine a piece of any substance striving to prevent by

Every Boy His Own Mechanic

means of ohms of resistance the passage through it of
amperes of current which are being pushed along by volts
of pressure or electromotive force. The pushing power
is often referred to as " E.M.F.," meaning electromotive
force, or as " difference of potential," or simply as " pres-
sure." Amperes multiplied by volts gives us another
term — watts. If I tell you that with small metal-filament
lamps you can get 1 candle-power of light from 1 watt of
current you will understand that a 1 -candle-power lamp
marked 0.25 ampere will require a pressure or voltage of
4, because a watt is simply the product of amperes and
volts multiplied together. Quarter-ampere multiplied by
4 volts equals 1 watt, and 1 watt in the type of lamp we
have in mind equals (about) 1 candle-power.

Systems of Connections. — Perhaps you know that
when glow lamps first became popular their filaments
(very fine wires) were of carbon, but nowadays lamp
filaments are made of one of the rare metals, chiefly
tungsten, and they give a better light than the carbon
lamps and use less current.

Why does the lamp glow? Simply because its fila-
ment offers such a high resistance to the passage of the
current that it become intensely hot, and, as everybody
knows, most substances when raised to very high tempera-
tures emit light. The filaments cannot burn because
the bulbs have been exhausted of air. If you obtain a
catalogue from a dealer in the smaller electrical supplies
you will find in it particulars of a great variety of miniature
lamps of different shapes and powers, and you will have
no difficulty in selecting them to suit the supply of current
you happen to have, but before you can tell exactly which

Erecting Electric Lamps and^Bells

lamps to order, you must know how you propose to
arrange them, and must understand the two or three
methods of connecting up both batteries and lamps.
There are two poles or terminals to both of these devices
{see Fig. 1a). A battery has a positive pole at which the
current is supposed to return. Inside the battery, current
is supposed to pass from the negative pole to the positive.
Thus the very first lesson to be learnt is that you must
provide a circular path for the passage of a current. Not

Neaafive
Pole

tkoafive Plate
or E lee trod A

flcldulated
Water

fhsitire Plate
•or Electrode

Fig. 1a. — Experimental form of Electric Cell or Battery

only must you take the current out, but you must bring
it back again. We will take a little cell and a two-yard
length of copper wire. We will attach one end of the wire
to one pole, and the remaining end to the other pole.
In this way we have provided the circular path (as in
Fig. 2), and current will instantly flow ; indeed, it will
flow so easily that the battery will rapidly run down.
The more resistance we offer to the passage of the current
the longer will the battery remain in condition.

Every Boy His Own Mechanic

We will cut the wire in the middle. There are now in
effect two wires, one from each pole, and no current can
flow. Taking a miniature lamp or even an electric bell,

Fig. 2. — Cell and Simplest Circuit

we connect the outer ends of the wires to the terminals
(Fig. 3). Once again the circular path is provided ; we have
" completed the circuit," and the current will at once
do its work by causing the lamp to glow or the bell to ring.

Fig. 3. — Cell, .Electric Bell, and Simplest Circuit

We have now an electric circuit of the simplest possible
kind. We can cut again where we like, and introduce a
simple switch or push, by means of which we can " make "

Fig. 4. — Cell, Bell and Push, and Simplest Circuit

or " break " the circuit and glow the lamp or ring the bell
whenever we like (see Fig. 4).

Lamps or batteries so arranged that the whole of

Erecting Electric Lamps and Bells

A A

Fig. 5

Figs. 5 and 6
— Examples
of Lamps and
Cells con-
nected in
Series (A, ac-
cumulator ; F,
fuse or safety
device; S,
switch)

HHH

Fi«. 6

the current passes through each and all of them are said to
be connected in " series " {see Figs. 5 and 6). Essentially
the entire circuit is one endless path with the bells or lamps
or batteries distributed to suit convenience.

In a battery of cells connected in series the total
voltage equals that^of all the individual cells added to-

Fig. 7

T T T T

Fig. 8

Fi^s. 7 and 8. — Examples of Lamps and CelU

connected in Parallel

Every Boy His Own Mechanic

gether, but the current in amperes is no greater than that
of one cell. For example, two 2-volt cells each giving
1 ampere of current give, when connected in series, a
current of 1 ampere at a pressure of 4 volts.

In what is known as the " parallel " system, the current
consists of the two main wires with the bells, batteries,
etc., disposed between them — bridge fashion — with one

Figs. 9 and 10. — Examples
of Lamps and Cells
connected in Series-
Parallel

- 1 1

li:)i'.

r i -r 1

Fig. 10

pole of each connected to one main and the remaining
pole to the other. Such a system is clearly shown in
Figs. 7 and 8. Cells connected in parallel to form a battery
have a total voltage equal to that of one cell only, but
the yield in amperes is multiplied by the number of cells.
Thus the two cells already mentioned would give in parallel
a current of 2 amperes at a pressure of 2 volts.

Often a circuit has batteries connected in series and
lamps or bells in parallel. This is known as series-parallel

WIRING ELECTRIC LAMPS AND SWITCHES

Tightening the Pinch
Screws

Gutting off Ends of Wire Strands
with Scissors

Fixing Cord Grip of Lamp Holder

Wiring-up a Wall Switch

Erecting Electric Lamps and Bells

(see Fig. 9). In Fig. lOj there are four cells disposed in
tAvo sets. The two cells in each set are in series with one
another, and the two batteries so formed are in parallel
with one another. If

each individual cell is
2-volt, 1-ampere, the
current yielded by the
whole battery will be
2 amperes at 4- volts
pressure.

Erecting Lamps
and Bells.— With this
theoretical information
we may pass on to the
practical work of in-
stalling one or more
lamps or bells.

You will have de-
cided on the type of
battery you are going
to use. Unless it is
an accumulator or a
home-made device, you
will probably prefer a
dry cell or cells, because
they are non-spillable.

Differ rermmal to be
■ connecred h push and-*',
rhe of her one to ba fiery ■

Fig. 11. — Diagram showing Principle and
Connections of Electric Trembling Bell

clean, and give the minimum of trouble. You will choose
a nice dry situation- but not a hot one. The contents
of this type of cell are really moist, not dry, and if you
put it in too warm a place such as over a stove, or near a
chimney breast, it might soon fail, as a result of evapora-
E 49

Every Boy His Own Mechanic

Dther termmal to be
-connecred To push and ■
the other one to battery

tion. It is better to get a box that will take it just com-
fortably and protect it from the atmosphere, and from
your brother's prying fingers. If it is for a bedroom light,

perhaps the box can go
on a shelf, and be
hidden by some books,
or possibly room can
be found for it in a
cupboard, but not a
damp one ; it gener-
ally happens that small
holes will have to be
bored in the woodwork
to allow the wires to
pass. As only a few
yards of the conduct-
ing wire will be wanted
— the shorter the run
of wire the better — your
best plan will be to
buy the best insulated
electric-bell wire (Stan-
dard Wire Gauge, No.
16), and connect a
length with one pole
or terminal of the
battery. To allow of
slight adjustment of position, and to prevent vibration
causing the wire to be disconnected, it is usual to form the
last few inches of the conductor into a spring by winding
it round a lead pencil, and then removing the pencil.

Fig. 11a. — Diagram showing Principle and

Connections of Electric Single-stroke

Bell

Erecting Electric Lamps and Bells

Doubtless you have seen it hundreds of times when ex-
amining electric bells. You have now to decide the
positions of the lamp and push or switch.

In many of these arrangements I am now going to
describe you can use either a bell or a lamp, providing
that the battery is sufficiently powerful. You can easily
prove by simple experiment that a little flash-lamp battery
will ring an ordinary electric-bell quite vigorously, but
not for long. A quart-size Leclanch^ cell will ring a
bell or light a miniature lamp for a second or so at a time
at fairly long intervals over a period ^^^^^^
of a year or more. "N^^^g^^^

How an Electric Bell Works. — Per- '^^^^^^

haps I had better make it plain how a ^^m ^^

bell works. It consists, as in Fig. 11, ^^P\^^

of an electro-magnet d, a contact maker ^^^^^^^

and breaker e k J, an armature and ^'^^^^^^

hammer g h, and a gong n. The electro- f^^; sp^rlTgs tf Jsin
magnet is two cores of soft iron wound ^"^^

with fine wire. Its poles F attract the armature and
hammer only when current is passing through the coils.
Immediately the armature is attracted and the gong in
consequence struck by the hammer, the circuit is broken,
current no longer flows through the coils, and the armature
is released, only to re-establish the circuit again, ring the
bell, again " unmake " the circuit, and so on. You can
follow the passage of the current from terminal a, through
spring c to coils d, then to the insulated contact pillar e,
platinum contacts k, spring J, and thence by means of
the metal frame l (indicated by the stipple lines) and
through wire m to the terminal b. The above is an

5«

Fig. 13. — Vertical sec-
tion through Bell Push

Every Boy His Own Mechanic

ordinary " trembling " bell, a type that does not work
well when connected in series with a similar bell. For
series working, one trembling bell and the rest single-
stroke bells (Fig. 11a) should be used ; in the latter, there
is no " make-and-break " effect.

A Simple Circuit. — You wish to
light one lamp or ring one bell at
pleasure from a push. This is the
simplest of all electrical arrange-
ments, and has already been shown
in Fig. 4. Put the lamp or bell in the required position.
From one terminal run a wire a to the battery. (In
electrical diagrams the usual symbol for a battery is
nil). From the battery's other terminal run a wire c
to the push, continuing with wire b from the second
terminal of the push to the remaining terminal of the
lamp or bell. Fig. 4 shows a bell, but the diagram is
equally correct for a lamp.

The push is simply a little device for momentarily
" making " or " completing " the circuit.
It contains two springs, usual patterns
of which are shown in Fig. 12, and the
wires are connected individually to them.
Normally these springs do not touch one
another {see the section, Fig. 13), but
they are made to do so when the little
bone or ivory knob is pressed in, thus
completing the circuit. A push is better
on a miniature lamp system or for bell work than a
switch (Fig. 14), because with the latter you may be
tempted to leave the lamp or bell at work for too long

Fig. 14.— Simple
home-made One-
way Switch

Erecting Electric Lamps and Bells

Fig. 22. — Making Joint in Electrical Wires

Suppose that the gas-pipe connection is out of the
question, and that the electric bell is in your workshop
at the foot of a long garden and the push is in your house,
the bell being used to summon you to meals. You can
still dispense with a second wire. At each end of the
system bury at about 4 ft. or so some old waste piece of
metal — an old clean oil-can or a leaky galvanised iron
bath — and make good electrical connection with bell at
one end of the circuit and push at the other. Pack round
it some coke or
gasworks breeze,
and there you
are ! But you need
a rather damp
soil to give good
conductivity.

Joints in Elec-
trical Wires. —
You will need to
know how to
join two electrical wires together. For purely tem-
porary purposes simple twisting together is good enough.
For permanent work, bad joints must never be
allowed, since they oppose resistance to the current and
waste it. Moist air soon corrodes exposed joints. First
scrape off the covering, clean the ends of the wires with
emery cloth, cross them and wind one round the other as
in Fig. 22. Smear with " Fluxite," and use stick solder
or coat with " Tinol " instead, applying heat with a bit
or a Bunsen or blowpipe flame. In the case of branch
joints (T joints), the connection is as shown in Fig. 23.

57.

Fig. 23. — Making a Branch Joint

Every Boy His Own Mechanic

In all cases after soldering, replace any of the old insula-
tion if this is possible, or, instead, wind on prepared
rubber tape smeared with rubber solution, finishing with
paraffined cotton. All these insulating materials are
obtainable from the electrical dealers.

If the Bell Fails. — Faults in electric bell systems
often necessitate the use of a galvanometer for their
detection, an instrument which not every boy mechanic
is likely to have, but in simple systems of the kind which
I have described in this chapter, providing that the wiring
is erected carefully and in a common-sense way, there
should be an entire absence of line faults, and what troubles
may occur will be due rather to exhausted batteries,
defective bells, and loose or dirty connections. If the bell
rings sometimes and will not ring at others, you may sus-
pect a loose connection somewhere in the system, and
you may look for it especially at pushes, switches, and the
bell. The scraping of contacts — especially the " platinum' '
contacts in the bell — with a knife or rubbing with a
piece of emery cloth often works wonders on old bells
and other fittings that have been in damp places. Many
fittings contain a lot of brass, and brass is very susceptible
to damp. Corroded brass always gives trouble electrically.

If much trouble from damp is to be feared, take time
in the first place to make really good contacts between
the wires and fittings, and then touch the connections
with vaseline, which will defy the damp for a long time.

The use of flexible cord or cable is a great convenience,
both for bell and model light work, but the tiny wires of
which the cables are composed cause trouble if one or two
are left loose ; thus one tiny wire projecting from a con-

Erecting Electric Lamps and Bells

nection may easily cause a most baffling occasional
ringing, and will exhaust the battery.

In the course of time the battery will need renewal. If
a wet Leclanche is in use the re-amalgamation of the zinc
and the renewing of the sal-ammoniac solution will often
work wonders, but in the case of a very
old battery it may be necessary to renew
the porous pot as well. But do not rush
to the conclusion that the battery is
at fault until you have examined the
system in its every detail.

Wiring up a Lampholder. — The
lampholder to receive miniature lamps
may have a cord-grip or a flange as
shown respectively in Figs. 24 and 25.
Flanges are for use on battens, etc.,
and the wires need to be conducted, to
the terminals, behind the flange which is
screwed to its support. The cord-grip
holder is more generally convenient,
as it may be suspended with a minimum
of trouble exactly where it is wanted. It
has a cord-grip D (Fig.24) which takes the
weight of the holder and lamp off the
actual terminals, thus preventing a fall of the lamp through
the failure of the connections. The milled ring c holds the
brass body to the porcelain interior, and the milled cap b
supports a shade, whilst a is the cyhndrical part or socket
in which is the well-known bayonet slot to receive the
lamp. Inside the brass body above ring c is the porcelain
fitting with terminals to receive the two ends of the circuit

Fig. 24.— Cord-
grip Electric
Lampholder

Fig. 25.— Flanged
Electric Lamp-
holder

Every Boy His Own Mechanic

wires, the last-mentioned being bared of their insulation
only just sufficiently to allow of their being clamped or
pinched tightly into place. The terminals have little
plunger contacts at the bottom which make flexible con-
tact with the actual lamp terminals or with crescent-
shaped brass plates in the lamp socket.

Now in wiring up such a lampholder, the parts are,
threaded in the following order : First the cord-grip,
then the brass body, and then the porcelain interior ;
the milled rings and socket containing the bayonet slot
can be put on afterwards. The bare wires pass through
holes in the porcelain body, and are held by the screws
in the terminal blocks. Be careful when you are using
flexible cable, which, as I have explained, consists of a
large number of very fine wires, that no odd wires stray
across to the opposite terminal, or even touch the metal
sides of the lampholder, and so cause a short circuit.
The bare wires having been connected, all surplus must be
cut off close to avoid risk of short-circuiting. Then
bring together the brass lampholder and the porcelain
fitting, and screw on the milled ring which holds them
together. The cord-grip contains two wooden fittings
which are now to be put in place, taking care that they
fit into the little groove which prevents their being
twisted when the cord-grip is screwed down. The grip
wedges the fitting to the support wires, and, as already
stated, relieves the actual electrical connection of any
strain.

To put on the lamp shade it is generally necessary to
invert the holder. Then the shade can be carefully in-
serted over the screw threads, and the second milled ring

Erecting Electric Lamps and Bells

or cap screwed on to hold it in place, but do not screw it
up very tightly, or you may crack the glass shade.

Attaching Wires to Walls, etc. — You may need a
word or two with regard to the method of running the
wire for a permanent job, but you will not forget my advice
to get the best wire you can afford. Primary batteries
easily run down if there is a small leakage anywhere,
and leakage easily occurs when insulation is defective.
Therefore, when putting up wire for a model lighting or
an electric bell system in your den or workshop, and
particularly if the wire has to cross places which are sub-
jected to dampness, you would do well always to use wire
having at least a rubber and double-cotton covering. A
single-cotton insulated wire is all very well for temporary
use in a dry situation, but not for much else. If you are
putting up a system which is expected to last for years
and the wires cross an open garden, you ought to use
nothing inferior to a double-rubber or even a vulcanised
rubber insulation. For a little system installed in your
bedroom or den which will not be subjected to dampness,
quite a cheap form of insulation will be good enough.
But use nothing smaller than No. 16 gauge wire, remem-
bering that the smaller the cross-section of the wire, the
greater is the resistance opposed to the passage of electric
current, and the less useful effect will you get. The
circuit from battery to lamp or bell should be as short
and direct as possible, for every extra foot of wire intro-
duced means extra resistance for the current to overcome
before it can start to do any useful work for you.

If the wire has a proper insulation no more elaborate
method of running it need be adopted than that of simply

Every Boy His Own Mechanic

securing it to the woodwork by means of staples, but do
not drive them too far home, as the very first thing to
be remembered is that the insulation that covers the
wire must on no account be damaged. For instance, if
the two wires carrying current to and from a lamp or bell
be placed under one staple, and you drive this home in
such a way as to injure the insulation, the staple will form
part of the circuit, which will now be " shorted." The
lamp or bell might get a little current, but not much,
and in the event of the push or switch being between the
staple and the lamp, etc., your battery will rapidly exhaust
itself. Ordinary wire staples can be used with care, and
you can introduce a tiny scrap of old inner tube or any
similar insulating material just under the head so as to
minimise the risk of actual metallic contact between
staple and conductor. Or you can obtain from the
dealers special insulating staples, just as you please, or,
better still, you can use a twin flexible cable and run it
through insulated screw-eyes. This " twin-flex " is two
cables twisted together, each consisting of a number of
fine wires.

The professional electrician runs wires through walls,
floors and ceilings, but that is a proceeding which I do
not advise the boy mechanic to attempt unless he has
full permission to do the work, and also is perfectly sure
before he starts as to what he proposes to do, how he will
do it, and that in the course of the job he will not cause
much unnecessary injury to the building. My firm advice
is not to cut holes anywhere unless it be in a garden shed
or workroom of rough construction where a few holes
will do no particular harm. Wires are never drawn

Erecting Electric Lamps and Bells

through the rough holes cut in brickwork, but for all such
positions should be encased in metal piping. Holes are
frequently cut in wood partitions by means of long gimlets
(electricians' or wiremen's gimlets), and if care is taken to
see that the holes are perfectly smooth, and that the wire
is well insulated and not drawn too tight, I see no reason
why for bell work or model lighting you should not dis-
pense with tubes in such places. Generally avoid cutting
and drilling, and run your wires wherever possible in such
inconspicuous positions as the tops of cornices, picture
rails, and skirtings, under window sills, etc. Sometimes
you can run your wires up pipes to which you can secure
them with little clips in the form shown in Fig. 21, or, as
already described in this chapter, you might make the
pipes themselves part of the circuit and simply connect
the wires to them, using the same clip, and seeing that
both pipe and wire are perfectly clean and bright so as to
get good electrical contact. You can even dispense with
clips by binding the circuit wire to the pipe by means of
three or four turns of fine wire, everything being bright
and clean as before.

It saves much time and trouble to employ the twin
flexible cable already mentioned, insulated with rubber
and cotton, or, better still, rubber and silk, and simply
to run it through insulated screw-eyes which are obtainable
from all electrical dealers. A great advantage of using
these special eyes, either closed or open, is that the wire
is kept clear of the surface, and is therefore far less affected
by any dampness which may be present in the walls or
ceiling. The screw-eyes can be inserted at suitable places,
and nothing is better and likely to do less damage than

Every Boy His Own Mechanic

this method. The only difficulty may be in the case of
ceilings, as unless the screw enters the lath behind the
plaster, no fitting depending on it will be safe. Unless a
slight discoloration shows the difference between the
laths and the spaces between them, there is only one way
of determining their position, and that is to probe in one
or two places with a very fine sharp awl. When the
screw-eyes are used, the flexible cable will need to be
drawn very carefully through them, unless you go to the
expense of using the sort with open eyes. These are
very convenient, as all that is necessary is to lay the
flexible in them and give the porcelain part a turn so as to
close the eye.

THE HEKTOGRAPH COPIER: HOW TO
MAKE AND USE IT

I WELL remember when I was a small boy making a jelli-
graph of my own invention, and thereby earning the sum
of one halfpenny as profit, the writing out of a sheet of
instructions on using the copier being thrown in gratis.
Did I but know it, I ran the risk of an action for infringe-
ment of patent rights, because at that time the hektograph,
as the jelly copier is called, was the subject of a patent
which did not expire until 1894. The jelligraph I invented
consisted simply of one pennyworth of glue with, I think,
a little moist sugar added, and it worked quite well until
it dried up or went mouldy. It so happens that glue is
the foundation of the proper hektograph jelly. It ought
to be the best and clearest glue you can buy, and will be
in the form of hard cake, not cloudy, nor should it have a
decidedly unpleasant smell. If you can get the use of a
flat metal tray holding about half a pint of water, you will
need not more than 2 oz. of the hard glue, and as such
a small quantity is required you can just as well afford the
best as the worst. Wrap it in a piece of canvas, break it
up with a hammer, place the fragments in a basin, and
just about cover them with water. After a few hours
you will find that the glue has swollen up into a
jelly. Place this in an old clean handkerchief, or in a
F 65

Every Boy His Own Mechanic

piece of muslin, and squeeze off any surplus water. Borrow
a 2-lb. earthenware jam-jar, and in it place the glue jelly,
covering it with 10 oz. of glycerine. Put the jar in a
saucepan containing a small amount of water, and bring
the whole to the boil, afterwards allowing it to simmer,
and stirring it from time to time to be quite sure that the
glycerine and glue have combined to make a nice syrupy
solution. The object of adding the glycerine is simply to
prevent the glue drying to a hard cake and to allow of
its being melted up time after time without losing its

I moisture. Another ad-

Fig. 1.-

-Pattern for Metal Tray to
hold Hektograph

dition has now to be
made, this time for the
purpose of preventing
the composition going
mouldy. If you have
ever discovered a piece
of cake glue in a damp
cupboard, you will know
the state glue quickly
gets into if not kept in a dry and airy place. A few
drops of any essential oil — say, about ten drops of oil
of cloves — will be all that is necessary. You can often
detect the smell of oil of cloves in office pastes and similar
compositions. Stir the oil into the composition, and
straightway pour the contents of the jar into the tray
prepared for it, placing the tray on a perfectly level table
in a cool place until the jelly is set. I made the lid of a
biscuit tin serve my purpose, but something a trifle deeper
would be better. It is not difficult to make a tray at home
from thin tinplate cut out to the pattern shown in the

The Hektograph Copier

diagram (Fig. 1), and bent up on the inside lines, the
little extra pieces or lugs to be bent round the corners
where they will be secured with solder. Instructions on
soldering are given in another chapter. The bending of
the metal can be done over the perfectly square edge of a
piece of board. I have often seen in ironmongers' shopfy
trays costing only a few pence that would serve the
purpose splendidly.

I suppose you know how to use a hektograph ? Per-
haps your school magazine may have been " printed "
on such a device. The original must be written with a
certain kind of ink, which is best bought ready made,
but which, if you wish to do everything yourself, you can
prepare at home by mixing together 2 oz. of methylated
spirit, 2 oz. of water, and 4 oz. of glycerine, and adding
about I oz. of aniline dye. Aniline violet will do for the
blue- violet colour so common, aniline black for black ;
methyl green for green ; eosin for red, etc. etc. The
quantities given will make a good-sized cupful, which is
probably ever so much more than you will need, but I
don't think you can generally buy a smaller amount of
the aniline colour I have mentioned. I am told that
Judson's violet dye and Stephens' ebony stain answer
very well as hektograph inks ; but personally I have
never given them a trial.

You will find no difficulty in using the hektograph.
Gently stroke its surface with a soft, clean sponge, take
off any surplus moisture with a piece of fluffless blotting
paper or with a clean handkerchief, and then place the
written matter face downward on the jelly and gently rub
it into close contact with a handkerchief made into a

Every Boy His Own Mechanic

pad. Leave it for about three minutes, and then peel it
off by first raising it at one corner. To take a copy, simply
place a piece of paper in contact with the jelly, gently press
it into contact with the handkerchief pad, leave for a
moment or so, and peel off as before. The later copies will
require a much longer contact than the early ones.

It helps to preserve the margin of the jelly surround-
ing the transferred writing a (Fig. 2) from scratches, etc.,
if you lay down on the moist surface four paper strips
' B. A corner piece c just clearing the
written matter makes it easier to raise
the "printed" sheets.

The number of good copies obtain-
able will depend upon the quality
and quantity of the ink (by the way,
never blot the ink when writing the
original, but allow it to dry naturally),
and the care with which the hekto-
protecting surface graph lias been used, but it ought not
of Hektograph ^^ ^^ j^^g ^^1^11 about twenty, and is not

likely to be more than twice or thrice that number.

When the jelly is finished with, gently re-melt it in its
tray over a small peep of gas or in a slow oven, and remove
to a level surface to cool as before. In course of time the
jelly will become coloured with the ink absorbed, and its
appearance will be improved by mixing in a small amount
of very fine whiting.

A Putty Hektograph. — Some people think that the
" putty " hektograph is far superior to the jelly. It
certainly is more convenient in use, inasmuch as should
any accident occur to spoil the smoothness of its surface,

y. A

. .^.^i:

The Hektograph Copier

which in the case of the jelly would necessitate re-melting,
all that you need to do is to smooth it down again with a
flat piece of wood. Then, too, after the number of copies
has been taken, and you need to transfer or lay down
another original, all you do is to wipe the putty with a wet
sponge, blot up the surplus moisture with some fluffless
blotting-paper pressed into close contact, and the hekto-
graph is immediately ready for use again. It is a trifle
more troublesome to make. Get 1 lb. of the finest whiting.
You had better go to an artists' colourman and ask for
"gilder's whiting." First of all only half the quantity is
used. It must be in the form of a fine powder, and should
be thoroughly mixed with, and beaten up with, 8 oz. of
glycerine. Then leave it till the next day, by which time
some of the glycerine will have come to the surface. The
rest of the whiting, also in powder, should now be added.
It will not be easy to incorporate the whole thoroughly
well, but if you work at it in stages and put it aside for a
few hours, you will find that in due course the glycerine
will permeate the whiting. Finally, the mass will re-
semble dough, which will need to be placed in a tray and
rolled out perfectly smooth and flat with a ruler which
will run on the edges of the tray. The method of taking
the copies is the same as before.

Let me revert to the jelly copier and give a word of
advice. Materials vary, and the proportions given may
occasionally need to be altered. If the jelly appears to be
too soft, put it back into the jar and add a little glue, or,
instead, keep it at the simmer for some little while. On
the other hand, if the jelly gets too hard, re-heat and add
glycerine, gently simmering for a time as before.

INSERTING A WINDOW PANE

How often used I to watch a glazier at work and think
how easy the job was ! I have not altered my opinion
very much, but I know now that there were some things
about the job I did not know then. Amateurs and
especially boy mechanics, are so anxious to get the new

. .^ glass in position that

V J llii|||ii|^^ i[ij, i|| iiA •'

A L___l__i sufficient care to see

Fig. 1.— Hack Knife that every particle

of the old glass and especially of the putty that held it
is first removed. That, after allj is one of the secrets of
successful glazing.

Let me assume (I am drawing on my personal history)
that a cricket ball that never should have been " played
about " with so close to the kitchen window has made
a mess of one of the panes, and that you have offered to
repair the damage done !

To remove the old putty, you will need a hack knife,
and generally there is no need to buy the special tool
shown in Fig. 1. Most houses possess a table knife that
has been broken off short, and that will be the very tool
for your purpose. With that and a hammer, you can
cut out every morsel of the old putty. But be very care-
ful that you do not chip into the woodwork of the frame.

Inserting a Window Pane

You ma3^ come across a few brads, or tiny triangular
pieces of sheet metal which have been driven in flush with
the surface of the glass to assist the putty in holding the
pane in place. Remove them with pincers. Thoroughly
clean out the rebate or open groove until you are down
to the bare wood. If there is an undercut groove in the
top bar, take care to pick out all the old putty from it.
If the hack knife is not of much use there, try a thin
chisel, a bradawl, or a small screwdriver, but see that
the putty does come
out.

Next carefully
measure the rebate
size of the frame.
I may just remark
that every frame
that takes a piece
of glass {see Fig. 2)
has three sizes — the
over-all size ; the
sight size, that is, the measurement of that portion of the
frame or glass through which the light passes, and thirdly,
the rebate size, that is, the measurement across the frame,
including the rebates or open grooves in which the glass
lies. For example, a picture frame in front of me as I
write measures 16 in. by 19 in. over-all ; the sight size —
that portion of the glass which one can see from the front —
measures 10| in. by 13| in. ; the rebate size is 11 in. by
14 in., which means that the glass is resting in a rebate
about \ in. wide which has been made on the back inside
edge of all four pieces of the frame.

Fig. 2.-

-Diagram indicating the Three Sizes
of a Frame to hold Glass

Every Boy His Own Mechanic

NoAv if this picture-frame were a window-frame, the
piece of glass required to fit it would not measure 11 in.
by 14 in., the actual rebate size. A glass of such dimen-
sions probably would not go into the frame, but if it did
it would be far too tight, and in very hot weather when the
glass would expand, or as the result of any stress that
might come upon the frame, the glass would easily crack.
This, indeed, is the secret of those mysterious cracks
which occur sometimes in picture-frame glasses when a
room is unduly heated. So the piece of glass should be
I in. smaller each way than the rebate size ; in other
words, the glass will measure 10| in. by 13| in. Take
the exact dimensions to the glass-cutter, tell him what the
glass is to be used for, and he will give j^ou the right sort
and exact size.

Qualities of glass are known chiefly by the weight per
square foot, the thinnest being " 15 oz.," and a usual
quality being " 21 oz.," which is about y\, in. thick. For
fairly large panes, " 26 oz." glass is used, this having a
thickness of roughly | in.

The first thing to do in inserting the glass is to prepare
a bed for it by squeezing putty all round the rebate in one
even thickness. This is generally done with the fingers,
and there is nothing poisonous in glaziers' putty. Then
the glass is pressed into position, rubbing it near the
edges (not in the centre) with the fingers of both hands at
once. Of course, use as much care as possible, especially
if the glass is poor and thin. The pressure will cause the
putty to squeeze out at the back {see Fig. 3), and you must
continue the pressure until only a thin layer is left. If
the pane is of fair size, and there is any risk of its being

Inserting a Window Pane

blown out before the putty is hard, it will be as well to
insert a few fine brads, driving them in sufficiently far
that they will be covered by the facing putty when this is
applied. These l>rads can be driven in with an old chisel.
Sometimes professional glaziers use triangular pieces of
zinc, quite tiny

■. 4),
the

Fig. 3. — Glass
bedded in
Putty

Fig. 4.—

Zinc
Triangle

Fig. 5. — Section
showing Glass
and Front and
Back Putties

scraps {see Fi
instead of
brads.

The front putty
is now put in {see
Fig. 5), cutting it to
a nice bevel with
the putty knife
(Fig. 6) which may
be either a special
tool bought for the ^H- 6.— Putty Knife

purpose or a short stiff table knife. After this is
done, but not before, use the same knife to cut away
the surplus putty which has been squeezed through at
the back. It is as well to leave the pane untouched for
a week after completing the job.

VARIOUS WORKSHOP METALS: HOW TO
IDENTIFY AND WORK THEM

So many metals (iron, copper, aluminium, lead, zinc,
etc.) and alloys (steel, gunmetal, brass, solder, etc.) are
used in metalworking, that the boy mechanic may be
at a loss to distinguish one from the other. Even experts
find it difficult to tell some steel from some iron, and to
distinguish between certain qualities and varieties of
steel itself. Then again the alloys are legion, and only a
skilled metallurgist and chemist could identify some
of them from others. So I shall speak in this chapter
only of those everyday metals and alloys which the reader
is likely to handle in his home workshop.

Cast Iron. — This is a very impure iron obtained by
smelting iron ore. Pure iron does not exist in the
engineering workshop or in commerce. Indeed, it is the
impurities, sometimes, which give iron its special value.
Cast iron is harder than mild steel, but softer than hard-
ened steel, as to which I will give more information later.
The weight of a metal or alloy will be some guide in
identifying it, and in every case I will give the weight in
ounces per cubic inch. Cast iron weighs slightly over
4 oz. per cubic inch. It is very brittle, so much so that
dropped on a stone floor a cast iron article will generally
break. It cannot be bent, but can generally be filed,

Various Workshop Metals

chipped with a chisel, or sawn with a hack saw; but in
using a chisel, always remember that the metal may be
so weak that the whole of the casting may be broken
by a heavy blow. In cutting cast iron with a file a powder
is produced, whereas when wrought iron is worked, the
filings take the form of very small shavings. This is
because the cast metal is very brittle, and the wrought
metal tough and fibrous. Touch a piece of cast iron with
a drop of nitric acid, leave it on for a few minutes, wipe
off, and thoroughly rinse with water ; you will see a
dull black spot representing the carbon in the metal
which has been laid bare by the dissolving away of some
particles of the iron.

Wrought Iron. — This is refined cast iron, most of
the carbon and impurities having been removed by re-
melting, and it is usual for the wrought iron to be rolled
into plates, rails, bars, and rods. The weight of a cubic
inch is about 4| oz., but varies slightly. What a different
metal this is to the cast iron ! Its brittleness has vanished,
and in its place is a toughness which renders it, next to
steel the most reliable metal in the world. It is of a
fibrous nature (cast iron and steel are not), it can be bent
double without breaking, and it can be filed, sawn, drilled,
and chipped quite well, although its tougher nature makes
the work a little more arduous than is the case with cast
iron. In working wrought iron, you can use a lubricant
— either oil, or very soapy water. Tested with nitric
acid in the way already explained, you will reveal a dull
greyish spot, there being very little carbon in this metal
to be brought into prominence by dissolving away of the
iron particles. Wrought iron can be welded — that is to

Every Boy His Own Mechanic

say, two pieces of it made red hot can be hammered to-
gether to form one.

Mild Steel. — There is more than one way of making
mild steel, but the principle is to refine cast iron, add
carbon and put the metal through a process which actually
alloys the carbon with the iron. The steel is squeezed
out between rolls to the shape required. A cubic inch
of mild steel weighs about 4| oz. It is softer than most
other irons and steels, and like wrought iron it can be
easily bent cold, is weldable, and can be worked with
file, saw, and drill, although with greater difficulty, as it
is a tougher metal. Unless a file is rubbed with chalk
or oil it soon becomes " pinned " with either wrought
iron or mild steel ; that is, the spaces between the
teeth get filled up with the detached particles of the
metal.

Cast Steel or Too! Steel. — This is commonly called
crucible cast steel ; it is a " high carbon " steel, that is,
it contains a fairly high percentage of carbon actually
alloyed with the iron, and the result is to change the
whole character of the metal, which becomes quite
different from cast iron, wrought iron, or even mild steel.
It now has a property which not one of the materials just
mentioned possesses — it may be hardened by heat treat-
ment : Made red hot, and suddenly plunged into oil or
water, it becomes extremely hard and brittle. If it is too
hard or too brittle for the purpose in view it needs to be
heated to a temperature much below the first and then
either allowed to cool of itself, or plunged into oil or
water as before. This second treatment is known as
tempering, inasmuch as it has "tempered" the extreme

Various Workshop Metals

hardness. It is this ability to be rendered extremely
hard at the will of the worker that makes carbon steel so
useful. A tool made from it can be ground and sharpened
to a cutting edge, and the steel will be hard enough to
retain it, whereas a cast-iron tool would be broken the
first time the tool were used, and one of wrought iron
or mild steel would be turned up.

Tool steel is manufactured by melting some such
material as blister steel in a crucible and adding an ore
rich in carbon. The blister steel mentioned is itself
sometimes used for the making of inferior tools, and is the
result of heating cast iron and charcoal to a high tempera-
ture, the steel when cold showing blisters on its surface.
Cast steel is obtainable by the worker in the form of rods
and bars. It may be filed in its unhardened state, but
it is wise to use an old file for the purpose. Frequently
it is difficult to work tool steel unless it is first annealed,
a process which consists in slowly but thoroughly heating
the metal, and then burying it in cinders or ashes so that
it cools very slowly, this having the effect of thoroughly
softening the steel. The same lubricant as used for
wrought iron and cast iron (oil or very soapy water)
answers when filing, sawing, drilling, etc. As brittleness
always accompanies hardness, it is possible to break off
a piece from a steel bar or rod by first filing or chiselling
a nick all round, and then giving a blow with the hammer.
Very hard steel will scratch glass, so that you will quite
understand it is out of the question to think of filing or
sawing it, but until the hardness has been given it by the
heat treatment already referred to, it can be worked with
the ordinary cutting tools. A piece of tool steel tested

Every Boy His Own Mechanic

with nitric acid, as already explained, will show a
brownish black spot.

Copper. — This metal is obtained by smelting certain
ores and refining the product a number of times. One
cubic inch weighs about 5 oz. It is softer than tin or
zinc, and is very malleable, more so than iron or steel.
Filing, sawing- drilling, etc., are affected by the clinging
nature of the metal, but the work is all the easier for
using a soapy water lubricant.

There are many valuable alloys containing copper,
the strongest being phosphor-bronze, a mixture of copper,
tin, and phosphorus, capable of standing great wear, and
for that reason used in machines for bearing surfaces, etc.
Bronze or gunmetal is another very valuable alloy, con-
taining from 85 to 90 per cent, of copper and 15 to 10
per cent, of tin ; this alloy is fairly easily worked, but
as the percentages of the two ingredients vary so much,
it is not easy to give definite particulars. A cubic inch
weighs rouglily 5 oz. Brass is an alloy of 70 to 80 per
cent, of copper, with 30 to 20 per cent, of zinc, an average
brass weighing nearly 5 oz. per cubic inch, and being harder
than silver. Cast brass is softer than tin, but the drawn
brass is harder than that metal. Brass is very easily
filed, chipped, sawn, drilled, etc., but needs to be treated
cautiously owing to its lack of strength. Neither brass
nor gunmetal requires a lubricant in working. It is ex-
tremely important to work in a new file on brass, and
afterwards use it on iron and steel.

Tin. — This is a metal which is not often used alone.
It is obtained by smelting certain ores, and its chief use
is to alloy with lead to make solder, and to alloy with

Various Workshop Metals

zinc and copper to make babbit metal, which, being harder
than lead; but easily melted, can be readily moulded and
cast, and is commonly used as a bearing metal. Tin itself
is harder than lead, but softer than zinc, and a cubic inch
of it weighs about 4| oz. You frequently see in a book
some such instruction as " Take a sheet of tin and bend
it," etc. etc. What is meant by an instruction of that
sort is, take a piece of " tin plate," which nowadays is
thin mild steel that has been coated with tin to protect
it from attack by atmosphere and moisture. Tinning is a
very easy process, as any metal which has been perfectly
cleaned, and made hot, will take a coat of tin if brought
into contact with that metal ; see, for example, what
another chapter has to say with regard to the tinning of
a soldering bit.

Lead. — This is the softest of workshop metals, but a
very valuable one. It is extremely malleable, and will
go into almost any form when worked by a hammer.
It is so soft that it can be cut with a knife, which will
leave a bright metallic lustre. It is heavy, a cubic inch
weighing slightly more than 6| oz. Few acids have any
effect upon it, but either nitric acid or aqua regia (1 part
of nitric acid mixed with 2 parts of hydrochloric acid)
readily dissolves it. It is easily filed, but very rapidly
gives trouble owing to the clogging up of the file, for
which reason, a single-cut file {see p. 98) is preferable
to the ordinary double-cut file, this also applying to
solder, aluminium, and copper.

Zinc. — This is another useful metal at times, but is
chiefly used alloyed with copper to make brass. It is
of about the same hardness as tin. It is a bluish white

Every Boy His Own Mechanic

metal, and weighs about 4 oz. per cubic inch. Used in
batteries it requires to be amalgamated with mercury
{see p. 112).

Aluminium. — This is made in the electric furnace
and has proved to be one of the most useful metals ever
discovered. It is the lightest workshop metal, a cubic
inch weighing barely 1| oz. It can be bent and worked
without difficulty, a good lubricant being ordinary paraffin
oil or turpentine. A file is soon clogged by it. I mentioned
just now the ease with which metals are tinned, but
aluminium is the exception, and this accounts for the
great difficulty in obtaining a really satisfactory soldered
joint in this metal. Should you ever try to solder alu-
minium, get one of the special solders containing phos-
phorus, and use a bent copper bit by means of which you
can well scrape the solid surface before and while melting
the solder. Hot aluminium oxidises with extreme rapidity,
and immediately a film of this oxide forms it must be
scraped off and the soldering instantly proceeded with
unless the flux or the solder used has the property of
dissolving aluminium oxide. The phosphor solder has this
property, and when combined with the use of a bent bit,
gives undoubtedly the best results obtainable, short of
welding by means of the oxy-acetylene blowpipe flame.
Aluminium bronze is a useful alloy, this being made by
melting together either copper or bronze with 5 to 10 per
cent, of aluminium.

Expensive and Precious Metals. — Silver, gold and
platinum have valuable qualities from the metalworker's
point of view, but their expense prevents their being
generally used. Silver, however, is commonly employed

Various Workshop Metals

in soldering (see p. 135). It is harder than gold, but softer
than brass or tin, and a cubic inch of it weighs about
6 oz. Gold is the only yellow metal, and resists the action
of most commerical acids, although it is easily dissolved
by aqua regia, the proportions of which have already
been given. It is harder than lead, but softer than silver,
and its weight is about 11'16 oz. per cubic inch. Platinum,
which is one of the whitish metals, and is even harder than
gold, also resists the action of acids, even aqua regia
having only a slow action upon it. In hardness it is below
most qualities of drawn brass. It is extremely heavy, a
cubic inch of it weighing from 12 to 13 oz., according to
the preparation and treatment the platinum has received.
Its extremely high cost puts it beyond ordinary reach.

MAKING PICTURE FRAMES

One of the most useful and pleasurable jobs falling to the
lot of the boy mechanic is the framing of a picture. This
is a simple matter if the frame is already made and sup-
plied with glass cut to size, but I propose to show you in
this chapter how to do the work from the beginning.

Not that I shall go into the making of the moulding
from which the sides of the frame are cut. Few people

Fig. 1. — Sections of Picture-frame Mouldings

make their own mouldings nowadays. The manufacture
of composition mouldings is a trade to itself, and the
more desirable mouldings in oak, rosewood, ebony, etc.,
are seldom made nowadays with shaped plane cutters,
but instead are produced in length and with ease on a
machine known as the vertical spindle. This is a rapidly
revolving spindle to which is clamped a cutter block
containing four shaped cutters. The spindle revolves at

Making Picture Frames

a very high speed, and strips of wood are guided past the
cutters, which instantly remove the chips and produce
the moulding before your eyes. All sorts of mouldings
are obtainable at picture-frame supply shops, but take
my advice and for your early efforts use solid stuff, neither
veneered nor faced with plastic composition. Fig. 1
illustrates in section a few of the many patterns of solid
oak mouldings available. Flat gilt slips (Fig. 2) may be
used with simple mouldings of the kinds shown.

Equipment. — Your woodworking tools will be required

Fig. 2. — Sections of Gilt Slips
for Picture Frames

Fig. 3. — Mitre Box

in frame making, and, in addition, one or two special
appliances for cutting and finishing the mitres at the
frame corners. First these mitres are cut with a fine saw
— tenon or dovetail — and are then faced up with a keen
finely-set plane-iron, and for both of these jobs some
special device for guiding the tools must be adopted.
For sawing the mitres, either a mitre box or a mitre block
is necessary — preferably the former. It is a trough
(Fig. 3) across the top edges of which have been set out,
with extreme accuracy, two intersecting angles, each of 45°,
the lines being squared over on the sides as indicated.
A saw is then run down in two directions so as to form

Every Boy His Own Mechanic

slanting cuts, those on one side being, of course, in perfect
alignment with those diagonally opposite. Any good
odd stuff will do for the box, 1 in. being a suitable thick-
ness. After the box has been in use for some time, the
entrances to the saw cuts will become worn, to prevent
which a set of four pairs of iron guides may be bought
from a tool-dealer and screwed on. Very convenient
forms of mitre boxes are sold, and, in general, the
amateur is well advised not to make his first appliance of
this kind. The mitre block (Fig. 4) is on the same
principle as the box. and need not be particularly
described ; it is an alternative to
the other, but is not recommended
in preference to it.

Cutting the Moulding Lengths.
— Before cutting up moulding,
make a rough drawing of the frame
Fig. 4.— Mitre Block o^" frames required (it generally
saves time to make two or three
frames together), and be absolutely certain as to your
measurements. Remember that a frame has three dis-
tinct sizes (as explained on p. 71) — the over-all, rebate and
sight — and the picture and glass should be very slightly
smaller each way than the rebate size of the frame. A
little scheming will make for economy. A length of
picture moulding is usually about 12 ft. To estimate the
length of moulding required to frame a picture, add
together the lengths of the four edges of the picture
mount, add four times the width of the moulding, and
allow a trifle for cutting. Thus, a 12 in. by 10 in. picture
will require of 1| in. moulding :

Making Picture Frames

12 in.

12 in.
10 in.
10 in.
6 in. (1| by 4)

Fig. 5. — Mitre Shooting-board

50 in. ; add to this 4 in., an ample allowance — total,
4 ft. 6 in.

Thus a 12 ft. length of moulding would make two
frames of the rebate size above mentioned, and have a
surplus of 3 ft. or
slightly more.

It is Easy to
Cut the Moulding in
the Wrong Place.
— Moulding is ex-
pensive, and if cut thoughtlessly will often be wasted.
For cutting, hold it in box or block, and run down the
fine saw, using it lightly. Cut a long side first, from it
scratch off the length of the opposite member, and pro-
ceed to cut that. There will be trifling differences in the
lengths, I expect, but you can correct these when
" shooting " or finishing. Do the shorter sides last and
cut the pairs of sides for all the frames in hand before
proceeding further.

"Shooting" the Mitres. — The sawn edges or faces
are sufficiently rough and inaccurate to prevent all four
joints being of neat appearance when viewed from the
front. They have yet to be planed on a mitre shooting-
board, which is a device for holding the moulding in such
a position that a plane lying on its side and guided by

Fig. 5a. — One-piece Frame with
Ornamental Head

Fig. 5b. — Jointed Frame
with Bar

Fig. 5C. — Mitred Frame with Fretwork Ornament

Making Picture Frames

contact with the board may be " shot " across the sawn
face and caused to remove the saw marks. The mitre
shooting-board may be bought or can easily be made by a
careful amateur from f in. to 1 in. stuff, well planed and
perfectly parallel, by screwing a narrow board to a wide
one, as in Fig. 5, and then screwing on an equilateral
triangular piece (known as the fence) also as shown. The
edges of the triangle will make angles of exactly 45 deg.
with the front edge of the narrow board. The plane is

Fig. 6.

-Mitre Shoot In use ; showing also how to set the
Fence with help of Set-square

used on its side, edge of cutter towards the triangle {see
plan of a different pattern of shooting-board, Fig. 6),
and will need to be in perfect condition, the cutter being
very keen and projecting only slightly. For shooting
joints, the cutter needs to be sharpened like a chisel,
quite square or straight {see p. 21).

A still simpler mitre shoot which anybody can make
for himself is shown in Fig. 8. It is a wide piece of wood,
A, with one edge planed straight, screwed down upon
it at an angle of 45° with the edge being a wooden

Every Boy His Own Mechanic

strip — the fence. The angle
line can be set out with set-
square or bevel-square.

To use a mitre shooting-
board, lay the moulding
down face uppermost and
with its outer side (not the
rebate side) in close contact
with the fence, the sawn end
just projecting over so that
the plane, worked by the
right hand while the left
holds the moulding, will

Fig. 7.— Small One-piece Frame for merely clean off the rough-
staading or hanging

ness and nothing more. Do
both of the ends, of course, then proceed with the other
pieces, and again compare and check the lengths of
opposite pieces, placing the rebated edges together for the
purpose, and effect any correction necessary.

You will see in the tool catalogues quite a number of
special tools
and appliances
for frame mak-
ing. I can only
say of them
that the profes-
sional frame-
maker leaves
most of them
alone, but there

is one that is Fig 7a. — Another simple One-piece Frame

Making Picture Frames

coming more and more into popularity, and that is the
mitre trimmer, cheap patterns of which are now available
for amateurs' use. The sawn moulding is put into the
trimmer, a lever pulled, and a keen chisel-edge takes a
light cut over the mitre and effects a great saving in time
as compared with the use of plane and shooting-board.

Gluing and Cramping. — The mitred members are
now to be joined together with glue and nails, and I will
explain just one Avay, and that the simplest, in which this
may be done. Four corner blocks (Fig. 9) for each frame
will be wanted. They can
be cut with a turn or com-
pass saw from thick wood,
or, more easily, sawn off
from a circular piece of
stuff 2 in, or more in dia-
meter. Cut out the square

Wfl

. Fig. 8. — Simple form

notch to receive the frame I ,' of Mitre Shoot

corner, and cut one or two ■■ *

string grooves with a saw as shown, finally cleaning the
whole up with glasspaper to remove any roughness that
might abrade the string used in tightening the joints.
Build up the frame on a sheet of newspaper covering a
bench or table, and put a block a (Fig. 10) at each corner.
Pass a length of strong smooth string b round the whole
two or three times, and tie the ends securely. Get four
short sticks c, insert them between the strings and twist
several times so as to tighten the string and puU the
joints close together, as in Fig. 10. If they go right home
and the work needs no further correction, loosen the string,
remove the mouldings, coat the joint surfaces with good

Every Boy His Own Mechanic

hot glue, replace, and again tighten up, leaving all night
for the glue to get hard. Apply the glue smartly, and
have the mouldings fairly warm in readiness. If the
frame is of any size., strengthen each
joint next day by inserting a fine nail or
screw from the side {see Figs. 11 and 12),
or by gluing in one or two pieces of veneer,
as in Fig. 13, first making a saw-kerf, as
at A, inserting glued veneer, as at b, and
cleaning off when dry and hard.

Plenty of special frame cramps are
obtainable at dealers', but the one here described costs
almost nothing and is quite efficient.

Fitting Up a Frame. — Next we will proceed to fit
up a frame with glass, picture, backboard and screw-eyes.
You will probably get the glass cut to size, ^2 ^^' l^ss each
way than the rebate size of the frame. But if you cut it
yourself with diamond or v/heel glass-cutter, see that it is

Fig. 9. — Corner
Block for Picture-
frame Cramp

Fig. 9A. — One-piece Frame with Oval Opening
90

Making Picture Frames

bedded perfectly flat upon a freshly-dusted table top
on which a newspaper has been spread, and use the
instrument with steady uniform pressure ; otherwise you
are almost certain to crack the glass. All that the diamond
or wheel-cutter does is to scratch the surface, and the glass,
being very brittle and weak, easily parts at the scratched

Fig. 10. — Cramping Picture Frame with Corner
Blocks and Twisted String

line. A fine file can often be converted into a cutter for
common qualities of glass. It must be " glass-hard," and
can be made so by heating in a fire or blowpipe flame to
bright redness, and immediately plunging into cold water.
It will now easily break, leaving extremely sharp edges
which can be used exactly as a diamond. They wear
rapidly, but a new cutting point is easily made by
breaking off a further piece.

Every Boy His Own Mechanic

Fig. 11. — Nailed Frame Joint

The cut glass should be well cleaned, and personally I

have always used methylated spirit, which dries quickly

and leaves a bright polish ; but you can do quite well

without it.

The backboard of a frame
is thin, rough-sawn and often
faulty stuff, which can be
bought in lengths of about
6 ft. and in widths up to
12 in. It will need to be
sawn or cut with a knife or
chisel to size. The rebate
in the frame should be deep
enough to take glass, pic-
ture and backboard, but it

often proves to be too shallow, in which case the

margin of the backboard must be bevelled, as shown in

the section (Fig. 14), to permit of the headless tacks or

sprigs being inserted.

I find that the best

means of diiving in

the sprigs is an old

chisel used flat, so that

its side near the point

acts as a hammer, and

I place a flat iron on

the bench or table

against the frame so that its weight is added to tliat

of the frame and makes the nailing easier.

Smoke and dust have a wonderful way of working

into a frame, and it is always wise to cover the whole of

92'

Fig. 12. — Screwed
Frame Joint

Fig. 13.- Keyed
Frame Joint

Making Picture Frames

the back with a sound piece of brown paper pasted on at
its edges. To make assurance doubly sure, you can first
of all paste on 2 in. strips of paper to hide the rebate
and any joints in the backboard [see Fig. 15), afterwards
covering all with one piece.

Fig. 14. — Section of

Fitted Picture Frame

showing Bevelled

Back Board secured

with Sprigs

C ,•

Fig. 15. — Paper Strips pasted over
Cracks to exclude Dust

Screw-eyes or screw-rings need to be inserted to com-
plete the job, first boring little holes for them, but making-
certain that the screws do not come through to the front
of the frame. Special cord for picture frames is sold,
but I prefer wire, which is finer and neater. Brass wire
'soon corrodes, but gilt copper wire will last a long time.

HOW TO USE METALWORKING TOOLS

Bench and Vice. — Most metalworking demands a heavy
bench or table, but perhaps you can make do with a
small rigidly-built table with a 2-in. thick plank laid
on it to receive the roughest of the wear. A vice of some
sort is a very great convenience. You can get along

Fig. 1. — Heavy form of Bench
Vice with Parallel Action

Fig. 2. — Table Vice, fixed by
Turnscrevv from underneath

without one, but not easily. The heavier and stronger
th vice the better it will be, but a small vice is better
than nothing. I give in Fig. 1 a diagram of a good solid
type, and you can look up prices and pictures of other
sorts in almost any tool catalogue. A leg vice that,
besides being attached to the bench, actually rests on the
floor, is an advantage, particularly when the bench is too
slight to stand much heavy work. Fig. 2 shows a type
often favoured by amateurs.

How to Use Metalworking Tools

Hack Saws. — Immediately we start to do any metal-
work, however rough and simple, we notice the particular
need of saw and files. A hack saw is a very hard steel
saw with fine teeth, and it is used for cutting brass, copper
and even iron and steel. The saw itself is a blade held
in tension by a frame, one of the simplest kinds being shown
in Fig. 3. In this, after the blade is inserted, the winged
nut on the outer end has to be turned until the saw is

Fig. 3. — Cheap Cast-Iron Hack Saw Frame

Fig. 4. — Sleeve-adjusting Hack Saw Frame

taut. A saw that I have found very convenient is a
cheap pattern, the length of which is adjustable (see
Fig. 4). The two clamps are first placed in position,
the saw threaded over the two pins which the clamps
carry, and the wing nut then given two or three turns as
may be necessary to make the blade tight. A better kind
is adjusted entirely from the handle. You will note
directly you get a hack saw into your hands that the
blade can be set for cutting either downwards or upwards,
or even sideways, either to the left or right. It is well to
remember this, as the ability to use the saw sideways is
often an advantage. Get the best saw blades you can

K -^"A

Hot

Hand Knife

o a A

Round Sq. 3 comer

Fig. 5. — Sections through
various Files

Every Boy His Own Mechanic

afford, and remember that as the saw cuts on the forward

stroke, the teeth should point away from the handle.
Do not apply too much pressure
when using it, and push it neither
too fast nor too slow.

On copper and the various
copper alloys for which a saw
with twelve teeth to the inch
is roughly correct, the speed of
working should be about a double
stroke every second, whereas on
iron and steel, for which the

teeth must be very much finer (about twenty to

the inch), little more than a single stroke a second

would be enough, but it is not only the speed that

counts, the right method of holding the saw is

a great factor.

First see that

the work is

supported at the

right height for

you. It should

be very slightly

lower than your

elbow when you

stand up. The

handle of the

saw is gripped

in the right Fig. 6,— Various Files : A, Flat ; B, Bellied
, , 1 •! J.1 Flat ; C, Square ; D, Triangular or Three-
hand, while the cornered; E, Round; F, Half-round; G,
left hand holds Knife-edge

How to Use Metalworking Tools

the front of the saw frame and not only assists it
to and fro, but holds it down to its work.

Files. — These are of various kinds, and you can spend
a lot of money on them if you want to, but don't. Make
do with as few tools as possible. In Figs. 5 and 6 I
show a few of the shapes with their names. Files are
made in three grades, known respectively as bastard.

Fig. 7. — Position for Filing

second-cut, and smooth, and, as a rule, the second and
third kinds, from 6 in. to 9 in. long, best suit the require-
ments of the boy mechanic. A convenient shape is the
flat tapering, the three-cornered or triangular file always
comes in useful, and perhaps the next best choice is a
half-round. By the way, in Swiss files six different cuts
H 97

Every Boy His Own Mechanic

can be obtained instead of the three in English ; and
numbers three and four will be found generally useful.

Some files are single-cut, and others double-cut,
that is, in the second two series of teeth have

been made in the file,
other. The single - cut
and alloys of a soft

Fig. 9. — How File Is held for Heavy Work

Fig. 10.— How File is held for Light Work

one at an angle to the
file is best for metals

clinging nature, and the
double - cut for
iron, steel and
the harder
alloys, such as
gunmetal, bronze
and high quality
brass . Fig. 7
shows you the
proper position.
It is so easy to
get a rounded
surface when
filing, the work
rising up in the

Fig. 11.— How File is held for Draw-filing middle and fall-

ing away at the edges. The right hand wants to
drop, the left hand to rise, and you have to correct
this tendency, and put in a lot of practice before
you can get a flat surface by filing. Figs. 7, 9 and 10
show how to hold a file, whilst Figs. 8 and 11 show the
positions of body and hands for di'aw-filing, the best
method of dealing with long and narrow surfaces;
the file should be chalked slightly and drawn over
the work.

How to Use Metalworking Tools

A test often given a mechanic when entering a new
workshop for the first time is to file up a piece of steel
flat and square. It is ever so much more difficult than
you think.

Scrapers. — I do not suppose that you will do much
scraping of metals, but should you be a model engineer
and attempt any serious work, you will have to know
how to prepare two pieces of metal so that they will work

Fig. 12.— Flat Scraper

Fig. 13. — Triangular Scraper

Pig, 14.— Good and Bad Shape of Triangular and Flat Scrapers
respectively

over one another and yet be so close together as to resist
the passage of steam under pressure. Just as filing
smoothes a surface produced by the use of the saw, so
the scraper makes still smoother a surface as it comes
from the finest of files. There are countless shapes of
scrapers, but a lot of useful work can be done with the flat-
ended and triangular shapes (Figs. 12 and 13). The first
has a slightly-rounded edge and can be bought ready
for use or may be made from a worn-out file of the right

15. — How the Fiat
Scraper is held

WEOOE.

Every Boy His Own Mechanic

shape by first annealing it {see p. 77) and then on a wet
grindstone grinding off the teeth, afterwards bringing up
the edges on an oilstone. It must be made extremely

hard by heating to bright
redness and cooling in
water. Scrapers are used
with short forward
strokes, not more than
in., and the tool is
grasped in the two hands.
The angle at which the tools are used is shown in
Fig. 14.

Hammers. — I hardly suppose you will go to the ex-
pense of a separate hammer
for metalwork, but remember
that "any old hammer" is
sometimes a danger, both to
you and the work. It may
badly mark any metal on
which it is used forcibly, and
should it be used to propel
a chisel or a punch, it might
easily glance and bruise your
hand. Three engineers' ham-
mers are shown in Figs. 17 to
19. Do you know the right
way of securing the head to
the shaft or handle ? With a
really sharp knife, lightly pare the wood to the correct
shape until head and handle are a tight fit. Separate
them, and make a saw-cut down the handle across the

Saw- CUT

HAMM&R, SHAFT

Fig. 16. — Wedging Hammer
Head on Shaft

(Hammer shown is the Woodworker's
"London" or "Exeter" Pattern)

JOO

How to Use Metalworking Tools

greatest width (see Fig. 16). Drive the shaft into the
head again, and have ready a wedge of hard wood, and
drive this into the saw-cut. Some people use an iron
wedge, which holds very well for a time, but ultimately
rusts, and then the head is liable to fall off. Soaking a
loose hammer head, with the shaft in position, in water
tightens the head.

Fig. 17.— Ball-paned
Hammer

Fig. 18. — Cross-paned
Hammer

Fig. 19.— Straight-
paned Hammer

Chisels. — Expert mechanics can do a great deal on
iron and steel with a hammer and chisel, and you will
find it worth while to emulate them to some extent. A
small casting, for example, that you may be working up
will probably need grooves and recesses cut in it which
would mean a lot of troublesome work with a file. There
are flat chisels (Fig. 20), straight-edge chisels, wide and
narrow, cross-cut chisels, and diamond-point chisels
(Fig, 21), and for cutting grooves the last-named will
be useful. The chisel edge will not have the keenness
of a wood chisel — 30° for brass and copper, 45° to 50°

lOI

Every Boy His Own Mechanic

for most iron and mild steel, and 65° for hard steel. You
remember that a plane-iron is slightly rounded at the
corners to prevent its digging into the wood. Well, a
metalworker's chisel of any width is treated in just the
same way {see A, Fig. 20). With such a chisel less metal
is cut at a time certainly, but the work is easier.

Drills. — For making holes in metal there are two
distinct methods. Iron and steel can be made red hot
and holes then punched in. That is the blacksmith's

/C=^

(<FvS

Fig. 20. — Flat Chisel Fig. 21. — Diamond-point Chisel

method. The engineer's method is generally to drill the
hole, and the boy mechanic will find one or at most two
types of drill bit enough for his purpose. The simplest is
the flat or diamond-pointed drill (Fig. 22), A more
efficient type is the twist drill (Fig. 23) obtainable in
scores of different sizes, but beware of applying great
pressure to the small ones as they are easily broken, for
which reason at first it is better to use the shorter kind.
These twist drills work very well on iron and steel and
hard metals generally, but not so well in brass, in which

I02

How to Use Metalworking Tools

there is always the risk of the drill seizing and breaking
unless it is frequently lifted out and the hole cleared.
Better than the twist drill for brass is the straight-
fluted drill (Fig. 24), but in this the waste does not
automatically rise out of the hole, and frequent removal
is necessary.

There must be some means of rotating the drill bit,
and in the case of the small sizes an archimedean drill
(described on p. 165) is the most handy, but a much more
rapid tool is a hand-drill or a geared breast-drill, or even
the familiar brace. But remember not to apply a great

Fig. 23.— Twist Drill

Fig. 22.— Flat Drill

Fig. 24.— Straight-fluted Drill

deal of pressure, especially in drilling holes in sheet metal,
more particularly with twist bits, which have a way of
screwing themselves through the metal in a moment.
As a start for the point of a drill it is usual to make a
light dent with hammer and centre-punch. In the
ordinary way brass may be drilled twice as fast as mild
steel and cast iron.

The right lubricant makes all the difference in drilling
metal. It means better work and assists in keeping the
drill in order {see pp. 75 to 80).

103

Every Boy His Own Mechanic

A hole that is slightly undersized is enlarged, not by
means of another drill, but by means of what is called a
reamer (Fig. 25). A rough reamer for holes in thin plate
stuff is the tang of a file, or even a tapering file itself.
Special tools are sold for the purpose, and should you ever

Fig. 25. — ^Reamer or Broach tor use in Brace
or Hand-drill

want one you will find a variety illustrated in almost any
tool catalogue, but for simple work in bent iron, for
example, a file tang is all you will need.

The Lathe. — The metalworker's most useful tool is a
lathe, but of such importance is it that I propose to have
it treated by my friend Mr. A. Millward in a separate
chapter.

104

FILING AT THE VICE

[Work IS slightly too lo-w for comfort and efficiency)

GLUE : HOW TO PREPARE AND USE IT

Not many people^ except craftsmen, know how to use
glue. They seldom prepare it in the proper manner, and
generally use it far too thick, not hot enough, and too
generously. The strongest glue joint contains only a
small amount of glue, and this exists in the form of a thin,
tough film in intimate contact with both of the pieces that
are joined together.

There are three things to remember : get the best
glue, have the wood properly prepared to receive it, and
do the work in a warm atmosphere. Very strong glue is
made by mixing equal parts of Scotch and French. Wrap
the pieces in a piece of sacking or in plenty of newspaper,
and break them to fragments with a hammer. Put them
into a gallipot or into the inner vessel of a gluepot, and
pour in enough water to cover. After the lapse of several
hours the glue will have swollen up and have absorbed all
or the greater part of the water, any surplus of which
should be drained off. Put the gallipot into a saucepan
containing enough water to reach half-way up the outside
of the pot, or, if you are using a proper gluepot, don't
forget to pour some water into the outer vessel.

I do not propose to take up space by describing
gluepots and brushes. You can get a small glue-
kettle (Fig. 1) quite cheaply (it is a double kettle, as

Every Boy His Own Mechanic

in the section, Fig. 2, the outer one for water and the inner
for glue), and a suitable brush for a trifle. Some people
prefer to make their own brush by hammering out the
end of a piece of cane {see Fig. 3). Over a gentle flame

slowly raise the glue to
boiling point, and main-
tain it at this for
about half an hour. To
test it, take a brushful,
and note whether the
fluid runs off it like
water, or almost as
thickly as treacle ; if the
former, continue the boiling ; if the latter, add some
perfectly boiling water. Continue the boiling for a
minute or so and try the consistency again. When it is
just right the glue should fall easily from the brush and
not be so thick as to break up into drops.

If you are in a great hurry, you will probably be
tempted to put the gallipot in an oven or to boil up the
glue in an old saucepan in direct contact with the flame
of the stove, but if you do so you run a grave risk of over-
heating the glue and ruining its strength. The object
of using the proper gluepot or of immersing the gallipot

Fiji. 1.— Double-
saucepan Glue-
pot

Fig. 2.— Section
through Glue-
pot

Fig. 3. — Glue-brush made by hammering end of piece of Cane

in water is to ensure that the glue is not heated to a
temperature exceeding that of boiling water.

io6

Glue: How to Prepare and Use It

The glue as prepared will be ready for immediate
use, or, if preferred, can be allowed to cool into a jelly,
and can then be quickly melted at any time as required.
But after a few re-meltings its strength becomes impover-
ished, and it is wise to make up some fresh. If put aside in
a damp place it will become mouldy, and then on no
account should it be used.

Making: a Glued Joint. — Now we come to the right
way of using the glue. The two surfaces that are to be
joined should be of a good fit one with the other. They
must be clean, as even a touch of grease prevents the
glue from taking a firm hold. They must be warm, as
glue applied to a cold surface is suddenly chilled and half
spoilt. I generally contrive to do a small gluing job in
front of the fire. I have the glue boiling hot, I have
previously taken care to leave the work somewhere near
the fire so as to be gently but thoroughly warmed, and
then, just before applying the glue, I hold the surfaces
about a foot away from the fire, and when the work be-
comes really warm I apply a thin layer of glue to both
pieces, and at once bring them into contact one with the
other.

The next point is of great importance. As I have
already said, the glue is required in a thin film only, and
we can only ensure this by squeezing out the surplus.
With two flat surfaces this is easily done by sliding one
on the other a few times, and then when the glue starts
to grip the two together bringing the two pieces into
their proper position ; if possible, put the work away
under pressure for a whole day at least for the glue to get
hard. In hundreds of cases the work is of such a shape

107

Every Boy His Own Mechanic

that sliding one piece on the other is quite out of the
question, and in all such cases we have to exercise more
care in applying the glue. Whilst every spot must be
covered, only a thin coat is required, and the two pieces
must be brought together under pressure. Everybody
will have his own way of producing that pressure, one of
the easiest being to place the work between two flat boards
and put a heavy weight over the top. A pile of books is
an excellent weight if nothing better is available. A good

Fig. 4. — Wedge-cramp on Bench-top, etc., for Frame or other article

clamp is made with rope on the principle of the picture-
frame cramp illustrated on p. 91. Fig. 5, on opposite page,
shows how it may be arranged, and is as self-explanatory
as the wedge-cramp illustrated by Fig. 4, in which figure
the pair of folding wedges should be noted.

There are some woods that are very porous, and they
tend to soak up the glue and prevent a satisfactory joint
being made. In such cases put a brushful or two of
glue into a pot, pour on a little boiling water, mix up
thoroughly, and brush this glue size over the surfaces
that are to be glued. Allow twelve hours to dry, and
then proceed in the ordinary way already described.

io8

Glue: How to Prepare and Use It

Special Glues. — With two more hints the subject of
gluing may be dismissed. For small jobs I never go to the
trouble of preparing glue. It is so much more simple
and easy to use seccotine, which can be squeezed from its
collapsible tube in just the exact quantity required, but
simply because this is a cold glue do not neglect to have
your work thoroughly warmed, this making a great
difference to the strength of the joint.

For some jobs ordinary glue would not long be satis-
factory. It does not
matter how old glue
may be, it is always
influenced by moisture.
That is why glue is
quite useless in any
outdoor woodwork. The
joints simply fall apart.
Sometimes, though, it is
very convenient to use
glue for small fancy
work which may occa-
sionally run the risk of being wetted, or which may
have to stand the effects of a moist atmosphere. For-
tunately there is a most useful chemical, bichromate of
potash, obtainable from an oilshop or chemist in the form
of orange-red crystals, which can be added to our glue to
make it waterproof. The curious thing is that this glue
to which the bichromate has been added becomes water-
proof only when exposed to the action of light, and
therefore after it is prepared it must be kept in a dark
place (it comes to the same thing if it is kept in a stone-

log

Fig. 5. — Rope-cramp

Every Boy His Own Mechanic

ware or black glass bottle, corked or stoppered) until it
is wanted. The proportion of bichromate to be added to
the glue is not of very great importance. First of all
prepare the glue in the ordinary way, and while it is hot
add, say, | oz. of the chemical for every 3 oz. or 4 oz.
or so of cake glue originally used. The chemical is
poisonous, and should not be touched by the hands, as
it affects the skin.

I think that seccotine is the best liquid glue that I
have tried, but as I am fully aware that my readers are
the sort that want to make everything for themselves, I
give here a recipe for a reliable cold liquid glue. Break
2 oz. of Scotch glue into fragments, and place in a bottle
containing 8 oz. of ordinary commercial acetic acid, and
1 oz. of water. In due course the glue will swell up, and
the bottle can then be stood in a saucepan of warm water,
and very gently heated until the glue is actually melted.
Add 1| parts more of acetic acid, continue the gentle
warming for a few minutes and allow to cool.

ELECTRIC BATTERIES AND HOW TO
MAKE THEM

On another page I explain the difference between a
primary battery and a secondary battery (accumulator),
and I now propose to show you how to make two or
three kinds of batteries, one suitable for ringing bells and
very occasional flashing of a miniature lamp, another
adapted for electro-plating, and a third, of the " dry "
portable kind. A " battery " is really two or more
" cells," but the first term is commonly used for a single
cell as well.

Leclanche Cells. — There are some batteries which
do not pay to make. The ordinary bell-ringing Leclanche
(Fig. 1), for example, is rarely made at home, because all
its parts are so cheaply bought. It consists of a jar
(Fig. 2), a zinc rod (Fig. 3), connected to which is an in-
sulated wire, and a charged porous pot (Fig. 4). These
parts are assembled as in Fig. 1, and the space between
porous pot and jar is filled up to the lower level of the
black part with a solution of sal-ammoniac powder in
plain water. 1-pint, 2 -pint, or 3-pint cells are usually
made, and will require respectively 3 oz., 5 oz., and 10 oz.
of sal-ammoniac. An ounce more or less does not matter
much. The two elements — there are always two distinct
metals in a cell, carbon, in this sense, being a metal — are

III

Every Boy His Own Mechanic

zinc and carbon. The zinc rod you can see in the illus-
trations. The carbon is in the porous earthenware pot
into which it is packed with a mixture of granulated
peroxide of manganese and carbon, there being holes at
the top for the escape of the gas evolved in use. The tops
of the jar, zinc rod and porous pot are coated with bitumen,
pitch, or brunswick black, as shown, and often, too, they
are further treated with hot paraffin wax, the object being
to prevent the crystals in the solution gradually creeping
up and corroding the connections.

Old zincs from Leclanche cells need treatment to make
them as good as new. The particular treatment is amalga-
mation with mercury, the purpose of which is to stop
internal local action when the cell is supposed to be at
rest. The impurities in the zinc set up between them-
selves electrical action — that is, scores or hundreds of
microscopic cells or batteries are formed — which in course
of time runs down the cell. So, whenever a cell contains
zinc rods or plates — and many cells do — it is wise to keep
them well amalgamated, the method of doing which is to
dip the zincs in dilute sulphuric acid to make them clean
and bright, swill with water, put them in a dish, and then
rub mercury over them with some tow fastened on a stick.
Mercury instantly alloys or amalgamates with the clean
zinc. Don't touch the mercury with the fingers and avoid
inhaling its vapour.

The making of the porous pot is out of the question,
but there is a good type of Leclanche cell that has a
sack instead of a pot, and you can make this up for your-
self if you like. Its size will depend on that of the jar
you propose to use. A 3-lb. jam-jar before me as I write

112

Electric Batteries

would take a sack 5 in. high, and not much more than 2 in.
or 2| in. in diameter. Adopting the second dimension,
you will need a piece of thin, loosely-woven canvas, not
cloth, about 8 J in. square, and a disc of the same material
to form the bottom of the sack. Make the square piece
into a cylinder (Fig. 5) and see that the seam is strongly

Fig. 4. — Carbon and
Porous Pot

Fig. 3. — Zinc Rod

Fig. 2.— Jar of Cell

1^3

Every Boy His Own Mechanic

stitched. The carbon rod or plate must be bought, and
if it has a terminal screw attached to it all the better ;
if not, get some old lead and fine sand. Make a mould for
a head to the carbon and place a terminal and the carbon
rod in such a position that when the lead is melted (in
an old iron shovel over a glowing fire) and poured in, it
will form a head and connect the screw
to the carbon. Or a reader who under-
stands electro-plating could deposit elec-
trically a good thick coat of copper on
the carbon and solder the terminal to it
with tinmen's solder. In either case, on
completion, coat the top of the carbon
and everything up to the bottom of the
terminal with brunswick black or paraffin
wax.

For packing the carbon in the sack,
you will need some granulated carbon
and manganese peroxide as fine as rice,
but not containing dust. You can get
them from dealers in electrical sundries.
Mix together equal parts of each, and
pack lightly into the sack after inserting the carbon.
Tuck in the canvas and tie neatly at the top after
packing in as much as the sack will take, but see that
the terminal is left projecting (Fig. 5). Coat the tied
end of the sack with brunswick black.

The best form of zinc element for this cell is an amal-
gamated plate bent to cylindrical shape. For a jam-jar
measuring inside nearly 4 in. in diameter by about 6 in.
high, the plate could be 5 in. or 6 in. high and 9 in. long

114

Fig. 5. — Carbon

and Charged Sack

of Sack

Leclanche Cell

Electric Batteries

(see pattern. Fig. 6), bent to form an incomplete cylinder
3 in. in diameter. A copper wire should be soldered to
the connecting lug, and the zinc will need to be amalga-
mated as already described. The lug is bent over to form
a hook so that the zinc hangs on the glass jar and does not
touch the bottom. Actual dimensions are of small im-
portance, and will depend upon those of the jar used.
Made to the dimensions here suggested, there will be a
clearance of I in. between sack and circular zinc, and as it
is really important that this be maintained, I suggest
you put one or two thick
rubber rings around the sack
to prevent contact. All being
ready, charge the battery with
a solution of about 6 oz. or
7 oz. of sal-ammoniac in rain
water or distilled water, leave Fig. 6.— Pattern for Cylindrical
for a few hours, and the cell ^'"'^ °^ ^^""^ Lcclanche Cell
is ready for use. It will, if well made, yield a current
at 1'6 volt, and two such cells side by side, with
the zinc of one connected straight to the carbon of the
other, will give a current at 3*2 volts and would easily ring
a bell or two, or occasionally glow a miniature lamp of
approximately the same voltage ; if more than one lamp
is used connect them up on the parallel system, by bridge
wires between two main conductors (see p. 47).

A Plater's Battery. — We will next consider an al-
together different type of battery or cell from the above.
For electrical experiments and for plating with gold,
silver, copper, etc., you require a battery that will give a
current for quite a time without running down. The

lis

Every Boy His Own Mechanic

Leclanche battery, either wet or dry, is useless for such
work, and instead a Bunsen, Daniell or a WoUaston
battery should be used. I could tell you how to make
either the first or second, but there would not be much
purpose in doing so, as you would have to buy all the
parts, and there would be very little " making " in the job
of putting the battery together. I show you in Fig. 7
what a Bunsen cell looks like. First of all, there is a glass
or stoneware jar d, in which is a zinc cylinder c, to which
one of the terminal screws is attached. The zinc forms
one pole of the battery. Inside the zinc cylinder is a
porous pot B, and inside this again is a square or rect-
angular rod of carbon which forms the other pole and
carries a terminal screw as shown. The zinc cylinder is
kept well amalgamated by the method I have already
described, and the battery is charged by pouring nitric
acid into the porous pot until about three-quarters full,
while the space between that pot and the outer stoneware
or glass jar needs to be filled with a mixture made by
pouring one volume of sulphuric acid into nine parts of
svater. Note the caution : do not pour the water into
the acid, or you may be hurt by the spurting acid.

What is known as a French Bunsen cell has a sulphuric
acid mixture in the porous pot as well as in the outer
vessel, and is to be preferred to the other type because
it is free from the noxious fumes generally associated with
the use of nitric acid. For all sorts of small plating jobs,
especially when the conducting wires are fine, and therefore
offer a high resistance, either of these forms of the Bunsen
cell is first-rate, but as I have said, you can scarcely
" make " it ; you buy it all ready for use.

ii6

Electric Batteries

Still better for small gold- and silver-plating jobs is the
Daniell battery, which provides a greater volume of current
at a lower pressure. This, again, is a battery which you
buy ready made. It is simply a round glass jar containing
a cylindrical copper plate, inside which is a porous pot

Fig. 8.— Bottle Bichromate Cell

Fig. 7. — Elevation of a
usual form of Bunsen Cell

containing a zinc rod. In

the porous pot is a mixture

of sulphuric acid and water

(certain other solutions could

be used), and outside the porous pot is a saturated solution

of copper sulphate.

The bottle bichromate cell or Grenet's flask (Fig. 8)
has a zinc plate, which can be lifted clear of the solution,
between two carbon plates. The solution consists of
1 pint of hot distilled water or rain water and 3 oz. of
bichromate of potash, to which is added, drop by drop,
3 oz. of strong sulphuric acid. The solution must become

117

Every Boy His Own Mechanic

cold before use. This is a powerful cell, but is best bought
ready made.

The best type of plating battery to be made by the
boy himself at home is a copper-zinc couple of the Wollaston

type. It is an inter-
esting job to make a
cell or battery of this
kind, and quite an easy
one, too. The idea is
to support in an acid
solution a piece of zinc
with a piece of copper
on each side of it.
First look out some
jars that will serve
your purpose — jam-
jars of stoneware or
glass or specially
bought porcelain jars.
Two bridge-pieces of
wood cut to shape,
shown in Fig. 9, will be
wanted to go across the
top of each jar. Two
cells will give enough
pressure for ordinary small jobs, so four bridge-pieces will be
required. Get from a plumber or from an electrical dealer
two pieces of rolled zinc (cast zinc is impure and liable to
break into holes when used). The recess shown in the
bridge-piece (Fig. 9) is the exact width of the zinc plate,
while its depth should be not quite half the thickness of

ii8

Fig. 10.-

-Zinc Element clamped between
two Bridge-pieces

Electric Batteries

the plate, so that when the latter is put in the recess and
the other bridge-piece put in place, as in Fig. 10, two
screws can pass through the wood clear of the plate and
clamp it in position. But before this is done both wood
and zinc must be treated, the former to cause it to resist
the action of any acid
that may reach it and
to stop the creeping up
of any chemicals, and
the latter to preserve
it from local action.
The wood should be
soaked in paraffin wax
or in candle wax, and
the plate should be
thoroughly amalga-
mated with mercury,
as already explained.

For each cell there
must now be obtained
two copper plates. It
does not matter how
thick they are, but
the area of each one
ought to be greater than that of the zinc which will
come between them. The inner surfaces (those that
will come opposite the zinc) should be scored over
with a file or other tool, and small holes to receive
screws should be bored at their top ends so that they
may next be attached to the wood exactly as shown in
Fig. 11, using brass or copper screws sufficiently short to

119

Fig. 11. — Copper Elements and Zinc

attached to Bridge-pieces of

Wollaston Cell

Every Boy His Own Mechanic

avoid touching the zinc plate. If you like you can get special
clamps which will connect together the copper plates and
grip them to the bridge and obviate the use of screws.
Two terminals, as shown, are essential. If the arrange-
ment is now placed in the vessel, and a mixture of one
part of sulphuric acid and ten parts of water poured in,
the cell will immediately give current, and if you arrange
some means of propping the plates up so that only part
of them is immersed in the acid you can regulate the
current yield and adapt it to your requirements. You
could do this simply by having two or three pairs of
different sized blocks of wood well soaked in paraffin wax
to place on the edge of the jar to support the bridge-piece.
As already explained, you get a higher pressure if you
connect the cells in series — that is, the coppers of one to
the zinc of the other, and the remaining plates to the work.
But for plating purposes great pressure is seldom neces-
sary, and a good volume of current is more desirable, to
obtain which you connect the cells in parallel, that is,
any two like poles together, the other plates joining up
to the circuit or work as before.

I show this particular type of battery because it is
extremely easy to make, and the materials are readily
obtained ; but I do not profess that it is an ideal device.
It needs to be carefully managed, and, in particular, the
plates should not be left immersed in the acid when not
in use. It is worth while, on removing them from the
acid, to rinse them thoroughly under the tap and lay them
aside until required. Then, too, the zincs must be kept
well amalgamated, which is a simple enough job, but
involves the use of mercury. In the instructions I give

1 20

Electric Batteries

on page 112 for amalgamating zincs, I explain that the
metal must be cleaned with dilute acid, but where this
is inconvenient hot strong soda water can be used in-
stead, although the acid is preferable. When the dilute
acid in the cell appears to have a blackening effect upon
the plates and there is a hissing noise, local action is exces-
sive, and it is a sign that re-amalgamation is necessary.

Flash-lamp Batteries.

terest is taken in the
tiny batteries used
in torches and flash-
lamps. How often
am I asked whether
they can be re-
charged ! They can-
not. Neither do I
think they can be use-
fully made at home
by the boy mechanic,
inasmuch as the

I know what a great in-

Fig. 12. — Section through

a Three - cell 4^ - volt

Flash-lamp Battery

Fig. 13. — Sec-
tion through one
of the cells of
the Flash-lamp
Battery

work would scarcely pay unless attempted in quan-
tity. A flash-lamp battery is actually a moist Le-
clanche ; when of the flat type it consists of three little
cells, each 1| volts, connected in series, the total pressure
being, therefore, 4| volts. A section through the battery
is given by Fig. 12, in which a is one of the cells, b is a
piece of waxed card, which insulates one cell from the
other, c is the wire connecting the carbon of one cell to
the zinc case of the next, and d is the terminal (a piece
of flat brass) from the zinc element, the other terminal —
from the carbon — also projecting through the top, but

121

Every Boy His Own Mechanic

being unlettered in the diagram. Between the three
little cells and the outside container is fine sawdust or
cotton wool E, while f is a sealing of pitch, and G is a
paper wrapping.

Taking one of the three little cells separately, it con-
sists of a cylinder of very thin zinc a (Fig. 13) lined with
blotting-paper b, at the bottom of which is a disc of card c.
Standing on the disc is a carbon rod d over the top end
of which has been forced a brass cap e to allow of a wire
being soldered on. Active chemical material is packed
in between the carbon rod and the blotting-paper lining,
as at F. The blotting-paper is turned in at the top {see
h), and each cell is finished off with a seal j of pitch or
of pitch mixed with resin.

In course of making, the blotting-paper lining to the
zinc cylinder has been saturated with a solution made by
mixing 2f oz. of sal-ammoniac, f oz. of zinc chloride,
I oz. of glycerine, and 7 oz. of water that has been boiled.
The chemical f surrounding the little carbon rod consists
of some such mixture as 9 parts of finely-powdered carbon
and 4 parts of manganese dioxide. These powders must
be thoroughly well mixed, and then dampened with a
similar solution to that already used, but note that it
contains less sal-ammoniac, the proportions being 1 oz.
of the last-named, 1 oz. of zinc chloride, I oz. of glycerine,
and 7 oz. of water. It is found that the proportion of
this solution used in relation to the powder exercises a
great influence on the success or failure of the battery.
Not enough should be used to make the powder into a
paste. The condition has been well described as a " moist
powder, crumblingly damp."

122

Electric Batteries

There has been a tremendous amount of experimenting
in the manufacture of these flash-lamp batteries, and all
sorts of different mixtures have been tried. One of the
best of them is said to be a mixture of 2 parts of carbon,
2 of plumbago or pure graphite (pure blacklead), and 3
parts of manganese dioxide, all in fine powder, the
dampening mixture consisting of 1| oz. of sal-ammoniac,
2 oz. of zinc chloride, 1| oz. of glycerine, and 7 oz. of
water.

Honestly, I do not think you will get as good results
with home-made flash-lamp batteries as with those you
buy ready made ; but I know also that many of you will
try to make them, so I feel compelled to add a few prac-
tical notes on the method of making up the cells. For
making the zinc cylinders, get the lightest, thinnest zinc
you can, and cut it into pieces measuring 2f in. by 2^ in.
Wrap them round a round piece of wood to form cylinders,
and thoroughly well solder the seam, afterwards cutting
discs to make bottoms for the cylinders, and soldering
these in place from the outside. Or, to avoid the soldering
in of the discs, you can place the open-ended cylinders on
a tray and pour in a |-in. layer of marine glue or pitch.
Cut pieces of blotting-paper measuring 7 1 in. long by 2 j^n.
wide, and roll round a ruler to form a cylinder which will
tightly fit the zinc cylinder already made, allowing a
little of the blotting-paper to turn in and form a support
for a cardboard disc, which should be pushed into the
blotting-paper cylinder to form a bottom. Pour in the
first of the exciting mixtures given above, allow to remain
for fifteen minutes, pour out, and then place on end to
drain for about an hour and an half. The carbon pencils

123

Every Boy His Own Mechanic

must be tightly pushed into little brass caps. The tops
with their caps should be stood in molten paraffin wax
or candle wax for the purpose already explained. Place
the carbon rod in the centre of the little cell, and having
the black mixture moistened to the proper consistency,
ram it tightly round the carbon by means of a piece of
tubing. The mixture should stop short half an inch
from the top of the carbon, and the blotting-paper be
folded in over it. It is most important to avoid any
little bridge of black mixture extending directly from the
zinc cylinder to the carbon rod, as such a bridge would
short-circuit the cell and very rapidly exhaust it. Leave
the mixture time to get a trifle drier, and then seal with
some pitch, afterwards melting a hole through the pitch
with a hot wire to allow of the escape of the gases which
are evolved later. The cells are connected together with
No. 24 gauge wire, and the terminals are of thin spring
brass, all soldered on. Three cells are laid side by side,
connected up as described, partition slips of waxed paper
put between them to prevent the zincs touching each
other, and the whole wrapped round with brown paper,
the top being packed with wadding or sawdust to prevent
movement, and this being sealed over with pitch, which
makes all secure. For the sake of appearance the cells
are finally wrapped round with black paper.

124

SOLDERING

Most people associate mechanics with soldering, and
suppose that a boy who is handy with tools must, of ne-
cessity, know how to use a " soldering iron." Soldering
looks so easy. All you do is to put a hot iron on the
kettle spout, touch it with a stick of solder, and the leak
is mended. That's what they think.

Well, we don't use a " soldering iron " at all, and in
the writer's humble opinion, soldering is not easy. Of
course, when you have learned the right temperature for
the soldering bit, how to clean the work, and how to make
that annoying bead of solder flow where you want it to,
the process has become easy enough. But I rather think
you will find your first soldering job to be something
short of perfection. On the other hand, you may have
beginner's luck !

Solder. — Soldering consists in uniting two pieces of
metal by means of an alloy melted by heat. An alloy is
a mixture of two or more metals, and it is found that the
best and cheapest solder for most of the metals in ordinary
use — brass, copper, zinc and iron — is a mixture of tin and
lead. As most boys will be interested in soldering such
everyday metals as tin plate (which is steel coated with
tin), brass, and copper, we may say that for all these an
alloy made by melting 2 parts of tin with 1 of lead makes

125

Every Boy His Own Mechanic

an excellent solder. In asking at the shop for such a
solder as this, say that you want " tinman's fine solder."
However, if you will be guided by me, you will not, at
8rst, purchase your solder in the ordinary form of sticks
such as you have seen used by the tinker and candle-
stick maker. There is a special preparation of finely-
powdered solder, known as " Tinol," and nothing easier
for the use of the boy mechanic has ever been introduced.
On opening the flat tin in which the substance is put up,
you find it to consist of a wet paste, and a little of this
can be taken up on the point of a penknife or wooden
stick and placed exactly where it is required. It has one
great advantage ; all soldering requires the use of a
" flux," which keeps the metal chemically clean when it
becomes heated. When ordinary stick solder is used the
flux has to be separately applied. In " Tinol." how-
ever, the flux is already mixed with the solder, and a very
excellent flux it is.

Should you particularly wish to use stick solder, you
will need to prepare a separate flux by placing some pure
hydrochloric acid (known also as muriatic acid) in a jam-
pot, and adding some nice clean cuttings of new sheet
zinc — just a few at first and then more until you notice
that, although there is some zinc left at the bottom of
the jar the acid has ceased to bubble up. It is important
to see that what appears to be superfluous zinc is left in
the liquid. Leave it overnight, and then pour off the
liquid into a glass jar having a good wide mouth. This
liquid is now a solution of chloride of zinc, and workmen
know it as " killed spirit." For applying this flux to
the metal you can make quite an excellent brush by

126

Soldering

Fig. 1. — Pointed Soldering Bit

taking a short piece of cane and hammering one end of
it until the fibres become like bristles. For fine work the
flux can be applied with a piece of galvanised wire or
with a knitting needle.

As with solders, so with fluxes. I recommend you to
use a flux already made, and one of the best obtainable
is " Fluxite," a paste flux put up in flat tins ; but, as
already stated, if you decide for the easiest possible pro-
cess, you will employ " Tinol," and leave stick solder and
separate fluxes to

a later date. That — ^ ^™_^-: -~>n

is all you need to
know about the
materials. Now
for the tools.

The Bit.—
People talk
glibly of a solder-
ing " iron," when
they ought to
speak of a sol-
dering "copper." Workmen know it as the soldering
"bit." Figs. 1 to 3 show the three forms in which it
is generally obtainable, and the one I prefer whenever
it can be used is the hatchet-shape shown last. By the
way, the "Tinol" firm sells a telescopic bit of the
hatchet shape which will answer most small requirements.
The bit is simply an iron rod with a shaped piece of
copper at one end and a handle, generally of wood,
at the other {see Fig. 4). The "Fluxite" firm also have
a good collapsible bit {see Fig. 4a).

127

Bit for Internal Soldering, etc.

Fig. 3. — Hatchet Soldering Bit

Every Boy His Own Mechanic

A bit must be heated to a temperature slightly higher
than that at which the solder will melt, and the young
mechanic sometimes has difficulty in finding just the right
source of heat. The kitchen fire fouls the bit ; the heat
of the gas-ring is not concentrated enough and the bit
takes too long to get hot. The flame of a spirit lamp can
be used for heating the bit, but this again is a trifle slow.
If you have what is known as a bunsen burner (Fig. 5)
you might make that serve. An incandescent gas burner
is really a bunsen burner, and if you possess one of the

Fig. 4. — Telescopic Bit

SCR£VVE.D JOINTS'
Fig. 4a.— Collapsible Bit

old-fashioned upright kind, you could take off the mantle
together with its prop, turn the gas on full, light up, and
then have a fair-sized smokeless flame in which, if you are
ingenious, you can support the copper bit while it is
heating, but we fear that at the best it will be a very in-
convenient method. The tool shops sell special stoves
for heating bits, some of them burning gas, and others of
them charcoal, but not many amateur solderers would
dream of buying one. Fortunately many readers will
have already in their house a quite excellent stove for the
purpose, and until thev read of the fact in this place will

128

Soldering

be unaware of it. Hundreds of thousands of gas-heated
laundry irons are now in use, and if the ladies of your
establishment possess one, do your best to borrow it
when you mean business in the soldering line. In the
writer's experience, one of these irons has proved a
most excellent heating device. Connect up the iron by
means of a flexible tube to the gas-bracket, turn the gas
about half on, light up, lift up the handle of the iron,
and insert the bit so that the flame plays right on to the

\rt

Fig. 5. — Bunsen Burner

copper.

There is still another method
possible if you have a gas-heating
stove (not a gas-cooker) in your
house. Lift out some of the asbes-
tos clay, and rig up the copper bit
on a couple of bricks or on anything
else handy and fireproof, so that
the bit is held right in the top part
of the flame. A small bit can be
well heated in the blue flame of a
"Primus" oil stove. I have dwelt somewhat at length
upon the means of heating the bit, because I have
found that it is the first big difficulty that the amateur
solderer comes up against.

If you simply took two pieces of tin plate just in the
state you might happen to find them in, and then with
solder and the copper bit just as it comes from the shop
tried to solder them together, you would meet with more
or less complete failure. Although you might not know it,
judging from appearance only, the work and the bit are
dirty, and the solder when melted will not flow over or

J 129

Every Boy His Own Mechanic

" wet " or " tin," as it is termed, any unclean surface.
So don't forget that when a job has to be soldered, the
very first thing to do is to scrape it clean, using for the
purpose an old knife or a file.

The bit, which is expected to convey the solder to
the actual spot where it is required, must for the same
reason also be scrupulously clean, and before starting
work it is customary to tin it, that is, actually to coat it
with the solder. Plenty of people fail in such a simple

job as this just
because they
will not take the
necessary trouble
to get the metal
nice and bright.
With a file go
over it until the
whole of its sur-
faces resemble
new metal. Then heat it to what is known as a dull red,
quickly rub it over again with a file, and apply some
" Tinol " to it, rubbing the bit on a piece of clean tinplate,
so that the solder flows all over it. If using stick solder,
dip the bit, after heating and cleaning, in the flux, and
then rub the solder on it ; or, better still, get a small
block of sal-ammoniac from the oilshop, and, after
heating the bit, rub it on the block (Fig. 6), touch the
bit with the solder, and you will see it immediately
flow over the surface of the metal. You will not care
for the smell of the fumes that will arise from the sal-

Vl'i'i'i'i'lT''

lllllll'i'lllli'ih

Fig. 6. — Tinning a Soldering Bit in
block of Sal-ammoniac

ammoniac.

130

Soldering

Patching a Vessel. — Now we have tinned our bit
and are ready to do some useful work. It is more than
likely that the lady of the house has a tin-plate saucepan,
kettle or dish that is in need of repair, and will be only
too delighted to allow you to try your " 'prentice " hand
upon it. As a typical soldering job, let me assume that
you are going to cover a hole in a tin-plate vessel {see A,
Fig. 7) with a neat little patch which we can readily cut
with some
stout scissors
from a new
coffee tin or
anything else
of the sort.
Scrape around
the hole in the
vessel and
make it nice
and bright
{see b). Then
place the little piece of tin plate so as fairly to cover the
hole (c), and with the point of a nail scratch the outline
of the patch upon the work {see d) ; remove the patch,
and by means of a bit of wood or the point of a
bradawl apply some " Tinol " thinly all over the place
and slightly beyond where the patch is to go. Then
replace the patch as at c.

In the meantime the soldering bit has been getting
nicely hot in some one of the ways I have already de-
scribed. Let it rest well on the patch with the object of
transmitting as much heat as possible, and move the bit

131

Fig. 7. — Stages In preparing a Soldered
or Sweated-on Patch

Every Boy His Own Mechanic

about so that every part of the patch comes under the
influence of the heat.

The job is done. The patch has been "sweated" on
and with reasonable care the result is a good one. But
probably you will not be satisfied. You will want to
see the solder in a nice ring all round the patch. There
is no reason why you should not, and the extra solder will
be extra security. See that the bit is nicely hot, but not
so hot that the tin upon it has been badly discoloured
and burnt. If it has been, give it a touch with the file,
rub it on the sal-ammoniac, and apply a little solder to
its face, thus re-tinning it. Then transfer the bit to the

Fig. 8. — Mouth Blowpipe

edge of the patch, and apply a ring of " Tinol," and with
the soldering bit in perfect condition gently wipe it round
the edge of the patch. If you are using stick solder, you
will need first to ring the patch with " killed spirit," and
then apply bit and solder together. When you are a
little more experienced you can experiment with the
object of lifting up a bead of molten solder on the point
or edge of the bit and transferring it to the work exactly
where it is wanted. It is all-important when using stick
solder to hold the work in such a way that the solder can
run downhill to the spot where it is wanted. Many a
boy has tried to make the solder climb the handle
of a kettle, whereas if he had remembered that water
always runs downhill he would have saved himself some

132

Soldering

Fig. 9. — The three Cones or
Zones of a Blowpipe Flame

annoyance and
have had the
pleasure of pro-
ducing a result
of which he
could have been
proud.

Soldering: with the Blowpipe. — Not all soldering
is done with a soldering bit. Some of the neatest and
cleverest work is executed by means of the mouth blow-
pipe which is simply a bent tube of glass or metal shaped
as in Fig. 8. This blowpipe is used for directing a tiny
jet of flame upon a speck of solder resting on the spot
that has to be soldered. The flame of a candle or spirit-
lamp when directed and assisted by the mouth blowpipe
becomes hot enough to melt solder most readily, as a single
experiment would prove. In using the blowpipe {see
Fig, 10) a good breath is taken in, so filling the lungs with
air. The blowpipe is applied to the base of the flame,
and a gentle but constant current of air blown through
it. It will be seen
that the candle ^^^''^'^'^'/^'"
flame has three
parts or zones
{seeFig.9). That
at the base
marked x is the
coolest of them
all, and in a dark
room would be
almost invisible.

-Using Mouth Blowpipe with
Spirit-lamp Flame

'33

Every Boy His Own Mechanic

The next zone marked y gives forth more light than
either of the others. The tip of the flame marked
z is the hottest of the three, and it is this part of
the flame that does the work. You must try in using the
mouth blowpipe to breathe through the nose, and at the
same time keep the cheeks full of air, and a steady current
passing through the blowpipe. A good flame will be of
a bluish colour with a yellowish or brownish tip. Blow-
pipe soldering comes in so useful when the job is too
small for the soldering bit. Say, for example, you wish
to attach the head of a pin to a coin. Clean the spot on
the coin where the junction will come, and also the head
of the pin. Touch both of them
W^"''" ^ with the "Tinol." and, supporting

I them on a piece of charcoal or brick,

direct the flame on to them with a
blowpipe one at a time. This "tins "
them, that is, it coats them with
solder. Leaving the coin where it is,
Fig. U.—An easily-made hold the pin on the end of a strip of
wood, and place its head in position
on the coin exactly as it is to be when soldered. Then
a touch with the blowpipe flame will unite the two.

Fig. 11 shows how easily a spirit lamp for blowpipe
soldering can be made. The wick tube is any small piece
of tube available, and it slides fairly tightly through a
hole cut in the lever lid of a small "self-opening" tin
box. The wick is of loose threads. Note the small
holes at the top of the wick tube ; they considerably im-
prove the action of the lamp. Methylated spirit is the
fuel. Lamps on this principle can be bought ready made.

134

Soldering

Silver Soldering. — So far, I have talked about soft
soldering only, that is, about solders that melt at the
comparatively low temperature of a black-hot iron, but
there is such a thing as hard soldering. The joints in a
really good piece of silver-work or in a well-made model
engine or boiler are hard-soldered, for which purpose an
alloy of tin and lead would be of no use whatever, and
recourse must be had to an alloy of silver and brass. Take
my advice and if you use silver solder at all buy it ready
made. Such a little bit will go such a long way. Buy it
in the form of very thin
sheet and with a pair of very
strong scissors, or, if you have
them, with a pair of snips, cut
the sheet up into tiny squares Fi^- 12.— Gutting up Silver

.^ -^ . ^ Solder into Paillons

about ^ in. ( see Fig. 12 ).

These are known as "paillons," which you may care to
know is a French term. The flux for silver soldering is
quite different from that you have already used. It is
made by taking a piece of lump borax, moistening it with
water, and rubbing it on a piece of slate until a thin paste
is formed. Fig. 13 (p. 136) shows the outfit.

If you ever try to build a model boiler or engine, you
may need to make a joint in a tube or to solder the end
into a tube (see Fig. 14). The surfaces having been scraped
perfectly clean should have some of the borax paste ap-
plied to them with a brush, and then, with the same brush,
the tiny paillons of silver solder are placed in position all
along the joint. Now slowly heat the work in the blow-
pipe flame, but do not at first let the flame fall upon the
solder. The latter should not be melted until the metal

I3S

Every Boy His Own Mechanic

all round it reaches the temperature at which the solder
becomes liquid. This course will serve to dry the borax,
and the bubbling up may move some of the solder which
will need to be pushed back into place. As the bubbling
of the borax ceases, slightly advance the flame, and in
due course the solder will melt and run into the joint,
providing the work is held at such an angle that it is
natural for the solder to run that way. Do not imme-
diately remove the flame, but let it remain for a few

Charcoal Block
setioPlasrer

Wafer Bowl

BiOWpipi

Scraper
Fig. 13. — Outfit for Silver Soldering

seconds so as to cause the solder to sink right into the
joint.

Let the job get cold slowly, and then clean off the
borax by placing it in a pickle made by pouring a tiny
glass measureful of sulphuric acid into twenty times the
quantity of water. By the way, never pour water into
sulphuric acid, or the acid will spurt, and if it falls upon
your hands or face you won't forget it in a hurry, and
should it fall upon your clothes you can depend upon
it that it won't do them any good ; probably some of
your experiences in the chemistry lab. will be fresh in
your memory, and my warning may be unnecessary,

136

Soldering

I have described only one of the methods of hard or
silver soldering because the process is well-nigh essential
in serious model building, but I think I ought to warn
you that it has difficulties all its own, and that to become
an expert silver-solderer demands a lot of practice, and

FJam cii'sc

Solder
/nside.

( 'Binding ffire
f/on^rd Disc

Inside Method

Fig. 14.

SecOoto
of finished

f^^^M/

Tube

Outside Method

Silver Soldering ends into Tubes, especially applicable to
Model Boiler Building

there is a great deal more to be said about it than I have
ventured to bother you with in this chapter. I prefer
to occupy my space with information on work that
is within nearly every boy's capacity, as measured in
equipment and skill.

137

MAKING SIMPLE WOODEN TOYS

I WANT to show you in this chapter how to make three
wooden toys (all of them designed by Mr. I. Atkinson,
to whom I am much indebted), which should be well
within your capabilities. There is not a really difficult
bit of work in any one of them.

A Toy Gymnast. — One of the happiest toys I have
seen for a long time is the toy gymnast, a photograph of
which is given in one of the plates accompanying this
book. Turn to that plate for a moment, and I will show
you how the gymnast works. The figure or puppet is of
thin, flat wood, normally hanging with his hands above
his head, and the string which supports him is arranged
as shown in the plan and elevation. Figs. 1 and 2 here-
with. Normally the string is crossed, but when the lower
ends of the levers are squeezed together by the fingers the
upper ends are forced apart, the string is pulled taut, and
the figure is jerked upwards in a most realistic manner.
There is no end to the contortions and amusing positions
of which the gymnast is capable, and when the maker of
the toy here described sent it to me I very soon discovered
that both juniors and seniors took a huge interest in its
antics. The toy, which seems to be still a novelty, al-
though a very old one, consists of a base, a post, a cross-
piece, two upright levers, the string, and the figure.

138

Making Simple Wooden Toys

u±

W?3

y — T"

Fig. 1.- — Plan showing

how Toy Gymnast is

suspended

Figs. 3 and 4 are front and side elevations of the wood-
work, the levers being shown broken to economise space.
We Avill deal with the parts separately, and make all
clear as we go.

In the first case, a fairly hard
wood should be used. The levers need
to be of tough stuff, or some careless
body will sooner or later break them.
For the base a, post and cross-piece,
you had better use mahogany, oak,
walnut, or other hard well-seasoned
furniture wood. The base should not
be less than f in. thick, and 4| in. or
5 in. long by 3J in. or 4 in. wide. A
hole is bored in its exact centre to
take a dowel (shown in dotted lines
at the bottom of Fig. 3), which runs
up into the post or pillar b.

This post is about | in. square
and about 5| in. high, and it carries
at its top a cross-piece c shaped as
in the detail plan (Fig. 5), where full
dimensions are given. The connec-
tion here, also, is by means of a dowel,
as shown, for which a hole will need
to be bored with a twist bit and a suit-
able piece of round rod prepared and
well glued in. An excellent alternative
to the dowel would be a stub-tenon at
each end of the pillar, with a mortise in
base and cross-piece to correspond.

139

-Front Eleva-
tion of Toy Gymnast

Every Boy His Own Mechanic

The exact shape of the cross-piece is of importance,
inasmuch as this part is a fulcrum on which the levers
work. You will recognise the levers as belonging to the
" first order." The horns of the recesses in the cross-
piece keep the levers upright^ but you will note that the

J C

Figs. 3 and 4. — Two Elevations of Gymnast's Stand

bases of the recesses are not quite flat, but there is a
little projection in the centre on which the levers can be
rocked a trifle. You will understand this more clearly
from Fig. 6, which is a large-scale detail section from which
it will be apparent that the lever d is free to rock a little
on the cross-piece c.

The levers d are shown in a number of the views.

Making Simple Wooden Toys

They are 16 in. long, | in. \vide, and f in. thick. At a
distance of 5| in. from the lower end a hole is bored
through the thickness to take a wire nail — a fairly stout
one, about 1 J in. long. The nails must not fit the holes in
the levers tightly, and the holes must be countersunk to
take the heads of the nails. Preferably, also, the holes
should widen out towards the heads of the nail so that the
lever can rock easily. At I in. from the top of the lever
are two fine holes | in. apart to take the string, as shown
by the dotted lines in the detail plan (Fig. 1).

rLS)

•s

T ' -

Fig. 5.— Pla
for Toy

n of C
Gymn

rossbar
ast

Fig. 6. — Diagram showing how
Levers rock on Crossbar

The figure or puppet must be made of tough wood,
preferably not more than ^ in. thick. The kind of pear-
wood used frequently for cheap set squares is one of the
best materials for the purpose. The figure is in five parts
— the head and body, two legs, and two arms, and it can
be ornamented with ink or stain or with a touch or two
of paint. The pattern for body, leg, and arm respectively
are given by Figs. 7, 8 and 9. There are two holes in the
body, one hole in each leg, one in each shoulder, and three
in each hand. The leg and shoulder holes take the wire
pivots.

The largest of the three holes in the hand^ — that

141

Every Boy His Own Mechanic

shown by the little circle in Fig. 9 — takes a tiny piece of
matchstick {see e. Fig. 2), which keeps the hands apart
and assists the action of the toy. The two fine holes in
the hands take the string, which actually is a piece of fine,
but thoroughly good catgut (an " A " violin string a few
inches long), which should be threaded through and
tied exactly as shown in the detail plan. Fig. 1. It is
wise to drill all the holes before cutting the pieces to
shape.

There is one point of particular importance in assemb-
ling the figure. Fig. 7 shows in dotted lines the exact
positions of the arms. Their length and position on the
body should be such that when the gymnast is raised
above the catgut his body can come forward over the
string and between his hands, trailing his legs after him.

The parts of the body can be shaped with fretsaw
and knife, and cleaned up with glasspaper.

The pivots are pieces of wire, such as fine hairpin, on
which " heads " have been formed by making tiny loops
by means of fine-pointed pliers, these loops being bent at
right angles to the wire and flat against the body of the
puppet. In making these pivots, the head, as described,
would be formed on one end of the wire, the leg, body,
and second leg threaded up, the wire cut off to within
about I in. or so, and a second head formed and bent over.
The arms are put on in the same way, but between each
arm and the body is a small bead (slightly thicker than
the wood of wliich the puppet is made) threaded on the
wire as indicated in Fig. 2. If these beads are omitted,
it will be found that the legs will be continually getting
jammed between the arms and the body. The distance

142

Making Simple Wooden Toys

piece E (Fig. 2) will not be glued in until the arms have
been threaded to the body.

You will need a little help in the suspension of the
puppet. Holding it upside down with the holes in the
hands opposite those in the levers, thread the two ends
of the gut straight through lever, hand, hand and lever,
without any crossing, and tie the ends together ; then,

■-,'-.8- A- '

Fig. 7.— Body Pattern Fig. 8.— Leg Pattern Fig. 9.— Arm Pattern

when the figure is allowed to drop, the gut will cross
exactly as shown in the detail (Fig. 1).

The best finish for the toy is a good coat of varnish,
but there is no reason why you should not paint it in some
attractive colours if you so wish. Varnish or painting
should be done before threading together the parts of the
figure or suspending it in place.

A Toy Aeroplane. — You will reaUsc at once that the
aeroplane shown in the plate already referred to and in
side elevation and plan by Figs. 10 and 11 is not a model

143

Every Boy His Own Mechanic

but merely a toy, which, by means of a string tied to a
ring in front of the propeller, can be pulled about by
your small brother and sister, who will occasionally have
the joy, should the speed be great enough or a wind be
blowing, of seeing the propeller revolve. The toy consists
chiefly of the body a with rudder b, propeller f (we ought

Fig. 10. — Elevation of Toy Aeroplane

t- / ^

::^

Z'-^'r/'^

Fig. 11. — Plan of Toy Aeroplane

really to call it a tractor, I suppose), with planes c
and E mounted on an axle d to the ends of which are
screwed wheels. I show how the whole of the toy can
be made in wood, which will look all the better and be
all the more pleasing to its owner if brightly painted.

Let us take the body first. It is 9^ in. long. If in.
high, and its greatest thickness is 1| in. It is shaped with

144

EASY TOY MAKING

A Toy Gymnast

{See pages 139 to 143 for
Working Diaivinos)

A Toy Tank

{See pnges 14S to 151 for Working Draw'iiigs)

A Toy Aeroplane

(Sfr piiges 144 Ai 147 /.T ]\'iuinng Draiviiigs)

For iiifoniiation on nniliing these toys, see pages 13S to 152

Making Simple Wooden Toys

saw and plane or knife. You will see that, as illustrated,
it tapers at the tail end, where it is only f in. square.
At its front or nose, where the propeller is attached, it is
about I in. square. These dimensions will be found to
give a good effect, but if you can improve upon them, or
if you have some stuff at hand of other and equally

convenient size, I see no objection to your making any
reasonable modifica-
tions that occur to you.
For example, if you

were making two or

three toys of this sort,

you might wish to save

time by keeping the

body of the same width

from front to back, and

you could easily cut

two bodies out of a

piece of f-in. stuff,

roughly 10 in. long, and

2f in. wide. A slant-
ing cut, as shown in

Fig. 12. — Cutting two Aeroplane
Bodies from one piece

■f^ 2"t vk U A

Fig. 13. — Setting out Rudders

J\.

Fig. 14.— Setting out Planes

Fig. 12, would make two bodies from such a piece. Simi-
larly a strip of three-ply stuff, 3 in. wide, could be divided
up, as shown in Fig. 13, and cut up without wasting a bit
of it into rudders, which could be left pointed or could be
easily rounded with a knife.

The rudder is only such in name. As shown at b, it

is simply a piece of flat wood (three-ply is the strongest

for the purpose) glued and nailed into a slot or notch

sawn in the body. Suitable dimensions are shown in the

K 145

Every Boy His Own Mechanic

illustration (Fig. 10). Note that the fish-tail shape keeps
the rear of the body off the ground. Just in front of
the rudder b is the elevator plane e, about 3 in. long
and 1 in. wide, made of three-ply stuff, and glued and
nailed to the body.

As for the front planes c, these are 8 in. long and 2 in.
wide, and the thickness can be about J in., but any three-
ply stuff can be used, and a strip of it, 2 in. wide, can be
economically set out and sawn up, as in Fig. 14. System
in setting out means economy when you are making two
or three toys of the same pattern at one time. The lower
plane is nailed to the axle below it, and also to the under-
side of the body above it. But before the nailing is done,
holes need to be bored through both planes to receive the
vertical struts which support the upper plane. I show
only three such struts, but more would look better. They
may consist of wooden rods about ^ in. thick and about
3 in. or 3| in. in total length. They should fit the holes
in the top and bottom planes tightly, and be glued in
place.

The axle should be about 5 in. long and | in. deep.
The shape and thickness do not matter, but the shape
given in Fig. 15 may be adopted if you like. At each end
of the axle is a wheel which may be of cast iron — a type
that can be bought at many ironmonger's shops very
cheaply indeed — or the wheels may be cut from cotton
reels or from any cylindrical wood.

The propeller f (Fig. 10) should be set out on a piece
of three-ply to a length of 5 in. {see the pattern, Fig. 16),
and width of | in., and cut to shape with saw, afterwards
cleaning up with glasspaper. Two pieces of wood or

146

Making Simple Wooden Toys

metal of the shape shown in Fig. 17 can be joined together
at right angles to give a good effect.

We must remember that, as I said before, this aeroplane
is merely a toy, not a model, and therefore should not be
finished model-fashion. It is for the use of a little child,
and the grey paint which in your eyes would make it
so much the more professional is not to be thought of.
Rub over all rough edges and surfaces with glasspaper,
give it a second rub-

l«-/^-^

Fig. 15. — Front Elevation of
Toy Aeroplane Axle

Fig. 16. — Wooden Propeller

Fig. 17. — Pattern for Metal Propeller

bing with a finer
paper, dust it, and
then paint it in some
attractive colours,
making the rudder,
the axle, and the pro-
peller of different
colours from the body.
Two or three sample
tins of the well-known
enamels which can
be bought very cheaply will enable you to arrive at some
startling effects, which will give great joy to the small
person for whom the model is intended.

A Toy " Tank." — A substantial, if by no means
pretty, toy is shown in the third photograph on the plale
already referred to. This toy is as close a representation
of its dreaded original as an article constructed almost
whoUy of wood, and intended merely as a plaything, can
be made. There are no travelling belts which would
render the toy more realistic, but these belts would be
only in the way on a toy for a little boy's use, and had

147

Every Boy His Own Mechanic

best be omitted. However, you can exercise your in-
genuity if you so wish, and easily devise an arrangement
for carrying the belts if you think tlie trouble and expense
are worth it.

Fig. 18. — Part Elevation and Part Section of Toy " Tank"

Fig. 19.— Plan of Toy " Tank " with Cover of Middle
Cabin removed

You will be able to get all details of the construction
of the toy from the part elevation and part section (Fig.
18), and from the plan (Fig. 19). In the first of these
diagrams it is assumed that the front side has been re-
moved, and in the second that the cover of the middle
cabin has been taken off. The actual centres and dimen-
sions for setting out the sides are given in Fig. 20.

148

Making Simple Wooden Toys

Let us consider the sides first. Each is a piece of
stuff at least | in. thick (it might be even thicker), not
less than 3^ in. wide or less than 7| in. long. As the
exact shape or contour is such a big factor in the toy,
you had better take the trouble of setting it out on a
piece of cardboard first, and you can then cut the card-
board carefully to the outline and use it as a pattern or
template for laying down on the wood. Some boys are
remarkably good at catching the proportions and general

Fig. 20.— Setting out Sides, etc., of Toy "Tank"

shape of an outline, but most readers will need the assist-
ance of the diagram given in Fig. 20. Draw the base
line, and then set up the perpendiculars a and b, which
are 6 in. apart. The centre c is 2 in., and d is 1 in., from
the base line. Join c and d. Setting your compasses to
a radius of | in., strike arcs from d and c, and from these
draw slanting lines to the base line as shown. Bisect the
line c D by means of the line e, which, of course, will be
at right angles to it, and continue e right through the base
line and mark a point at a distance of 41 in. below c d.
This is the centre for the top curve, which should be
drawn in so as to connect up the circular ends. The
oblong piece shown in Fig. 20 is one of the side cabins.

149

Every Boy His Own Mechanic

The pattern or template should be laid down upon the
planed wood, and a line pencilled round. A bow saw
would cut the curve quite well, but if you do not possess
one you must do the best you can by nibbling off bits
here and there with an ordinar}^ saw and afterwards
shaping with knife and chisel, finishing with coarse,
medium and fine glasspaper in the order given. One
face of the wood you are using is probably better than
the other, and it will be well to lay the pattern on upside
down when marking out the second side, so as to ensure
that the parts of the sides that show have the best possible
appearance.

On each side is nailed a little cabin, of which Fig. 21
is the inner elevation and Fig. 22 the cross-section. You
will note that the gun is suspended so as to move slightly
when the " tank " is pulled along. Each side cabin
consists of one piece of wood, 2| in. by If in. by | in.
thick, and in each are bored two holes. One of these
holes is bored from the inside face, and has a diameter
of 2 in. Really it is a recess going only about three-
quarters of the way through. The other hole is simply
a gun port through the front of the cabin to connect with
the recess. I have mentioned the two holes in this order,
but, as a matter of fact, in boring it would be better to
make the small hole (| in. or | in. in diameter) first, and
then cut the recess with a big centrebit. The precise
size of the recess is of no importance. Of course, in making
the two side cabins you will recognise that they must be
a pair ; in other words, one must be made on a different
" hand " from the other.

The dummy guns are pieces of round rod suspended

150

Making Simple Wooden Toys

by a wire in such a way that they can roll quite freely.
Tiny screw-eyes can support the wires, or small holes
can be drilled and a looped wire inserted and clenched
over on the top. The side cabins should not be nailed
on until the inside cabin and the bottom have been fixed.

The " tank " is held together by means of a bottom f
and centre cabin g h, to which the sides are nailed. The
bottom F is 2 in. wide, from | in. to f in. thick, and about
9 in. long. Two holes can be bored through the back

Fig. 21. — Elevation of

" Tank's " Side Cabin,

showing Inner Side

Fig. 22. — Cross Section

through "Tank's"

Side Cabin

part as shown, but their only purpose is to lighten the
appearance. On the bottom are nailed back and front
walls G and h to the centre cabin. Their height is If in.
or 2 in., and the width must agree with that of the bottom.
In the front wall is bored a hole through which the dummy
gun projects. The top or cover to the cabin is a piece of
similar stuff to the walls, 4 in. long, and a recess is bored
in its underside to give play or freedom to the dummy
gun J, which swings to and fro. The gun is of round rod,
and suspended on wires in the manner illustrated. The
cover is nailed down on the cabin walls.

You will take great care that in putting together the
" tank " you get the bottom slightly on the slope. The

151

Every Boy His Own Mechanic

amount of the slope will largely depend on the size of
the rear wheels you are using, and it should be sufficient
to give clearance to the wooden roller l, which works
between the sides, and is pivoted on two wire nails. The
back wheels are mounted on a stout wire, roughly 3 in.
long, or a wooden axle may be nailed or screwed to the
bottom if preferred.

>52

PAINTING, ENAMELLING, AND STAINING

Painting. — Most things that you make in wood need
to be finished with a coat of paint or varnish. Anybody
can put on paint, say you. Yes, I think anybody can,
but what is necessary is to use the right kind of paint
and put it on properly. Now, the first essential is a
good brush. A little more money spent on the brush at
the start and a little more care taken with it in use will
mean far better work than can be done with a poor
brush, which will lose its hairs continually as the painting
progresses and will leave the painted surface covered with
ugly brush marks. What the painter calls a " fitch "
with hog-hair bristles, a flat brush of the same material,
a good-quality sash tool — that is, a brush specially shaped
for painting narrow sash bars, etc. — an oval brush or
either of the last-named " ground," that is, bevelled to
an edge — any of these is an excellent paint brush for
general use, and you can work wonders with a small
and a large sash tool.

When you get a new brush, and you have some rough-
and-ready work waiting to be done, you can go straight
ahead with it, because the rough painting will do the
brush a lot of good, and get it into condition for better
jobs. Workmen often get a new brush into condition
by using it for a day or two for painting brick walls.

153

Every Boy His Own Mechanic

Do not forget that when the job is over and if the brush
is not to be used again for some time, it should be rinsed
out in turpentine to remove the paint and then thoroughly
well washed with soap and water — very little water at
first, but plenty of soap, afterwards increasing the water
until the soap lathers freely. Next, the brush should be
rinsed out under the water tap, shaken free of water,
allowed to dry, wrapped up in paper, and put away till
wanted. If, on the other hand, the brush will be wanted
for use next day, keep it with just its bristles, and only
the bristles., immersed in linseed oil or in a mixture of
linseed oil and turpentine, tying a string round the handle
and so suspending the brush that the weight does not
come on the bristles. Should the bristles be mounted
in tin or other metal, always keep the metal out of the
liquid.

A new brush of the quality used by a workman is
too long in the bristle for use, and it is customary to tie
string round the bristles at the part where they are secured
to the handle so as, in effect, to make them shorter. Then,
as they wear down, the string is undone turn by turn.
I do not suppose, though, that you will take the trouble
to do this, but always remember that the professional
painter gets his good results very largely because he is
willing to spend time on such details.

Any pot will do to hold the paint, and nowadays the
best oilshops, and, of course, the decorators' supply
houses, sell paint put up in cans having very convenient
handles so that the can itself acts as a paint pot.

Mixing up your own paint is probably out of the
question. You will buy a good quality ready-prepared

154

Painting, Enamelling, and Staining

paint, which, believe me, is far superior to anything you
can make at home. But as I like to explain the why and
wherefore of things as I go along, I may explain what an
oil paint actually is. It is a pigment — what you may
know as a " colour " — or a mixture of pigments worked
up with a suitable liquid so that it can be spread over
the work to be painted. Very frequently the pigment
has a metallic base, for examples, white lead, red lead,
zinc white, red oxide of iron, etc., or it may be a coloured
earth, such as ochre, umber, etc. The principal liquid in
the paint is linseed oil, or similar oil, which, when drying,
forms a tough elastic coat which protects everything it
covers from the effects of the atmosphere. The pigment
gives some protection also and supplies the colour. To
make the paint workable and to give it a nice consistency,
turpentine is added. A further ingredient — the driers —
may be added to assist the paint to dry quickly, but you
will remember that the drying of paint is not like the
drying of a wet coat. It is simply the combining of the
oil of the paint with the oxygen of the air, and not a simple
evaporation.

On new wood paint has a way of sinking in, and
leaving a very unsatisfactory surface, and no amount of
daubing on the paint at the outset will get a really good
effect if only one coat is used. If you have made a kennel,
a cupboard, or a boat, and have put some weeks, or per-
haps months, of work into it, surely it is worth while
putting in a few extra hours in order to execute the painting
properly, and so I advise you not to be content with just
one coat. For the first coat, use the prepared paint just
as you receive it, having previously rubbed down all the

^55

Every Boy His Own Mechanic

surfaces with glasspaper. Allow at least twenty-four
hours for the paint to dry (it will not be really dry, but
will be sufficiently hard for the purpose), and then go over
the work with some putty or painter's stopping, and fill
in all little holes made by punching in the heads of nails,
etc. etc., using for the purpose an old blunt table-knife.
The stopping is made by mixing I lb. of putty with 2 oz.
of paste white lead (white lead ground in oil). Now
putty, which is only whiting or ground chalk and oil, can
be safely held in the hand, as it is quite harmless, but
white lead, or any mixture of it. should always be held
on a little board of wood, as all the lead compounds affect
the human body injuriously.

If you have had to do much stopping up of crevices,
you had better leave the work another twenty-four hours.
But if only an occasional nail-hole has had to be filled
up, you can go ahead at once. Gently rub the whole
job down with a piece of worn glasspaper and apply a
second coat of paint, this time mixing a little turpen-
tine with it. This thinning will make the paint flow
more easily, and will assist it in combining with the
first coat. Allow another twenty-four hours at least, and
you can then give the third and final coat, this time
using the paint as it is, and without any extra
turpentine.

Enamelling:. — Some of the nicest paint on the market
goes by the name of enamel. This is really a very fine
pigment or colour ground up with a suitable varnish, and
I know that its use will appeal to you. Unfortunately,
people suppose that enamelling is childishly easy, and
they proceed to daub the stuff on where it is wanted,

156

Painting, Enamelling, and Staining

and often where it is not wanted, so generously that it
runs down in " tears " like so much treacle. Such sloppy
work is unworthy of the boy mechanic. It is not difficult,
I admit, to get a showy effect with enamel paint, but
please take the trouble of preparing the work properly
and of applying the enamel carefully. If your pocket
affords, get a really good brush for the job, or use one
that has been well broken in. Sometimes at a second-
hand shop I have seen good paint brushes, one-third or
one-half worn, to be had for just about the same propor-
tion of their original price. Such a brush thoroughly
well washed with soap and water, rinsed and dried, would
make a first-rate enamel brush. If you buy a new one,
get a brush especially made for varnish. Thoroughly
prepare the work in the first place with worn glasspaper,
and if you are intent upon getting a result of which you
may well be proud you will need to buy at the same
time as you purchase the enamel a tin of the special
" undercoating " made by the enamel manufacturer
especially for use with his enamel. Apply two or three
coats of this special preparation, allowing full time for
each coat to get hard, and gently rubbing each down with
worn glasspaper and wiping over with a duster before
proceeding farther. On such a basis as this you will
get a very fine finish, and if you are out for something
very special, you can apply a second coat of the
enamel.

Perhaps you do know that not all enamel is glossy.
Some of it dries with what is known as a " flat," that is,
a lustreless finish, or with the very slightest shine re-
sembling that on a new-laid egg. The use of a flat enamel

157

Every Boy His Own Mechanic

on a piece of furniture is generally preferable to that of
the glossy kind.

Always, in enamelHng, avoid dust. Don't do the
work in a dusty room, and don't let the brushes and
enamel lie about and get gritty. Keep everything as
clean as you can. Pour a little of the enamel out into a
small vessel, and use it all up before taking more from
the tin. Another important point is, try to strike the
^^PPy medium by applying not so much as will run down
in tears or form wavy lines, and not so little as to cause
the brush marks to show and give a patchy effect. The
advice is quite easily given, but there is more in putting
it into practice than you might suppose. Finally, don't
brush or work the enamel too much in applying it. The
fewer the strokes of the brush the better.

Staining^. — Now this is a very different process of
colouring wood. It adds nothing to the surface, but is
simply a method of dyeing the outer skin of the wood.
The old-time craftsmen were very clever in concocting
vegetable stains, and the beauty of their effects has never
been surpassed, but nowadays only the few still go to
the trouble of making their own stains, and most people
rely upon various forms of aniline colours, a variety of
which can be bought in cheap packet form. As a rule,
directions are printed on the packets, and they amount
to little more than adding hot or cold water, with perhaps
a little vinegar, to the powder, although many of them
(those known as "spirit soluble") require the addition
of spirits of wine or the far cheaper methylated spirit,
which is practically the same thing with the addition of
some nasty-tasting mineral spirit to render it objectionable

158

Painting, Enamelling, and Staining

to the palate. Aniline dyes can be applied with brush,
or sponge, and will be found excellent for general use,
although the brighter colours, particularly the reds, are
fugitive— in other words, they bleach— in direct sunlight.
Bichromate of potash and permanganate of potash,
respectively, dissolved in hot water make fine rich stains,
and coat after coat can be applied until the right tone is
reached.

An excellent walnut stain is made by stewing some
green walnut peel in water and applying two or three
coats of the liquid to the wood in a warm room. When
nearly dry, give it a coat of bichromate of potash solution.

To make wood resemble the tone of dark oak, apply
some brunswick black considerably thinned with tur-
pentine.

For a mahogany stain dissolve 1 oz. of dragon's blood
(a gum you can buy at an oilshop) in 1 pint of turpentine.
Stand the bottle in a warm place and shake it frequently.

Most of you know the term "fumed oak." The
fuming or fumigation of oak is an interesting process, but
not all oak is susceptible to the action of the ammonia
used for the purpose. Some varieties of mahogany also
can be treated in this way. To find out whether a piece
of wood can be darkened by fuming, place a portion of it
over the mouth of a bottle containing liquor ammonia (the
so-called " hquid ammonia "), the stopper having been
removed. If the wood is susceptible, its colour will soon
darken. The work must be quite clean from grease or
the marks of the hands. If you are using a good-sized
packing case as the fumigating apartment, place a saucer-
ful of liquor ammoniae on the floor of the case, then insert

»S9

Every Boy His Own Mechanic

the articles, but not so that they touch the liquid, close
the lid, and stop the joints by pasting on strips of brown
paper. The longer the wood is left in the case the darker
will it become. Wiping over with diluted liquor am-
moniae will have a darkening effect upon any wood that
is susceptible of the other treatment, but the true fuming
method has one great advantage over the use of liquid
stains — it does not raise the grain of the wood. Generally,
after the use of a liquid stain, it is necessary, if a good
finish is required, to go all over the work with glasspaper
to remove the portions of the wood fibres swollen and
raised by the liquid.

The oilshops sell a mixture known as " combined
stain and varnish," and you may be tempted to use it.
It may do for a common job, but not for anything which
you prize, as the effect is rather cheap and nasty. The
boy mechanic may be entrusted with the job of staining
a floor margin, and may resort to the stuff as being the
easiest and quickest for his purpose, but he will get a far
better effect and a more lasting one by getting some oak,
walnut, or mahogany stain in liquid or powder form,
giving it twenty-four or forty-eight hours after appli-
cation to get dry, then applying a coat of size, and
finally a good flowing coat of oil varnish purchased from
a reliable firm.

:f*o

FRETWORK IN WOOD

Most people associate fretwork with those fantastic
and often fragile articles which sometimes ornament
cottage parlours — photograph frames that dwarf the
photographs, model " tanks " and locomotives grotesque
to the point of absurdity, clock cases and brackets that
nobody dare dust, and so on. Fretwork has suffered from
two causes — poor designs and their wrong application. It
is restricted in its
scope, but the zealous
fretcutter has not
recognised any limita-
tions and has applied
his ornament to any-
thing and everything
that can be made of
wood. Fretwork can
be made very beau-
tiful and can be
extended to ivory, celluloid and various metals.
I shall give in this chapter a few designs (see
Figs. 2, 6, 7, 8 and 10) that, in my opinion, will
occasion but little reproach. Let me first talk of
fretwork in wood, and leave the finer work in metal
to a later chapter.

Fig. I. — Fretsaw

Every Boy His Own Mechanic

Saws. — The saw may be hand or machine, the ad-
vantages of the latter being greater speed of cutting, less
fatigue, and freedom of both hands to guide and control
the work. Suitable machines are shown in variety in
any dealer's catalogue. In use keep the machine clean
and oil all the bearings often but sparingly; a suitable
lubricant is cycle oil of a thick variety.

The hand saw may resemble Figs. 1 and 3, or may be
one of the many other patterns available. The sweep
of the frame should not be less than 12 in. or more than
18 in. In selecting a frame, see that the clamps which
hold the blade in tension are good and work well. The
best type of clamping arrangement is that in which the
blade is simply inserted and then tightened up by giving
the handle a turn. Something quick and easy is required
because the saw has frequently to be threaded through
holes drilled in the work, for which reason the blade has
to be undamped every time. Remember one point :
so thread the blade that the teeth cut on the downstroke,
otherwise the sawdust will obscure the lines of the pattern,
and a swarf be raised on the paper which will make it
difficult to follow the lines ; this means that the working
stroke is the pull and not the push, as the controlling
hand is underneath the work. When a fretsaw, usually
a machine saw, cuts on the upstroke, a blowing device
is employed to keep the pattern free of sawdust.

With regard to saw-blades, buy the best. The differ-
ence in price between the good and the bad is so little
as not to be worth considering, whilst a poor, slow-cutting
soft blade which soon bends or an over-hardened one that
soon breaks when in use is a nuisance and may mean the

162

Fig. 2. — Design for "Oval" Frame in Fretwork

{A and B show respectivdy a difficult and comparatively easy detail
of forming the rebated edge)

163

Every Boy His Own Mechanic

fracture of delicate detail. Rounded-back blades of the

best quality will give the greatest satisfaction.

Other Equipment. — Work is held for sawing by means

of a cutting board,
which is either per-
manently screwed to
the bench or fitted
with a clamp for
attachment to bench
or table. The usual
shape is shown in
Fig. 3.— How to Hold a Fretsaw Fig. 4, the V-lK)tch

accommodating the saw blade when at work. This

figure shows a table or bench especially designed

for fretworkers' use. Perhaps you can pick up a light

table for a few shillings and screw on a notched

cutting-board, and, if

necessary, shorten the legs

by an inch or two so that

as you sit at your work

the table-top is at such a

height that your left hand

easily rests upon it, while

your right works the saw ^Wf| x^jj

from underneath. Then, if """^

a small vice (as in Fig. 4) c^

can be attached at one end, p;g 4._Fretworker's Table with
you will have a serviceable Cutting-board and Vice

and comfortable bench for fretwork and similar light opera-
tions; but don't attempt to use it for carpentry work, as
it will not be solid or heavy enough for planing upon.

164

Fretwork in Wood

Besides the usual tools and accessories — hammer, fine-
toothed ordinary saw, pincers, small screwdriver, chisel,
small nails or " pins," seccotine, gluepot, etc. — which most
boy mechanics are almost certain to possess, you will
need a special tool for drilling or boring holes in the work
to give a start for the saw in enclosed parts of the design.
A bradawl or even a gimlet — anything
with a wedge-shaped point — will only split
the work as a rule. The proper tool is the
drill named after your dear old class-room
friend Archimedes, its twisted stem resem-
bling the famous hollow screw which the
ancient Greek invented (about 260 years
B.C.) for the purpose of raising water. The
twisted stem rotates in a bearing formed
in the handle {see Fig. 5), and is given
motion by pressing down the bobbin through
which the stem is threaded. The bottom
end of the stem carries a chuck (vice) to
hold a drill-bit. A good type of archime-
dean drill has a small spring in the handle
to assist the withdrawal of the bit ; another
improved pattern facilitates speedy work —
it carries balance weights just above the
chuck, the momentum which they gain on the down
stroke of the bobbin being sufficient to keep the drill
rotating on the idle upstroke.

Another necessity is glasspaper of three grades, Nos.
2, 1| and 1, used respectively for rubbing off pasted-
down designs, cleaning up the surface and finishing the
job; the higher the number of the glasspaper the coarser

•65

Fig. 5. — Archi-
medean Drill
with Chuck
or Holder to
take D ri lis
or Boring
Bits

Every Boy His Own Mechanic

being its grade. The trouble in using glasspaper is that
without great care you find yourself rubbing away the
sharp edges of the wood and losing the effect of good
workmanship. Therefore to obviate this always use the
glasspaper wrapped tightly round a block of wood or cork.

Fig. 6. — Design for Wall Bracket in Fretwork

(The centre support is a repeat of half the bach)

Fretwood. — So far I have not mentioned the material.
Many firms now make a speciality of fretwood, and you
can order from them exactly what you want, so avoiding
waste pieces. Almost every cabinet-making wood is ob-
tainable in suitable thickness — in the neighbourhood of
=j'g in. — for fretwork; and the unit of measurement is the
square foot. Thus, a piece of wood 7 in. wide by 29 in.
long will contain 7 X 29 = 203 sq. in., nearly 1| sq. ft.,
and would be charged for on that basis.

i66

Fretwork in Wood

All fretwork is liable to warp and twist. Wood is
constantly absorbing or giving off moisture according to
the condition of the surrounding atmosphere, and unless
it is suitably secured at the sides or held down by weights
warping is inevit- ^^

able when the fibres rC^ ^.

swell. Two-ply and
three-ply wood has
two or three layers
of thin wood glued
together under
great pressure, one
of them being at
right angles to the
other or others as
regards the direc-
tion of the grain, so
that the grain of
one layer counter-
acts any tendency
of the other layer
to twist out of
shape. Some good
pieces of three-ply
material can often

Fig. 7. — Design for Frame in Fretwork

be obtained from tea-chests, but the faces of the stuff
need to be glasspapered into condition.

The Design or Pattern. — Fretwork designs of the
printed kind are obtainable on thin paper and need to be
pasted down on the wood (but if they can be easily trans-
ferred by means of carbon paper and a hard pencil, so

167

Every Boy His Own Mechanic

much the better, and there will then be no paper needing
to be rubbed off at a later stage). Let the length of the
design run in the direction of the grain. Apply the paste

to the design only, and use
either boiled starch or an
office paste of the " Fixol"
or " Stickphast " types, but
in any case use as little
as will effect the purpose.
Applying the paste to the
wood itself or an excess of
paste on the paper will
raise the grain and pos-
sibly warp the wood. Let
the pasted paper get
thoroughly dry before
starting to use the saw.

Using the Fretsaw. —
The actual fretsawing is a
matter of infinite care and
practice, and not much
need be said concerning it.
Hold down the work firmly
with the left hand, see that
the blade is held taut in
its frame, and firmly grip
the handle in the right
hand, always keeping the
blade perfectly upright and
making uniform, steady
strokes. The right hand
x68

Fig. 8. — Design for Letter Rack
in Fretwork

Fretwork in Wood

simply works the saw up and down, and does not
advance the saw into the wood. The feeding of the
work to the saw is a matter for the left hand, and
this is where most people find the machine saw to
have a great advantage. It is usual to saw out the
inside parts of the pattern before attempting the edges,
because the work is then more easily and safely handled
up to the final stages.

The turning of both inside and outside corners is a
matter for practice. Use fine good saws and plenty of
common sense.

Overlays, Marquetry, etc. —
The modern fretworker is fond
of overlays — fret-cut patterns in
thin stuff glued down on the
face of the work. Very thin
stuff should be placed between
waste stuff, nailed together at
the edges, and the pattern laid
down on the top piece of
waste. This leads to double and
treble cutting — known as plural
cutting — only to be attempted when you have mastered
the correct use of the saw — and to marquetry, which is a
system of ornamentation by which very interesting effects
can be obtained. Two pieces of wood of different colours,
say holly and rosewood, are cut at the same time, care being
taken to keep the sawn edges perfectly square, and to
avoid spoiling any cut-out pieces as might be perfectly
legitimate in ordinary fretwork. Then the parts of the
two designs are interchanged {see Fig. 9) to give good

169

E3(kIE

Fig. 9. — Marquetry Inter-
change Pattern

Every Boy His Own Mechanic

effects, and glued down on the surfaces to be
ornamented, thus forming two companion ornaments
in reverse colours.

Finishing. — For removing the pasted-down design do
not attempt to soak it off. Fretted woodwork cannot

stand water.
Instead, place
it on a per-
fectly smooth
flat surface
and rub it off
with No. 2
glasspaper held
round a block,
finishing with
Nos. 1| and
1 applied suc-
cessively.

By inclin-
ing the saw-
blade inwards
when cutting
out a piece
(a circle, say,
or other simple
figure), the area
of the bottom face of the cut-out part will be made greater
than that of the top of the hole from which it came {see
the section, Fig. 11), and by seccotining the edges and
possibly further securing the part from the back it will be
possible to mount the cut-out part as a bevelled-edge

170

Fig. 10, — Design for Frame in Fretwork

Fretwork in Wood

overlay entirely covering the hole. But good workman-
ship is absolutely essential, as the bevel must be uniform.
In straight-sided patterns, some workers obtain a
uniform bevel by wedging up the fretwork slightly

Fig. 11, — Diagram showing the Use of Bevel-cutting
in Appliqufi or Overlay Work

at one side, the saw blade being kept perfectly
upright, but should the wedges slip the bevel alters.
Some fret-cutting machines have a tilting table which
facilitates the cutting of bevels. Fire-screens can be
well decorated in this manner.

171

GLEANING AND ADJUSTING A BICYCLE

I TAKE it for granted that nearly every boy knows a
great deal about his bicycle, and that in a chapter under
the above heading he will look for information only on
those points in which his acquaintance with his machine
is not likely to have afforded him experience. Still, there
are one or two matters, such as the repairing of a punc-
ture, which I must dwell briefly upon, although to many
my readers instruction on that point will be super-
fluous. I shall take the case of a bicycle that has been
running two or three years^ or which has come secondhand
into your possession, and which would be all the better
for a complete overhauling. True, the professional cycle
repairer could probably do the work better than you can,
but in taking your machine to bits, its mechanical anatomy
will be impressed on your mind in a way you will never
forget, and you will the better be enabled to remedy any
trouble that might occur on the open road.

The Parts of a Bicycle. — Every part of a bicycle
has its own particular name. Look at Fig. 1, and you
will at once identify the chief of its components — the
top tube 1, the down tube or seat tube 2, the bottom
tubci 4, and the head tube 3. In addition, there are the
front fork blades 23 and the back fork blades 15. There
are the front and rear wheels with rims 19, tyres 18,

172

Every Boy His Own Mechanic

spokes 16, valves 17, and spoke nipples 24. To protect
the rider from mud and dust, there are the front mud-
guard 27, with its extension, and the rear mudguard 26.
In the bottom bracket (at the junction of the seat tube
and bottom tube) is the spindle, behind 35, carrying the
chain wheel 21, the chain 20 transmitting the drive to
the chain ring on the hub of the rear wheel. The handle-
bars 7, with handles 8, are one with the steering tube
which is clamped into the fork stem, this being a tube
passing through the head tube 3 ; the lower end of the
fork stem carries the fork crown and fork blades. The
saddle 12, and tool wallet 13 are supported by the seat
pillar 11, which enters and is clamped within the seat
tube 2. In the bicycle illustrated are two rim brakes,
both operated by hand ; 10 is the front brake forket
and 25 the back brake forket, but, as you know, some
bicycles have only one rim brake, and in addition a brake
working within the rear hub and actuated by the chain
when back pressure is applied to the pedals 22. In my
opinion, no safer system of brakes has yet been devised
than the hub-contained type, but there should always be
a front rim brake as well.

Gear." — Most boys will recognise the gear change
control lever 28, and its cable 29, but I find that the
general idea of what is meant by the " gear " of a bicycle
is a very vague one, as well it might be. It is a term that
dates back to those days when our fathers — in some cases
our grandfathers — rode the "ordinary" machine with a
big front wheel and a small back one. If that front wheel
was 60 in. or 56 in. or 64 in. in diameter, then the gear of
the machine was said to be " 60-in./' " 56-in.," or " 64-in."

174

Cleaning and Adjusting a Bicycle

respectively. The distance travelled in one revolution of
the pedals in those old front-driver machines was 3l times
the diameter of the front wheel ; thus a 56-in. wheel
travelled about 176 in. for every complete revolution of
the pedals. Now, if you have a bicycle and by careful
experiment find that one complete revolution of the
pedals drives the machine forward 176 inches, you will
know that your bicycle has a " gear " of 56, but it is an
awkward experiment to carry out, and it is much more
simple to work a little sum instead. Fig. 2 will show you
how to set about it. First count the number of teeth on
the chain wheel. Say it is 50. Take the diameter in
inches of the back wheel ; say this is 22. Multiply the
two together, 50 X 22 = 1100. Divide this by the number
of teeth in the chain ring or sprocket on the back hub ;
assume this to be 18. Then 1100 -^- 18 = 61 and a
fraction^ and the machine is said to have a gear of 61.

The higher the gear, the greater the strength required
to push the machine up-hill or against the wind, and that
is why boys' and ladies' machines are always geared lower
than a man's. But the higher the gear, also, the greater
the speed of the machine per revolution of the pedals,
and the more convenient for running on a slight down-
hill, or with the wind behind you. So it comes to this.
Up-hill you want a low gear. Down-hill you can do with
a high one. And it is this pleasant alternative which
you get by installing a variable gear device or " change-
speed gear," which is a box of cog-wheels built into the
back hub, by means of which the leverage or mechanical
advantage is increased or decreased. Whereas on a fixed
gear machin<? you must negotiate all conditions of road

175

Every Boy His Own Mechanic

and wind at the same gear ratio, on a variable gear machine
you can select one of three (sometimes two) gear ratios to
suit the circumstances of the moment. Now to the
actual business of the overhauling.

The Frams. — If the frame is dirty and mud has dried
on it, don't rub it off violently or you will scratch the
enamel. Sponge it off gently, wipe over with a cloth,

and if you want to improve the appearance of the enamel,

Fig. 2. — Diagram showing how to obtain " Gear " of Bicycle.
Multiply Teeth in B by A, and divide by Teeth in C

rub over with some good furniture cream. If the enamel
is very badly chipped, you may decide to have the frame
re-enamelled, or to give it a coat of air-drying enamel
yourself. Several good makes are sold at any cycle shop,
but you need a superior brush to get a good result, and
more than one coat is advisable. If you have the time,
it pays to rub over the first coat when it is thoroughly
dry and hard with a felt pad sprinkled with fine pumice
powder and moistened with water or oil. The result
will be all the better too, if before the enamelling is

176

BICYCLE CLEANING AND ADJUSTING

Bottom Uracket supported on box for the hammerinj
out of Cotter Bolt

Bicycle Suspended by Rope for ease in Oiling and Adjustment

Cleaning and Adjusting a Bicycle

started you go over the old enamel with some fine
emery paper. The use of some good oil-colour specially
mixed up for you by a coach-painter and followed by a
coat of the best oil varnish would give a better result than
shop-bought " cycle enamel."

Bearingfs. — For cleaning out the bearings, stand the
machine on the saddle and handle-bar, or suspend it by
a couple of ropes from two hooks fixed in the shed roof,
and squirt petrol or paraffin oil into all the bearings
repeatedly, and revolve the wheels so that the cleansing

Fig. 3. — Crank End and
Cotter Bolt

Fig. 4. — Bottom Bracket
with Cotter Bolt

liquid can get everywhere. Paraffin and petrol do not
improve rubber tyres, and if you propose a very copious
application, you had better first remove the tyres. Work
the pedals till all the paraffin, etc., is out, and then lubricate
with good quality cycle oil or pure sperm oil alone.

Test the bearings to see if there is any shake or play
in them, and if there is tighten them up by means of the
thin cone spanner. If you suspect a broken ball in any
of them, listen carefully while the spindle revolves. There
ought to be only the regular noise of the balls touching one
another as they revolve, but if occasionally you hear a
sharp click, you will know that one of the balls is frac-
tured or the cone or cup is faulty. Then you must undo

M 177

Every Boy His Own Mechanic

the bearing with a spanner, but look out for trouble;
and don't do the work on the lawn ; remember that the
steel balls are liable to drop out quite suddenly, and it's
an awful business finding them all. You can get new
steel balls at a cycle shop or even a new ball-bearing cup
in the unlikely event of one being needed, and if you
have trouble — as you are sure to do — in keeping the balls
in position when replacing them, try the effect of smearing
them with plenty of vaseline, which will prevent their
running about, but if you use much vaselinC; wash it out

Fig. 5. — Bottom-bracket Axle or
Spindle and the Cups

afterwards with paraffin oil or petrol, as otherwise in cold
weather the vaseline will be a clog on your progress.

Adjusting the Bottom Bracket. — To make any ad-
justment of the bottom-bracket bearing, it will first be
necessary to take off the crank opposite to the chain side.
Remove the nut (see Fig. 3) with a spanner, support the
end of the crank on a block or anything solid, and drive
out the wedged-in cotter bolt (shown separately) with a
blow or two from a heavy hammer. (In replacing after-
wards, note, of course, that the flat on the cotter will
come against the flat on the axle or spindle, Fig. 5, which
illustration shows the axle and the cups that keep the
balls in place.) The crank having been removed, the cups
are adjusted or removed by first loosening the nut of the
bottom bracket cotter bolt (shown underneath in Fig. 4),

178

Cleaning and Adjusting a Bicycle

and then turning the cup with a pin or peg spanner if
there are two holes in the cup for the purpose, or with an
ordinary spanner if there is a raised part with parallel
edges. In taking out and replacing the balls and axle,
carefully observe the precautions given in the preceding
paragraph.

The Chain. — Removing the chain is a simple pro-
ceeding. Close examination will show that one or two
of the pins consist really of a small screw-bolt and nut,
and one of these may be removed by means of screw-
driver and spanner. Replace the pin and nut in
the loose end of the chain immediately after re-
moval, as otherwise they are easily lost, and it is
better to have at hand a tray in which to place the
various screws and nuts as they are taken from the
machine. All naked chains (those run without a gear-case)
need occasional cleaning. Coil up the chain, place it in a
dish, and pour over it paraffin, or a mixture of paraffin
and petrol, leave it for twenty-four hours, and then hang
up to drain. It is not easy, except by some such method
as the following, to lubricate a chain thoroughly, oiling
in the ordinary way or the rubbing on of chain greases
being too superficial a treatment. It is better to make
the cleaned chain thoroughly dry and place it in a dish
containing Russian tallow or vaseline, or, instead, either
of these mixed with graphite, which has been melted by
heat. If the chain has been made warm, almost hot
before immersion, the tallow will find its way to its in-
ternals. After immersion, hang up the chain to dry, and
wipe off the superfluous fat.

A chain runs far better in a gear-case than it does

179

Every Boy His Own Mechanic

slacken''
Nipples ;
Here

Tighten
Nipples
Hvre

Tighten
i Here

naked, and lasts much longer ; when the gear-case is an
oil-bath, the chain will very rarely require any treatment
whatever. Very occasionally, indeed, a wash-out with
paraffin and the replenishing of the lubricating oil are all
that is necessary. Fig. 6 shows how
to recognise signs of wear in a chain.
Wneels out of Truth. — A frequent
fault in a bicycle that has been in
use for a long time is a lack of truth
in the wheel rims. A fall may have
loosened or broken a spoke, so up-
setting the balance of tension. You
have only to screw up some of the
spokes a little tighter than those on
the opposite side of the hub to
destroy the balance oT

I Slacken
WHJ Here

wheel and

Fig. 7. — Diagram indi-
cating In Dotted Lines
the Sideways Bulging
of a Cycle Wheel

Slacken

Nipples
Here

Fig. 8. — Diagram indicating in Dotted Lines
a Lack of Circularity

i8o

Cleaning and Adjusting a Bicycle

distort the shape of the rim. Rims go out of shape
in two ways — they may cease to be circular (Fig. 8),
or they may bulge sideways (Fig. 7). The last trouble
can be detected by rotating the wheel and support-
ing a piece of chalk at the side on one of the chain
stays quite close to the rim. Then any bulgy part will
be marked by the chalk. By means of a spoke nipple key
costing a trifle, slacken
the nipples in the rim
at the side marked by
the chalk, and on the
opposite side of the rim
tighten up the spokes.
Adjust a little at a time
only, and test constantly
until truth is restored.
It is a job necessitating
care and a nice judgment.
To test whether a
wheel has lost its cir-
cularity— that is, whether
it is out of the round — having first removed the tyre,
rotate the wheel, and fasten a piece of wire across the
forks close to the rim, and mark high places with chalk.
At the parts where the rim bulges tighten up the spokes
on both sides of the rim. Where the rim is low, slacken
them, but be very careful and proceed with the utmost
caution. Should an accident have smashed a spoke, a new
one must be inserted before any tuning up is attempted.
Take the old spoke with you when you buy the new one,
so as to ensure getting the proper length and thickness.

i8i

Fig. 9.— Roller or Friction-type

Free-wheel Clutch : A, chain ring ;

B, balls ; C, rollers ; D, springs ;

F, followers

Every Boy His Own Mechanic

In ordering new chain wheels, hubs, etc., it is necessary
to give the " chain Hne " of the machine. You measure
this from the centre of the rear wheel hub to the centre
of the chain- wheel teeth. Thus a l|-in. chain-line hub
measures that dimension from midway (generally the
centre of the lubricator cap) between the flanges to the
centre of the thickness of the chain-ring or sprocket.

The "tread" of a bicycle is the overall length of the

bottom - bracket axle.
The "wheel base" is the
length of the bicycle be-
tween the centres of the
two road wheels. The
dimension of frame is the
length of the down tube
from its top to the centre
of the bottom bracket,
thus, "20 -in. frame,"
" 24-in. frame," etc.

Pedals. — The replacc-

Fig. 10.-

Pawl and Ratchet Free- . c i i n i i

wheel Clutch ment of an old pedal by

a new one may prove to be a very puzzling business unless
you remember the following : To remove the right-hand
pedal turn the spanner to the left, anti-clockwise. To
remove the left-hand pedal turn the spanner to the right,
clockwise. You can easily see the reason why this should
be so ; the screw-threads in each case are so arranged that
the pressure of the foot tends to tighten the pedal, which
would not be the case if the left-hand pedal had the
ordinary right-hand thread. This hint does not apply to
very old machines.

182

Cleaning and Adjusting a Bicycle

Pedals arc quite easily taken to pieces, as their con-
struction is obvious^ and parts for replacement may be
bought.

Free-wheel Clutches. — Sometimes the free-wheel
clutch in the back hub gives trouble. This may simply
mean that it is choked up with old and dirty oil, but as a
rule, it is a sign that something has worn out. Don't
take it to pieces until you have satisfied yourself by
squirting in plenty of
paraffin or petrol that
the failure is not due to
dirt or gummed-up oil.
Often the trouble is sim-
ply a matter of weak
springs, which can be re-
placed at trifling cost ;
or the friction rollers {see
Fig. 9) may have worn
badly, necessitating the
purchase of new ones.
In the more modern pawl
and ratchet type (Fig.
10), there are few springs and no rollers, and nothing is
likely to go wrong if kept clean and well oiled.

If you have a coaster hub on your machine, and we
know of no more convenient brake, clean it out occa-
sionally in the way described for the free-wheel clutch,
and when all the liquid has drained off, apply plenty of
lubricating oil. If you want to make a really good job of
it, you will need to take the hub apart and see that the
whole of the brake surfaces are amply treated with a very

183

Fig. 11.

-Eccentric-disc Chain
Adjustment

Every Boy His/^Own Mechanic

thick lubricant such as motor cylinder oil, stauffer grease,
or some similar heavy lubricant.

Chain Adjustment. — In putting the machine together
again, see that the chain is correctly adjusted. There
should be a very slight sag both top and bottom, and on
no account should the chain be so loose that it can work
off the sprockets or so tight that it makes the machine
run hard. The method of setting the back wheel farther
away from the bottom bracket is self-explanatory in most
machines, but when for the first time you seek to adjust
a machine having eccentric-disc adjustment (see Fig. 11)
instead of the time-honoured screw-bolt and nut adjusters,
you may be pardoned if you don't understand it at a
glance. Two pairs of eccentric discs, one on each side
are carried on the spindle of the rear wheel, and all that
is necessary to advance the wheel slightly towards the
chain wheel, or to push it farther away, is to loosen the
nuts which hold the rear wheel in place and give the
flattened end of the spindle a slight turn with a spanner.
Not many bicycles have been fitted with this device in
the past, but it possesses many advantages over the old
system.

The Plating. — What is to be done if the plating has
got very rusty ? Not much, I am afraid, but you might
try rubbing the plating with a rag made wet with sweet
oil followed with metal polish. Of course, emery powder
and paraffin oil rubbed on with a rag will remove the rust,
but the plating will not be worth much afterwards, and
then you can do one of three things : (1) Coat the plating
with a cold lacquer such as Zapon, which is one of the cel-
luloid varnishes ; this won't renew the plating, but it will

184

Cleaning and Adjusting a Bicycle

prevent its getting much worse. (2) Give it a couple oi'
coats of one of the metalHc paints, such as aluminium paint,
which is a mixture of aluminium bronze and celluloid
varnish. (3) Go over the whole of the plating with black
enamel, and then pretend that yours is a "special all-
weather" machine! If not one of these three appeals to
you, then I can only suggest that you have all the bright
parts re-plated, which is altogether too big a job to be
done at home, and must be entrusted to a tradesman.

If you are putting your bicycle away for any length
of time, it is wise to smear the plated parts with vaseline,
or, better still, to coat them with cold lacquer, which you
can buy ready-made, or may prepare yourself by mixing
I gill of acetone with | pint of amyl acetate, and in the
mixture dissolving about | oz. of celluloid. Any colour-
less scraps from broken toys, celluloid combs, etc., can be
used. Keep the lacquer tightly stoppered when not in
use.

Removing Tyres. — Finally a brief explanation of
tyre-repairing, a job, I suppose, to which almost every
cyclist has been introduced. A common trouble is for
the tyre to get soft within a few hours of pumping up.
The job is first to remove the outer cover, next to find the
puncture, then to repair it, and finally to replace the
cover. But first make certain the valve is not at fault.
Rotate the wheel until the valve is at the top, and then
lift a wineglass or egg-cup nearly full of water so that the
valve is immersed. Bubbles of air immediately betray
a leaky valve, and a new valve rubber will then be
necessary.

You will know that some covers have wire edges

185

Every Boy His Own Mechanic

(Fig. 12) whilst others are simply thickened up or beaded
(Fig. 13), the second being more easily removed and
replaced than the first. Remove the valve stem by un-
screwing the nut so as to empty the tyre. The tools for
removing the cover may be a set of special tyre levers
bent and notched, which are very convenient, or may be
the handles of two old tooth brushes. Starting at a point
diametrically opposite the valve, insert two levers about
4 or 5 in. apart under the tyre edges, and apply leverage
so that the edge is lifted off the rim. Then by holding

Fig. 12. — Wired-edge Tyre Fig. 13. — Beaded-edge Tyre

down one lever or catching a notched lever on a spoke,
the other can be slid along and the edge released all the
way round. The job is sometimes very much more difficult
than the above explanation might suggest, very much
depending upon the fit of the tyre and how long it takes
you to acquire the knack. Some people can use smooth
pennies as tyre removers, and others can do the work
without any tools at all except their fingers. Others
again, use screw-drivers and cut up the outer cover, and
stab holes in the tube !

Patching the Tubes. — Now pull out the inner tube.
Replace the valve stem and nut, and partly inflate. Have
at hand a bowl of water on a stool, and pass the tube a

1 86

Cleaning and Adjusting a Bicycle

few inches at a time through the water, slightly stretching
the rubber as you go. There will be no doubt as to
whether there is a puncture when you arrive at it. There
will be a stream of bubbles rising from the tyre to the
surface of the water. Sometimes a tyre is punctured in
two distinct places at the same time, and it is generally
wise to test the whole of it. Mark the puncture when
found with chalk or pencil, and wipe dry.

We are now going to cement on a little patch., but
there is a white powdery stuff on the surface of the rubber
to which the cement or solution does not readily adhere,
so the first thing to do is to dress round the puncture
with glasspaper or emery paper until good solid rubber
is reached. From a tube of solution (pure unvulcanised
rubber shredded and dissolved in pure benzine), squeeze out
a blob, and rub it thinly over the dressed surface with a
match-stick. Have at hand a piece of old rubber tyre, or,
better still, a piece of patching rubber, which is a reason-
ably cheap material. Coat this with solution thinly in
the same way; first, in the case of old rubber, working
over it with glasspaper or emery paper as before.

The whole point of the operation is contained in the
next instruction. Do not bring the patch into its position
yet awhile. Let it wait until the solution is almost dry.
Actually, it will be what is known as " tacky," that is,
although it will appear to be dry, it will adhere to the
thumb-nail rather forcibly. Not until this stage is
reached should the patch be put on, and if you are doing
the work for the first time you will be surprised at the
way in which the two solutioned surfaces cling together.
It is with difficulty that they can be torn apart. Press

187

Every Boy His Own Mechanic

the two to exptl any bubbles of air, and dust all over
plentifully with french chalk so as to destroy the
adhesiveness of any solution remaining at the margin of
the patch.

Cover Repairing. — Next work the fingers all round the
inside of the outer cover slowly and carefully to try to find
any nail, sharp flint, etc., that may have caused the punc-
ture. Failure to do this is simply to run the risk of another
puncture almost immediately.

If the cover is faulty, with a nasty cut on the outside
where a flint or piece of glass has entered, it, too, should
be repaired thoroughly. Clean it with a rag or old tooth-
brush dipped in petrol or benzine (avoid the use of paraffin
on tyres), and then work into the cut one, two or three
coats of solution, allowing about a quarter of an hour
between them, so that one may dry before the next is
applied. At the cycle depot, you can purchase some soft
prepared rubber known as "tyre stopping," and a little
of this can be well pressed into the prepared cut, and
left for at least a day or two before the tyre is used. If
you cannot get tyre stopping, you can make a fair sub-
stitute by mixing some cotton wool with rubber solution.

If the fabric on the underside of the cover has rotted
or been badly damaged, it will be only a waste of time to
stop the cut unless you also go to the trouble of cementing
some new canvas in position at the back. Use a fairly
large piece of the specially proofed canvas obtainable at a
cycle depot; clean the place with petrol, apply a coat of
solution to cover the proofed side of the canvas, and
allow to dry. Then apply a second coat, and when the
right condition of tackiness is reached, bring the two

1 88

Cleaning and Adjusting a Bicycle

together and firmly press. Use plenty of french chalk
to kill any surplus solution, as otherwise when the
cover is replaced the tyre might stick to it and cause
a burst.

Replacing the Tyre. — Tube and cover having been
thoroughly overhauled, we have next to get the tube
back into its position. First place the valve tube through
the hole in the rim and carefully work the tube into
position. Tuck in the cover at the valve, and for a foot
each side of it, and slightly screw up the lock-nut on the
valve so that the cover can move only slightly.

In putting a new rubber sleeve on a valve stem,
slightly wet the metal and insert it into the sleeve with
a twisting motion. Screw up the valve nuts tight.

The one thing to be watched for in replacing the cover
is to avoid pinching the tube. Pinches mean ugly gashes
and repeated exasperation

With the fingers work the cover into position al-
ternately on each side of the valve until only a few inches
remain to be got into place. Sometimes the fingers are
alone sufficient to finish the job. but generally some
amount of persuasion with a smooth lever is necessary to
get the edge over the rim. Fit up the valve completely,
tighten the lock-nut, and give a few strokes to the pump
so as very slightly to inflate the tyre. Now go carefully
round the rim with the fingers and make certain that the
tube is not nipped anywhere. Thus assured, you can
give a few more strokes to the pump or even inflate fully.

New tape should be put round the rim over the spoke
heads when necessary, as this is a great protection to the
rubber tube, iron rust having a bad effect on rubber.

189

GILDING WITH GOLD LEAF AND
GOLD PAINT

In the decoration of picture frames and other work not
many boy mechanics will aspire to real gilding, so I pro-
pose to touch upon it only briefly. The gold in a variety
of colours is obtainable in the form of leaf. As you
know, gold can be beaten out so finely that 280,000 leaves
will be required to make a thickness of 1 in. Gold leaf

is obtained in
books each about
3 in. square, con-
taining 25 leaves
of gold, which can
be transferred to
a washleather pad
(Fig. 1) by means
of a little flat brush
known as a tip (Fig. 2), which is passed once or twice
over the hair of the head to give it the mere suspicion of
greasiness. The gold leaf as it lies on the washleather
pad is cut into strips, etc., by means of a long
flexible blunt-edged knife (Fig. 3), and is transferred
fiom the cushion by means of the tip to the woik,
which previously has been specially prepared. Sur-
faces to be gilded need to be coated with oil paint,

190

Fig. 1.— Cushion for Holding Gold Leaf

Gilding with Gold Leaf and Gold Paint

preferably of a yellow colour, or with size containing
chrome pigment, the object being to build up a solid
surface and to stop the suction of the material. Before
laying the gold leaf the work must be given a coat of
gilder's oil gold size, which must be bought ready made.
Every part of the surface must be gone over sparingly

and evenly, but the
gold leaf should not
be applied until after
several hours have
elapsed, the actual
period varying with
the temperature and
with the grade of size
used. Probably at the
end of twelve hours,
if not long before, the
size will be ready to
receive the gold leaf.
To test it, touch it with the ball of the thumb.
If it prove to be " tacky," the thumb is not
wetted by the size, and the surface is not dis-
turbed by the thumb, you may regard the size as
being in the correct condition, and the gold may be
laid upon it, each strip slightly overlapping the earlier
one, and the whole /-m;-
being afterwards
lightly gone over

Fi^- ?.— Tip for Lifting and Applying
Gold Leaf

Fig. 3.— Knife for Cutting Gold Leaf

with a pad of cotton wool covered with soft clean muslin.
Afterwards brush over with a soft brush and a bright
appearance will indicate a satisfactory job ; but if the

191

Every Boy His Own Mechanic

gold is lustreless and smeary the size was not tacky enough
and the job must be left for many hours longer, and, if
necessary, coated again with size, left for a period of time
as to which you will be guided by your first experience,
and the whole given a second coat of gold leaf. Two-
coat work has a more solid appearance than the one-coat,
of course.

The above process has its many difficulties. Gold
leaf is most difficult stuff to handle,, the slightest breath of
air disturbs it, and it is easily damaged in course of laying.
It is much easier to use gold transfer paper, which is sold
in the form of books of beeswaxed paper, to which the
gold leaf is adhering. The work is prepared by painting
or sizing and finally gold-sizing exactly as before, and the
transfer paper is applied face downwards and rubbed on
the back to cause the gold to leave the waxed paper
and cling to the sized surface.

Probably you will come to the conclusion that if you
want a gilt effect on woodwork, plaster, etc., you will
use the far cheaper and easier gold paint, which is simply a
finely powdered metallic alloy of golden colour mixed with
a suitable liquid. The bought gold paints used to be far
superior to anything that could be mixed up at home.
The difficulty was the liquid or medium. I used to ex-
periment with thin french polish, but the result was very
" brassy." All sorts of things have been tried, but the
vehicle or medium used nowadays and certainly the most
successful of all is celluloid varnish made by dissolving
I oz. of finely shredded transparent celluloid in 9 or 10 oz.
of amyl acetate, a liquid you will recognise by its " pear-
drop " odour; indeed, it is used as jargonelle-pear essence.

192

Gilding with Gold Leaf and Gold Paint

Ask for the best "French flake gold bronze powder."
You will find | oz. of it go a long way, and you will simply
mix it with the celluloid varnish as you need the paint,
because the varnish (highly inflammable) is useful for lots
of other things. Just as in gold leaf gilding, the effect of
gold paint is very much enhanced if the work has been
properly prepared beforehand. A dark ground will rob
the paint of its solid appearance, and if there is much
gold painting to be done, say a set of picture frames, it
would be best to get from a coach painter a small quantity
of a varnish paint made up with orange or middle chrome
pigment. Coach painters are clever people at mixing
paint and will be able to give you just what you want,
but if you have any difficulty, get from a decorator's
supply store a small tube of orange or middle chrome paste
paint, and mix this to a suitable consistency with a medium
or vehicle consisting of boiled linseed oil 4 parts, best
oak varnish 2 parts, and genuine turpentine 1 part. Apply
this to the glass-papered surface, and allow at least a
day for drying, Rub out brush marks with worn glass-
paper used lightly, and if you think it necessary give it
another coat of paint, allowing the same time to dry,
and smoothmg out any brush marks as before. Dust
the work, and then apply the gold paint with a camel-
hair or sable brush.

Silver and aluminium bronze powders for making
silver and aluminium paints cap also be bought.

193

MAKING MORTISE-AND-TENON JOINTS

An "Open" Mortise. — I cannot hope to show you in
this chapter how to make all the various kinds of mortise-
and-tenon joints. There are actually scores of varieties,
and I can afford space to deal with only two or three of
the commonest but, at the same time, most important
kinds. A mortise-and-tenon joint connecting the ends of
two pieces of framework {see Fig. 1) is known as an open
joint, the end grain of both of the pieces being visible, as
shown. The mortise itself is open, and does not con-
stitute a box, as it does in the closed type, which I shall
take as my second example.

I must assume that you have planed up the work
parallel and trued the ends. With a square carry round
on all four sides of the stuff and on both members of the
joint the shoulder lines which will indicate in one case
the depth of the mortise and in the other case the length
of the tenon. Now, with a gauge set to one-third the
thickness of the stuff, mark the two sides and ends, as
shown in Fig. 2, and before proceeding further, mark with
a pencil cross those parts that are to be removed — the
middle part of the mortise piece, the two outer parts of
the tenon piece. I attach great importance to indicating
the waste in this way. May I confess that I have attached
that importance ever since the day when I spoiled a table

194

Making Mortise-and-Tenon Joints

framework by thoughtlessly cutting through a tenon
instead of through the waste at the side of it. It taught
me a lesson which I should like you to learn at less
expense than my mistake meant to me.

First let us make the mortise, which is in this case

Fig. 1.— '

Open'' Mortise-and-tenoii
Joint

Fig. 4. — Second Position
of Chisel in Removing
Waste.

Fig. 5.— EflFect of Taking Chips
from Both Sides

Fig 3. — Starting to
Remove Waste of
Mortise

merely an open slot. Place the work upright in the bench
vice, and with extreme care run in a fine saw on the waste
side — the inside — of the setting out lines. We are going
to remove the piece of waste with a chisel. Placing it in
the position shown in Fig. 3, but not quite as far back as
the shoulder line, drive it in with a hammer or mallet

195

Every Boy His Own Mechanic

for I in. or so. Then withdraw it, and re-insert in such
a way as to cut a V-shaped chip from the waste. Drive
in the chisel still farther vertically, and take another
slanting cut so as to remove more waste. Repeat until
a V-shaped slot half the depth of the stuff has been formed.
Turn the piece over and do the same from the other edge,
thus detaching a piece of waste of the shape shown in
the cut-away view, Fig. 5. Next, with a chisel in perfectly
keen condition, pare the bottom of the slot right up to
the shoulder line.

The above is the slowest method of doing the work.
It is much quicker to use a brace and twist-bit, running
the bit into the work close to the shoulder line as illus-
trated in Fig. 6, but note that the bit must be slightly less
in diameter than the width of the mortise, and the slot
must be finished with a keen chisel as before.

As it is not every boy mechanic who possesses a mortise
gauge, I have described in the foregoing a method of
setting out a joint with an ordinary marking gauge,
which gauge, by the way, must be used from the same
face of the work all the time; otherwise, if the wood
varies in thickness the tenon will not fit the mortise.
The use of a mortise gauge makes for better and more
accurate results and it is usual to set its two marking
points to the width of the chisel that will be used for
cutting the mortise, particularly in making a closed
mortise, where, of course the saw cannot be used. Fig. 7
shows how the mortise gauge is set to the width of the
chisel, the gauge being altered by turning the thumb-
screw shown at the end of the stem. One of the two points
is fixed, and the other is controlled by the thumb-sere r

196

Making Mortise-and-Tenon Joints

but the screw in the square part (the stock) must first be
loosened. The stock is then slid into its proper position,
according to the dimensions of the stuff, and secured
there by tightening its screw.

Fig. 6. — Removing Mortise Waste
with Twist-bit

Fig. 7. — Setting Points of Mortise
Gauge to width of Chisel

Figs. 8 and 9.— Home-
made Mortise Gauge

A substitute for the mortise gauge is the little home-
made device shown in Figs. 8 and 9, which scarcely needs
description. It costs nothing except the trouble of making,
but the two sharp nails constitute fixed points, and you
will need to make a separate gauge for every different
thickness of stuff worked or width of mortise required.

Next we will proceed with the shaping of the tenon on
the end of the other piece of stuff. It has already been
set out with marking gauge, mortise gauge, or a home-
made scratch gauge as above described. Fix the piece in

197

Every Boy His Own Mechanic

the bench screw, and saw down on or slightly outside
the lines drawn on the end grain, and then cut on the
shoulder lines from opposite faces so as to detach two
pieces of waste.

A "Closed" Mortise. — The closed form of mortise-
and-tenon joint is shown in Fig. 10. Some readers might
think that the name ought more properly to be applied to
a joint in which the tenon does not go right through the
mortised member, but a joint of that particular kind
would be known as a shouldered, stump or stub mortise-
and-tenon.

The setting out of the open joint is practically as

Fig. 10.—" Closed " Mortise-

and-Tenon Joint Fig. 10a, — Model Joint Set Out

before described, and in the case of the tenon the setting
out and cutting are exactly so. The extent of the mortise
will be set out on all four sides of the work, but its actua
opening will be set out on the two edges only. Note that
the gauge must be used from the same face of the work
all the time. Fig. 10a shows a model joint set out.

A quick method of cutting the mortise is to make
with brace and twist-bit a series of holes close together or
slightly overlapping, so removing the bulk of the waste
and leaving the mortise to be finally trimmed by means
of a keen chisel ; but this is not the time-honoured method
employed in general joinery work, and it needs to be
pointed out that unless the boring be done absolutely at

iq8

Making Mortise-and-Tenon Joints

right angles to the edge there is a grave risk of spoiling

the job. The usual method, therefore, is to cut out the

mortise by means of a series of chips, the work being held

down firmly on the bench, for which purpose the work is

placed on the edge of the bench alongside the bench vice c

(Fig. 11), and held tightly down by means of an L-shaped

piece A, which presses upon a packing piece b, and is

itself held tightly by the vice. By adopting some such

arrangement as this both hands are free to hold the tools

and there is no risk of a sudden movement of the work.

The cutting out of

^^ j — ..•-'

the mortise is started / /" -"---. y' ..•-

by making a little
V-shaped notch with
a chisel right in the
middle of the waste.
(Note the exact posi-
tion of the chisel in
Fig. llA.) This is
enlarged at every
chip {see Figs. 12 and
13, which, of course
are cut - away views)
until the mortise has
been cut out clean and
square. The whole of the cutting cannot be con-
veniently done from one edge, so when half the
waste has been removed it is well to turn the work
over and repeat the process from the other. It will
be found in practice that a series of wedge-shaped
chips are formed, and these will be required to be levered

199

Fig. 11. — Cutting Closed Mortise
in Wood held down by t -piece

Every Boy His Own Mechanic

out. The proper tool for this work is a mortise chisel,
which is a thicker, stronger tool than the ordinary firmer
chisel. Take particular note that the ends of the mortise
are finished with the bevel of the chisel directed toward
the mortise so as to produce a clean vertical cut, as in
Fig. 14.

The above instructions will answer quite well, if in-

Fig. Ua. — Starting to
Remove Waste of
Mortise

Fig. 13.— Taking the

Next Cut

Fig. 12.— Method of
Removing Chips
from Mortise

Fig. 14. — Finishing
Mortise Vertically

terpreted with reasonable intelligence, for the making of
shouldered tenons {see Fig. 15) ; generally the mortise
will go about half-way through the work, and the length
of the tenon will correspond, but make the tenon just a
shade shorter than the hole is deep.

Wedging Joints. — Very frequently mortises are
slightly under-cut, so as to produce a dovetail effect, and

zoo

Making Mortise-and-Tenon Joints

the ends of the tenon are sawn down with the grain, and
wedges are inserted, as shown in Figs. 16 and 17. The

tig. 15. — Shouldered Tenon

Fig. 15a. — Wedged Tenon

combined thickness of these wedges must not exceed the

amount by which the mortise has been under-cut. Then

on inserting just the points of the wedges in the saw-cuts

the two parts of the joint

can be driven together

forcibly, with the result <

that the wedges will L..

spread the tenon in the

mortise and form a

dovetail. This is known

as "fox- wedging," but

the usual method of

wedging the ordinary

" closed " joint in which

the mortise goes right

through the work is to

drive in wedges from

Figs. 16 end 17.—
Tenon

Fig. 17
Fox-wedded

20I

Every Boy His Own Mechanic

Fig. 18. — Marking Tenon for
Draw-boring

the opposite side over and under the tenon^ the
wedges being as wide as the tenon is thick, as
shown in Fig. 15a.

Pinning Joints. — When wedging is not adopted, the

ordinary way of securing a
mortise-and- tenon joint is
with a wooden pin, and there
is a particular method of
inserting this to ensure that
the tenon is drawn well
home. It is known as
" draw-boring." The joint
having been made and
fitted, it is taken apart
and a twist-bit is passed
right through the cheeks
of the mortise ; the tenon
is re-inserted, the bit
replaced, and its point
allowed to make a mark
on the tenon, as suggested
in the cut - away view
(Fig. 18). Next the tenon
is removed, and the twist-
bit placed very slightly
nearer the shoulder, as in
Fig. 19, and a hole bored
through. When the joint

Fig. 19. —The Boring Bit Placed
Slightly Nearer Shoulder

Fig. 20. — Draw-bore Holes
not in Line

Fig. 21.— Pin for Joint

is again put together there will be a hole through the
two cheeks of the mortise and also through the tenon,
but it will not be a straight one {see Fig. 20). By

202

Making Mortise-and-Tenon Joints

driving in an oak pin (Fig. 21) from one side of the
mortise, the tenon will be tightly cramped up, but it
may first be necessary to draw the joint together
with a steel pin, afterwards replacing it with the
wooden one.

If you try this method, do not forget the following pre-
cautions : Don't overdo it by making the distance by
which the hole in the tenon is out of alignment too great,
or, instead of cramping up the joint, the forcible driving
home of the pin may split a piece from the tenon, or at
any rate spoil the pin. Secondly, see that when you shift
the bit for boring you place it nearer the shoulder and
not farther away from it, as has been done many hundreds
of times.

203

BUILDING A CARDBOARD MODEL L. & S.W.R.
EXPRESS LOCOMOTIVE

By Henry Greenly

Before the boy mechanic essays to build a model loco-
motive he should know something of the various types
from which he may choose. All the larger railway com-
panies possess characteristic designs of locomotives each
suited to the work allotted to it. They are classified by
the wheel arrangement, as indicated in the diagram
(Fig. 1), the numeral system being adopted to distinguish

o Q^ ooQOO

2-4.-0 4^ - e - o

0-6-0 q--6-2,

O- 8-0 2.6.0

ooGQo noOQ

Or - ^- Z. 4-. 4.-0

OQQQQ OQQQO

2,-g-O 2-6-2

Fig. 1. — Diagram Explaining Wheel Classification of Locomotives

204

205

Every Boy His Own Mechanic

the types. The most common for express trains is the
four-coupled bogie engine termed the " 4 — 4 — 0 " type
and for the subject matter of this chapter a model of one
of this class has been chosen. A " 4 — 4 — 0 " arrange-
ment is included in the diagram (Fig. 1) and a picture

of a model loco-
_j motive of this

identical class is
presented in one
of the photo-
graphic plates.

In model work
there are several
standard gauges.
Model locomo-
tives in the
smaller gauges
are, of course,
the least expen-
sive, and require
simpler tools to
make. The gauges
(always measured
between the rails)
vary between No.
0 (IJ in.) and 15
in. for garden and
estate models,
the four smaller
sizes having the
designating
2o6

Building a Model Locomotive

numeral (Nos. 0, 1, 2 or 3 as the case may be) in addition
to the dimensions. The following table will be helpful in
understanding and in choosing among model locomotives
in all the more common dimensions.

TABLE OF GAUGES AND SCALES FOR MODEL LOCOMOTIVES

No.

Gauge
0 m in.)

No. 1 (l|in.)

No. 2 (2 in.)

No. 3 (2i in )

3J in. gauge
3i in. gauge
4| in gauge

() in. gauge
7i in. gauge
9 J in gauge
15 in. gauge

Scale
7 mm. to 1 ft.
(about 5'f tl' full size)

10 mm. to 1 ft.
(about jSjlh full size)

1 U mm. to 1 ft.
or ^'^ in. to 1 ft.
(about rtVth full size)

13 mm. to 1 ft.
i in. to 1 ft.
(^th full size)

Uin. to 1ft.
f in. to 1 ft.

1 in to 1 ft.

IJin. to 1 ft.
liiii. to 1 ft.

2 in. to 1 ft.

3 in. to 1 ft.

Eminently suitable for indoor
railways where space is limited
or where a big railway scheme
is intended. Locomotives can
be driven by clockwork or elec-
tricity. A few steam models
have been made for this gauge.

The best gauge lor electrical,
steam and clockwork loco-
motives for indoor model rail-
ways.

The largest size advisable for
an indoor railway. Most suit-
able small size for steam and
electric locomotives.
The smallest outdoor size ad-
visable

This gauge is not being de-
veloped very much for indoor
lines or for clockwork loco-
motives.

The amateur steam locomotive
builders' favourite gauge, es-
pecially where the railway
portion of the equipment is of
secondary importance.
The best small outdoor size.

These sizes are suited to exhi-
bition models, made by skilled
mechanics

F'or gaiden and estate model
railways carrying passengers
and goods.

A full engineering equipment
is required to produce models
in these scales.

207

Every Boy His Own Mechanic

The foregoing table is not only useful in preventing an
inexperienced worker from making a locomotive to some
odd scale and gauge, but will enable him to fix upon a size
to which he can construct locomotives of progressive
degrees of completeness and workmanship. For instance,
should the No. 3 (2| in.) gauge be decided upon, the first
locomotive may be a simple shunting engine running on
four or six wheels. When successfully finished and more

Fig. 4. — Wooden
Wheel (A) and Card-
board Wheel (b)

Driving and Coupled Wheel,
with Boss

skill and further tools have been acquired, an express
engine of more complicated character may be attempted,
and both of the engines will be available on the same
track. Once the locomotive hobby is started there is
little or no finality in it, and therefore the basis of the
work — namely the size of the line of railwaj^ — needs to
be earnestly considered at the outset.

For the average novice the indoor railway is usually
the least difficult proposition, and while the smallest
gauge (No. 0) may be adopted, No. 1 (If in.) gauge will be
found to provide a size which is not expensive in the

208

MODEL LOCOMOTIVE, STATION AND
SIGNALS

Model L, & S.W. Express Locomotive

Model Railway Station

Model Locomotive, Rolling Stock, Signals, etc.

Building a Model Locomotive

Gauge

Fiji. 6. — Front Elevation of Model
Locomotive

or electric locomotive,
in which case tin plate,
strip metal, and solder
would take the place of
cardboard, wood strips,
and glue.

Figs. 2, 3, 6, 7, and
8 show dimensioned the
leading features of a
No. 1 (If in.) gauge
model L. &S.W. R.
" 4 — 4 — 0 " type express
locomotive with a
double - bogie tender.
The engine is extremely
o

matter of materials and
not too small to be diffi-
cult to construct. We
will therefore consider
first the building of a
model cardboard loco-
motive. Such a model
may afterwards be
altered to run by clock-
work or electricity if a
suitable motor is ob-
tained.

The drawings are
sufficiently correct in
detail to be used for
an all-metal clockwork

Fig
209

. 7. — Front Elevation of Model
Tender

Every Boy His Own Mechanic

.f^

■*l

Kw~^

^l?i

-1

—

fVJ

' f

•

^^'*n

■9/

_IM

"n:

) ■

=r^.

_-_=J

U-

= ^

2IO

neat and simple in
outline. There are no
outside cylinders or
valve motions to
model, and supplied
with a clockwork
motor a very success-
ful locomotive should
result. Only two dia-
meters of wheels are
employed on the whole
machine, which fact
also simplifies the
work.

Wheels. — For a
cardboard model the
first and most import-
ant consideration is
the making of the
wheels. Suitable metal
wheels with proper
spokes and coupling-
rod boxes may, in
normal times, be ob-
tained, but, failing
these, there are two
good methods of mak-
ing wheels. They may
be turned in hard wood
as at A (Fig. 4) ; box
or beech i wood will

Building a Model Locomotive

give the best results. Or the wheels may be built
up out of discs of cardboard glued together as shown in
the section b (Fig. 4). In either arrangement the
spokes, of course, will be absent. In the case of card-
board wheels, to provide for the flange the disc at the back
should be nearly J in. bigger in diameter than the diameter
of the wheel on the tread. For the driving and coupled
wheels the pear-shaped bosses which embrace the coupling-
rod pins will require to be added ; these may be cut out
and applied to the face of the wheel. Even with the
wooden wheels this will have to be done {see Fig. 5), as
it is impossible to turn bosses of this shape.

Main Frames. — The main frames are shown in Figs. 8
and 8a, those of the bogies being separate structures.
To reduce work, the engine and tender bogies have been
made of similar construction, the wheel-base (distance
between the wheels, centre to centre) being smaller in
the case of the tender bogies ; the long slot for the bogie
pin and the dummy equalising spring gear are omitted.
The side frames of the engine are rather complicated by
the fact that at the front bogie the underside of the foot-
plate is quite clear except for the edging. This is to give
room for the bogie to rotate and swing.

The footplates and panels should be made of stout
Bristol board or other close-grained white card. The
only slots in the footplates are those required to clear the
coupled wheels {see h. Fig. 8). Some strip wood, -^' in.
by \ in. section, is required for the edging (e d), and
\ in. by -^ in. stuff for the crosspieces (c p) and other
stiffening blocks. The outlines of all these blocks and
all centre lines should be drawn on the pieces of card used

211

O "

a :

fl5 -^

o 15

U .>

Qi)

•a

pii

c«

=«

312

Building a Model Locomotive

for the frames and footplating. Between the crosspieces
c p and c p, the strip work shown at m p and c b (Figs. 8
and 8a) may be added to stiffen up the footplate and also

to represent the motion

,C(> ^ ^' ■ '

J-

\ Axle

Sidt ^ramts
foot bio re

'so

WheeJs

plate and slide bars of
the real engine.

Coupled Wheels,
Bogie, etc. — The detail
drawings of main axle-
boxes (Figs. 9 and 10)
show the arrangement of
the coupled wheels in the
frame. By using slotted
axleboxes instead of plain
drilled holes it is possible to fit up the wheels on their
axles and then put them into place complete, securing
them by a " keep " plate (strip wood, metal or card), as
shown at k.

Fig. 10 is a view of the back of the engine from the

Fig. 9. — Section showing Details of
Axleboxes, Frames, etc.

(eac/f)

£0 ^ Foot p/oTej Ax/QboKCs

Fig. 10. — View of Rear End of Engine from
Underside, showing Axleboxes, etc.

underside. Fig. 9 is a sectional view of the frames and
front main axlebox, showing how the side frames are

213

Every Boy His Own Mechanic

continued below the footplate level to a point which just
overlaps the frame of the leading bogie. The latter
structure is illustrated by Fig. 11. The framing consists
of three pieces of card secured together by angle-blocks
in the inside top corners. The spring work (equalisers,
etc.) is, in this case, mere ornament applied to the out-
side. To obtain the relief, the parts may be built up in
layers ; for instance, three layers would make the equalisers
and one and two the springs underneath. For the axle-

Slot -for bm

Oncjfe ' ^

blocKs

equi/iyrs

Fig. 11. — Details of Leading Bogie

'ax^eboKes

boxes wood blocks are suggested, but, of course, four or
more layers of card may be employed.

Boiler. — The boiler barrel may be made out of a
piece of flat card over a good round postal tube, curtain-
pole or anything similar. The diameter of the boiler
barrel is given as 2^ in., so that the tube bar or pole
chosen should measure as nearly as possible 2| in. diameter
outside. If a postal tube is employed it may, of course,
be cut to length and left inside the boiler barrel to stiffen
the whole structure. The front end of the barrel has an
additional wrapper strip w (Fig. 8a) the width of the
smokebox glued on to it. The firebox end is opened out

314

Building a Model Locomotive

as indicated ; the rear end of the firebox sides f s being
retained to the shape required by a flat piece of wood
about J in. thick, cut out to fit inside. This piece of
wood F E (firebox end) should project slightly, and the
outer edge should be rounded as shown in Fig. 8a.

Funnel and Dome. — The funnel and dome {see
Fig. 12) are best turned out of beech or box wood to the
shape as shown, and if no lathe is available the builder
must rely on the help of a pattern-maker or wood turner.
If turned in box or other similar close-grained Avood the

Hofef>,
Fig. 12. — Funnel Turned from Wood

tvhirenint)
Stucco

Fig. 13. — Funnel Shaped
from Composition

saddling of the underside of these mountings may be
done with the file, the base curves at the sides being
modified with the same tool. The other alternative is to
turn them straight down with a dowel pin out of the solid,
and then to form the base curves with a stucco made of
whitening and hot glue {see Fig. 13). When dry, this
mixture, if there is enough whitening in it, can be carved
with a penknife or filed to shape. The safety valves on
the top of the dome should be of bright brass, also the
whistle. Oddments may be worked up into these, or
cheap dummy fittings may perhaps be bought. In
referring to scrap it is always advisable for the amateur

Every Boy His Own Mechanic

model maker to collect odd fittmgs, old clocks, instru-
ments, bits of other small machinery, etc., for future use.
Tender. — The tender is a simple box structure,
which is strong in itself, the side framing b s F (Fig. 3
and 14) underneath being necessary only to overlap the
bogie frames and give the undergear a solid appearance.
The bogie frames are shown in Fig. 15, and their attach-
ment is indicated in the sectional drawing (Fig. 3). A
plain pivot hole only (instead of the slot necessary in an

Fig, 14. — Details of Model Tender

engine bogie) is required in the case of a double-bogie
vehicle. The pivot is a screw which engages in a block
of wood inside the tender body. In building up the
body, angle blocks of wood may be freely used to unite
the cardboard "plates" forming the sides, ends, etc
The coal space has a sloping bottom, and the coal rail
may be built up out of wire or a strip of card may be glued
on the top edge, and the rails represented by drawing
wide black lines on the card to represent the spaces
between the rails.

Completion of Model.^ — When complete any rough
edges on the joints should be trimmed up with glasspaper

2l6

Building a Model Locomotive

and the whole locomotive and tender coated with size.
This is a necessary preliminary to the coating of paper
with oil paint, and any loose parts such as bogies should
be removed.

The coupling-rods may be made of wood or metal
and " screwed " into the wheels ; the screws are secured
by seccotine or a shellac cement. The coupling-rods on
each side of the locomotive are arranged at 90 deg. to
each other, not opposite.

M>/e -for^'n

Qn^le biociYs \.J^'^ ^ fran-t
Fig. 15. — Bogie Frames of Tender

The hand-rails (Fig. 16) should be made of stiff wire,
the rail along the boiler being fitted into standards made
of split pins. The boiler bands should be strips of card
carefully cut out with a sharp knife and glued on to the
boiler, the joints being on the underside. Buffers may
be made of wood, small drawing pins, polished bright,
forming the heads. The hooks are best made of two or
three thicknesses of strong card glued together.

One or two elementary hints may be given for the
benefit of readers who have not attempted such an am-
bitious model before. The parts should be drawn out
on the card before cutting them up ; care being exercised
to see that the setting out is correct. This will ensure an

217

Every Boy His Own Mechanic

accurate result and good fitting of the parts. The glue
should not be too thin or too lavishly used. One pro-
fessional expert in cardboard modelling known to the
writer strongly advocated gum arable as an adhesive,
saying that with this substance and by building up layer
on layer, models would last at least a hundred years.
(J pi it bin The gum arabic needs to be dissolved

in water. Except where wood parts

are employed good gum may be used

^Handrail ^'^ ^^ P^^^^ ^^ g^^^-

Fig. 16.— Details of Some of the letter references in the

Handrail illustrations given in this chapter have

already been explained. The following is a complete
list :—

Locomotive : a b, axleboxes ; b b, boiler barrel ;
K, keep for axleboxes ; w, wrapper for smokebox ; s b,
smokebox door ; f r, smokebox front plate ; w T c,
water-tube cover ; c p R, coupling-rods ; c t, cab top ;
w I, whistle ; c H, chimney ; d, dome ; g i, guard irons ;
c E, corner frame edging ; e d, edging of frames ; c c,
cylinder cover piece ; b, buffers ; b p, buffer planks ;
c p, cross pieces ; b s, back step (and front step of tender) ;
M p, motion plate ; f s, firebox sides ; f e, firebox end.

Tender : b s f, bogie stop frames ; c r, coal rails ;
T p, tank top ; h r, hand rails ; t t, tender tanks ; t b,
tool boxes ; r t, tank filler ; b p, buffer planks.

218

TURNING WOOD IN THE LATHE

By A. MiLLWARD

The Lathe. — A boy who owns (or can get the use of)
a lathe, however simple its form, will find it invaluable
not only for making any number of useful things, but also
as a great help in many other hobbies. Any object
having a circular form can be readily and truly shaped in
a lathe, which comprises essentially a pair of "centres"
between which the work is revolved against the action of
a cutting tool. In order to make the instructions which
follow more easily understood it is proposed to give first
a brief description of the component parts of a lathe with
their proper names.

In Fig. 1 is shown a front view of a simple form of
lathe, in which a is a foundation plate or bed carried on
a bench or legs a\ On the bed a is fixed the headstock h,
which carries a revolving spindle or mandrel c, which is
rotated by pulleys d fixed thereon. The pulleys d are
driven by a belt e passing over one of the pulleys d and
over another pulley of a series of pulleys/, which are driven
or rotated by a treadle g through the medium of a crank
pin h on the pulley and a connecting rod or pitman ^.
The variation in the sizes of the pulleys d and/ is to pro-
vide a simple form of gear for varying the speed of the
mandrel. It will be apparent that if the belt c is placed
on the first or outer pulleys (that is, on the smallest one

Every Boy His Own Mechanic

of the pulleys d and on the largest one of the pulleys /),
then the mandrel c will be rotated at a greater speed
than would be the case were the belt placed as shown in
the illustration, but the speed of treadling would remain
constant.

On the opposite end of the bed a, is arranged the loose
headstock, tailstock, or back poppet k, which is free to

Fig. 1. — Diagram of Simple Lathe with Parts Lettered for Reference

move on the bed a until clamped in position. The back
poppet k carries a spindle I which, on turning the wheel l^,
is moved through it by a screw. A tool rest m is clamped
to the bed in any desired position. The mandrel c and
the spindle I are each provided with centres n, which
must be exactly opposite one another in order to produce
perfectly round work. Fig. 1 must be looked upon not

220

Turning Wood in the Lathe

as being the drawing of any particular form of lathe,
but merely typical of a simple form, as almost any lathe,
however complicated, will comprise the above described
essential parts.

Figs. 2 and 3. — Wood-turning Gouge

Tools. — With regard to the tools required for wood
turning it will be sufficient to start with a wood-turning
gouge {see Figs. 2 and 3, which are plan and side views

•^si

cEir:

Fig8. 4 and 5. — Wood-turning Chisel

respectively) and a chisel {see Figs. 4 and 5, which are
also plan and side views). It will be seen that the chisel,
unlike an ordinary wood chisel, is bevelled or sharpened

Fig. 6. — Tool Handle to be Turned in Wood

from both sides, and its edge is inclined instead of being
square with its sides.

Making: a Tool Handle. — ^As a first attempt at wood-
turning it is proposed to make a tool handle, as shown by

22J

Every Boy His Own Mechanic

Fig. 6. Get a piece of square wood (the most suitable
will be beech, which is inexpensive and fairly hard and
close-grained) an inch or two longer than the handle when
finished is required to be, and of a thickness slightly

Fig. 7. — Square Piece of Wood for Tool Handle

greater than the largest diameter of the finished handle.
Square the ends and mark diagonal lines a b from each
corner, as shown on Fig. 7- At the point where the two
lines cross each other — which will be the axial centre of
the wood — make holes with a centre punch. Now chisel
or plane away the corners c of the wood shown in dotted
lines on Fig. 8, and make a saw cut d along one of the

^.f-^

\ 1 /

Fig. 8. — Wood for Turning Tool Handle prepared for the Prong Chuck

diagonal lines on the end to take a " prong " or " horn "
chuck {see Figs. 9 and 10) which is inserted in the nose of
the mandrel c {see Fig. 1) in place of the plain centre n.
The prong or horn chuck, of which a side view is shown

222

Turning Wood in the Lathe

on Fig. 9 and an end view on Fig. 10, is for the purpose
of causing the wood to turn with the mandrel whilst
being cut.

Be careful to see that the centre prong of the chuck
enters the centre hole of the saw cut. Fix the chuck in
the wood by giving the end of the wood or the end of the
chuck a smart blow with a hammer. Adjust the back
poppet k {see Fig. 1), and then screw in the spindle I so
that its centre n enters the hole at the other end of the
wood, first putting a little grease, oil or black lead in the
centre hole.

Fig. 9. Fig. 10.

Figs. 9 and 10. — Two Views of Prong Chuck

It is advisable to screw up the spindle I fairly tightly
at first; any binding resulting therefrom will disappear
after a few revolutions. Now adjust the tool rest m
(Fig. 1) until its top edge is below the centre of the work,
and so that the wood when revolving is just clear of the
front edge of the rest. Take the gouge and work the
treadle to cause the top of the work to turn towards you
at a faii'ly high speed. Rest the rounded side of the
gouge on the top side of the rest m with the hands well
down so that the cutting edge will be higher than the
hands. It is essential to hold the gouge very firmly, the
right hand grasping the handle with thumb uppermost
and the left hand grasping the tool with the knuckles
uppermost a few inches from the rest m. Now press the

223

Every Boy His Own Mechanic

tool forwards towards the work until it begins to cut, and
then move it along until a few inches are reduced to the
same diameter. Then press the tool farther, and move
it back again until the beginning of the cut is reached,
and so on until the desired diameter is obtained, adjusting
the height of the tool rest as required.

It is always advisable to turn the larger diameters
first before turning the smaller ones. In the present case
the main portions of the handle will first be turned, then
the ends reduced ; the one end a {see Fig. 11) nearest the
fixed centre should be turned down to fit into a short

Fig. 11. — Turning the Tool Handle

length of brass tube to form a ferrule so as to prevent the
handle splitting when the tool is driven into it.

A pair of outside callipers (Fig. 12) will be required to
gauge the diameter of the work, and since it will be neces-
sary hereafter to have means for measuring internal
diameters such as holes, hollows or insides of boxes, etc.,
it will be as well to get a pair of inside callipers also (see
Fig. 13).

To use callipers, first set them to the desired diameter
by placing the end of one of the legs against the end of a
rule, and extending them until the end of the other leg
coincides with the required measurement on the rule.
Always bring the work to rest in the lathe before attempting
to calliper or gauge it.

If the cut is not satisfactory or the wood is torn rather

2?i\

Turning Wood in the Lathe

than cut the fault will be found to be : (1) Speed not
high enough. (2) Tool not sharp enough. (3) Wrong
position of the cutting edge. The third fault is the
most common. The remedies for the first two faults are
obvious, while the third can usually be put right by
dropping the hands a little so as to raise the cutting
edge of the tool ; but see that the tool rest is at the
correct height.

Fig. 12. — Outside Calipers

Fig. 13. — Inside Calipers

After the whole surface has been turned or "roughed
out " with the gouge to the desired size, it will be found
that the surface consists of a series of ridges instead of
being smooth. To obtain a smooth surface, the chisel
must be used. This tool, like all cutting tools, must be
kept absolutely sharp, and a good oilstone is therefore a
very necessary item.

To use a chisel properly is very much more difficult
than the use of the gouge. It must be so held in relation
p 225

Every Boy His Own Mechanic

to the work that only the middle part of the edge does the
cutting. It must not be used, as is so often the case with
amateurs, as a scraping tool. Fig. 14 shows the proper
way of using the chisel, a being the cutting part of the
edge, the highest point or edge a^ being above and out of
contact with the work x, whilst the lower point a^ is
below and also out of contact with the work. In such a
position a smooth, even surface will be produced as the
tool is moved along the rest m from right to left, but con-
siderable practice

will be required to
prevent the edges
a^ or a* digging
into the work.

An easier way
of obtaining a
smooth surface is
to use an ordinary

Fig. H.-Using Chkel In Wood Turning carpenter's chiscl

sharpened to a truly square edge on one side only. The
bevel of the chisel should be underneath and the top
side of the chisel should be in line with the centre of
the work. As a chisel so held scrapes rather than cuts,
it will be necessary to sharpen it continually.

When the surface has been gone over and reduced to
the desired size with the chisel it should be perfectly
smooth, but this is seldom obtained at a first attempt.
To make it quite smooth, take a piece of fine glasspaper
and press it lightly on the surface backwards and forwards
whilst revolving the work at a high speed. To polish
the work, press against it whilst it revolves in the lathe

226

Turning Wood in the Lathe

a rag dipped in linseed oil or smeared with beeswax and
turpentine.

The end a^ (Fig. 11) of the handle must now be cut
off. To cut off a piece of work in the lathe a parting

Fig. 15.— Cutting-off Tool

tool, illustrated by Fig. 15, is employed, and must be
held at right angles to the axis of the work and advanced
into the work in that position without moving it to the
right or left. It is not advisable to cut right through
with the parting tool owing to the liability of the work to
break and perhaps be spoilt ; it is better to turn down
as much as possible without breaking, remove the work
from the lathe, and to cut off with a fine saw.

In the present case it will not be necessary to use a
parting tool, as the end to be cut off will already be turned
down to a fine neck, which can be easily sawn through,
and the saw marks removed by means of glasspaper.

Having turned the
handle satisfactorily it
will be an easy matter
to use the knowledge
so gained in doing

... , Fig. 16.— Another Tool Handle

more ambitious work.

Fig. 16 shows a slightly different form of handle,
Fig. 17 a bail or spindle, Fig. 18 a chair or stool leg, and
Fig. 19 a drawer knob or handle, all of which can be turned
after some practice.

Screw Chuck. — It is not always convenient or even

227

Every Boy His Own Mechanic

possible to turn some work between centres ; take, for
instance, a powder box (shown in section in Fig. 20) or
an egg-cup (see Fig. 21) or other articles requiring to be
hollowed out. In such cases the block of wood must be
held on to the mandrel by some other means than the
prong chuck already described.

Fig. 22 shows a screw chuck which will be found very
useful ; this, as shown, comprises a shank a fitting into
the end of the mandrel (or in some cases it may be pro-
vided with a socket to screw on to the mandrel nose), a
plate b and a tapered wood screw c projecting centrally

Fig. 17.— Bail or Spindle d

^nOOdir:^^

Fig. 19. — Drawer
Fig. 18. — Leg of Chair or Stool Knob or Handle

from the face of the plate b. In use, a centre hole is first
made in the wood, and then the wood is screwed on to the
screw c until its back surface (which should be first planed
true) butts against the plate b. The taper screw chuck
can be employed only when the diameter of the work is
fairly small and is not of great length ; if it is required to
turn a disc or a wheel or a circular picture frame {see
Figs. 23 and 24, which are a front view and side section
respectively) it is better to screw the wood either directly
on to the face plate o {see Fig. 1) (a slotted disc fixing on
to the mandrel ; it is part of the furniture provided with
most lathes, even of the simplest form) with wood screws
passing through the slots from the back of the plate into

228

Turning Wood in the Lathe

the wood held flat against the face or by screwing the
wood from the front face on to a piece of wood pre-
viously secured on the front surface of the face plate.

Fig. 20.— Section through
Powder Box

Fig. 21.— Wooden
Egg-cup

When it is necessary to turn one part to fit within
another, such as the lid to fit on the box (see Fig. 20),
it is advisable to turn the hollow part of the joint first
and then turn the outer part to fit within the hollow part,
because it is easier to turn an outside part to an exact
size than it is to turn an inner surface to a precise
dimension.

Woods for Turning. — As a general rule, hard and

close-grained woods, such as
box, rosewood, holly, lime,
ebony, teak, beech, ash, apple
and pear, are better suited
for turning than the more
open - grained hard woods,
such as oak, walnut, elm and
mahogany, or the common
soft woods, such as pine,
yellow pine, spruce, poplar and sycamore.

Turning Tapered Work. — Occasion may arise when
it may be necessary to turn a tapered pin or spindle,

229

Fig. 22. — Screw Chuck

Every Boy His Own Mechanic

the taper to be gradual and even from a larger end to a
smaller one. This may, of course, be accomplished by
carefully advancing the tool nearer the centre as it
approaches the smaller end of the work, but such an
operation requires much skill and practice to be per-
formed successfully. A much easier way is to " set over "
the tailstock, that is, to move it in such a way that the
centre carried by it is not in line with the centre carried
by the headstock.

Figs. 23 and 24. — Elevation and Section of
Wooden Wheel, Picture Frame, etc.

Most lathes will allow of the tailstock being set over,
in which case turning a gradually tapering article presents
no more difficulty than turning an article with parallel
sides. The amount of eccentricity given to the back
centre (in other words, the distance which the back centre
is put out of line with the front centre) governs the amount
of taper produced.

230

HOW TO MOUNT PICTURES

I WILL not trouble you with many particulars with
regard to the mounting of pictures. Engravings and
similar pictures of value are rarely mounted, but are
inserted in the frame just as they are ; but presentation
plates, cheap prints in general, and often water-colour
drawings and the like, require to be mounted on stiff paper
boards, which are obtainable in all the regular sizes,
such as 24 in. by 19 in., 30 in. by 21 in. or 22 in., 33 in.
by 26 in., and several larger sizes. The picture, etc.,
having been carefully trimmed up with sharp knife or
scissors to lines previously drawn by means of T-square
and pencil, is laid face downwards upon a piece of
clean newspaper and brushed all over with flour paste,
made by mixing a tablespoonful of flour with a cup of
cold water, and boiling until the paste becomes more or
less translucent ; or a starch paste, made in a similar
way, may be used. After a few minutes' interval, brush
on lightly a second coat of paste. What is wanted is not
a thick coat of paste, as that would squeeze out and prove
a nuisance, but a well-worked-in thin coat, the moisture
in which will make every part of the paper amenable to
pressure.

See that your fingers are perfectly clean, lift up the

231

Every Boy His Own Mechanic

pasted print, turn it over, and lower one edge of it into
the position already marked with faint lines on the
mount. Then let the rest of the print come into
contact, cover the whole with a piece of perfectly
clean paper, and rub with a clean handkerchief or
duster from the centre so as to expel all air and make
the print lie perfectly flat. If any paste oozes out
at the edges of the print, wipe it off rapidly with a
perfectly clean sponge or cloth and clean water. Cover
the print with a fresh piece of paper (the old piece pro-
bably has some paste on it which might spoil the
picture), and place under a pile of books or in a

press to dry.

There is a trick of stretch-
ing the print when laying it on
a mount. I have fre-
Sri::r« q^ently adopted it,
PAtTL o«^ and find it to answer

StCCOTINE-

very well, but the
Fig. 1.— Stretching Print on mount needs to be stout to

Mount (also applicable to _ n i •

Straining Drawing-paper on resist the pull of the print.

°" ' With a brush or pad of clean

cloth, rub some water over the back of the print, but leave
perfectly dry a margin about 1 in. wide at all four edges
{see Fig. 1). Allow two or three minutes for the moisture
to expand the paper. Apply some really strong paste
(seccotine or a similar cement is better) to the dry margin,
and very carefully lay the print on its mount. Gently
smooth out any wrinkles on the margin of the print, but
do not touch the centre part, however hopeless at this
stage the job may look. Put it away for a few hours to

232

r 1

I WLT THIS CENTltE.-
I PA.R.T WITH CLtAN '
I V/A>TiR. I

I I

1 I

How to Mount Pictures

dry, at the end of which time it will be found that the paper
has considerably contracted, and the print is now as taut
as a drumhead,. As a matter of fact, the parchment heads

Fig. 2.— Mount-cutter's Knife

of certain instruments are stretched taut by a similar
method.

Mount Cutting. — Cut mounts of many different
materials, sizes and shapes can be had from picture-
framing shops. A touch of seccotine is the best means
of securing prints to the backs of such mounts. Should
you be sufficiently ambitious to attempt to cut out a sunk
mount for yourself, you will need a very thinly ground
penknife, and had better spend ten minutes in making
it extremely keen on a knife-polishing board, wiping it
on a duster when

finished. The proper ^^^^^^^ ^^^^^

tool is the mount-
cutter's knife shown
in Fig. 2 ; the steel
blade has a very
keen edge, and
slides in and out of
a wooden handle,
at one end of
which is a brass ferrule which takes the clamping
screw. For straight mounts, the knife is guided
along in contact with a straightedge ; for curved mounts

233

[

Fig. 3. — Diagrams showing how Bevel of Sunk
Mount affects the Apparent Thickness

Every Boy His Own Mechanic

everything depends upon the worker's skill, and I do not
advise you to try, as the result is not worth the expendi-
ture of time and material in practising. According to
the angle at which the knife is held the sinking is given
an effect of thinness or thickness [see Fig. 3).

Setting Out an Ellipse. — Oval mounts need to be
set out with pencil before attempting to cut them ; in

my opinion
they are best
avoided, but
as I know
many people
like them,
and as ellip-
ses are often
wanted in
mechanical
work, I will
show the
most prac-
ticable method of setting them out ("oval" means
really egg-shaped, whereas what are known as " oval "
mounts are truly elliptical). Place the mount on a
drawing board and draw a horizontal pencil line
about midway between the top and bottom edges.
Mark off on this two points a and b (Fig. 4) to
represent the length of the oval (the "major axis"
in geometry). Mark a centre point between a and
B as at c, and with the T-square or set-square drop
a line at right angles to the point d. Now c d will be
exactly half the depth of the opening required (by the

234

Fig. 4. — Drawing an Ellipse with Piiss, Thread
and Pencil

How to Mount Pictures

way, I advise you to cut the opening first on common
white paper, and place it over the photograph or picture
to see whether you have struck the right proportion).
With compasses measure from c to b, and, without alter-
ing them, with d as centre, make two marks on the major
axis as shown, and drive in a pin or needle at each of the
intersecting points. Pass over the pins a loop of thread,
of such a length that when it is
stretched downwards by means
of a pencil the latter just touches
D. There will now be a triangle
of thread, and by using the pencil
to keep the loop taut and at
the same time moving it about
round the pins it will be found
to trace an ellipse, as shown.
Probably many of you are quite
familiar with the method, but
I have often found that boys
when attempting it do not know
how to go to work when given
definite lengths for the major
and minor axes. On a large scale, the method
can be used to set out garden beds, using posts
instead of needles, string or rope instead of thread,
and a dibber or poker instead of the pencil. The
illustration (Fig. 4) shows a thread not looped but
secured at its ends to the pins. Some experienced
draughtsmen prefer this method.

White and Gold Lines on Mounts. — Good effects are
sometimes obtained by mounting prints and water-colours

235

Fig. 5. — Using a Draughts-
man's Ruling Pen

Every Boy His Own Mechanic

on brown mounts, a simple line of white being run
round on the mount half an inch or more from the picture.
Such lines can be drawn with diluted Chinese white used
in a draughtsman's ruling pen (Fig. 5), but the job needs
to be done quickly, as the white soon clogs the pen and
frequent cleaning out will be necessary. An ordinary
writing-pen nib may also be used. For gold lines on
picture mounts, rule the lines with gum water, allow to
set, but not to dry, breathe on them, and at once dust
over them some gold bronze powder ; a better and more
permanent effect is obtained by dabbing gold leaf on the
gum lines, in which case the gum needs to be strong and
to have a little sugar dissolved in it. Edges of mounts
can be gilt in the same way, or strips of gold paper may
be gummed on.

236

SOME EASY THINGS TO MAKE IN WOOD

A Lamp Bracket. — A simple but solid lamp-bracket is
shown on the next page. It is made wholly of |-in.
material, which, naturally, will be a trifle thinner than
this when finished. There are four pieces. The long
wall piece is 7 in. long and 2| in. wide ; it will require to
be cut a little larger than the dimensions here given to
allow of planing up. The top shelf is 3| in. square, and
its shape is shown in detail in the plan (Fig. 3), while
Figs. 1 and 2 are two elevations in which the shelf is
shown simply in edge view. The lower shelf should be
made originally as a part of the back piece so that it will
be exactly the same width. It is 2 in. from back edge to
front edge, but | in. of it is housed into the back
piece, and its outer corners are rounded off {see Fig. 4).
The bracket piece under the top shelf will be cut from
a piece measuring 1| in. by 2| in., and the method of
striking the curve to which it requires to be cut is given
in Fig. 2, where d is the centre for the compasses.

First plane up all the stuff and get it true and square.
Dealing with the back piece first, Fig. 1 shows how the
foot of it is struck to a curve, the centre for the compass
being 1| in. up and 1\ in. from either side. The curve
can be worked with a saw if the wood is left originally a
trifle long, or perhaps it will be easier to execute it with

237

Every Boy His Own Mechanic

a sharp chisel, but the square shoulders | m. from the
bottom could be cut in with a fine saw. A groove should
be cut for the bottom shelf exactly as shown, its depth
being half the thickness of the material. Nothing need
be said about the bottom shelf c — its shape is quite clear

Figs. 1 and 2. — Front and Side Elevations of Lamp Bracket

I I

a^"-{--^

17 LJ.i

^U^

Fig. 3.— Plan of Top Shelf

Fig. 4. — Section through

Back piece, showing Plan

of Under Shelf

^38

Some Easy Things to Make in Wood

from what has been said already. The top piece is per-
fectly square except for the hollowing out of the two front
corners executed with saw or gouge. It is simply laid
on the top of the back piece squarely, and nailed or screwed
on. The bracket piece is cut to the curve shown, and
should be screwed on, there being, say, one screw through
the top and two inserted from the back.

Folding Book Rack. — The book rack shown in Fig. 5
is a base with plain or bevelled edges and two hinged ends.
If desired these ends can be permanently fixed upright
by means of screws inserted from underneath. Fig. 5 is

— 1' <s"-

-HIBCL

KiKGL

J* i- J-

T CKl

5 — -

■7''-

Figs. 5 and 6. — Two Elevations of Folding Book Rack 3i

a front elevation, and Fig. 6 an end elevation, while Fig. 7
is an enlarged end elevation giving the construction lines
by means of which the end pieces are correctly set out.
The base is 1 ft. 9 in. by 1\ in. (finished sides). The bevel,
or straight chamfer, is worked on it with a plane. Each
end piece is 6 in. high by 5 in. wide (finished), and very
little need be said about its shape, because Fig. 7 gives
full particulars.

The perforated star adds considerably to the effect.
It is set out as shown in Fig. 6, a circle being drawn and
the radius stepped round with the compasses to give six
points, the alternate points being then connected as

239

Every Boy His Own Mechanic

shown. A hole could be bored in the middle of the star,
and the points then cut out with saw or chisel.

The end pieces are each connected to the base piece
by one brass hinge, although two hinges each would be
an improvement. The hinges are carefully laid in position
marked round with a sharp knife, and recesses carefully
chiselled out to receive them. Drive in the screws straight
so that their heads come perfectly flush.

Stool and Doli's Carriage. — Fig. 8 shows just the

sort of article in wood the
boy mechanic can make
and at the same time give
much pleasure to a young
brother or sister. It is a
stool 11 in. high, having a
top 16 in. long by 9 in. wide,
the end pieces being cut
from pieces approximately
11 in. long and 8 in. wide
(see Figs. 9 to 11). To give
the whole thing strength the
sides are preferably dovetailed in, and they will require to
be cut to the shape and dimensions given by a full-size
drawing ; they can be got out of pieces each about 1 ft.
3 in. long and 5 in. wide. I shall not anticipate the
information on dovetailing given in a later chapter,
but may remark that the dimensions given in Fig. 12
will assist you in making a good job of it. If you do not
feel up to the dovetailing, simply notch out the end
pieces with a saw to receive the sides, and connect all
together with screws or nails.

240

Fig. 7.— End of Book Rack

Simple Bookrack with Hinged Ends

(For Working Draunngs, see page 239)

Pair of Dwarf Steps

(For Working Drawings, see page 243)

Some Easy Things to Make in Wood

A Pair of Dwarf Steps. — A pair of dwarf steps is
very useful in a study or hall or workshop where articles
just out of ordinary reach are continually being wanted.
The steps shown on p. 243 stand about 18 in. high, and the
two elevations given in Figs. 13 and 14 give most, if not
all, of the essential dimen-
sions. The steps will be made
wholly of 1-in. pine, which,
when planed up, will be | in.
thick. The front legs are 4| in.
wide, and have a total length
of about 22 in. Therefore, at
least 3 ft. 8 in. of this width
of stuff will be required. The
back legs are about 1 ft. 6 in.

long, tapering from 3^ in. at the pig. 8.-StooI and Doll's Carriage

Figs. 9 and 10. — Two Elevations of Stool

Fig. 11.— Plan of Stool
9

Fig. 12.— Side of Stool
Dovetailed to Leg

241

Every Boy His Own Mechanic

top to 2 1 in. at the bottom, as shown in the side elevation,
and both of them can be cut from a piece 18 in. long and
6 in. wide. The one step and the top may be about 6f in.
or 7 in. wide, although the step can be 1 in. narrower if
desired. The top will be about 1 ft. 4 in. long, whilst
the step will need to be accurately fitted in place, and
will be about 1| in. shorter than the top piece.

To get the various bevels correctly marked out, the
best plan would be to draw the side and front elevations
on a floor or on a table top with a stout pencil or crayon ;
or perhaps a piece of packing paper large enough for the
purpose can be found. From the full-size drawing all
the bevels can be transferred by means of the tool
known as the sliding bevel, or even by means of a 2-ft.
folding rule as long as the joint is not too easy. First
draw a rectangle, letting the top and bottom lines fall on
the ground line and upper surface of the top step in
Fig. 13; then by measurement along both the horizontal
lines, the points where the sloping sides start and finish
can be easily ascertained and the correct angles deter-
mined. The wood can be actually applied to the full-
size drawing, and risk of error in transferring measure-
ments thereby reduced considerably. The side pieces
must be cut to shape and " housed," that is, grooved to
receive the ends of the steps.

There is more than one point in the construction in
which you can please yourself. Where the front legs
overlap the back ones just under the top, the two may be
halved together, or halving may be dispensed with, and
the two simply nailed or screwed together. The halving
should be done after the back legs have been connected

242

Some Easy Things to Make in Wood

together. The steps are given rigidity by two rails which
connect the back legs together— a top rail 14 in. by 4 in.
and a lower rail 14 in. long by 1| in. by 1 in. Both these
back rails arc notched in, as clearly shown in Fig. 13,
and nailed or screwed on. The top notch may, if you
like, be wholly removed with the saw, whereas the bottom
one requires two saw cuts and careful paring with a
chisel.

\^ e%-n

Figs. 13 and 14.— Two Elevations of Dwarf Steps

There is no need to go into every detail of the construc-
tion. It is a simple article, which there will be no diffi-
culty in making, and which can be modified to suit your
own particular requirements. Only two parts are rounded
or chamfered on the edges, namely, the top and the step.
There is a hand hole in the top piece, the position of which
requires to be set out before cutting. The simplest way
of making the hole is to bore a centrebit hole at each
end and connect the two holes with a fine saw, or to
bore a row of centrebit holes, and complete the slot by
paring with a chisel. It makes a good job to house or

243

Every Boy His Own Mechanic

groove the underside of the top to receive the ends of
the sides.

Bathroom Shelf. — Figs. 15 and 16 are almost self-
explanatory. The article has two ends (for economy in
cutting out, reverse the pattern of one as at b) with the
shelf tenoned into them {see Fig. 17). In the fitment

Fig, 18. — Bathroom Fitment
with Glass Shelf

1 -; '

i_Lr-^ i J.

Figs. 15 and 16. — Two Elevations of Bathroom Shelf

Fig. 17.—

Tenoned End

of Shelf

shown by Fig. 18, the two ends are nailed or screwed to
the back piece, and the actual shelf is a plate of glass
with its front edges rounded off, supported in grooves in
the two ends or on little ledges or fillets nailed or screwed
to them.

244

ETCHING A NAME ON METAL

It is a very simple matter to etch your name on a knife-
blade, and I used to find the job great fun. The principle
is very simple. The blade is to be treated with a chemical
that will act upon the steel, and those parts of the metal
that are to remain as they are must be coated with some-
thing that will resist the action of the chemical. Now
there are many chemicals that act upon steel, copper and
brass, and among them are the following : (1) equal
parts of pyroligneous acid, nitric acid, and water. (2)
diluted nitrous acid. (3) 2 oz. of copper sulphate, | oz.
of alum, J oz. of salt, | pint of vinegar, and 40 drops of
nitric acid. These are among the simplest mixtures used
for the purpose, and there are many more complicated
ones ; but the substance I used when I was a boy was
something very much more simple. It was ordinary blue-
stone (sulphate of copper), a big lump of which can be
bought from a chemist or an oilman for a trifle. It h
made leady for use by crushing a little bit of it to powder,
adding a tiny pinch of salt and moistening with water;
or you can dissolve a larger quantity of the bluestone
crushed fine with a little salt in a bottle with hot
water. If you continue to add crushed bluestone
until the water will not dissolve any more you will
form a saturated solution, and this will be excellent

245

Every Boy His Own Mechanic

stuff for etching knives, steel tools or anything else
made of iron or steel.

Etching acids and solutions can be applied with a tiny
bit of sponge or tissue paper tied to the end of a thin piece
of stick, or, if it happens to be convenient, the article to
be etched may, after careful preparation, be dipped into
the solution. Of course, the longer the time for which
it is dipped the deeper will the etching be. It is not usual
to have the etching acids very strong unless particularly
quick results are required. It is generally better to dilute
them with water so that the effect of the corrosion may
be carefully watched and stayed just at the right moment.
Plunging into water and stirring round vigorously im-
mediately stops the action.

If the whole of a knife-blade or tool unprepared in any
way were immersed, the whole of its surface would be
etched or corroded, and one result would be that the keen
edge would disappear. Before dipping the blade every
part that is not to be touched by the acid must be covered
with something (known as the resist) which is not affected
by the acid. In roughly etching a name on a knife-blade
with powdered bluestone and salt, all that most boys do is
to rub a thick film of soap over the blade, scratch the name
in the soap right through to the steel beneath, fill up the
grooves so made with the powder slightly moistened,
and leave the whole for a few minutes. This is a rough
and ready method, and not one which is likely to lead to
a particularly neat result.

Say, for example, there is a steel, copper or brass plate
to bear your name which it is proposed to screw down on
the lid of a tool-box or school locker {see Figs. 1 and 2),

246

Etching a Name on Metal

you will want the effect to be as artistic and the workman
ship as neat as possible. The soap method would be a
trifle too rough, and, instead you had better coat the whole

liNi&.MlJSCiRAyt

Fig. 1. — Etched Name-plate

of the plate (back and front and edges) with japan black,
a small quantity of which you can obtain very cheaply at
an oilshop. This should have several hours in which to
dry hard. The name will be written by means of an
etching needle, a piece of knitting needle held in a suitable
handle, and finely but roundly pointed, or an old bradawl
or anything similar can be sharpened up on a stone flag
to answer the purpose. A sharp point is not necessary,
as the object is not to scratch the metal, but simply to
remove the resist and lay the metal bare. Having wiitten

Fig. 2. — Etched Name-plate

the name, brush over the letters to remove any loose
particles of the resist that might be clinging to the plate,
and the latter might then simply be placed in a saucer

247

Every Boy His Own Mechanic

and the etching solution poured on until the plate is
covered. It is impossible to say how long the plates
should be left in the acid, but if you make the solution

niirrm»iiM|,.,,,,,jiiumii|,,,,,,,,,H^iBii|,,,.^{iiiun.n.,,.,.jMMaiiu„„.^^^^ }uuait^,;;;;4muii

MEC EDWARDS

ti..mwnnJ"l""'^,Nnn„l""i"'M^,T,#"^'HnrW"""'"L,,MnJ"'^ .|imffll|„„„„|limilH ^

Fig. 3. — Etched Name-plate with " Stopped-out " Border

fairly weak, you can leave it in for ten minutes and still
be on the safe side. If you don't wish to immerse the
whole plate, you can dab on the acid with the little device
already mentioned, or you can build a wall of modelling
wax or candle wax around the edge of the plate and pour
m the acid into the shallow recess so formed. Obviously,
there will be no need to coat the edges and back of the
plate unless the whole-immersion method is preferred.

'^ — W

mm^

!Ai]TrTT7iini

imimTnmmrTTniiiiiMiiiiiuiiimitnnmTniii/iiiiiiiwiiiiiiiiiiimmnm

y£. y^Q£SON

liriUHIItiUlllllllimillllllllllllllUIKKIIIIIKIIIIMIIIIIKItaUllllUUi:

Fig. 4. — Etched Name-plate with " Stopped-out" Ornament

It is an easy matter to sponge off the acid and renew
the treatment if the biting in is not sufficiently deep.

248

Etching a Name on Metal

Rinse with water when^the right depth of etching is
reached.

Finally, you can wash off the japan black with some
turpentine or paraffin oil, and the etched work be revealed
in its finished state.

You can try all kinds of fanciful effects by etching
some parts of the design more deeply than others ; for
example, you could have a border line very slightly etched
with your name more deeply etched inside the line. To
get this effect, you would proceed in the ordinary way,
and after a slight action had taken place, you could wipe
out the acid from the border line, and coat the line with
wax or japan black, allowing it then an hour or tvro in
which to dry and afterwards renewing the etching action
on the name. This method is known as " stopping-out "
(Figs. 3 and 4 illustrate examples), and is very generally
practised in commercial etching.

249

VARNISHING AND POLISHING

Varnishing. — I do not propose to say much about
varnish. You will not be making your own varnishes,
but will use what you buy ready made ; indeed, oil
varnishes cannot be made at home, as the linseed oil needs
to be made hot before the varnish gums are introduced,
and that is much too risky a game to be tried at home ;
besides, the making of oil varnish is an art beyond
the amateur. All sorts of names are given to oil
varnishes, but they mean very little. There is only
one course if you want good varnish; go to a reliable
dealer in decorators' supplies and pay a fair price.
Tell him what you want the varnish for, and leave the
choice to him.

In applying oil varnish, avoid dust. Do not work the
stuff too much with the brush, and do not attempt the
job in a room that is cither cold or damp. If you think
that the varnish is too thick, try standing it in a slightly
warm place to see whether it gets a trifle more workable,
but do not add any turpentine or oil to it or you will
probably spoil it. If you think that two coats will make
a better job than one, allow the first to get hard, and
before applying the next, rub over with worn glasspaper
or with a piece of wet felt or cloth on which has been

250

Varnishing and Polishing

sprinkled some pumice powder. As in the case of the
enamel paint previously mentioned, apply neither too
much nor too little.

Oil varnish can withstand a lot of wear and weather ;
on the other hand, spirit varnish, which is generally a
simple solution of shellac, etc., in methylated spirit, and
can either be bought ready made or prepared at home, can
seldom resist either, and is, therefore, used chiefly on small
articles where a bright finish is desired, but which will
not be liable to rough usage or come much in contact with
water. It needs to be applied quickly, and it dries very
often almost as soon as it is on. The coat of shellac or
other gum or resin which it leaves on the work is often
rather brittle, but for all that spirit varnish answers
excellently for small and fancy articles of a great many
kinds. Following are two or three recipes which you may
find useful. If you try them, see that the gum, etc., is
quite dry, is crushed up fairly fine, and that the bottle
containing the ingredients is kept in a nice warm place
such as near a chimney breast, near a hot- water, pipe or in
a heated linen-cupboard. Give the bottle a shake up
every day, and finally leave it for as long as possible for
any impurities to sink to the bottom.

A favourite spirit varnish is "brown hard varnish."
The name means anything or nothing, and I expect there
are scores of different recipes for it. Here is one of the
best : Dissolve 4 oz. of orange shellac, 1 oz. of resin, and
^ oz. of gum benzoin in 1 pint of methylated spirit. An
excellent reddish-coloured varnish is made by adding a
touch of bismarck brown to the above, or 1 oz. of dragon's
blood. You can get a yellow tinge by adding a little piece

251

Every Boy His Own Mechanic

of gamboge, a lump of which can be got from the chemist
very cheaply.

There is also a '\ white hard varnish," and for this you
can dissolve 4 oz. of gum sandarach and 2 oz. of gum-
thus or Venice turpentine in 1 pint of methylated spirit.

The following is a bright varnish which is not so brittle
as the usual spirit varnish : — Dissolve 1 oz. of resin, 2 oz.
of gum sandarach, 6 oz. of shellac, and 1 oz. of Venice
turpentine in from 1 to 1| pints of methylated spirit.

An everyday spirit varnish is simply a solution of a
few ounces of shellac in 1 pint of methylated spirit.

Polishing. — I wonder how many of my readers will
be ambitious enough to attempt what is known as french
polishing. I shall merely outline the process here. It
gives a much more beautiful finish than varnishing, and
consists of applying a coat of shellac to the work and then
bringing this to a lustrous polish by means of friction.
You must first prepare the surface with glasspaper and
then fill up the grain by rubbing over it a rag dipped into
a creamy paste consisting of whiting and turpentine.
Rub away the surplus " filler," and see if there are any
nail holes or defects that require to be made good. If
there are, you can fill them with melted shellac, although
the proper material to use is a hard stopping known as
beaumontage, and containing shellac, resin, beeswax, and
colouring matter. This can be bought ready-made, and
is run into the defects by means of a hot iron, cleaning off
the surplus when cold with a scraper and glasspaper.

The job is first to give the work a sound, even coating
of shellac. This is done by going over it many times with
french polish, which can be bought ready-made or pre-

252

Varnishing and Polishing

pared at home by dissolving 6 oz. of shellac in 1 pint of
methylated spirit. The polish is kept in a bottle, and
when required for use is allowed to drip into a little pad
of wadding, which should then be covered with a piece of
clean dry rag, previously thoroughly well washed free
from dirt and dressing. By having the rag of ample
size and giving it a twist occasionally, the polish can be
squeezed out of the rubber on to the work. The rubber
meets with some resistance in use, and, to lessen it, you
may apply just a spot of raw linseed oil to its face, but
the less oil you use the better. Work the rubber in a
series of overlapping circles or figure eights, and when
you have got on as much shellac as you can, let the work
rest for a day in a situation protected from dust, cold
and damp. Give it another coat and yet another, ob-
serving the precautions before mentioned, and when you
are satisfied that you have obtained a good body of shellac,
you can start the particular stage of the process in which
trouble, if not already met, makes its entry !

Now what you have to do is to wash the film of shellac
with spirit and polish it by the passage of the rubber,
but you must avoid washing it all away. You will need
a clean outer rag — or two or three rags one over the other
— on the polish rubber, but do not add any more polish.
Add, instead, a little methylated spirit, and, as it dries
out, add a little more^ and continue in this way until, as
the job nears its end, there will be very little polish left
in the rubber, the spirit having taken its place. The
rubbing continues until the polish is attained. I doubt
whether a long chapter on the subject would succeed in
teaching you the polisher's art. I shall make no attempt to

253

Every Boy His Own Mechanic

do that, however ; I have simply outlined the process, and
you can experiment to your heart's content if you so wish.
French polishing is one of those jobs that ought to be easy
from the description of how it is done, but— wait and see.

There is one little trick (it is not used by the best
polishers) by which you can avoid some of the risky
later stage — the spiriting-out — and yet get a passable
effect. Having progressed a little in the polishing of the
shellac film, do not continue with the rubber, but brush
on a coat, or even two, of a glaze or varnish made by
dissolving 6 oz. of gum benzoin in 1 pint of methylated
spirit. Of course the result is not so good as that given
by the true french polish.

Dull Polishes. — French polishing is often garish in
its effect, but can be made to look very good by dulling
it with friction from a pad of felt made wet with linseed
oil and sprinkled with pumice powder or the finest emery.

Probably the best dull polish is also the simplest, and
is obtained by rubbing on, with a rag or a brush, some
beeswax dissolved in turpentine. You simply rub it on,
and then with a cloth or another brush do your best to
rub it off again. Repeat the process as many times as
you like, and with every repetition the quality of the
polish will improve. After a time you need not apply
more wax, but simply more friction.

Rubbing with linseed oil, either raw or boiled, in much
the same way as wax polishing is done, will, in course of
time, produce a dull polish ; but the work is laborious,
and will require many applications and plenty of elbow
grease. It is the ideal polish for finishing the woodwork
of tools, particularly plane stocks.

254

MAKING HUTCHES

Most boy carpenters try their hand some time or other
at making a rabbit hutch, which occasionally is nothing
better than a lidless box placed on its side with the opening
covered in partly by wire netting and partly by a wooden
door, there being a partition to separate the " living-

Fig. 1,— Rabbit Hutch

room " from the " bedroom." In Fig. 1 is shown some-
thing a trifle more ambitious, although, of course, it is
little more than a box divided up as above explained.
Fig. 1 is a view of the hutch complete ; Fig. 2, a front
elevation ; Fig. 3, a cross section ; Fig. 4, a horizontal
section showing the dividing up of the hutch into two

255

Every Boy His Own Mechanic

apartments ; and Fig. 5 is another front elevation of the
hutch with the outer door open or removed to show the
inner door, to which reference will be made in due course.

The remaining illus-
tration (Fig. 6) shows
exactly how the
hutch is arranged
internally.

You can either
build up the box
from any material
you happen to have
at hand, say ^ in.,
I in., or f in. thick,

-J H

Fig. 2. — Front Elevation of Hutch

or you can adapt a
box or packing case

to your needs. Assuming the latter, remove the lid, and very

carefully prise off one of the sides by means of an old chisel

or screwdriver. The lid and side will help to make the roof

and to increase the height,

if necessary, by adding tri-
angular side pieces c (Fig. 6)

and back piece b. To hold

these in place, two strips d at

each of the internal corners

will be necessary, nailing these

with fine wire nails to the

lower part of the box, as will

be readily understood from"^-^

the illustration. You can

please yourself whether you

256

Fig. 3. — Cross Section through
Hutch.

Making Hutches

r b

DA^f- COMPAniiajT

-• ' \fflms

use another strip near the front or whether you secure
c to the piece underneath by driving a nail down through
c from the top edge.

The partition f should be in one piece if possible,
but if obliged to

make it in two, you
can connect them
together with a
couple of strips at
right angles to the
joint. The partition
will be secured with
two or three nails
driven through from
the back of a and b
and with a couple of
nails driven through
from underneath.
Before securing the
partition, however,
it is necessary to
cut out a square of
4 in. or more, as
indicated at g, to
give access from one
apartment to the
other.

Fig. 4. — Horizontal Section through Hutch

Fig. 5. — Front Elevation of Hutch, with
Outer Door Removed

You can next proceed with the lid, and as you are un-
likely to be able to find a board sufficiently wide, you will
need to build it up of two or three widths and nail them
down to a couple of fillets which will come on the under-

K 257

Every Boy His Own Mechanic

side of the roof, and be, therefore, hidden. In the section
(Fig. 3) the roof is shown as being flush at back and front,
but a better idea is to make it as shown in the general
view (Fig. 1), that is, with a projection at front and back
and also at sides. Always remember that damp is the
great enemy of the domestic pet. Poultry, rabbits, dogs
and even bees soon lose their health if obliged to exist in
damp surroundings, and it is therefore an advantage to

carry out a roof as
shown for the pur-
pose of throwing
off rain. You can
fit the roof, but do
not fix it yet awhile,
and remember to
take care in decid-
ing the height and
arrangements of the
outer door that it
is not prevented
from opening by
the front over-hang of the roof. I mention this point
because you are not likely to carry out the design in
every detail as it is here shown ; you should study the
requirements for yourselves, and make the instructions
and illustrations here given merely a basis for your own
particular adaptation.

The front of the hutch consists of two parts : (1) a
frame h with wire netting, or even straight vertical wires
about 1 in. apart, and (2) a wooden door which covers
just about half the entire width of the front. The frame

Fig. 6. — Internal Arrangements of Hutch

Making Hutches

on which the wire netting is stretched is simply four pieces
of |-in. or f-in. stuff, halved at the ends to make good
joints. It is either nailed in or hinged on.

Make the frame and attach the wires or netting before
building the frame into the hutch ; it is secured with
nails to the edge of the bottom board and to the edge
of the side piece. A couple of nails through the roof when
this is finally fixed will strengthen the job.

You will note in the illustrations that there are two
doors, an outer door l, and an inner door m. The outer
door is hung from a post or strip and nailed to the front
edge of the side piece. It should close flush with the
frame h, and when it is open, there will, of course, be
discernible a space between the right hand edge of h and
the partition. You can quite see that in frequently
opening the door to handle the rabbits or for purposes
of cleaning the hutch, you would disturb any occupant of
the sleeping apartment were it not for the inner door.
A. doe with new-born rabbits must not be disturbed.

The inner door opens vertically, and is simply a piece
of board hinged to a horizontal strip which fits in the
notch shown to the extreme right of Fig. 6, and is nailed
to the front edges of side and partition. At the front
edge of the partition underneath the strip last men-
tioned is nailed a vertical strip flush with the front
face of the door m.

Little more need be said, but you will notice in Fig. 1
a wedge through a staple, and in Fig. 2 a small padlock
through a staple. You will please yourself which of these
you adopt. The staple is driven into the strip on the
front of partition f and a hole or slit is cut in the outer

259

Every Boy His Own Mechanic

door to receive it, all being fastened up by means of a
wedge or padlock as shown.

All the woodwork being finished, you can paint the
outside of the hutch if you so wish, and cover the roof
with some tarred felt, which should project slightly from
the boarding to which it is tacked down. See that venti-
lation holes are bored high up in the back and side of
the hutch. I have not shown any dimensions, because
these will, of course, depend upon the box which you

propose to adapt ; but
you will scarcely wish to
make a hutch from a box
smaller than 3 ft. long,
and about 2 ft. deep.

Another Hutch. — The
hutch which I show in
Fig, 7 was specially de-
signed for use as a ferret
hutch, but is generally
applicable to many different uses. Fig. 8 is the front
elevation, and Fig. 9 is a cross section. The hutch can
easily be converted from a box or packing case, or can
be built up of f-in. or | in. boards. A few suitable
dimensions are suggested in the illustrations, but they
can be varied to any extent. Four legs will be required,
and these may be of square or rectangular section and
of any suitable thickness, 2 in. by 1| in. being suggested
in the illustrations.

You will note that these legs require to be
notched out so as to give better and stronger support
to the hutch. They are secured by a couple of screws

260

Fig. 7.— Ferret Hutch

Making Hutches

or nails inserted from the outside of the legs into the side
of the hutch.

A strong packing case, 3 ft. long and 18 in. deep, is
suggested in the illustrations, but you will use just what
you can get as near to these sizes as possible. The front
of the box consists, first of all, of a rectangular frame made
of ^-in. by 1-in. stuff, and halved at the four corners as
shown in Fig. 10. At the centre will come an upright

Fig. 8.— Elevation of Ferret Hutch

Fig. 9. — Cross Section
through Ferret Hutch

piece, which will be halved into the frame at top and
bottom, as shown in Fig. 11 ; it will carry two buttons,
one for the wooden door to the right of the hutch, and the
othei for the frame to the left. The framing is made of
1-in. stuff, lapped at the ends, and covered with quite
fine wire mesh. The door to the right will probably have
to be built up of two widths, nailed to strips or ledges,
which are indicated in dotted lines in Fig. 8. In the
middle of the door is a small rectangular opening of any
size, but not less than 5 or 6 in. across, and this also should

261

Every Boy His Own Mechanic

be covered with very fine mesh, or with wire gauze. It
will be obvious that the upright in the middle of the front
will come on the front edge of a partition piece, which
can be secured in position
exactly as in the case of
the rabbit hutch already
described, and in this par-
tition there will need to be
made a small hole so that
the animals can pass from
one compartment to the
other. By means of the

big doors shown, it will be an easy matter to get at the
hutch for cleaning purposes.

Fig. 10.— Joint
in Hutch
Framework

Fig. 11. — Joint

of Front Upright

to Framework

262

HOW TO SILVER GLASS FOR MIRROR
MAKING

I SUPPOSE most boys have wondered at times how a
piece of glass is converted into a looking-glass, and many-
have got hold of recipes and have tried their hands at
the job. A state of " chemical cleanness " is essential
at every step and in every one of the materials used, and
this is not easy to attain. In the old days, a sheet of
lead-foil was laid down on a special bench or table and
treated with plenty of mercury, which amalgamated with
the lead to produce a bright alloy, on to which the cleaned
glass was floated. Glass easily floats in mercury. Next
the bench had to be tilted to drain off the superfluous
mercury, the degree of the tipping being increased day
by day until, in the course of perhaps three or four weeks,
the alloy or amalgam was dry. But the boy mechanic is
not advised to play about with mercury for any length
of time, as its vapour is poisonous. Nowadays, mirrors
are made by precipitating silver from a chemical solution
upon glass that has been made perfectly clean.

Probably the safest and easiest method is the one
here described, for which you must get from the chemist
a bottle of distilled water, 180 grains of silver nitrate,
150 grains of caustic potash " pure by alcohol," 75

263

Every Boy His Own Mechanic

grains of glucose, and a small quantity each of nitric
acid and of liquor ammoniae. No other method employs
cheaper or fewer ingredients. Potash and glucose are
too cheap to buy by the grain in the ordinary way,

but you need to
be correct in your
proportions ; but if
you have a delicate
balance you can
measure out the
ingredients for
yourself.

First clean three
tumblers and a
small bottle with
dilute nitric acid,
which will leave
them chemically
clean, and then rinse
them with distilled
water.

In tumbler No. 1 place the silver nitrate and 3 oz. of
distilled water (1 pint of water is 20 oz.). See that the
nitrate is all dissolved, and then transfer | oz. of the
solution to the bottle (No. 4.) Dont let this solution
touch the fingers or it will blacken the ski^i. The
discoloration will wear off in the course of a few days.

Silver nitrate is the " lunar caustic " of the chemist's
shop, and is useful in certain cases of skin affection, the
blackening being partly due to the formation of metallic
silver ; in mirror making the glucose solution acts much

264

-The Solutions used in
Silvering Glass

How to Silver Glass for Mirrors

in the same way as the cuticle of the skin in " reducing "
the metallic silver.

In tumbler No. 2 put the potash with 2| oz. of dis-
tilled water.

In tumbler No. 3 put the glucose and add 2| oz. of
distilled water.

The three tumblers and one bottle are shown in Fig. 1.

To tumbler No. 1 add a few drops of the ammonia to
cause a muddy brown colour to appear. Then add more
ammonia, drop by drop, until once again the solution is
clear and bright. For pouring out drops of the liquor
ammonise loosen the stopper (never use a cork, as it
would soon be eaten through) and tilt the bottle to and
fro to allow a drop or two to leak out.

You remember that | oz. of the silver nitrate solution
is in a bottle (No. 4). Add some of the contents of this
bottle to tumbler No. 1, drop by drop, until for a second
time the solution loses its clearness ; when held up to the
light it will be of a translucent yellow colour.

Next, to tumbler No. 1 add the potash solution from
No. 2, the result being a blackish liquid. Again add
ammonia, drop by drop, and stir with a chemically clean
glass rod all the time until the liquid is much clearer and
the precipitate (a powder falling to the bottom of the
vessel) is full of black particles. Strain the whole by
pouring it through a chemically cleaned glass funnel in
which a piece of fresh cotton-wool has been placed to
act as a filter {see Fig. 2) ; or, if this is impossible, allow
plenty of time for the precipitate to settle, and then pour
off the clear liquid. To this clear liquid add, drop by
drop, more of the silver nitrate solution from the bottle

265

Every Boy His Own Mechanic

until a very slight precipitate appears, when you must
instantly stop the addition.

The glass should be " patent " plate, and has two
distinct sides — a right and a wrong. These may be dis-
tinguished, after chemically cleaning as described, by
breathing upon them. The film of condensed moisture
will leave the right side rapidly and evenly ; this is the
best one to be silvered, while on the wrong side the con-
densed vapour will dissipate slowly and irregularly.

Get a dish — say a photographer's glass developing
dish — of such a size that it will easily accommodate the
glass to be silvered, both dish and glass being chemically
clean, of course. Set the dish level, pour in the solution,
and add distilled water to give sufficient depth. But
before immersing the glass, pour in the glucose from
tumbler No. 3, stir up, and then introduce the glass,
slanting it so that it will not carry down air bubbles with
it. The glass would ordinarily settle on the bottom of
the dish, but this must be prevented, either by two blocks
of glass seccotined to the dish at the extreme sides or
ends {see Fig. 3), or, instead, a piece of wood must be cut
out as in the sectional view (Fig. 4), and the glass be
cemented to it with pitch. (At the proper time it is easily
removed with a thin chisel carefully inserted at the edge.)
Whatever arrangement is adopted, there must be a space
of about \ in. between the underneath surface of the glass
and the bottom of the dish.

As the glass is lowered into the solution the latter
becomes of a purplish-pink colour, becoming gradually
darker. In the course of 15 to 30 minutes the silver
will have deposited on the glass, which may then be

266

How to Silver Glass for Mirrors

removed, carefully washed, and placed on edge to dry.
This accomplished, the silver may be polished for a
quarter of an hour with a pad of cotton-wool covered
with a soft fine washleather.

A silver film is deposited also on the surface of the
dish, but the greatest quantity separates as a fine powder
and is lost, from the silverer's standpoint.

The above is particularly adapted for silvering the

^«s

Fig. 2.— Filtering
the Solution.

Glsep Slips or Blooke Level of Solut lOf
Fig. 3

Figs. 3 and 4. — Methods of supporting Glass
in the Silvering Dish

speculum of a telescope or microscope, but can be used
equally well for small pieces of plate glass.

The silver film when formed must be protected, or it
will very quickly lose its colour from contact with im-
purities in the air, notably sulphur ; for this reason the film
should be coated twice with good copal varnish, after
the silver is quite dry, and when it is slightly warm. Use
a very soft brush. The mirror will reflect from both
surfaces of the film, and for certain optical work, where the
reflection is not through the glass, the film must not, of
course, be varnished.

267

WATERPROOFING TENTS, GROUND SHEETS
AND GARMENTS

Waterproofs of the oilskin kind are easily made. Most
people know that they are cotton, linen or even silk
dressed with boiled linseed oil repeatedly, but few are
aware that to get the best results only the " double-
boiled oil " should be used, this giving the familiar yellow
colour, drying better than ordinary boiled oil, and having
more marked waterproofing qualities. To get black
waterproofs, you merely add to the oil some oil black or
vegetable blacky but not lampblackc

Let us assume that you are going to waterproof a
tent canvas or a number of ground sheets which are to
be used on a camping expedition. If you have not the
use of a suitable heated kitchen, in which to hang the
sheets for drying, do the work on a sunny day and hang
them in the open. Spread the canvas, new and unwashed,
on a table, or on some clean boards propped up to form
a bench, have the oil in a wide vessel close at hand, and
mix nothing with it but the colouring matter if this is
needed. Apply the oil to the canvas, etc., by means of
any suitable bristle brush, such as an old clothes-brush.
Don't try to saturate the cloth, but do your best to get
a good even coat. As you finish the pieces, lightly fold
them and push them out of the way until all have been
done. Then pull them out straight and hang them up

268

Waterproofing Tents

to dry, a process that will take from one to several days,
according to the drying facilities, weather, etc.

When thoroughly dry, the canvas is shaped, sewn and
otherwise worked up, and is then given two more coats
of the oil, allowing each to get thoroughly dry. If much
used, the sheets can be given a reviving coat every summer
to keep them in good condition. Of course, if you like,
the sheets, garments, etc., can be made up wholly un-
oiled, and the oiling done as a finishing process, but there
is a great likelihood of wrinkles and puckers if you work
on this system, as the first coat of oil shrinks the fabric.
You will find that the second and third coats go on much
more easily than the first.

Oilskins, however, are not always suitable, and what
is known as "chemical" waterproofing, which scarcely
affects the appearance of the fabric, is preferred. This,
too, is easily executed. In principle it consists in filling
up the fibres of the cloth with a soap that will not dissolve
in water. You need to prepare two solutions. No. 1
is a solution of 1 lb. of best yellow soap in 1 gal. of water,
and No. 2. is, similarly, 1 lb. of alum in 1 gal. of water.
You can the more easily prepare the two solutions fairly
hot, but use No. 1 warm and No. 2 slightly warm. Put
the fabric in No. 1, and allow it to stay for at least half
an hour so that the soap gets on every particle of fibre.
Then remove it, wring it over the vessel, smooth it out,
and transfer to No. 2 (alum) solution for a second half-
hour's treatment. Again wring out the cloth, rinse it in
clean water, again wring out (or pass it between the rollers
of a wringer), and hang up to dry in the open air. That
is simple enough, but it is very effective.

269

MAKING DOVETAIL JOINTS IN WOOD

There can be no satisfaction of the boy mechanic's
ambition until he has tried his hand at a dovetail joint.
Now, the job is not so difficult as it looks, but for a start
make a fairly big joint in stout common wood. It ought
to be unnecessary to advise the reader to practise on

Fig. 1. — Half-lap Dovetail Joint

Fig, 2. — Single Dovetail Joint

model joints before attempting to dovetail together the
sides of a nice box or drawer, but is it ? When ambition
and skill run a race, which wins ?

Single Dovetails. — First let us make a "single"
dovetail — just such a joint as we might use in con-
structing framework. Both Fig. 1 and Fig. 2 are

270

Making Dovetail Joints in Wood

"single" dovetails, the former being generally given
the name of " half-lap dovetail." Bearing in mind the
method of making an ordinary half-lap joint {see p. 30),
this form of dovetail will prove easy enough.

You must not think that the wider you make the outer
end of the "tail" the stronger the joint will be. The
angle of the sides of the " tail " should not exceed about
15°, as shown in the diagram (Fig. 3). In very hard,

Fig. 3.— Diagram showing Dovetail Angle

Fig. 4.— Model Half-lap Dovetail Joint set out

tough stuff, the angle may be more, and in soft, weak wood,
as little as 10°.

The two parts of a lap dovetail joint are set out as in
Fig. 4. The square, gauge and bevel are the setting-aut
tools required.

But how is the blade of the bevel to be set to the
required inclination ? Take any planed-up piece of wood
and square a line a b (Fig. 5) across it, and divide the line;
into inches (or other uniform parts). Set off on the edge-
of the board to one side of the Hne a space of 1 in. (or
one part). On a narrow piece of stuff, make all the;

^7'

Every Boy His Own Mechanic

distances half-inches ; but the larger the unit the greater
the accuracy. Number the divisions on the line, say 1
to 5 or 6 (not shown in Fig. 5). Divide space 2-3 into two
parts, the space 3-4 into three parts, and number them
as indicated, respectively 2|, 3| and 3|. Place the sliding
bevel on the edge of the board with the blade right over
the 1-in. mark to the left of the line, and let its point reach
the 3^ mark on the line a b. Tighten the clamp of the
bevel; it will now be set at 15° to 16°, and with sufficient
accuracy for the purpose. Setting the blade to mark 5
gives an angle of approximately 12°, and to mark 2| an
angle of 20° to 22°.

Professional workmen use a little template for marking
out dovetails, and I think you will find its use makes for
ease and accuracy. You can easily cut one for yourself.
Set out a piece of tinplate as in Fig. 6. This can be any
length, but 4 in. or 5 in. will do admirably, and the width
may be 1 1 in., more or less. The dotted line shows where
it will be bent at right angles to the shape given in the
side view (Fig. 7). You will first have made up your mind
as to the angle to which the dovetails are to be cut, and
will then set out this angle from the end of the metal to
the shoulder line. The shaded parts are now to be cut out
with snips, strong heavy scissors, or with hammer and
chisel, finishing very carefully to the line with a file. The
method of cutting must depend upon the thickness of the
metal. After cutting, the piece will be bent as shown,
with a hammer, over the square edge of a board. Now
if this little template is put on the edge or end of the
pieces which are to be jointed, it will be a very simple
matter to scratch the correct outhne of the dovetail by

272

Making Dovetail Joints in Wood

means of an awl or the point of a knife. The template
will last a lifetime.

First we will cut the pin on the piece a (Fig. 1). The
shoulder of the joint must be set out with a square or
gauge on all four sides of the piece. Across the end grain
of the stuff gauge a line at half the thickness, and square
this line down on the edges to meet the shoulder lines
already set out. Put the stuff in the vice, and saw down
with the grain parallel with the face until you reach

Fig. 6

Fig. 5. — Obtaining Dovetail Angle
with Sliding Bevel

Fig. 7

Figs. 6 and 7.— Metal Template
before and after Bending

the shoulder lines. You must next remove a half thick-
ness of stuff, so on that face opposite to the one where
the ^ dovetail is to be, cut in with a saw to half the
thickness, so as to detach a piece of wood. Next with a
saw cut in on the shoulder lines on the edges until you
reach the slant Hnes that define the sides of the pin.
Then put the work, slightly inclined, into the vice, and
remove the waste chip by chip with the chisel, the handle
being held in one hand, and the lower part of the blade
between the thumb and first finger of the other.
s 273

Every Boy His Own Mechanic

For the setting out of the socket piece b (Fig. 1),
either the bevel or the little template can be used, the
lines being squared down on the two edges to meet a

horizontal line at half the
thickness, which will be
obtained by means of the
gauge. The waste will
be removed by sawing
down on the slanting
lines and then with the
chisel taking out the stuff
chip by chip, as explained
on page 273. A more accurate method of setting out the
socket piece is to use the pin already worked as the
template or pattern, laying it on the second piece of
wood and marking the outline of the socket by means of

Fig. 8.— Scribing Socket from Half-
lap Dovetail

Fig. 10.— Scribing Pin

from Socket of Single

Dovetail

Fig, 9. — Single Dovetail Set Out, and
the Socket Sawn and Worked

awl or knife, taking care afterwards to saw down to these
lines in the waste, the reason for which precaution I have
already remarked on in an earlier chapter {see Fig. 8).

274

Making Dovetail Joints in Wood

The form of single dovetail shown in Fig. 2 is excellent
for framework. In this case it is better to cut the socket
first and to mark out the pin from this. As before, you
need to see that the shoulder line is squared on all four
faces (Fig. 9), while the slant lines across the end must be
set out by means of bevel or template ; lines connecting
these slant lines to the shoulder lines on face and back of
stuff are then drawn by
means of square and pencil.
Put the work vertically in a
vice, saw down on the slant
lines, and remove the waste
with a chisel as usual.
Place the socket piece on
the other member of the
joint to form a right angle,
and with a slender awl
scribe the shape of the pin
on the work as shown in
Fig. 10. Square the shoulder
lines and also the lines
across the end, then saw
down outside the slant lines, and cut in from the side
so as to detach the two small pieces.

Often it is possible to save a great deal of time in
cutting out a large dovetail socket by using a bow-saw,
as in Fig. 11, cleaning out the socket by means of a chisel.
The bottom of the socket is finished with the chisel held
bevel outwards, the work being laid on the bench with the
narrower part of the socket uppermost — a most important
point.

275

Fig. 11.— Sawing Out Waste of
Large Single Dovetail

Every Boy His Own Mechanic

The Box Dovetail. — There is a great variety of

dovetailed joints, but I propose to explain only one more,

and that is the box or com-
mon dovetail (Fig. 12). For
a start, do not attempt to
make a very fine joint, but
work in common wood, and
make the angle of the dove-
tail slight. As in all joint
making, the setting out is of
the greatest importance, and
this setting out can only be
properly done after the wood
has been carefully planed up
smooth and parallel, and the
edges have been shot true.
I have already explained

what " shooting " is. The work is held in a shooting

board over which its edge very slightly projects, and a

keen plane is then " shot " along to take off a very fine

shaving or two from the

end grain.

Shoulder lines must

now be squared or

gauged round (see Fig.

13) on both pieces,

and, as in all joints of

this simple kind, these

lines will be distant from the ends of the stuff by

an amount exactly equal to the thickness of the stuff.

In the first place, it is easy to get confused as to which

276

i^ Fig. 12. — Common or Box
Dovetail Joint

Fig, 13. — Gauging Shoulder Line for
Dovetail Joint

Making Dovetail Joints in Wood

Fig. 14. — Spacing Dovetail Pins with
Dividers

piece carries the pins and which piece contains the
sockets, because, as a matter of fact, there are pins and
sockets on each of them ; but in the joint shown by

Fig. 15 the part that
carries the four thin
projections has the
" pins " whilst in the
other are two com-
plete sockets and
two half - sockets.
Woodworkers do not
agree among them-
selves as to whether
the pins or the sockets should be cut first, but I am
going to describe the " pin first " method, and I think
you will find it quite satisfactory.

We will have chosen two pieces of board in which
two complete pins and two end
pins can be cut, as in the illus-
tration (Fig. 15). The shoulder
lines have been squared round.
At the extreme ends mark off
on the face from each edge half
the thickness of the thinnest
part of a pin. This " thinnest
part" is shown on the edge of the
socket piece, and its dimension
varies with the thickness of the stuff that is being joined
up. For wood up to f in. thick, the thinnest part of the
pins may be I in. thick, but don't aim at too fine work
at the start. With dividers or compasses {see Fig. 14)

277

Fig. 15. — Common or Box
Dovetail Joint

Every Boy His Own Mechanic

divide the space between the two points already marked
on the shoulder line into three, and set off on each side of
these marks half the thickness of the pin. Set off that
distance also inside the two end marks
already made. Next, with a small try-
square and an awl, draw
lines from the shoulder line
to the end of the work to
indicate the sides of the
pins {see Fig. 16).

The slant of the dove-
tails will now need to be in-
dicated on the end grain of
the piece, for which purpose
you must fix the wood vertically in a vice, and by means of
a bevel or template {see Figs. 17 and 18) mark the ends of
the pins across the end grain, continuing the work by means
of the square on the back of the work so as to draw the sides

Fig. ^6. — Squaring Down Dovetail
Pins

Fig. 17. — Marking Ends of Dovetail
Pins from Sliding Bevel

Fig. 18.— Marking Ends of

Dovetail Pins from

Template

of the pins as far as the shoulder line. The little template
illustrated can easily be made by the boy mechanic in
wood, or, as already explained, in metal, or it can be
bought ready made.

278

Making Dovetail Joints in Wood

Keeping the wood fixed vertically in the bench vice,
cut down with a fine saw on the slant lines which cross
the end grain, but see that the saw cuts keep accurately
to the parallel lines that have been squared down from
the end to the shoulder lines. A chisel is used for cutting
out the waste, but, by the way, first make sure which is
the waste, and to prevent mistakes it is better after setting
out to mark with a pencil cross any stuff that is to be
removed, as otherwise an accident or mistake is the easiest

Fig. 19. — Scribing Dovetail
Sockets from Pins

Fig. 20. — Squaring Ends of
Dovetail Sockets

thing possible. Your best plan will be to use a fine carving
chisel, particularly if the work is rather small. Clean out
the recesses between the pins, and do everything you can
to produce sharp, true edges, and a perfectly flat bottom
to each of the recesses. Of course, each recess is really a
socket, but if I label them "sockets," you may easily
become confused between the pin piece and the socket
piece.

This box dovetail is really, as by this time you will
have discovered for yourself, a number of single dovetails

279

Every Boy His Own Mechanic

cut side by side in the same piece of wood, and you will
therefore be prepared to understand that the socket piece
is set out by " scribing " — that is, the pin piece is laid on
the other member of the joint (on which the shoulder lines
have already been squared), and a slender pointed awl is
used as in Fig. 19, to " scribe " the shapes of the sockets
from the pins.

As all you have so far marked on the socket piece is
the shoulder line and the slant lines on one face, you will
need to use a square (Fig. 20), and continue the socket
lines across the edge of the stuff. The sockets are cut
out in exactly the same way as the pins were formed,
having previously taken the trouble to mark with a cross
the parts that are to be removed.

280

TURNING METAL IN THE LATHE
By a. Millward

With the lathe as described in the chapter on wood
turning it is quite possible to do a limited amount of
metal turning of a light and simple character. For in-
stance, it may be desired to turn a small knob or handle
in brass, or turn a small rod or spindle, or do a number of
small jobs as necessity arises ; and these are quite pos-
sible in the lathe shown on p. 220.

Metal - turning Tools.— These have quite different
cutting edges from those of wood-turning tools, due to

Fig. 1. — Metal-turning Graver

the difference in hardness and character of the material to
be turned. Since the lathe is only adapted for very light
metal turning it will be better to confine the attempts
to turning in brass, and for this purpose a single tool, a
"graver," will probably be all that is required. This
{see Fig. 1) comprises a bar of square steel sharpened
at an angle so as to produce a diamond-shaped point ;
the face of the tool must be kept perfectly fiat, and
the tool must be kept well sharpened by grinding the
flat face only.

281

Every Boy His Own Mechanic

Rest and Chucks. — A metal-turning rest is usually
flatter on its face and of a greater width but of a less
length than one used for wood turning so as to provide a
greater width of bearing surface for the tool.

A " chuck " of some kind for holding the metal is a
necessity for any work that cannot be held and turned
between centres. A " self-centring chuck " will save
much time if round or circular work is to be turned.
Such a chuck comprises three radially arranged jaws,
which can be moved equally towards or away from the
centre, and between which the work is gripped. For
holding irregular work a chuck having independently
movable jaws will be required.

A Simple Metai-turning Job. — In order to turn a
bar or spindle between centres proceed as follows : —
Having obtained a bar of a suitable length, first square
or file the ends so that they are at a right angle to its
length. Now find the centre, that is the axial centre, of
the bar by marking intersecting lines on its ends. A
convenient way of doing this is to mark two lines at an
angle to each other by means of a centre square, a little
tool somewhat resembling a T-square but having, in
some types, two pins in the head of the squares ; the edge
of its blade intersects at right angles a line connecting
the two pins. Another method is to set a pair of dividers
to approximately half the diameter and to scribe a series
of lines by resting one leg of the dividers on the edge or
circumference whilst the other one is used for marking
the end face ; finally the centre between the marks
must be judged. Mark the centres when found with a
centre punch, and then, on each end, drill a small hole

282

Turning Metal in the Lathe

about I in. deep. Now take the centre punch, which
should be sharpened to the same angle as the lathe centres
(usually 60 deg.), put the point in the hole and hit it
smartly until a coned-shaped hole results, which forms a
bearing for the lathe centres when the bar is placed
between them.

It is now necessary to pro-
vide means to cause the bar to
rotate with the rotating man-
drel of the fixed headstock.
For this purpose a "carrier"
is used. A simple form of
carrier is shown in Fig. 2;
the rod a is inserted in the ^
hole b, and the carrier gripped
to the rod by screwing up the
screw c. The carrier is so fixed
on the rod that the end d
comes into contact with a
pin or driver secured on the
face-plate.

The graver is now held
firmly on the rest, which is so
adjusted in height that the
point of the tool can be held
so that it is in line with the axial centre of the Avork ;
the position will be quickly found by experiment, as the
tool will not cut properly unless the correct position is
found. The tool must only be moved towards the work
very gradually so as to remove quite a small amount of
metal at a time. When the desired diameter is reached

283

Fig. 2. - Metal-turner's Lathe
Dog or Carrier

Every Boy His Own Mechanic

the tool is turned over so as to present one of the sides of
the diamond-shaped face to the work, which will remove
the irregularities produced by the point of the tool. With
a little practice a perfectly bright and smooth surface
can be obtained which will not require any further finish-
ing. By altering the angle or position of the " graver "
tool it will be found possible to produce rounded surfaces,
V-shaped grooves, square recesses or shoulders, but it
will not be possible to produce rounded hollows with it,
for which purpose a rounded hollow-nose tool will be
necessary.

9B4

FRETWORK IN METAL AND IVORY

Equipment. — Saw-piercing in metal is a higher stage
of the fret-cutter's art. It requires special saw-blades
having very much finer teeth — so fine that the unaided
eye can scarcely see them. A suitable
grade is No. 00, and only the highest
quality with rounded-backs should be
bought. The woodworker's fretsaw
frame can be used if desired, but a
smaller frame is more suitable. The
type shown in Fig. 1 has the advan-
tage that the handle part slides along
the back when the thumbscrew is
loosened, thus allowing of broken pieces
of saw - blade being accommodated.
Fig. 2 compares fretsaw blades for
wood and metal.

Ordinary paste does not
adhere very well to metal,
and it is better to use a
mixture of starch, gum
arable, and sugar. The
gum arable can be bought at any oilshop. One ounce of
it placed in a piece of muslin and soaked for a few
hours in water and then turned out into a jam-jar

285

Fig.l.-

Metal

Fretsaw

Piercing

Saw

Fig. 2. — Metal and
Wood Fretsaw
Blades

Every Boy His Own Mechanic

containing 1 oz. of starch and 4 oz. of sugar with about
I pint of water will make a good paste for the purpose,
the mixture being boiled until it thickens.

Applying the Design. — Let us take a useful little
pattern like Fig. 3, a design for a large brooch. Make a
tracing of the design on thin paper, and, using only just
paste enough, stick it down on the metal. (To get a pair
of patterns when the design is reversible, make two tracings
on very thin translucent paper, and in pasting them
down see that one of them is reversed so that its face is
in contact with the metal.) Allow to dry thoroughly

before proceeding further.
When the fretting is com-
I>1 pleted, the remains of the
paper will need to be soaked
off in hot water.

Professionals frequently
adopt a different method of
transferring the design. They
use carbon paper and a

Fig. 3.

-Design for Large Brocch ^ard point for transferring it

or Waistbelt Clasp ^ °

to the metal and then, while
the lines are fresh, go over them with a steel point, which
gives them an indelible nature. Metal that has been
smeared with gamboge (a lump can be bought at a
chemist's for a trifle, and most colour-boxes include it)
and allowed to dry can be drawn on with an ordinary
pencil.

The "pouncing" method is useful in transferring all
kinds of designs for all sorts of purposes. The pattern
or a tracing of it is converted into a stencil by pricking

286

Fretwork in Metal and Ivory

over its lines with a fine piercer, awl or needle ; the coarser
the pattern, the wider may the holes be spaced. The
stencil is laid down on the metal and rubbed over with a
little muslin bag containing fine chalk, the pattern then
appearing in dotted lines on the metal, and being easily
made permanent by going over them with a fine pen or
hair pencil and brunswick black thinned with turpentine,
or by scratching over them with a steel point. The
stencU can be used scores of times, and the method could
be employed for wood fretwork, using, instead of the black,
a very dilute mixture of Chinese white and water, and
applying it in such thin lines that the saw would utterly
obHterate them.

Using the Saw on Meta!. — The saw should be
worked much more slowly and deliberately on metal
than on wood, very little pressure should be apphed, and
the point of cutting should be kept supplied with oil or
with turpentine, which, together with an occasional rub
of the saw on a piece of beeswax, will make a big differ-
ence to the ease and speed of working. The blade soon
gets hot with the friction, and must be given a few
moments to cool before proceeding. As before, holes
must be drilled to take the blade, for which purpose the
Archimedean drill stock AviU come in handy again, but the
boring-bit used on wood will not be suitable, and in its
place you must get a tiny twist-drill, and keep it lubri-
cated with turpentine, bearing in mind that it is not
strong enough to stand much pressure. An alternative
method is to prick through with a fine piercer or awl,
first placing the metal on a block of hard wood.

Beautiful fretwork can be done in copper, brass,

287

Every Boy His Own Mechanic

aluminium, ivory, ebonite, and, of course, gold and silver ;
when working in the precious metals there should be a bag
of leather or waterproof material underneath the bench
to catch the waste, as this has market value. Silver
works out fairly expensively, but for occasional articles,
such as pendants, ladies' ornaments, etc., it may be
used of No. 23 gauge metal (standard wire gauge), which
is -024 in. thick, and equivalent to about 9 sq. in. to the
ounce — enough for, say, two club badges, or for five
hatpin heads or charms.

The saw cannot do the whole of the work, and you
will soon find that much of the delicate detail must be
executed with tiny files, of which two or three selected
shapes, including a needle file, should be bought. Files,
also, must be used for correcting outlines. A triangular
file is best for the sharp angles.

Finishing. — The cutting having been completed, the
paper pattern (if used) must be removed with hot water,
and the metal laid upon a block of wood or lead and
worked over with fine pumice powder and water rubbed
vigorously with a large smooth cork. This will remove
any swarf at the cut edges and prepare the piece for
polishing, which is a matter of time and patience, and is
done with a soft leather and tripoli powder and oil, finishing
in the same way with jewellers' rouge appHed dry.

288

BUILDING A DOG KENNEL

In this chapter I am giving you drawings for a big kennel.
Some of you may think it is far too large, inasmuch as it
is 4 ft. long by 3 ft. wide, but I am taking a rather big
construction because, as a matter of fact, the actua
making is easier in the case of a large kennel than with a
small one, and there is no reason whatever why you
should not build, from the instructions and drawings
here given, a much smaller house should you so wish.
For example, if you reduce length and breadth to 2 ft.

Fig. 1. — Dog Kennel Solidly Built in Sections
T 289

Every Boy His Own Mechanic

Fig. 2. — Front Elevation of Kennel

and packed flat,
while the construc-
tion is very solid
and good enough for
a lifetime's use.

You must study
the drawings before
you cut a single
piece of timber, so
as to realise fully
what you propose to
do. There are seven
main pieces in the
construction : the
floor, four sides, and
two roof pieceSj^and

and 1 ft. 6 in. respec-
tively, you get a very
nice size kennel for a
small terrier, and the
drawings will still answer
exactly as before, except
that the bearers and
ledges need not be so
thick as shown in the
illustrations. There are
some excellent points
about the kennel here
shown, not the least of
which is that it can be
readily taken to pieces

Fig. 3. — Longitudinal Section through
Kennel

290

Building a Dog Kennel

each of these is built up as a separate unit. You will notice
in the illustrations that a number of bolts and nuts are
shown. I advocate these if there is any chance that the
kennel may not be required for some time, or if it is to be
made in one place and transported to another ; but there is
not the slightest reason why you should not use 2|-in.
or 3-in. brads or nails (to be clenched over) or 2|-in.
screws if you so prefer.

i^)j M)i>}n>>jj,AM ^^>^^ff}}JWPJ

! G

THZn^

^jSBSm

Fig. 4. — End Elevation of Kennel

Fig. 5. — Horizontal Section
through Kennel

You will realise that the principle of construction is
first of all to build up the seven main pieces accurately to
size, and then bolt or nail them together. This is a much
better plan than building up the kennel as a whole, board
by board, and it is a method which you will find always
answers best in any work of this kind — poultry houses,
beehives, summerhouses, and so on. All portable
constructions are bcs>t built in sections, as here shown.

291

Every Boy His Own Mechanic

You can make a start with the four sides, or rather
with the front, end, and two sides. All the boards consist
of grooved and tongued stuff 6 in. wide and preferably
1 in. thick, but slightly thinner if you like ; | in. stuff
would do for a small kennel. See that the boarding is
planed up and fits well together before it leaves the timber
yard (if you are buying it locally). You can take all the
dimensions from the drawings, which, except the general
view, Fig. 1, are to a
scale of I in. = 1 ft.
Fig. 2 is the front ele-
vation, Fig. 8 the
vertical section length-
ways of the kennel.
Fig. 4 the end eleva-
tion, and Fig. 5 a plan
or section through the
body of the kennel.

As here shown,
the sides are 3 ft. 1^ in. high, but, of course, you are
at liberty to vary this by an inch or two as you
think proper. Eight widths will be required, and
they will be nailed top and bottom to two bearers or
ledges,. A and b; the top one a is 2 in. deep and 1| in.
thick, and the bottom one b. 3 in. deep and 1| in. thick.
These bearers or ledges will come flush with the top and
bottom edges of the boards. At the ends you will nail
fillets or angle pieces g, which need to be about 1| in.
square, and the construction when this has been done will
resemble Fig. 6, which shows the inside view of one of the
sides. It will be necessary to saw off the extreme ends of

292

Fig. 6. — Internal View of Side of Kennel

Building a Dog Kennel

the fillets or angle pieces to accommodate the top and
bottom ledges, as shown in Fig. 6. Both of the sides of
the kennel will be the same.

Now for the front and end. All the materials will be
of the same thicknesses, etc., as for the sides, and the
pieces will be built up by means of two bearers or ledges
as before, as shown at c and D. The front and end are
3 ft. 1| in. high to the top of the sides and about 4 ft. 8 in.
high to the apex of the angle or gable. Fig. 7 is the inside
view of the front or end, showing the positions of the
bearers, and it will be noted that these are cut away at
the ends to allow for the ledges a on the sides when the
four main pieces come together.

The entrance hole in the front can now be cut. In the
illustrations it is assumed to be about 1 ft. 9 in. wide, and
about 2 ft. 8 in. high from the ground level, but this will,
of course, depend upon the size of the dog, and whether
you are working to the dimensions here given or to a much
smaller scale. Set out the opening centrally with square,
rule, compass, and pencil. Saw down with a hand saw as
far as you can, but don't saw through the bearer d
(Fig. 2), and finish with a turn or compass saw. Smooth
the edges with glasspaper held on a block of wood,
using, if possible, a curved block for the glasspapering
at the head of the opening. It would strengthen the
front if an extra fillet were nailed across (on the inside)
under c (Fig. 2), and just over the opening, before
cutting.

We can now consider the floor of the kennel. As
drawn, it is about 2 ft. 10 in. wide with an extreme length
of 4 ft. It will be built up of about the same sort of

293

Every Boy His Own Mechanic

material as was used for the sides, and nailed to two
ledges as shown in section at f in Fig. 3, and also in the
general view of the floor shown in Fig. 8. In Figs. 5 and
8, you will note that square notches will have to be made
to clear the fillets or angle pieces, and, in addition, the
front end of the floor is cut away at the sides so that the
centre part projects a trifle past the opening.

We have now to make the two parts of the roof. They
will each consist of five widths of 6 in. wide material, of
the same thickness as used elsewhere ; but one part of the
roof will be narrower than the other by an amount equal
to the thickness of the stuff used. If you study the front
elevation (Fig. 2) you will easily see why. One part of
the roof overlaps the other, and if they were of exactly
the same width, the eaves at one side would be lower than
on the other ; so if you are using | in. material, saw off a
strip I in. wide, and you can probably do this more easily
from the completed roof part. The bearers or ledges
can be of the same material as the bottom ledges of the
sides, that is, 3 in. by 1| in., and it is better to have three
bearers for each roof part. You will, of course, note that
the roof boarding is longer than the side of the kennel.
A length of about 4 ft. 8 in. will give an overhang at each
end of about 4 in., and this is advisable inasmuch as it
helps to throw off the rain, keeps the dog more comfort-
able, and preserves the kennel from decay. You need
to be very careful in deciding the positions of the end
roof bearers, as these must, of course, just clear the
inner surfaces of the front and end of the kennel.
Study Fig. 3, and this point will be obvious.

We have now the seven main pieces, and before we do

294

Building a Dog Kennel

anything more we might as well give them all, except the
floor, a couple of coats of paint or good outside varnish,
but do not paint the inside. A coat of brown or green
stain before applying the varnish is not a bad idea.

Let us set about assembling the kennel. We need a
good flat, clean floor, or a flat bench top or table
top upon which to work. Prop up one of the sides,

"^^

Fig. 7. — Internal View of End
or Back of Kennel

Fig. 8. — Underneath View of
Floor of Kennel

and put the end in position against it. Having
settled whether you are going to use bolts or screws,
the latter being much the easier, it will be necessary
in the case of bolts to bore holes from the end right
through the angle piece, as fully explained in the detail
sectional view (Fig. 9), which shows a section taken
on the line h in Fig. 2 ; on the right is one of the
sides to which g is nailed, and at the bottom is either
the front or the end, to which g is bolted. One little

295

Every Boy His Own Mechanic

point : You will notice that in this section the extreme
corner of the angle piece has been trimmed off, with the
object of not leaving any hard corhers for our friend the
dog to knock himself against. Having secured the end,
place the second side in position and proceed as before,
taking great care that all the joints are square, and that
there is no tendency for the rectangular construction to
go out of shape as indicated by the dotted lines in Fig. 10.

Fig. 9.— Details of Corner

Joint of Kennel, showing

Bolt and Nut

Fig. 10. — Diagram showing
Tendency for a Square Con-
struction to go out of shape

Now let us put the floor in. It will easily go into the
three-sided box already formed if it is slanted a trifle.
There is no real need to nail it down to the bearers, but
you can please yourself.

The front can now be added, and all will be ready to
receive the roof. Get someone to help you to hold
the two parts of the roof in something like their proper
positions. You will find that some little adjustment
with the plane will probably be necessary on the top
edges of the sides, so that the roof boards " sit " well in
place. The roof bearers are secured to the front and ends
with bolts or screws, exactly as before. You will need

296

Building a Dog Kennel

altogether eight bolts at each end of the kennel or a
dozen screws.

All the woodwork is now completed, but the construc-
tion would not be watertight if left in its present state,
and it is advisable to get some good-quality tarred felt
with which to finish the roof, allowing the felt to project
all round for about f in. A big kennel like this will of,
course, be kept in a yard or garden, and so must be very
well protected with paint or varnish against the weather.

297

LAYING THE RAILS FOR A MODEL
RAILWAY

By Henry Greenly

The author's practical experience in this direction dates
from the time when an ingenious and skilful friend made
him a wooden model locomotive which had flanged wheels

for running in the orthodox

■flange- ^1

N?0

_2.
64

read

IN? I

,iX"

I 32.

V-'i'--- -X

N?2

3 »

7. .
60-

Fig. 1. — Standard Gauges and
Wheel Dimensions (Indoor
Model Railways)

manner on rails. At the
outset the locomotive ran
by force of gravity, but later
it was improved by the
addition of an "elastic"
drive such as that now com-
monly adopted for model
aeroplanes. Clockwork
motors and electric
mechanisms had yet to
make their advent for
model locomotive work.

The rails were hard
wood strips of about | in.
by I in. rectangular section
glued and pinned down to
a baseboard. The points
were fashioned with a pen-
knife, and were pivoted at
298

Laying Rails for a Model Railway

the heel with a fine cabinet-maker's brad. This crudt
affair, however, was sufficient to make clear the importance
of accuracy in the matter of rail gauge and wheel widths.
The " between-tyre dimension" is of the utmost import-
ance in any railway, real or model. The London, Brighton
and South Coast Railway suffered a bad accident at
Stoat's Nest, due to the wheels of a carriage spreading
out. Miniature " Stoat's Nests' " will happen continually
on a model railway unless the work in these particulars
is done Math a reasonable degree of accuracy.

POl r-<T RODD'NG

Fig. 2. — Diagram showing Railway Points with all the Parts Named

Fig. 1 shows the standard dimensions for the three
smaller model railway gauges, Nos. 0, 1, and 2. It will
be noticed that almost the "same width of tyre is
adopted for all three sizes. This is because the minimum
it is practicable to adopt is reached on the No. 1 gauge.
The No. 0 gauge cannot be reduced, as the same size rails,
etc., are common to both sizes.

Fig. 2 will enable the boy mechanic to identify the
essential parts of a standard British arrangement of rails
and points. The chairs and sleepers are omitted ; in
model work the arrangement of these will depend on the
material available.

The question of material for rails will naturally

299

Ai — Hard wood rail
nailed to base-
board : suitable
for cardboard or
wooden engines

B. — Square iron
rail, screwed
to sleepers or
baseboard; for
indoor or out-
door lines

D. — Umbrella ribs
nailed to base-
board ; nail holes
drilled or notched
with S-corner file,

E, — Angle iron
screw ed or
nailed down.
T-iron inverted
may be used in
the same way

C. — Strip iron rails driven
into slots ' in heavy-
section sleepers

F. — Tinplate rail
and sleepers as
used for clock-
work railways

G. — Hollow tin or
brass rail in
pressed sheet
slide-on chairs

H. — Similar arrange-
ment to G, but solid
steel rail and spring
sheet steel chairs
which slide on ;
sometimes cast
typemetal chairs of
similar design are
used

J. — Standard British keyed
chair system ; brass or
steel rail, cast typemetal
chairs, wooden keys out-
side the rails. The best,
but most expensive, track

K.— Flat - bottomed
solid rail (Ameri-
can style), dog-
spiked or screwed
down with dog-
washer (both are
shown) ; not gener-
ally made in small
sizes

Fig. 3. — Various Systems of Railjt Formation

Laying Rails for a Model Railway

arise very early. There are innumerable arrange-
ments from which a choice may be made, and
therefore a table is given on p. 300 of a selection of
various kinds of rail material ; the latent sources of

Fig. 6.— Solid Rustless Steel
Rail and Pressed Chair

Fig. 5.— Pressed Metal Chair
for Hollow or Solid Rails

Fig.4.— Tinplate or Sheet Brass Rail

supply are, however, not ex-
hausted by this list.

For an indoor line of If in.
(No. 1) gauge, such as would
be suitable for the model ex-
press engine described in an
earlier chapter, the hollow
tin or brass rail illustrated
at G in Fig. 3 may well be
chosen. It is the cheapest of
what may be considered the
proper thing, whilst the next
best is the system using a solid
steel rail, as shown in h (Figs. 3 and 6), with similar chairs.

An indoor railway requires some more or less per-
manent baseboard. The average system is laid down on
what are virtually shelves round the walls of the attic or

301

Fig. 6a. — Model Spring Fish-
plate for Solid Rails
H and J (Fig. 3)

Every Boy His Own Mechanic

spare room devoted to the railway. The baseboards
may, of course, be quite separate from the walls, and
may be arranged in sections placed on trestles when it is
required to use the line : normally, the sections are
stacked away. However they are built up the base-
boards should be level. Wooden sleepers may be laid
down previous to putting on the rails and chairs, these
sleepers being set out in accordance with and to suit the
proposed line of railway. The baseboard should be

ChecKrfliI c^^idcs ivhce/

ChecK (rail norcjutaina wheel

Fig. 7. — No Control over
Direction of Wheel if
Check Rail is Absent or
Misplaced

lotje clears

Fig. 8.— Wheel Controlled or
Guided by Check Rail in
the proper way

marked out with four lines besides the centre line of the
track, two outer lines indicating the edges of the sleepers,
while the inner lines show the inside edges of the rails.

Sleepers should, of course, be made of equal thickness,
as otherwise the track will not be level. They can be
stained black, with ebony stain, Stockholm tar, or similar
colour or preservative, to make them look like the real
thing. They should be spiked down exactly under the
centre of the rail, so that the spikes which hold down the
chairs do not interfere. The scheme is shown in g to k
(Fig. 3).

One of the photographic plates shows the general

302

Laying Rails for a Model Railway

arrangement of the " frog ," portions of a pair of points
made up in a chaired road. The frog, as indicated in
Fig. 2 in this chapter, is that portion of the points where
the one rail crosses the other, and the peculiar arrange-
ment is necessary to allow the flange of the wheel to cross
over another line of rail and at the same time to provide
a continuous bearing for the tread of the wheel. Ob-
viously the flange could not be expected to jump up

-BT_

£1

ii_

Fig. 9. — Check
and Wing Rail
dimensions:
BT, between
tyres (sse Fig.
1) ; G, gauge
of rails ; S,
space between
check and
running rails ;
CW, check to
wing rail
dimension (^"
less than BT)

[ — Line of roils

'j, — Line of Sleepers

Fig, 10

Pencil

Trammel Beam •>

"1?"

r?i

rn.

90°

Rvot Poinl-

Fig. 11

Figs. 10 and 11, — Setting out Curves and Points
with Trammels

over a rail, and while the rail is broken the guiding effect
of the flange is preserved by the system of wing and
check rails, clearly illustrated in Fig. 2

Figs. 7 and 8 show the necessity of properly fitting up
the wins and check rails. In the first sketch it is evident
that a wheel will just as easily travel along the line of
track if the check rail is either absent or is laid down

303

Every Boy His Own Mechanic

with too great a space between it and the stock rail oppo-
site the frog Where the check rail and wheels are correctly
proportioned and properly fitted, the check rail acting
on the opposite wheel to that traversing the frog retains
the latter wheel in the straight and correct path. In all
the small gauges the distance between the main and the
check and wing rails is settled by the all-important " be-
tween tyre dimensions," as shown in Fig. 9. The distance
over check and wing rails, c w, should be y^th of an in,
less in all the three small gauges (Nos. 0, 1 and 2) than
the " between-tyre " dimensions given on the diagrams in

Lorqc radius
u-fiecfi

1 — z:r-=r.

^ \

AS SET OUT \

ddiAOii of

Fig. 12.— Setting out Rails
from Straight to Curve

Fig. 13.— Sketch of " Rail-
gauge " for Model Railway
Work

Fig. 1 (1 in., 1|| in., and Iff in. each gauge respec-
tively). The space s (Fig. 2) is therefore half the difference
between the dimension c w and the gauge g.

In setting out ciu'ves and points the use of the
" trammel " is strongly recommended. A very simple
instrument of this kind is shown in Fig. 10. The centre
point may be a stout needle or other stiff steel pivot, and
to allow for scribing out the four lines (two for the rails
and two for the edges of the sleepers) the pivot end of the
wooden lath forming the trammel may be provided with

304

C/2

I— I

W
Q
O

» IHT-'I IT.]

■*'■ ,1!F^

Laying Rails for a Model Railway

four holes for the pivot pin, each hole corresponding to
the radius to be drawn. In setting out points (Fig. 11)
the pivot point at which the trammel swings should be
at exactly 90 deg. to the toe of the points (that is, the toe
of the switch rail). In the case of ordinary curves which
enter straight portions the best scheme is to provide a
transitional entrance to the curve. In this case the curve
is set out with the trammels as shown in Fig. 12, not

exactly at a tangent, -Clir^-^^rr-—

and the junction ^- • - — -^ -

between the curve

made with a larger

radius curve which

can best be judged

by eye.

A " rail-gauge "

made as shown in

Fig. 13 is a simple ^:=::::OsC;;^--„^ z^'-

device for setting ^^''^^^^''^jC:;:

the rails true to fc

gauge. It may be . „„

X Fig. 14.— How to Lay Frogs : A, Wmg

made out of sheet rail space inaccurate ; B, Rails not in

, -, , , , . continuous line ; C, Correct Spaces

metal, tne strips ^g^^ l^ajl Ung continuous {see dotted

being driven into ^*°® ^ ^^

saw cuts in a block of wood, or soldered to a metal

base plate.

In laying plain rails one rail should be put down
first, tuned up by eye, and then the adjacent rails laid to
suit, using the " rail gauge " instrument already described.
Much -)f the final accuracy of the track is obtainable by
sighting along the rail. Surface "wind" or "twist"
u 305

Every Boy His Own Mechanic

may also be observed by looking across from rail to rail
with the eye on a level with the top face of the rail.

When laying down points the lining up of the frogs is
an important feature. The diagrams a and b (Fig. 14)
are examples of " how not to do it." The inner edges of
the running rails should line up accurately so that by a
straightedge, or by the eye, it can be observed that the
line of the inner edge, against which the flange runs, is
continuous, just as though there were no frog there at all.
This is shown at c (Fig. 14).

Very much more could be said on this subject, but
the variety of materials available is large and the minor
features of each create special difficulties and conditions.
The broad principle has, however, been covered, and is
unalterable whatever kind of track material is used.

306

BUILDING A 10-FT. FLAT-BOTTOMED
ROWING BOAT

There are boats and boats, and most of them are beyond
the capabilities of the young woodworker. I know,
however, what a fascination the building of a knockabout
boat has for boys young and old, and I therefore feel
obliged to include a chapter giving drawings and instruc-
tion on making a boat of a type within the scope of any-
body at all handy with woodworking tools. The details
of the design here presented are due to Mr. D. Kidd.

Fig. 1 is the sheer draught or elevation of the boat,
Fig. 2 is the half-breadth plan, while Fig. 3 is a section
" amidships," that is, it is a section right across the centre
of the boat. This is an excellent knockabout boat for
lakes and rather sluggish rivers, being of comparatively
light weight, very stable, and, owing to its design, not
dragging water. It tows easily, can carry a big load, and
does not require a professional boat-builder to construct
it ; but like all flat-bottomed boats it is apt to pound in
choppy water.

It must be realised that this is a small boat — 10 ft.
by about 4 ft. — and that any load it carries needs to be
distributed properly. One person alone would occupy
the central seat. Two people would have an end seat each ;

307

Building a Rowing Boat

three would be distributed over the three seats, while,
when there are four people, two would be on the centre
seat and one at each end, one of the latter doing the
rowing. Keeping to this rule will mean an even keel.

You may care to know that the design has been adapted
from that of the American fisherman's dory, the system
of construction being practically identical. Briefly, the
side planks are secured to a stem or stempost at each end,
the inner upright tim-
bers added, and the
bottom then put on.

The first thing to
do is to prepare the
" moulds." As long
as they are strong and
of the right shape and
dimensions it matters
not how they are made
up. Two " quarter
moulds," as Fig. 4,
and one " amidship
mould," as Fig. 5, will
be required ; each of
these is 18 in. high,
and the former is 38 J
in. wide at the top,
tapering to 30 in. at
the bottom, while the
latter is 47 in. and 38|
in. respectively. As
illustrated, they are

.2*

•a

'a
<

Every Boy His Own Mechanic

Fig. 4.

-30 i

-Quarter Mould

built up of thick rough stuff 6 in. wide, well nailed at
the joints, so that any " giving " at those parts is im-
possible. A notch 1 in. by f in. is cut out at each
bottom corner {see dotted lines).

The stem or stempost at each end of the boat is the
only detail that will tax the skill of the woodworker.
You know that the stem is the upright or nearly upright

piece at the sharp end
-* of a boat, into which
the planks are secured,
and as, in this case,
both of the ends are
sharp, two such pieces
will be required. They
are about 22 in. long,
and after the bottom
planking is on they
will need to be sawn
exactly to size. The
section through the
stem or stempost is as
shown in Fig. 6, which
is very fully dimensioned. Probably you can get a joiner to
supply you with a piece of oak, mahogany or other hard
wood (softer stuff is useless) cut to the section shown, as
it will be a rather awkward job to produce such a section
at home ; but if there is no alternative I suggest that the
best method of going to work is to get a piece of stuff 3 in.
square and 22 in. long, and make in it a series of cuts
with a tenon saw or dovetail saw, as indicated by the
dotted lines in Fig. 7. This will have the effect of pro-

310

k 28%"-

Fig. 5. — Amidship Mould

Fig. 6. — Section through Stempiece or
Stempost and Sides

Building a Rowing Boat

ducing a piece of the section shown in the hatched Hnes.
and you will then need to divide this into two with a
hand saw on the dash-and-dot line shown. Afterwards
clean up with
glasspaper. Now,
I don't recom-
mend this job. It
requires a great
deal of care, pa-
tience and skill,
and I think that
if you can get the
stuff cut for you so
much the better.
The side plank-
ing is only | in.
thick, and should
be of good qual-
ity. This thin
stuff will readily
bend to the shape
required. Four
planks will be re-
quired, 8^ in.,
say 9 in., wide,
two for each side,
the upper one be-
ing 11 ft. 8 J in. long, and the lower one 10 ft. 6| in. long.
They should be placed together as in Fig. 8, and the centre
line struck as indicated at a b. Then by setting out the
dimensions shown on the diagram and drawing a slanting

Fi^. 7. — Suggested Method of Shaping the
Stempost

Every Boy His Own Mechanic

line at each end right across the two boards the rake for
the ends of the planks will be obtained, and the planks
can then be cut on those Hnes. Both sides of the boat
are the same, and it will be noticed that although in Fig. 1
a curve is shown, this curve is obtained naturally as a
result of the design and system of building and does not
need to be imparted to the planks by sawing to a curved
line. Indeed, it is of the utmost importance that the

f-f/dl--"^

5^*

'fp-*:W

top and bottom edges of the planks
be planed parallel. Vertical dotted
lines will be noted in Fig. 8. These,
as indicated, are 7^ in. apart, and
they should be transferred to the
actual stuff by means of square and
pencil before the sides are bent. They
indicate the positions of the upright
timbers on the inside of the boat,
which timbers are not added until
after the planks are bent.

A start may be made with the
actual building immediately the two
stems and four planks are ready.
Taking one of the lower planks, place
it on the stem in the rebate provided
for it, as shown in plan by Fig. 6, the
stem projecting by about f in. at the
bottom. See that the end of the
plank is close up in the rebate, and
secure it with three 1-in. brass screws.
Attach the second lower plank to the
same stempiece on the other side.
312

Building a Rowing Boat

Take the remaining stem and similarly screw it to the other
end of one of the lower planks. Of the two planks there will
now be three ends secured and one end free. The next
job is to get the amidships mould in place, but before
doing this the bottom corners must be notched out, if
not already done, to clear the 1-in. by f-in. oak strips
(known by the boat-builders as " chines ") which will
run along the inside of the boat in the angle between
sides and bottom. All three moulds need to be notched
out in this way. Place the largest mould in position
between the bottom planks, and see that it comes exactly
central (on the line a b in Fig. 8). Temporarily fix it
with a couple of screws tln:ough each plank, and you will
then be able to bend in the free end of the plank and screw
it to the other stempiece.

We can now add the upper planks, first by screwing
them to the opposite sides of the same stem, and then
drawing the free ends together, tying tightly with a rope
and screwing as before. The rope can be tightened to
almost any extent by introducing a stick and giving it a
twist in the rope. This is a dodge that will come in handy
if you are working alone, but boat-building is a job for
two people as a rule, and can easily provide employment
for three.

The vertical dot-and-dash lines in Figs. 1 and 2 in-
dicate the positions of three moulds, one of which has
already been inserted. The two others will now be
dealt with. Each of them should be inserted amidships
and then forced towards the end until it occupies its
proper position, previously decided by exact measurement.
The moulds are 24 in. apart, centre to centre, and need to

313

Every Boy His Own Mechanic

be secured by rough strips nailed across their top edges
from the amidships mould, and, in addition, by a screw
driven in at each side through the bottom plank. There
is a certain amount of wedge action exerted, and were it
not for the screws the moulds would be forced upwards.

The chines already mentioned are strips of oak or
other hard wood which occupy the angle between the side
planking and the bottom. In section they are 1 in. by
f in., the 1-in. face being in contact with the sides, while
the other face needs to be planed to an exact bevel so
that the bottom boards will come flush and in perfect
contact. The chines should be attached to the side planks
with 1-in. No. 10 brass screws driven from inside and
spaced 8 in. apart. The notches cut in the moulds allow
of the chines being introduced at this stage of the con-
struction.

The upright oak timbers shown in side view in Fig. 3
are next to be inserted, their positions, 7^ in. apart,
having been already marked as previously instructed.
They will be about 18 in. long, 1 in. by f in., and should
be shaped at the top with spokeshave, chisel and glass-
paper after they are fixed, with 1-in. galvanised nails
3 in. apart, driven from the outside. These uprights are
not bevelled in any way, but require to be notched at the
foot where they pass over the chine.

The job is beginning now to look something like a
boat, and the attachment of the bottom planking will
make a big difference to the appearance. The planks need
to be of good stuff, but only those at the ends which are
liable to get a lot of rough usage need be of oak. The best
stuff to use is about 4| in. wide and not more than J in.

314

Building a Rowing Boat

thick, and, of course, the grain will run across the bottom
at right angles to the length of the boat. The first bottom
plank to go on is amidships, then work towards the ends,
and when complete trim off each stempiece, which until
now has projected a trifle, so that it comes quite flush with
the bottom. The planks are secured to the chines by
means of l|-in. No. 10 brass screws, three to the end of
each plank.

We have now got to the point at which the moulds
can be withdrawn, but, before doing so, it is wise to nail
a strip across from side
to side to the upright
timbers near each
mould so as to hold
the sides of the boat
together. Then you
can withdraw the
screws and remove the
moulds. The boat is now in recognisable shape.

There are two rubbing pieces on the boat — the keel or
bottom rubbing piece and the side rubbing pieces round
the gunwale, all of which are of oak and are shown in
section in Fig. 3 The keel piece is 3 in. wide by not less
than I in. thick, and is the exact length of the boat, it
being cut flush with the stempieces at each end. It is
fastened by means of |-in. brass screws, and these are
inserted in the style shown by Fig. 9, there being four
screws in each bottom plank, inserted close to the seams
as shown.

The side rubbing pieces attached to the upper edge of
the top plank are 1| in. wide, and at amidships f in. thick ;

315

Fig. 9. — Method of Screwing on the
Keel Piece

Every Boy His Own Mechanic

preferably they should taper to | in. thick at the ends,
where they should be rounded off. They are attached
with l|-in. brass screws which pass right through the
plank into the upright timbers. At the extreme ends
smaller screws fasten them to the stems.

There must be a floor other than the actual bottom
of the boat, but it need not extend the whole length. It
is supported on two strips of yellow pine or similar stuff
measuring f in. by 1 in. in cross section. These strips are
5 ft. 7 in. long, and are laid parallel to support 6 in. widths
< 50- -^-7-:f- - -30" ,.

III!
Mn

II-

liH^

jiit'^tl
:M1

Ezzi^z^^sa.

.^^^23:^

Fig. 10. — Plan and Elevation of
Floorboards of Boat

or 7J in. widths of |-in.
yellow pine, 18 in. long, as
clearly shown in Figs. 3
and 10. The latter shows
the floorboards and sup-
porting strips in plan and
elevation, and gives all
necessary dimensions.

There is a break in the middle as shown, which can take
a stretcher for the feet, or the edge of the flooring will
act as the stretcher. The strips are fastened to the
bottom planking with 1-in. brass nails inserted from
the outside.

To support the seats we need to provide oak risings or
risers, 1 in. by | in., running the whole length of the boat
from stem to stem. They should be about 7 in. below
the top edge, and their top edges need to be planed to
the correct bevel, as will be understood from Fig. 3.
They are attached by a l|-in. No. 8 brass screw in each
of the upright timbers. They support three seats, par-
ticulars of which are given in Figs. 11 and 12 ; these are

316

Building a Rowing Boat

of |-in. or 1-in. yellow pine, and about 7 in. wide, being
secured to the risers with three l|-in. brass screws at
each end ; of course, you will notch out the ends of the
seats to clear the upright timbers as may be necessary.

The actual construction is now complete, but the
caulking and painting remain to be done.

A practical boat-builder provides the following instruc-
tions on caulking the seams of a boat. Caulking cotton
or cotton wick can be obtained in 1-lb. balls. Two or
tliree strands about 16 ft. long are made fast at one end,
and the other end is twisted over the knee by hand,

-\ /-

\, 24'4- - -J

Figs. 11 and 12. — Centre Seat and End Seat

forming a thick thread, which, when fairly tight, is knotted
and rolled into a ball. When caulking, the ball is gradu-
ally unrove, and the thread is placed over and driven into
the seam with a caulking-iron and mallet. A thin chisel
ground to bluntness will answer the purpose of a special
caulking-iron. Drive in the thread as far as it will go,
care being taken not to burst the edge by too heavy a
blow. The next thread, which, if the joints between the
planks are a trifle V'd, may be a little thicker, is driven
on to this first thread, and so on until the seam is filled to
about I in. of the outside of the plank ; this space is left
for a stopping made of white-lead putty. Planking seams
are not usually filled with marine glue, as is done to the
deck seams of sea-going boats. If the craft is to be

317

Every Boy His Own Mechanic

varnished, the putty or stopping is coloured to suit the
planking. Wide seams are to be avoided, as the caulking
and stopping have a tendency to come out when the
planking swells.

As regards the painting for the outside, first coat
knots with shellac knotting (common shellac varnish), and
when this is dry give from two to four coats of reliable
paint. It is not usual to paint the rubbing piece at
the gunwale, which should be treated exactly the same as
the inside and as follows : Coat the knots as before and
then give two coats of boiled linseed oil, allowing a day or
two between them for drying, and finish with a good
flowing coat of good quality oil varnish.

Necessary fittings include two pairs of galvanised-
iron rowlocks with side plates, which can be bought ready
for attachment. It is desirable to have a ring bolt attached
to the stem as shown in Fig. 1, and you will, of course,
need a pair of oars and a l|-in. rope painter.

318

A MODEL AEROPLANE THAT FLIES

I FEAR that when you look at the illustration given on
page 321 you will be tempted to think that such a model
is not worth making. It lacks the realism of some of
those beautiful structures of canvas and timber which
are sold at high prices in the toy shops, but it does one
thing that very few of those structures can do — it can
fly. It has been designed especially for beginners by
Mr. F. J. Camm, and he guarantees that flights of well
over a quarter of a mile are easily obtainable with it.
It is built for flying and not for looking at. Fig. 1 is a
plan of the aeroplane showing the main spar running
down the centre strengthened by a bracing with outrigger.

Its technical description is a twin-screw monoplane,
propeller or canard type, hand-launched ; type formula,
" 1 — 1 — P2." At the front of the machine is an elevator
and at the rear two propellers, while well to the rear, but
adjustable as to position, is the main plane.

We wiU talk about the main spar first : it is a piece of
straight-grained birch J in. wide, ^ in. deep, and 48 1 in.
long, tapered at the ends to about ^ in. square. At the
rear end at right angles to the main spar is a propeller
bar, for which the most suitable wood is spruce ^ in. wide,
f in. deep, and 12| in. long. In the end of the main spar
is 4B, slot to receive the bar, which is held in position by

319

Every Boy His Own Mechanic

pinning and gluing. Fig. 2 shows how the propeller bar
is fastened to the main spar. From each end of the former
is a stay, jointed, as shown in Fig. 3, by notching and
pinning ; and the other end of each stay is connected to
the main spar at 6 in. from the end {see Fig. 4). A little
hole or mortice is cut in the spar to receive tenons cut on
the ends of the stays, the tenons abutting in the centre of
the mortice as indicated in Fig. 5. The joints may be
bound with strong silk or other thread to strengthen them.
A suitable binding material is three-cord carpet thread.

At each end of the propeller bar is bound on a little
bearing of sheet brass, which receives a wire axle con-
nected to the propeller. Each axle is driven by an elastic
motor. The little bearings are cut from scraps of No. 20-
gauge brass ('036 in. thick), and in each of them is drilled
a hole to allow the propeller shaft to turn quite freely.
This hole is indicated in Fig. 6 (which shows the bearing
bound to one end of the propeller bar), and should take a
shaft of No. 18 gauge, that is, '048 in. thick. It will be
noted that the bearings project from the ends of the bars
and are slightly bent so that they come at exactly right
angles to the skeins of rubber which drive the propellers ;
otherwise the propellers will rub on the bearings and
power will be lost.

The propellers are 12 in. long and are cut from pieces
of white wood 1| in. wide by f in. thick. The general
shapes of propellers are given in one of the photographic
plates, and it will be understood that one propeller must
be right-handed and the other left-handed, and that they
will revolve in different directions. There should be no
difficulty in shaping them with a good sharp penknife

320

BUILDING MODEL AEROPLANES

■

^^^

Carved

Propellers

for

Model

eroplane

Model of the Historical Wright Biplane

Built-up Propellers for Model Aeroplane

w —

•a

l~S

- »J

k-=

-^-•^ ^

321

Every Boy His Own Mechanic

whittling them away until a nice smooth outline and an
unbroken curve have been obtained. A tiny hole is
bored through them centrally to take a wire shaft which
should pass through them, and its end be bent flat so that
binding with thread will hold the propeller to the shaft ;
or, preferably, the shafts should be soldered to tin straps,
as in Fig. 7. The shaft from propeller to elastic is 4 in.
or 5 in. long, and ends in a hook to take the rubber
skeins. At the other end of the machine a double hook
is bound to the nose of the main spar to receive the
front ends of the skeins, as made clear in Fig. 1.

Fig. 7 shows a pair of bent-wood propellers that would
be suitable. They are pieces of jV in. birch, 12 in. long
and 1^ in. wide, and may easily be softened for bending
by holding them in the steam from a vigorously boiling
kettle. Each propeller has a pitch of about 37*5 in. ;
in other words, each blade tip makes an angle with the
spindle of 45°. Thin tin is wrapped round the centres of
the propellers so that the shafts can be soldered on.

The spar is considerably strengthened by a wire
bracing and outrigger, the latter passing through it, as
shown in the detail (Fig. 8), and consisting of a piece of
hard-drawn brass wire. A tiny hole is bored to receive
it, the wire inserted, bent on both sides of the spar as
indicated, and then tightly bound with thread. Fig. 9
shows it more clearly. From spar to the end of each arm
measures 2 in., and at each end is a small eye. The fine
bracing wire is attached to the spar at the points indicated
in Fig. 1 by means of small hooks of No. 20-gauge wire
bound on, and the bracing wire will require some
amount of adjustment, as there must be exactly the

322

A Model Aeroplane that Flies

same tension on each side of the spar, otherwise warping
is certain.

The elevator must be so made and fitted that its in-
clination can be altered to control more or less the height
attained by the machine when in flight. Its framework is
a rectangle, 15 in. long and about 3 in. wide, with three

Fig. 5. — Joint of Stay
with Main Spar

Fig. 6. — Propeller Bearing
Bound to Bar

Fig. 7. — Pair of Bent-wood Propellers

cross pieces to strengthen it, made of No. 18-gauge ('048
in. thick) wire. In making this rectangle, the joints need
to be bound with fine tying wire and soldered. The
elevator's central rib is longer than the others and projects
forward and downwards, as shown in the side-view detail
A, Fig. 1. The wire passes through a fine hole made in
the main spar, the hole being bored in such a way that
the wire binds in it with sufficient friction to retain the
elevator at any angle to which it may be set, at the sam^

323

Every Boy His Own Mechanic

time allowing of its swivelling should it strike any object
in the course of its flight. I will deal with the covering of
the elevator plane later.

The main plane has a frame roughly rectangular in
form, about 30 in. long at the back edge, and 26| in. at
the front edge. The least width is 5 in., and the width
along the main spar in the centre is 5f in. The framework
is built up not with wire, but with birch wood J in. by

'■nAiNaR*p

Fig. 8 Fig. 9

Figs. 8 and 9. — Outrigger Passing through and Bound to Spar

■^ in. in cross section. Fig. 1 shows that the spar at the
back, known as the trailing spar, is curved. The wood
can easily be bent in the steam from a kettle, or after
soaking for a few moments in hot water, or after wrapping
in cloths that have been lightly wrung out in very hot
water. There are five ribs as shown in Fig. 1, and they
are attached to the frame by pinning and gluing, the pins
being clinched on the underside. You will note that the
central rib is longer than the others, and slightly projects
over both the spars to afford means of securing the main
plane to the main spar. These means are very simple,
consisting simply of two little strips of thin tin which
slide tightly along the spar and clip the projecting ends
of rib in place {see Figs. 10 and 11). The strips are made by
bending up small pieces of thin tin, lapping the ends, and
soldering. To shift the main plane fore or aft is thus

324

A Model Aeroplane that Flies

an easy matter. The main planes have diagonal wing
bracing secured as in Fig. 12, and this bracing is put under
such tension that there is what is known as a dihedral
angle of 1| in. ; in other words, the wing tips of the
main plane are 1| in. above the spar {see Fig. 13).

The motor that propels the aeroplane consists of
sixteen strands of J-in. strip rubber, eight to each pro-
peller, and they should be lubricated with soft soap.

_ iJedion

Fig. n

Figs. 10 and U. —Adjustable Attachment of Main Plane to Spar ;
A, Pattern for Clip

All the bindings on the machine should be coated with
weak glue or with varnish to strengthen the work.

Mr. W. G. Smith, a very successful builder of
aeroplane models, contributed to Work the following
explanation of his simple method of forming and covering
the planes. I reproduce it here because it is essentially
practical, and one easily followed by the boy builder.
" For the planes of model aeroplanes, steel wire offers
exceptional advantages, as it is practically unbreakable,
and can be bent to any desired shape. Another advantage
is that it offers a minimum resistance when travelling
through the air. First obtain a piece of wood about
I in. thick and slightly larger than the plane to be made,

325

Every Boy His Own Mechanic

and draw on it a plan of the plane, as in Fig. 14. For
example, it will be assumed that a plane 30 in. span and
5 in. wide, having four ribs, is to be made. No. 17 s.w.g.
steel wire will be used, and will need to be straightened.
Then lay the wire over the plane, beginning at a (Fig. 14),
and passing round to b. As the wire is bent to the shape
of the plane, it must be fastened down to the board by
means of small staples. Then cut four pieces of wire
for the ribs c, d, e, and r, allowing | in. each end for

Crot''} Tn'eadb_

Fig. 13 Fig. 12

Figs. 12 and 13. — Wing Bracing to Give Dihedral Angle

turning at right angles as in Fig. 14. The framework is
now ready for soldering together. The wire and soldering
bit must be perfectly clean. Apply a little ' killed spirits '
to the parts to be soldered, and then place a piece of solder
in position and touch with the hot bit. Care must be
taken to see that the wires lie close together. When the
plane is soldered together, remove all the staples and
clean up all the joints with a file. The joints must be
bound round tightly with clean fine iron wire, the plane
fastened to the board again, and all the wired joints
re-soldered. Then the plane is once more removed from
the board, straightened, the dihedral angle given, and
the ribs bent to the desired camber.

" For covering the planes, it is far better to purchase
a waterproof silk especially manufactured for the purpose.
It weighs about 1| oz. per square yard. When cutting,
about I in. must be allowed for turning over for fastening.

326

A Model Aeroplane that Flies

At the curved ends of the plane, slits about | in. apart
must be cut in the edge, as shown in Fig. 15. Apply a
thin coating of seccotine to the silk to be turned back,
and allow sufficient time for it to get ' tacky.' Then
stick over the plane, beginning at a (Fig. 15) and finishing
at B. Allow time for the seccotine to set, and fasten the
opposite end in the same manner. Care must be taken
to stretch the silk tightly, so that it is free from wrinkles.
Then fasten first one side of the plane and lastly the
other. Another method of covering steel-wire planes

Fig. 14, — Making Frame for Main Plane

Fig. 15. — Covering Frame of Main Plane

is to sew the silk on the framework. The silk must be
cut about I in. larger than the framework, and the edges
hemmed with a sewing machine. The silk cover when
hemmed should be slightly smaller than the framework.
First sew the silk roughly into position, and then carefully
sew it, beginning at one end, then the other end, and
lastly the sides. The stitches, I in. apart, should first be
passed through the silk, and then round the wire.

The machine should be tried and any necessary
adjustments made. Any tendency to dive should be
corrected by moving the main plane forward.

327

NAILS AND SCREWS

Some amount of care and common sense is necessary
in using nails, which must be started in the way in
which they are to go. For all rough carpentry the
French or wire nail, which is made in a variety of sizes,
will be found good enough, but I often prefer the oval
steel brad, which is made in a range of sizes, and has to be
driven more carefully than the French nail as it is more
liable to bend. Panel pins, which are fine wire nails of

special manufacture,
are useful for good
work and in the repair
of furniture where the
use of thicker nails
would probably mean
splitting the wood.
Before driving in a nail take a moment to consider the
direction of the force which the nail will have to resist.
Say, for example, that Fig. 1 represents part of the
bottom of the box ; the weight inside the box will be
pushing down on the boards, and therefore if the nails are
driven at exact right angles they will be loosened sooner
or later, whereas if they are driven slightly on the slant,
and at an opposite slant as illustrated, a dovetail effect
is produced. This is a point worth remembering.

328

—Nails Inclined to give
Dovetail EflFect

Nails and Screws

A frequent trouble in nailing is the splitting of the
work. Thoughtlessness is often a big factor, and you
should never insert nails in such a way that their com-
bined effect is to split the board along one line of the grain.
Wherever possible, zigzag the nails, so that they cannot
help each other to split the wood. A little nail-set, which
is a cheap tool, is worth having, as with it the nails can be
driven right into the wood without damaging the work —
and hammer marks on finished
woodwork do not look well.
When withdrawing nails do
not forget to introduce a bit
of scrap wood or something
of the sort under the pincers
so that in levering out the
nail the surface of the work
itself is not marked.

The screw is, of course, a
stronger method of fixing than the nail. It is actually
a form of cramp, and one frequently sees it inserted in a
very careless manner. In screwing boards together the
screw should be a loose fit in the board nearest the head,
and a tight fit in the other one ; thus you gain the effect
of squeezing or cramping the outer board between the
head of the screw and the board underneath. Fig. 2
shows what I mean. A touch of fat or oil on the screw
helps the insertion and makes withdrawal easier at a
later date.

Fig. 2. — Diagram showing
Clamping Action of
Screw

329

SOME USEFUL JOBS ABOUT THE HOUSE

Erecting a Shelf. — One of the most useful jobs about
the house fallmg to the lot of the boy mechanic is the
putting up of a shelf. Now, in the case of a recess in your
den or bedroom in which you may wish to erect a book-
shelf, the simplest method is to fix wooden bearers, one
on each end wall, and support the shelf on them. There
is a right way and a sadly wrong way of attaching a
bearer to a wall. Most people have tried the wrong one
and have found that by hammering big nails through the
wooden bearer into the wall they manage without any diffi-
culty to make a mess of the wall, or to arrive at a hard spot
in a brick which the nail cannot penetrate. There is no
natural hold for a nail in either brick or mortar, and often-
times a bearer which is simply nailed to a wall will come
down when the weight of a heavy bookshelf rests upon
it. The right way is to " plug " the wall, and this is done
by drilling two or more holes | in. to f in. in diameter
by means of an old chisel ; special tools for the purpose
can be bought {see Figs. 1 to 5), but I have always
made do with a blunt wood chisel that was of no further
use for its original purpose. Cut the hole about 3 in.
deep, shape a plug of hard wood that will make a tight fit
in it, and drive it in with a hammer. Two such plugs as
this, 1 in. to 1| in. from the respective ends of the bearer,

330

Some Useful Jobs about the House

will support a great weight. Select the screws you are
going to use and bore holes through the bearer to take
them easily. With a bradawl make a small hole in each

Fig. 2.-

Cutting
Edge of
Hollow
Chisel

Fig. I.— Hollow
Chisel f o r
Plugging
Walls

Fig. 3 Fig. 4

Figs. 3 and 4. — Cruciform
Chisel ior Plugging
Walls

Fig. 5.— Flat
Chisel for

Fig. 6. — Ensuring Tidiness : Paper Pinned up Plugging

to catch Plaster, etc., when Plugging a Wall Walls

of the plugs, and on driving the screws home you will get
a very tight attachment. Be as neat and tidy as you
can {see Fig. 6).

An excellent way of proceeding is to prepare the bearers

33^

Every Boy His Own Mechanic

and bore the two or three screw holes that will be required.
Place the bearer in position on the wall, and mark through
the end screw hole with a bradawl. Remove, plug the
wall as before explained, and attach the bearer loosely
with a screw. Then by means of a spirit level used as in
Fig. 7 you can get the bearer truly horizontal, and with a
bradawl can mark the positions of the other plug or plugs.

The erection of one bearer should be finished before
starting on the other, particularly so if you are in doubt
as to whether you can get your shelf horizontal. Support
the shelf on the bearer already fixed, place the bearer
under the other end, and raise the shelf until the spirit-
level indicates that the shelf is horizontal lengthwise ;
then mark through the screw holes with a bradawl and
plug the wall for the second bearer.

Sometimes a recess will not have its end walls at a right
angle with the back wall, and it will be necessary to adopt
some means of transferring the angle to the shelf so that
it can be sawn to shape. Fig. 8 shows how this can be
done with an ordinary folding rule that is fairly stiff in
the joint. Take the angle of the wall with the rule and
transfer the latter to the board so that the part a comes
flush with the back edge, and the part b lies over the front
corner of the board. Then with a chisel or sharp point
mark the angle line and afterwards cut to shape with
the saw. The erection of the bearers in a case of this sort
is exactly the same as before, but it makes a neater job
if their front ends are sawn or chiselled off to be in the
same vertical plane as the front edge of the shelf.

When erecting a shelf on the face of a wall where there
is no recess, bearers are out of the question, and instead

332

Some Useful Jobs about the House

wood or iron brackets must be used. The professional
carpenter favours the first, but the boy mechanic saves
himself a great deal of labour by using iron brackets,
which can be bought quite cheaply. Do not forget that
to make a proper job you will need to plug the walls as
already described. Possibly you will find that the screw
holes in the brackets are just -opposite joins between the
bricks, and if so, an amount of hard work in drilling will

Fig. 7.— Getting Shelf Bearer
Horizontal

be saved, it being, of course, much easier to plug a joint
than a solid brick. Do not forget, either, that a shelf
that is not quite horizontal is an offence to a trained eye ;
it can easily be made horizontal by means of a spirit level,
and I have even known a glass of water used as a testing
device. Failing these, get somebody to hold the second
bracket, the first having been fixed, and get back a good
distance from the wall so that your eye may decide whether
the shelf is level.

333

Every Boy His Own Mechanic

In many houses, walls in the upstairs rooms are not
what they seem ; they look so solid, but are actually
only wooden partitions covered with lath and plaster. It
is no use plugging these. Instead, find out by tapping
with your knuckles where the upright timbers of the par-
tition come. Your ear will soon tell you the difference
between the hollow partition and the solid timber. Then
you can attach your brackets or bearers with long screws
right through the lath and plaster into the timbers.

Sometimes, to minimise the number of wall plugs,
shelves and wooden brackets are hung on what are known
as "glass plates" or hangers, these being metal plates in
which there are generally two screw holes for attachment
to the article, the top hole being for the screw which holds
the plate to the wall or wall plug.

It very often happens that the screw holes in iron
brackets, glass plates, etc., are slightly too small for the
screws which you happen to have, but there will be no
difficulty in slightly enlarging them with the tang or rat-
tail of a file.

By the way, in choosing iron brackets you should give
preference to those that are of triangular form rather than
to those which are simply pieces of iron bent to L-shape.

Cleaning Locks and Renewing Lock Springs. — I have
always taken a great deal of interest in locks, and I expect
that you have enjoyed the task of taking one carefully
to pieces, noticing the position and the function of each
part before you removed it, and doing your best to under-
stand how the lock works. I took to pieces a very com-
plicated lever lock some time ago, and was almost afraid
of it when I unscrewed the plate and saw the amount of

334

Some Useful Jobs about the House

mechanism in it ; but I proceeded carefully, scratching a
tiny number on each plate as I removed it so that I could
be certain of replacing it in exactly the right order. 1
made a mental note of the position of every part of the
contrivance, and did not remove a single piece until I
was quite certain that I should know where it belonged
when the time came to put it back again. The lock
had probably not been opened for twenty-five years ;
it was dry and contained a quantity of rusty powder,
together with a quantity of old solid oil. The powder and
the dry oil had caused the lock to work very stiffly, and
I took it apart to see whether I could remedy matters.
Having taken all the precautions named, I put the very
dirty parts — those covered with the congealed oil — into
some boiling water containing a handful of washing soda,
and left them there a couple of hours. Then I passed
them through some clean boiling water, dried them, and
rubbed them up with a rag and some knife polish. I
cleaned out the case of the lock and carefully reassembled
all the parts in the order in which I had originally found
them. As I put the brass levers in place, I tested them
with the key to make certain I was not in error. I lubri-
cated all the surfaces that rubbed on one another, tried the
action several times to see if everything was right, and put
it back in its place on the door. This was a very heavy
rim lock, the sort that has an iron or steel box or case
visible on the inside of the door, and which could be very
easily removed by taking out a few screws in addition to
withdrawing the handle stem after removing a tiny set
screw in the handle.

Locks that are hidden in the woodwork of the door are

335

Every Boy His Own Mechanic

known as mortice locks, and they are more trouble to
remove ; there are generally one or more, frequently two,
plates on the edge of the door which have to be unscrewed,
but the lock will not move until the handle has been
taken out.

I cannot go fully into the mechanism of locks in this
chapter, as the subject is a very large one, and I will
content myself with just one more hint. A very common
trouble in door locks is the failure of the latch to work
properly. The handle is turned, the latch recedes into
the lock, and when the handle is released it fails to make
its appearance ; thus the door does not latch when it is
slammed, and soon gives annoyance. There is one cause
for this — the lock spring is broken. This spring may be
of any one of a score of different shapes and sizes. It is
made of thin steel, and as this metal is very susceptible to
the effects of moisture, it does not take many years for the
spring to rust through, or the spring may break simply as
the result of wear. I took to pieces a lock the other day
suffering from a broken spring, and when I unscrewed
the plate the two parts of the spring fell out. You must
know that there is a great variety in locks and hundreds
of different patterns, and I confess that at first I did not
recognise how the spring acted ; I found out, though, in
a very simple way, and that was by taking off another
lock of the self-same pattern, very carefully removing the
plate, and studying the internal anatomy.

You can buy lock springs at about one penny each from
any ironmonger, and there is no need why, if you are
prepared to exercise a little thought and patience, you
should not keep in order all the door locks jn your house.

336

Some Useful Jobs about the House

Putting: a Washer in a Water Tap. — In every house-
hold at some time or other a water tap gets leaky, and
however hard the handle may be screwed down there will
be a constant stream of water from it. The trouble is
that the constant pressure of the water or the screwing-
down of the tap has worn away the leather or compo-
sition washer, and this requires to be renewed — a very
simple job indeed, but one which is very puzzling to
some people. First of all get one or two new washers ;
for ordinary cold-water taps, these washers may be of
leather or rubber, but for hot-water taps the best kind is
made of red vulcanised fibre. The ironmonger stocks all
sizes, and will guide you in the matter.

It is best, wherever possible, to turn off the water at
the stopcock, but this sometimes is inconvenient, and
frequently also the tap is fed by a pipe from a big cistern,
and the cutting-off of the water could not be effective till
the cistern were empty. Sometimes a broom handle or a
big cork can be used for stopping the outlet from the
cistern, but occasionally it happens that the renewal of
the washer must take place with the water running until
the new washer is in place. Greater care is then necessary,
especially if the tap is directly connected to the main
water supply, in which case the pressure is so great that
on removing the top part of the tap there will be a fountain
of water that may reach the ceiling. If the water must
run all the while, get somebody to hold a pail upside down
immediately over the tap, and be prepared yourself for
an occasional squirt of water over you ; do not unscrew the
tap at c (Fig. 9) or you will be flooded.

With a spanner, such as an adjustable cycle spanner,
w 337

Every Boy His Own Mechanic

unscrew the top part (above b), which will bring with it
the threaded stem or plunger, in the bottom of which is a
jumper {see Fig. 10) covered with the old washer. The
method of getting off the washer will be self-evident, I
expect, but it varies with the kind of tap. Sometimes a
little nut or screw has to be removed, but in any case
you will find no difficulty here. Put on the new washer,
which will, of course, be the same size as the brass plate,
and before replacing the top part of the tap loosen the

Fig. 9. — Water Tap (Screw-down
Bib Cock)

Lc(it}ltr LOo^hcr

Fig. 10. — Jumper and
Washer of Tap

bush or gland a which screws into the body of the tap
just against the handle. In the meantime, if the water is
running, your assistant must have kept the pail in position
all the time so as to throw the water down into the sink.

You now push the stem with its new washer into
place. This may require a little force, and occasionally a
tap or two with the hammer will help matters considerably.
Then tighten up with the spanner and adjust the brass
bush A, so that you get a nice easy action.

If the new washer does not wholly cure the trouble it

338

Some Useful Jobs about the House

will be found that the metal surface on which the new
washer presses down has become roughened or pitted
by the water action, and those surfaces will need to be
ground, which is a job not usually undertaken at home,
but a special tool for the purpose is obtainable. I
suggest you can often improve a bad seating by dipping
the end of a piece of wood in oil and coarse emery and
then revolving it between your hands inside the tap.

Loosening a Stuck Window Sash. — You are fairly cer-
tain to be called on to loosen a window that has become
stuck, the cause of the trouble possibly being the care-
lessness of a painter in allowing one sash to become
cemented by the paint to the other sash or to the window
framing. I strongly recommend you not to use screw-
drivers or chisels in your attempt to loosen the frames. It
is almost impossible to use edge tools for this purpose
without marking the paint, and frequently their use will
give no good result. I find there is one method which
seldom fails. I place two or three old thick magazines
on the woodwork of the stuck frame and give a very
sharp, quick blow with a hammer. The paper spreads
the blow and prevents any damage to the paint, and, as
a rule, the blow breaks the paint contact instantly ; if
not, the blow can be repeated. Sometimes it may be
necessary to lay a block of wood on the bottom rail of
the sash and give a smart blow on that, of course taking
care and using all your skill to prevent damaging the glass
or frame. It is a very simple remedy, which is far to be
preferred to the use of sharp tools.

339

A WORD ON WOOD

Packing cases provide a great deal of useful material for
rough carpentry. They should be carefully taken to
pieces, preferably by leverage with an old strong screw-
driver, and the nails removed one by one, straightened
and put aside for use later. Tea chests yield three-ply

wood, which is excellent stuff,
consisting of three thin pieces
of wood glued and pressed
together, the grain of the
middle one being at right angles
to that of the outside pieces.
Nowadays, wood can be bought
already planed and cut to the
exact length required, and this
is a great advantage. It is often
of interest to know in which
direction a board is liable to
shrink or warp, and this can
Fig. 1.— How Boards and Pcbts generally be determined by

Shrink and Warp ,, t ^- i? i.i. i

the direction oi the annual
rings, which show so distinctly in the end grain. Take
for example, a tree trunk cut into four slices a b c b {se
Fig. 1, above), and into two square posts e f. As the
wood dries, the rings get shorter, with the result that the

34^

A Word on Wood

surface of the wood which is farther from the heart of the
tree is inclined to go hollow as shown, whereas a board or
slice cut right through the centre gets round and not
hollow on both its faces. Square pieces tend to become
of a diamond shape, and wherever in special cases it is
desirable that the squareness should be maintained they
need to be cut so that the end grain shows as in G h.

In buying small quantities of wood the material is sold
by the square foot, or by the foot run, the price in the

Fig, 2. — How a Log may^SpIit in Drying

first case being based upon 1 in. of thickness ; thus per
foot run 6 in. wide and 2 in. thick would be the equivalent
of 1 sq. ft. at 1 in. thick. /

Shrinkage in a felled tree trunk often results in splitting,
as shown in Fig. 2.

The woods in general use number some hundreds (as
a matter of fact, I give particulars of over three hundred
of them in " The Complete Woodworker," a volume in

341

Every Boy His Own Mechanic

Cassell's Handcraft Library, which the boy mechanic who
has mastered the instruction given in the present book
would do well to get). I can afford space for mention of
just a few of the best known and most useful.

Ash is close-grained, hard and tough. Beech, another
excellent wood, is also of close grain : the former is of a
light brown colour, and the latter yellowish-red. Elm is
of a yellowish brown, hard and durable. Larch, yellowish
to reddish brown, straight grained and tough. Mahogany
varies considerably, the best being heavy, hard, close
grained, and excellent in most ways. Maple, reddish
white or reddish brown, is tough, hard and fine of grain.
Oak, generally light brown and very characteristic in its
markings, is very strong, tough, and hard. Pine, light,
durable and easily worked, is among the cheapest class of
wood for general use. Spruce, another easily worked
wood, is of straight and even grain. Teak, one of the
most durable woods known, is of a brownish red colour.
Walnut is close grained, durable, of a brownish colour and
beautiful in appearance.

34^

A PRACTICAL HOME-MADE TELEPHONE

By B. Clements-Henry

For some years previous to 1914 the constructive instinct
and ability inherent in many of us was ahnost snuffed
out because i..w>:,t of the mechanical and electrical things
we wished to possess were so cheap that they could be
bought ready made. Often the prices quoted were actually
below the cost to us of the raw materials, and so we came
to think that constructive hobbies were a bit futile.
Lots of those cheap things were amazingly good, but some
were exasperatingly bad, and the bulk indifferent. Still,
we bought the stuff, learned nothing from it, and clean
missed all that solid satisfaction that lives for ever in
building and contriving and creating.

Take the ready-made cheap telephone, for instance.
How long did it take to get fed up with ringing and asking
" are you there ? " Was it really worth the outlay of
15s. to 45s. ? Frankly, no. Why ? Because our pur-
chase locked us out from all the subtle mysteries of an
ever-wonderful instrument (simple though it be), and we
had been robbed of all the j oy of its making. If it failed to
act we discovered that we could not put it right. If it
acted perfectly, we took the whole thing for granted and
soon became bored. But to build up that same installation
oneself in the face of difficulties from the homeliest of

343

Every Boy His Own Mechanic

raw materials, and at last to have it (in literal fact)
voicing our triumph in our eager-listening ears — ah,
that is a very different matter !

The writer has been asked to simplify everything in
the making of a home telephone down to an irreducible
minimum ; and he will do his best ; but he must assume
that the boy mechanic knows by this time something of
the use of tools. Readers who are better equipped than
most with tools and the skill to use them can improve on
primitive methods here and there. The whole design is
original to this book, and was thought out especially
for it with a view of reducing the difficulties of construc-
tion to the utmost, yet to retain every essential detail
that goes to make up a reliable and efficient installation
capable of calling up, speaking and hearing as well as
any first-class telephonic apparatus can. Some of the
parts have been practically re-invented to attain this
end, and the least experienced boy mechanic who cares to
follow these instructions to the letter can be definitely and
confidently assured of the complete success of his under-
taking.

Through want of space the theory of the telephone
cannot be discussed here, but those who wish to master
its beautiful simplicities can do so by an hour's study of
Cassell's "Work" handbook on the subject. In the
present chapter points of difficulty or of importance will
be emphasised (without explanation) by the use of italics.
Where these appear the reader is asked to sharpen his
wits and exercise special care, adhering closely to the
instructions — blindly so, if need be ; and rest assured
that they will not " let him down."

344

A Practical Home-made Telephone

This installation is a " real " one in every respect.
It consists of two series-type wall-sets having electric
call-bells, hand-combination telephones slung on auto-
matic hook-switches, calling press-buttons and batteries
complete. It will speak clearly and distinctly over 150
yards of No. 20 gauge line wire, and farther if thicker line
is used.

The Kand-Combination Telephone. — The hand-com-
bination (of transmitter and receiver in one) is familiar to
most people, and even in its practical home-made form,
shown in Figs, 1, 2 and 3, it will be easily recognisable.
This being far the most complicated part should be tackled
first, and it would be best to build the necessary pair (one
for each station) concurrently.

Fig. 1 shows the front of the instrument — the receiver
above and the transmitter below. Fig. 2 is a side half-
section showing all the working parts ; and Figs. 3 is the
back view, in which the wiring connection is seen pro-
ceeding from the left-hand terminal screw (at the bottom)
to the left bobbin of the receiver, through its winding and
that of the right bobbin and back to the metal cover of
the transmitter. The other terminal screw is wired direct
to the carbon block in the centre of the transmitter.
The several wire ends appear also in the side section
(Fig. 2).

The woodwork must first be made ; it consists of three
parts ; the body A and the two discs b and c, which are
glued to the face of the body. Mahogany, teak and
walnut are the most suitable woods ; beech and oak will
serve admirably, but are harder to work; deal is scarcely
good enough.

345

Every Boy His Own Mechanic

The body a is 9 in. long over all, by about 2| in. wide
across the circular ends; the exact size of these will
depend on the diameter of the two tinplate box-lids used
as covers for the transmitter and receiver [see Figs. 1 and
2). Tooth-powder or boot-polish tins vary in size, but
the lids should be selected of not less than 2| in. and not
more than 2| in. in diameter, the former size being here
illustrated. The wood should be exactly | in. thick when
planed up and glasspapered smooth and flat.

First cut out the body a with a keyhole saw, and
shape it by careful paring with the chisel and by glass-
papering. The midway handle part may be | in, to 1 in.
wide, and should be rounded off neatly to form a con-
venient grip, as shown, the disc ends being finished quite
flat. The discs themselves, b and c, are of the same | in.
wood; they must be sawn out, pared and glasspapered
to make a close and accurate fit for the tinplate box-lids.
The transmitter disc (below) has a 1-in. diameter centre-
bit hole bored through its centre, and the receiver disc
(above) has two y|-in. or |-in. holes carried through it,
side by side, their centres being spaced a shade more than
f in. apart, say |i in., which will cause the holes to cut
into one another.

If preferred, all these holes can be bored in the board
before cutting out the discs therefrom, but the better way
will be to attach the finished blank discs to the body and
bore them afterwards. A good, durable joint can be
made with glue alone, applying it rather thin and very
hot, the discs being quickly and firmly pressed and rubbed
into close contact with the body, and then put aside under
heavy pressure to set for twelve hours ; a copying-press

346

Fig. 1

Fig. 2

Fig. 3

Figs. 1, 2 and 3. — Front Elevation, Vertical Section and Back Elevation
of Home-made Hand-combination Telephone. (Scale, 6 in. = 1 ft.)

347

Every Boy His Own Mechanic

or a linen-press can be used, or failing these the body may-
be laid on a flat surface, discs downward, and weights
piled on its ends. If preferred, three equally spaced
|-in. brass wood-screws can be used additionally to the
glue ; but care must be taken to place these where
they will not interfere with fittings to be subsequently
attached, as shown in the illustrations.

After the glue has thoroughly set, the holes must be
bored ; if any difficulty is anticipated in making them
neatly and accurately, any working carpenter will bore
them for a trifle. The 1-in. hole at the transmitter end
goes through the disc c only, but the two ^-in. holes at the
receiver end pass right through b and the body a also.
This being done, drill holes for and fit the large screw-eye
seen at the top and the small one at the bottom ; then
remove them again, temporarily. Fit also the two tin-
box lids, finally, to the discs, remove them, glasspaper
the woodwork all over, and fill the grain thoroughly with
a good body of french polish applied with a brush.

The receiver-magnet m is one of the ordinary horseshoe
type obtainable at toyshops ; the 2 in. size is chosen for
illustration, but it may be larger if the woodwork is
adapted to suit. It is important that its magnetism be
strong, and the two magnets required should be care-
fully selected from a batch ; they should easily support
at least four times their own weight suspended from the
keeper. The poles of each magnet must be fitted with a
stout sheet-brass clip shown at l (Figs. 2 and 3), and on an
enlarged scale in Fig. 4. The brass may be ^ in. thick
or a trifle less, by about | in. wide and If in. long. Mark
the points at which the ends are to be bent by laying the

348

A Practical Home-made Telephone

magnet-poles upon the brass, and lightly scribing a line
outside each limb. Then bend at right angles in a vice
or pair of strong pincers and finish the hooked ends by
beating down over a strip of flat metal of similar sub-
stance to the magnet. (Do not beat the brass on the
magnet itself, because the steel is hard and brittle and
may snap). Make the cHp a very close push-on fit for
the pole ends, and then file to about | in. width, as shown,
so that, when pushed on as far as
the slant of the limbs permits, the
upper edge of the brass ex; ends
about ^ in. beyond the pole-faces.
Now drill two ^-in. holes through
the clips a shade more than | in.
apart.

Obtain from any ironmonger a
piece of ^-in. " nail-rod," which
is ordinary wrought iron ; better
qualities of iron such as Bessemer
or mild steel will not do so well.
From this, cut off f in. lengths for the pole-extensions
that are to carry the bobbins (all of which are shown in
Figs. 2, 3 and 4). File up bright all over, and make all
exactly of one length with the ends perfectly flat. Fit
these pole pieces into the holes in the brass clips, very
tightly and truly upright, with their inner ends very
slightly projecting through the brass. If they were riveted
into the brass the iron would be hardened and rendered
less permeable by the magnet-flux of the magnet, so the
pole-extensions must be soldered into the holes. If all
the parts are quite clean and bright and plenty of zinc

349

Fig. 4. — Full-size Details

of Clip, Cores, Bobbins,

and Magnet-poles

Every Boy His Own Mechanic

chloride soldering fluid (" killed " spirit ; see p. 126) is
applied, together with a few scraps of solder placed round
the iron cores, the joints will solder themselves if the brass-
clip is held in pincers over a gas flame. Get a good run of
solder round the base of each pole-extension, then cool
off, quench in water, and wash thoroughly to remove the
acrid flux. File the pole-ends bright again, carefully
removing every trace of solder from the two inner end-
faces, and use every endeavour to make these set flush
and hard upon the faces of the steel magnet when the
clip is pushed on as hard as it will go. That is why the iron
ends must project a trifle through the brass — to make
certain that they (and not the brass) are pressed hard and
flat against the magnet.

It should now be found that most of the magnet's
attractive force is transferred to the tips of the two iron
extensions \ which is as it should be.

The bobbins are made up of glued paper tubes with
wooden or cardboard ends glued on. Cut off a piece of
the ^-in. iron rod about 2 in. long and file it bright and
smooth. This makes a mandrel, or former, on which to
roll a paper cylinder long enough to cut into two bobbin
tubes. Cut a strip of medium notepaper about 1| in.
wide by If in. long ; roll this lengthwise round the mandrel,
which it will be found to lap about three times. Unroll,
mark the line of the first overlap and dress the remainder
of the strip with thin hot glue ; roll up tightly and com-
press by rolling on a flat surface under a piece of smooth
board with considerable pressure. When consolidated
the tube can be slipped off the mandrel and dried. Cut
out two discs for each bobbin | in. in diameter, the central

3SO

A Practical Home-made Telephone

holes being a snug fit for the tube ends. Put the tube on
the mandrel, cut it in two, midway, with a sharp knife,
glue the discs on the tubes square and true to measure
I in, long over all exactly. Put aside for at least twelve
hours to harden, slip on to the mandrel again, trim off
the tube ends flush with the discs, glasspaper smooth all
over, and place in a cool oven for half an hour.

Meanwhile, melt some paraffin wax (paraffin candle
ends will do) in a gallipot stood in the oven. {Do not
overheat the wax). When this has melted and the bobbins
are quite dry and warm, soak them for a few minutes in
the wax, then drain, cool them off and polish with a dry
cloth.

When the bobbins are in position on the pole-exten-
sions and the brass clip l is pressed on to the magnet-
limbs, and the magnet is laid fiat upon the back of the
wooden body a, the bobbins should pass easily through
the ^-in. twin holes bored to receive them, and the end-
faces of the pole-extensions should be exactly level with
the face of the disc b, as clearly shown in Fig. 2. The
magnet m is secured to the body a by one mushroom-
head brass wood-screw passing through the brass plate n.
The triangular-shaped brass plate p is screwed to the
body as shown simply to prevent the pole-clip l from
slipping off the slanting poles of the magnet, as otherwise
it might be prone to do if the combination is roughly
handled in use.

Obtain from any photographic stores a sheet oi ferro-
type plate (which is thin Swedish iron sheet coated on
both sides with an elastic black enamel). Take a pair of
compasses and draw a 2-in. diameter circle on a sheet of

351

Every Boy His Own Mechanic

paper. Cut this out and gum it lightly to the ferrotype
sheet. Cut the ferrotype to match the pattern, then
soak off the paper and dry the enamelled disc. (Scissors
cut ferrotype very easily.) Compasses must not be used
to mark the disc direct because their centre-point would
dent or perforate the thin iron, whereas the disc must be
kept perfectly plain and flat. If, now, this iron disc
were laid on the surface of b it would, of course, touch
and cling to the magnetised pole-ends ; it must, therefore
be raised off the surface of b sufficiently to give it joom
to vibrate freely (like a drum-head) notwithstanding the
strong pull of the magnet-poles. But the air-space
separating the disc from the poles must be the least
possible that will just keep them from mutual contact.
This necessary spacing is effected by a ring or washer of
thin card gummed to the face of b ; the washer may be
of the same diameter as b (say 2| in.), and If in. inner
diameter (which will make it ^ in. wide). The pull of
the magnet will bulge inward the elastic iron-disc (or
diaphragm, as it must now be called) somewhat, but it
must not touch the poles. When testing, press the
middle of the disc gently with the finger-tip ; it should
touch the poles and be felt to cling to them on very light
pressure, but be released promptly when the finger is
removed. If one thickness of card does not suffice, gum
a thin paper washer over the cardboard one ; or if the
card seems too stout reduce its thickness by glasspaper-
ing. The diaphragm is fixed by laying another (and
thicker) cardboard (or rubber) ring upon it and then
pressing on the tinplate cover tightly. The whole ar-
rangement is clearly seen in Fig. 2, which shows the

352

A Practical Home-made Telephone

diaphragm d nipped between the washers w and w^, but
to make the drawing clear both the diaphragm d and the
thin inner washer w^ are shown much thicker than
they are in practice.

The aperture d in the centre of the cover is | in. in
diameter, it can be cut out very neatly with a centrebit
of that size, without damaging the tool. Three small
equi- spaced holes should be drilled in the rim of the cover
to take three small upholstery brass pins for securing the
cover to the woodwork when all is finished and the covers
finally pressed home.

Having carefully fitted the diaphragm and the magnet
M by its two brass plates n and p, all must be taken apart
again, temporarily, for the winding of the bobbins with
insulated wire. But before this is done the transmitter
claims attention. Although the transmitter unit (en-
closed in the wood disc c below) is contrived in so simple
a way, it is in all respects a reliable instrument of the
Hunnings-Deckert granular type in modern use.

The solid carbon block k, shown black, may be a 1 in.
square cutting from a broken battery carbon plate { in.
thick, with its angles removed by rubbing down on a
grit-stone doorstep or in a household sink of that material.
The rounding off of this block in this way may be rather
black and dirty work, but it is soon done, particularly if
plenty of water and some sharp sand are used to hasten the
grinding. The use of a grindstone much speeds up this
uncongenial job. The rounded block should be made a
push-in fit for the 1 in. hole in c ; if one of its faces can be
roughened by a number of parallel grooves scored across
the disc at right angles with each other, latticewise,
X 353

Every Boy His Own Mechanic

using an old rasp, file or saw-blade for the job, so much
the better ; but this is not absolutely necessary. When
finished, wash the block free from grit and dry it off
thoroughly by heating strongly in the oven.

Cut a 1 in. disc of tinplate or sheet brass, solder a length
of covered copper wire to its centre, wash, dry, polish and
then pass the wire end through the central hole and push
the metal disc to the bottom of the 1 in. cavity in c {see
Figs. 2 and 3). This is for the smooth side of the carbon
block K to bed upon, but to improve the electrical connec-
tion between the carbon and metal discs a pad made up
of several discs of tinfoil should be compressed between
them. Take the carbon block hot from the oven and
melt some pitch, marine glue or sealing-wax around its
rim (but not on its face or back) ; then quickly force the
hot carbon into the cavity, bedding it firmly on the tinfoil
and sheet metal discs and maintaining it under heavy
pressure until cold. A cardboard washer w^ is next
gummed to the face of c, just as was done in the case of
B (the receiver), but this inner washer of the transmitter
must be considerably thicker ; about -| in. or a little less.
The transmitter-diaphragm rf is a 2 in. diameter disc of
very thin carbon, which costs a few pence at any electrical
stores ; it is extremely delicate and brittle, and must be
handled daintily.

The space between the carbon disc d and the block k
is loosely packed with small dustless fragments of granular
carbon. This may be ground up from scrap, carefully
screened to size and sifted free of dust, but the specially
prepared article costs only a few pence per ounce (1 oz.
will be sulilcient lor two instruments), and this had better

354

A Practical Home-made Telephone

be purchased along with the diaphragms. To confine
the granules to the central areas of the disc and block a
circular bedding of soft cotton wool must be lightly dis-
posed over the face of c, within the washer w^ and ex-
tending inwards over the brim of the block-aperture, as
suggested by waved lines in Fig. 2, making a soft and
yielding nest, as it were, for the granules to lie in. The
delicate carbon disc d, when placed on the washer w,
should press down and gently confine the boundaries of
this wool nest, but it should bed firmly on the washer,
also, and the wool should not be so dense as to endanger
the carbon by any excessive strain.

The outer washer w may be of cardboard or it may be
a stout rubber ring. In either case, this washer must be
entirely enclosed in a covering of tinfoil. This is best
applied in very narrow strips wound over and under all
round the ring with the strip edges overlapping ; a mere
touch of gum may be used to secure this foil binding, here
and there ; but not too much, or the conductivity of the
metal sheathing will be lessened.

So much for the outer washer w, but before the parts
are assembled, the face of the inner washer w^ must also
be foil-coated. A plain washer of tinfoil gummed on will
do in this case, but it should be rather larger in diameter
than w^ (say 2 J in.), so that its margins will be compressed
into close metallic contact with the tinplate cover of the
transmitter when the latter is pushed on. Thus the carbon
disc d will be in good electrical connection with the outer
cover when nipped between the foiled washers w and w^,
and when all parts are in position the two wires passing
out to the back of the body will complete an electrical

355

Every Boy His Own Mechanic

circuit through the block k, the nested granules, and the
carbon disc d.

The central hole in the transmitter cover is fitted
with a cone of tinplate soldered on skewwise to form a
mouthpiece, and requires no further explanation.

To assemble, the granules are lightly strewn over the
roughened surface of k, within the wool nest, and the disc
d placed over them and gently pressed down. The disc
should slightly confine the grains, but it should bed on
the washer w firmly. Several tests must be made (when
all is finished) before the best quantity of grains for clear
speaking can be decided, and then the covers can be finally
pushed on and secured permanently by the three brass
pins around the rim.

Winding the receiver bobbins is a delicate job, but
perfectly simple if the utmost care be exercised. No
attempt should be made to wind by hand as it would
prove a waste of time and fruitful source of failure through
the tangling and snapping of the very fine-gauge wire
necessarily employed (No. 36 gauge). You must, there-
fore, knock up the little wooden windlass shown at Fig. 5a
with an axle ^ in. in diameter to fit the bobbin-bores
moderately stiffly; clamp this to the edge of the work
bench and mount the store-bobbin of insulated wire on a
bent wire " horse," as in Fig. 5b, driven into the same
at a convenient point. Turn the crank handle with the
right hand and guide on the wire with the left. Wind the
wire quite closely and evenly, as a reel of cotton thread is
wound ; do not allow spaces to appear between the coils ;
do not heap up the wire. As each layer is wound on
saturate it with paraffin wax applied in fragments and

356

A Practical Home-made Telephone

melted with the warmed blade of a blunted table-knife,
palette-knife, or putty-knife. Do not overheat the knife;
let it be warm enough to melt the wax freely, but not hot
enough to cause smoking. A very little wax will be found
sufficient to saturate the covering of the wire (turning it
to a darker shade of colour). Use no superfluity of wax
to cause lumps and irregularities. Interleave every
layer of wire with one lap of thin paper cut in strips the
exact width of the winding-spaces. Apply the paper to
the wire-layers (already waxed) by rubbing it down
gently with the warmed knife. The wax will saturate

Fig. 5a. — Windlass for
Winding Bobbins

Fig. 5b. — Store-reel mounted
on Wire Horse

the thin paper, also, when this is done, and it will adhere
closely and leave a smooth surface for the following layer
of wire. When the interleaf is taken once round, overlap
it very slightly (^ in. or so), tear off the surplus of the
strip, " sleek," down to the seam and proceed patiently
winding, waxing and interleaving until the bobbin is
nearly full.

In Fig. 2, the section shows the wire conventionally
by latticed lines ; only four layers are indicated, but in
practice there will be about fifteen layers to build up.
Every layer should have the same exquisite care bestowed
on its winding. It is slow and rather monotonous work,
and to hurry it leads to failure. Great patience must be

357

Every Boy His Own Mechanic

exercised, for there are several hours of work in each
bobbin.

Count the layers of the first bobbin and wind the
others with the same number. Wind all the bobbins in
the same direction on the windlass ; then, when the pairs
are mounted on the cores, it is only necessary to join
either both the outside ends, or both the inside ends, of the
windings together to obtain the correct S-wise circulation
around the cores. (Carefully note this.) The beginning-
end and the finishing-end of each winding may be passed
out through holes drilled in the bottom disc to be placed
nearest the yoke l. Alternatively, the beginning-end of
the wire may be " cemented " to the inner face of one
bobbin cheek with wax, and brought out sandwiched
between it (the bobbin-cheek) and a washer of waxed card
(the latter being cut through to the central hole to allow
it to be slipped over the bobbin-tube). The emerging
inner wire end will thus be insulated from the succeeding
coils by a waxed cardboard wall.

When fully wound, the external layer of wire miist be
enclosed in a protective sheath of two or three laps of
stout waxed paper well consolidated with the warmed
knife and smoothed down.

The bobbins may now be pushed on to the cores, their
inner winding ends snipped to an equal length, the ends
freed of insulation, cleaned, twisted together and soldered.
But note that soldering-fluid must not be used in this
case ; resin is the only safe flux for soldering electrical
wires. The two free wire ends should be similarly cleaned
and prepared for jointing, and then all parts of the hand-
combination can be put together as in Figs. 2 and 3. The

358

A Practical Home-made Telephone

handle connections are clearly shown by the black lines
in Fig. 3 ; these should be made with fairly stout wire,
say No. 22 gauge ; they may conveniently be laid in
grooves cut in the back of the wooden body a. The junc-
tion of the thin receiver-wires and the stouter ones may
be made by soldered joints, or by looping the ends of both
the thin and the thick wires under two brass washers
secured by mushroom-head screws at a convenient point,
say just within the loop of the magnet. This is not shown
in the illustrations, but the current-path is made quite
clear.

Starting from the left terminal screw and washer at the
lowest point of the transmitter (Fig. 3), one conductor
passes to the receiver-magnet and thence returns to the
transmitter - casing {see also Fig. 2), whence current
passes through tinfoiled washers zv and w'^ to carbon
diaphragm d, the granules (dotted), and the carbon back-
block k, to the right-hand terminal. (The grooves con-
taining the conductors can be filled in with shellac applied
with a heated iron.) One yard of twin-flexible telephone-
cord must be threaded through the small screw-eye, and
the bared end of each conductor neatly looped and screwed
down firmly under the terminals, left and right. This
completes the hand combination. Its total cost for
materials should not exceed 2s., or say 50 cents, even at
war-time prices. The requirements are 1 oz. of No. 36
gauge silk-covered wire (| oz. on each bobbin) ; carbon
diaphragm ; 2 in. magnet ; sundries, 4d., or say 8 cents.

The Wall-Sets. — Fig. 6 shows one of the wall-sets ;
it is designed to dispense with all ready-made electrical
parts, and only the wire for the bell-magnet (2 oz. of

359

Every Boy His Own Mechanic

No. 26 gauge, silk-covered) need be purchased. The
gong may be taken from a disused cycle-bell, or an efficient
substitute can be improvised by use of a wine glass with
a broken stem (which emits a clear and musical note).

The magnet m is
bent up, from a 4-in.
length of ^-in. common
wrought - iron " nail-
rod " and measures
IJ in. from the curve
to the pole ends, the
latter being spaced
about ^ in. to | in.
apart.

The bobbins b are
1 in. long by f in. in
diameter, made and
wound as already de-
scribed, but with about
1 oz. each of No. 26
gauge silk - covered
wire.

The armature is a
piece of strip wrought
iron about -^ in. to fin.

Fig. 6. — Details of Complete Wall-set.
(Scale, 6 in. = 1 ft.)

wide by -^ in. to A in. thick. The armature-spring a s
and the contact-spring c s are sheet brass hard-beaten
with a smooth-face light hammer on the surface of a
laundry-iron to make the metal springy, then filed and
glasspapered smooth and thin. (To make the drawing
clear their thickness is exaggerated.)

360

A Practical Home-made Telephone

The bell hammer is a bit of iron or brass rod filed round-
ended and soldered to a wire shaft, itself soldered into the
armature ; the spring a 5 is also soldered to the armature.

These springs are mounted, by one mushroom-head
brass screw each, on a rectangle of tough hardwood (such
as oak or beech), which is shown partly shaded. This is
drilled to receive two other screws (shown dotted), the
upper one 1 in. long and the lower one | in. long, with
their extreme points filed flat. These screws adjust the
stroke of the hammer on the gong ; the upper screw
advances the armature nearer to the magnet-poles, accord-
ing to the battery power available ; and the lower one
advances the contact-spring c s, so regulating the rapidity
of the hammer strokes. The wooden support of both
springs is attached to the baseboard by two more mush-
room-head brass wood-screws, the heads of which are
shown. Devised especially for this book, this form of
contact-breaker is really a better arrangement than the
usual one (requiring finished parts), the contact-point of
the springs being of the "rubbing" type which is self-
cleaning and requires no platinum facing. If, however,
some silver scrap is available it will repay the trouble to
solder a small cutting of silver to each contact-face.

The magnet is secured to the baseboard by a screw
passing through a wooden or metal cross-bar placed across
the bobbins, as at n (Fig. 2).

The push and automatic switch-hook movements are
also of original design ; both are bent up from lengths of
wire. That for the switchhook may be No. 12 gauge
hard brass, but the push-spring may be thinner. To
make them, drive nails or screws into the bench (or an
X* 361

Every Boy His Own Mechanic

odd piece of board) in the requisite jDositions and bend
the wires round the patterns (" jigs ") thus improvised.

For the switch-hook, take about 1 ft. to 15 in. of the
stouter hard brass wire, bend | in. of one end at right angles
and drive this into a hole in the bench {see x) about | in.
distant from the first jig-screw. Twist the wire round
this, one complete turn {see y), and round the second jig-
screw f in. farther on, one turn and a quarter {see z).
Now remove from the bench and bend the wire at right
angles about | in. distant from the % twist ; and at 3| in.
from this angle fold the wire closely upon itself {see hook) ;
and opposite the last right angle, bend once more at right
angles to form the right-hand |-in. extension shown.
The doubled portion of the wire may be soldered together
or not, at option, and when about 1| in. of the doubled
end is curved forward into a hook of about f in. semi-
diameter the fitting is complete. It is mounted by driving
its |-in. spur x into the baseboard and securing eyelet y
down upon a brass washer by a mushroom-head wood-
screw. A bone games-counter may be tacked to the
baseboard under the spring eyelet z and counters (or
rectangular cuttings from the same) may be drilled to go
under the (easily driven) staples s, which keep the hook-
switch in position, but allow it free movement up and
down between the contact-pegs c and d. For clearness,
the drawing shows the contact end of the switch midway
between pegs c and d ; but in practice the spring is given
a strong bias upward, so that it always presses hard
against the d peg until the hand-combination telephone
(Figs. 1, 2 and 3) is suspended on the hook, which removes
the contact-end from d and carries it to rest firmly on c.

362

A Practical Home-made Telephone

The push-spring is on identically the same principle
as the switch-spring, but simpler and of lighter gauge
wire ; it is secured by its spur (like x), one screw (like y),
and a staple (s). Its permanent spring-bias keeps it
hard against peg a, but when it is pressed to the left {see
arrow) it makes contact with b.

The two little double-screwed fittings 4, 4S on the
left side of the board are connections for the ends of the
telephone-flexible, and the three terminals, 1, 2 and 3, at
the top of the board, are mushroom-head wood-screws
passed through brass washers. All the baseboard con-
nections should be of No. 22 gauge copper wire laid in
grooves at the back. They need not follow the routes
shown by the broken lines, but may take any other direc-
tion found to be more convenient, provided that they do
not touch each other at any point or crossing.

The contact-pegs a, b, c and d may be of stout brass
wire with a few inches of No. 22 gauge wire soldered into
small holes drilled in their ends ; alternatively, the wires
may be soldered to flats filed on the peg-stems. (If all
the contact points can be sheathed with silver-scraps,
soldered on, so much the better ; but this is not essential,
as the parts are easily accessible for cleaning.) The pegs
being driven partly through the baseboard, their thinner
wire extensions can be neatly bent down into the grooves,
previously cut, and either carried along them and through
small holes to the washers, etc., on the front of the board,
or, soldered (in the grooves) to the ends of other wires
brought half-way to meet them. (All joint soldering must
be done with resin and no other flux.)

The curved broken lines so clearly indicate the base-

363

Every Boy His Own Mechanic

board connections that it is necessary only to explain the
current paths between the two stations when ringing-
calls are sent or conversation is exchanged. As shown,
the baseboard measurements are 6| in. by 4 in. ; the com-
pleted wall-sets should be provided with outer casings of
thin fretwood or of tinplate mounted on wood fillets, to
preserve the mechanism from dust and tampering fingers.
A central orifice backed by a piece of wire gauze will let
out the sound of the gong. This suggestion is embodied in
Fig. 7, which shows the external wiring to the batteries
and lines complete.

Conclusion. — A complete understanding of the whole
installation will best be obtained by a systematic trace-out
of the current paths, to which end Figs. 6 and 7 must be
studied. Let it be assumed that station a is calling
station b (Fig. 7). a's push is pressed to the left and
current from the carbon (-|-) of the A-battery flows by
terminal 2 {see Fig. 6) to stud h of the push (pressed to the
left) and through its spring to stud c of the switch (which
is down because the telephone hangs on the hook) and so
to screw y and terminal 1. Thence {see Fig. 7) it travels
by line to terminal 1 of station b and to screw y {see Fig.
6) and the switch-hook {down), stud c, the press-spring
(biased to the right) and stud a, through the magnet-
coils B, springs a s and c s (ringing the bell) to terminal 3
and back to the zinc (— ) (Fig. 7) of the sending-battery
at the A station, by the return line. Thus a can call up
B, and B can call up a similarly, a and b now lift their
telephones from the hooks, and the switch springs rise
breaking contact with studs c, and making contact with
studs d. Current now passes continuously through both

364

A Practical Home-made Telephone

telephones and both batteries in series, and the bell-
circuits are cut out completely. Starting, say, from + of
the A battery (Fig. 7), current flows by terminal 2 to con-

/i 77e

7*&tu 7*77

Fig. 7. — System of Connections

or External Wiring for the

Telephone Installation

nection t {see Fig. 6) and by one conductor of the twin-
flexible through the transmitter and receiver of the hand-
telephone {see Figs. 1, 2 and 3) and back by the other
conductor of the flexible to connection t^ (Fig. 6), to
stud d, the switch {up), screw y, to terminal 1 and thence
by line to terminal 1 of station b (Fig. 7) to screw y (Fig.

365

Every Boy His Own Mechanic

6), the switch hook (up), stud d, connection t^, the tele-
phone, connection t, and terminal 2. Then down to the
zinc (— ) of the b battery (Fig. 7) through it to +, and
(reinforced in power) back by the return line to the zinc (— )
of the A-battery from which this series-trace commenced.
Well, there you are, dear fellows ; the simplest tele-
phone in the world has been designed and described for
you. Simple though it be, and within reach of the shallow-
est purse, it is no toy or makeshift, but the real thing,
capable of conveying clearly and reliably the most im-
portant conversation that ever passed over wires between
the two " biggest pots " on earth. Listen ! The writer
hails you — " Are you there ? " — " Au revoir ! "

366

INDEX

Accumulators, 41-43
Aeroplane, Model, 319-377

, Toy, 143-147

Aluminium, 80
Aluminium Bronze, 80

, Soldering, 80

Amalgamating: Battery Zincs. 112,

121
Amperes, 43
Aniline Stains, 158
Annealing Steel, 11
Applique, Fretwork, 171
Aqua Regia, 79
Aquarium Cements, 38, 39
Archimidean Drills, 165
Ash, 342

Batteries, Dry, 49, 50

, Making, 111-124

, Position of, 50

, Primary, 41-43, 45

, Renewing, 59

, Secondary, or Accumulators,

41-43
Battery Zincs, Amalgamating, 112,

121
Bearers, Shelf, Erecting, 330-332
Bearings (see " Bicycle Bearings ")
Beech, 342
Bell (see Electric)
Bench, Pretworker's, 164

Hook, 13

, Kitchen Table as, 1-4

, Metalworker's, 94

Screws and Their Fixing, 2-4

, Woodworker's, 1-6

Bevel, Sliding, 9

Bichromate Battery, 117

Bicycle Bearings, Adjusting, 177-178

, Cleaning, 177

: Renewing Balls, etc., 177-

179

Bottom Bracket, Taking Apart,

178

Chain, Adjusting, 184

, Cleaning and Lubricating.

179

, Effect of Worn, 180

in Gear-case. 180

, Removing, 179

" Chain Line," 182

Coaster Hub, Cleaning, 183

Cotters, Removing, 178

Covers, Removing, 185, 186

, Repairing. 188

, Replacing, 189

Bicycle Cranks, Removing, 178

Frame. Cleaning, 1Z6

. Enamelling. 176, 177

: Frame Size, 182

Free-wheel Clutches, Cleaning,

, Renovating, 183

, " Gear " of, 174, 175

, Parts of, 172-174

Pedals, Removing, 182

' Plated Parts, Renovating, Lac-
quering and Protecting, 184,
185

Spokes : Adjusting Tension, 181

"Tread," 182

Tubes, Patching, 186-188

, Testing, for Punctures, 186,

188

Tyre Stopping, 188

Tyres, Removing, 185, 186

, Replacing, 189

Valve, Testing, 183

Variable-gear, 175

" Wheel Base." 182

Wheels Out of Truth, 180-182

Biscuit Barrel, Cementing Rim on, 35
Bit, Soldering, 127

, , Heating. 128, 129

, , Tinning, 130

Blowpipe Flame, 133. 134

Moulds, 309, 313-315

Soldering, 134

, Lamp for, 134

Boat, 10-ft Flat-bottomed Rowing,
307-319

Bottom Planking, 314. 315

Chines, 314

Fittings, 318

■ Floor, 316

Keel Piece, 315

Moulds, 309, 313-315

, Painting, etc., 318

Seams, Caulking, 317. 318

Seats and Supports, 316, 317

Side Planking, 311-313

, Bending, 313

Rubbing Pieces, 315, 316

Stems or Stemposts, 310

Uprights, 314

Boiler, Model, Silver-soldering, 135-
137

of Model Locomotive, 214

Bow-saw, Using, 275

Brace, 7

Brackets, Enlarging Screw Holes in,

334
Bradawl, 9
Brass, 76

Broach or Reamer, 104, 334
Bronze, 76

367

Index

Bronze, Special, 76, 80
Brushes, Glue, 106
— . Paint, 153, 154
Bunsen Battery, 116

Calipers, 224

, Using, on Lathe Work, 224

Candle-power, Electric, 44
Canvas, Waterproofing, 268
Carrier, Lathe, 283
Caulking Boat Seams, 317, 318
Cells (see Batteries)
Celluloid, Cementing. 36-38
, Dissolving, 36, 37

Films, Repairing, 37, 38

Lacq^uer, 185

, Testing, 36

Cement, Portland, Using, 40

: Rubber Solution, 187

, Water-glass, 38

Cementing Aquariam, 38, 39

Celluloid, 36-38

China, 38, 39

Cinematograph Films, 37, 38

Glass, 38, 39

Rims on Various Vessels, 35

Tyres on Rims, 39

Xylonite, 36

Centre Bit, 9

Chain (see Bicycle Chain)
China, Cementing, 38
Chisels and Their Use. 27-33

, Metalworker's, 101

, Sharpening, 19-22, 28, 29

, Woodturner's, and How to Use

Them, 221, 225. 226
Chucks, Metal-turning, 282

, Prong, 222, 223

, Screw, 227-229

Compasses^ Wing. 9
Concrete Floor, 40
Copper, 78

Cotters, Removing. 178
Cramp, 5-7

for Picture Frames, 89

, Rope, 108

, Wedge, 108

Cutting-board, Fretworker's, 164
Cycle (see Bicycle)

Daniell Battery, 117

Designs, Applying, 286

, Fretwork. 163, 166. 167. 158. 170

Picture-frame, 85. 88, 90

, Reversing, 286

, Transferring, 168

Dog Kennel Built in Sections, 289-
297

, Lathe. 283

Dory, Boat Adapted from, 309
Dovetail Angle, 271, 272

, Box or Common, 276-280

, Half-lap, 270-275

, Single, 270-275

Templates, 271, 278

Dowel, 139

Draw-boring, 202, 203

Draw-filing, 97, 98

Drill, Archimidean, 103, 165

, Flat or Diamond-point, 102

. Hand, 7

, Metalworker's, 102

, Straight-fluted, 103

, Twist, 102

Dry Batteries, 121-124

Electric Batteries, Making, 111-124
(see also Batteries, Bichro-
mate, Bunsen, Flash-lamp,
Leclanche, ■ Wollaston, etc.)

Bell Circuits, 45, 46, 50, 54-56

Faults, 68

: How It Works, 51

Wire and Wiring, 50, 61-64

Circuits, " Earthed," 56, 57

. Gas-pipes included in, 56,

Connections : Parallel, 48, 55

: Series, 47, 48

: Series-parallel, 48, 49

Lamp, 44

Wire and Wiring, 50, 61-

Circuits, 45, 46, 50, 54-56

Lampholder, Construction of, 59

. Wiring-up, 59

Light Batteries, 41-43

Push. 52

Signalling System. 56

Switches, 53, 54

Twin-flexible Cable, 58, 60. 62

Wires. 50, 61-64

, Clipping, to Pipes. 63

. Jointing, 57

. Screw-eyes for. 63

, Staples for. 62

Electrical Terms : Amperes. 43

: Candle-power, 44

: Ohms, 43

: Volts, 43

: Watts, 44

Ellipse, Setting-out, 234, 235
Elm, 342

Enamel, Cycle, 176

Paint, 156

, " Flat " and Glossy. 157

Undercoating. 157

Enamelling, 156-158

Bicycle Frame, 176, 177

, Brushes for, 157

Engravings, Mounting, 231

Ferret Hutch, 260-262
Files Becoming Pinned, 76

. Cutting Glass with, 91

for Saw-pierced Work, 288

, Grades of, 97

, Hardening, 91

. New. Using, 78

, Single-cut and Double-cut, 98

, Swiss, 97, 98

, Various Shapes of, 96, 97

368

Index

Filing, 98, 99

, Draw, 97, 98

Flash-lamp Batteries, 121-124
Floor, Concrete, 40

Staining. 160

Flour Paste, Making, 231
Flux, Soldering, 126, 127. 135
Fox-wedging, 201

Fuming Oak, 159, 160

Frame (see also Picture Frame)

, Glazing, 70-73

, Three Sizes of, 71

Free-wheel, Cleaning, etc., 183
French Bunsen Battery, 112
Fretsaw Frames and Blades, 162, 164

, Metalworker's, 285

, Using, 168, 169

, Wood and Metal, 285

Pretwood, 166, 167

Fretwork Cutting Board, 164

Designs, 163, 166, 167

, Laying Down and Trans-
ferrins'. 168

Drill, 165

, Finishing, 170

, Glasspapering, 165, 166

in Metal and Ivory, 285-288 (for

details, see Saw-piercing)

Marquetry, 169, 170

Overlays and Applique, 169-171

Table or Bench, 164

in Wood, 161-171

Graver, Metal turner's, 281
Grenefs Flash Battery, 117
Ground-sheets, Waterproofing, 268
Gunmetal, 76
Gynast, Toy, 138-143

Hack Knife, 70

Saw Frames and Bla4es, 95-97

, Using, 96

Halved Joint, Making, 13, 30-32
Hammers, Metalworker's, 100

, Wedging Heads on Shafts, 100

, Woodworker's, 7, 100

Hand-combination (see Telephone)

Hand-drill, 7

Handscrew, Wooden, 7

Hard Soldering, 135-137

Hardening and Tempering, 76, 91,

100
Hektograph, Making, 65, 66

Ink, 67

— , Putty, 68, 69

Tray, 66, 67

— , Using, 67, 68

Holes, Enlarging, in Brackets, etc.,

334
Hook, Bench, 13
Hutch, Ferret, 260-262
, Rabbit, 255-260

Garments, Waterproofing, 268
Gauge, Marking, 9

, Rail, 305

Gilder's Cushion, 190

Knife, 190

Oil Gold Size, 191

Tip, 190

Gilding with Gold Leaf, 190

Gimlet, 9

Glass, Cementing, 39

, Cleaning, 92

, Cutting, 91

Pane, Inserting, 70-73

Plates or Hangers, 334

, Qualities and Weights of, 72

Silvering, 263. 267

Glasspapering Fretwork, 165, 166
Glue, Liquid, 110

, Preparing, 105, 106

, Seccotine, 109

, Waterproof, 109, 110

Gluing Joints. 107

Picture Frames, 89, 90

Gluepots and Brushes, 105, 106
Gold, 81

Leaf, 190

, Gilding with, 190-192

, Transfer, 192

Lines on Mounts, 235, 236

Paint. 192, 193

- Medium, 192, 193

Gtold-bronze, 192, 193
Gouges, Sharpening, 22, 23

, Woodturner's, and How to Use

Them, 221-225

Ink, Hektograph, 67

Inkstand, Cementing Rim on, 35

Iron. Cast. 74, 75

, Wrought, 75, 76

Ivory, Distinguishing, from Cellu-
loid, 36

Joint, Dovetail, 270-280

, Halved, 13, 30-32

, Mortise-and-tenon, 194-203

, Pinned, 202, 203

. Wedged, 200-202

Kennel Built in Sections, 289-297
Kldd, Mr. D : Design for Boat, 307
Killed Spirit, Preparing, 126
Knife, Gilder's, 191

. Hack, 70

, Mount-cutter's, 223

, Putty, 70

Lacquer, Celluloid, 185
Lacquering Cycle Parts. 184, 185
Lamp (see also Electric)

for Soldering. 134

Reservoir, Cementing Rim on,

36
Larch, 342
Lathe (see also Metal-turning and

Wood-turning)

369

Index

Lathe, CJomponent Parts of Simple,
219-221

Dog or Carrier, 283

Tools, 221

Lead, 79

Leclanch6 Battery, 111

, Charging, 111, 115

, Sack. 112-115

Zincs, Amalgamating, 112,

121

Lighting (see Electric)

Liquid Glue, 110

Locks, Cleaning, 334, 355

, Renewing Springs of, 336

Locomotive Bogie, 213, 214

Boiler, 214

Boiler-bands, 217

Buffers and Hooks, 217

, Cardboard Model, 204-218

Coupled Wheels, 213

Coupling-rods, 217

Dome, 215

Funnel, 215

Hand-rails, 217

Main Frames, 211

, Model : Gauges and Scales, 206-

208
, Procedure in Making, 217

Tender, 216

Wheel Arrangement, 204, 206

Wheels, 210

Mahogany, 342

Stain, 159

Maple, 342

Marking Awl and Knife, 9

Gauge. 9

, Using, 276

Marquetry, 169, 170
Metals, 74-81
Metal-turning, 281-284

: Bar or Spindle, 282-284

Chucks, 282

, Graver for, 281

Rest, 282

Tools, 281

Methylated Spirit, 158

Microscope Speculum, Silvering, 263-

267
Mirror Making, 263-267
Mitre-block, 84
Mitre-box, 83
Mitre-shoot, 86-88
Mitre-trimmer, 89
Model Aeroplane, 319-327

Locomotive Gauges and Scales,

206-208, 298, 299

. Making. 204-218 {for details,

see Locomotive)

Railway : Laying the Rails,

298-306
Monoplane, Model, 319-327
Mortar, Cement, 40
Mortise-and-tenon Joints, 194-203
Mortise, Closed, 198-200

, Open, 194-198

Moulding Machine, Spindle, 82
Moulds, Boat, 309, 313-315

Mount Cutter's Knife, 233

Cutting, 233, 234

, Gold Lines on, 235, 236

, Oval, 234, 235

, White Lines on, 235, 236

Mounting Pictures, 231-233

Nails, 328

, Inserting, 328, 329

in Walls, 330

, Wire, 328

Oak, 342

, Fuming, 150

— - Stain, 159

Ohms, 43

Oil, Double-boiled, 268

Gold Size, 191

, Waterproofing with, 268. 269

Oilstones, 20

Oval, Setting Out, 234. 235

Overlays, Fretwork, 169

Packing-cases Made into Hutches,

255-260
Paillons of Solder, 135
Paint Brushes, 153, 154, 157

, Buying, 154, 155

, Composition of, 155

, Enamel, 156

, (Jold-bronze, 192, 193

Painting, 153-156

: Stopping, 156

Pane of Glass, Inserting, 70-73

Panel Pins, 328

" Parallel " Electric Connections, 48,

56
Parting Tool, 227
Paste, Flour, Making, 231

for Metal, 285, 286

Patterns (see Design)

Pedals, Bicycle, Removing, 182

Pen. Ruling. 236

Pepperpot, Cementing Rim on, 35

Phosphor-bronze, 76

Picture Frame Backboard. 92

, Cramping, 89, 90

Designs. Various. 86. 88, 90

, Estimating and Cutting

up Material for, 84, 85

, Finishing, 92, 93

, Fitting Up, 90-93

Glass, Cutting, 91

, Size of, 72

, Gluing Up, 89, 90

Making, 82-90

Mitres, Cutting, 86

. Shooting, 86-89

, Strengthening, 90

Mouldings, 82, 83

g, — , Three Sizes of, 84

, Tools, etc., for Making, 83,

Pictures, Mounting, 231-233

370

Index

Pincers, 9

Pine, 342

Pinned Woodwork Joints, 202, 203

Pins, Panel, 328

Plane, Action of, 18

Iron or Cutter, 17

, Sharpening, 19-22

, Jack, Using, 24. 25

, Kinds of, 15

, Putting Together, 23

, Smoothing, Using, 25, 26

, Taking Apart, 15-18

Platinum, 81

Plating, Battery for, 115-118

Plugging Walls, 330, 331

Points, Model Railway, 303-306

Polishing Work in Lathe, 226, 227

Portland Cement, Using, 40

" Pouncing " Designs, 286, 287

Prints, Mounting, 231, 232

Prong Chuck and How to Use It,

222 223
Propeller,' Model Aeroplane, 320, 322
Pushes, 52, 362
Putty Hektograph, 68, 69

Knife, 70

, Removing Old, 70

Stopping, 156

Rabbit Hutch, 255-260

Rails : " Between - tyre - dimensions,"

299. 304

: Frogs, 303-306

, Gauge for, 305

, Laying, for Model Railway, 298-

306

, Materials for, 301

: Points, 303-306

: Setting Out Curves and Points,

304

, Sleepers for, 302

, Wing and Check, 303

Railway (Model) Gauges and Wheel

Dimensions, 206-208, 298, 299
Reamer, 104, 334
Rowing Boat, 307-319 [for (UtnUs,

see Boat)
Rubber Solution, 187
Ruling Pen, 236

Sal-ammoniac Block, 130

Sash, Window, Loosening Stuck, 339

Saw, Fret. 162, 164, 285

, Hack, 95-97

, , Using, 96

. Hand, and How to Use It, 8-12

, Tenon, and How to Use it. 8,

12-14

, Various Kinds of, 7. 9

Sawing, 8-14

in the Waste, 14

, Rip, 11

Saw-piercing : Applying Design, 286

: Files, 288

: Finishing. 288

: Metal, 285-288

Saw-piercing : Paste, 285, 286

:" Pouncing," 286, 287

: Saws and Frame, 285

: Working the Saw, 287

Scrapers, Metalworker's. 99

, Using, 100

, Woodworker's, Sharpening and

Using, 26, 27
Screw Chuck, 227-229
Screws, 328

, Bench, and Tlieir Fixing, 2-4

, Damaged, Removing, 33

, Rusted-in, Removing, 34

Screwdrivers, Selection and Use of,

9, 33, 34
Screw-eyes for Electric Wires, 63
" Series " Connections, 47, 48
" Series-parallel " Electric Connec-
tions, 48, 49
Shelf, Erecting, 330-334
Shooting Board, Mitre, 86-88

Edges, 276

Silver, 80, 81

, Saw-piercing, 288

Soldering, 135-137

Silvering Glass, 263-267
Sleepers, Model Railway, 302
Sliding Bevel, 9

Solder, Silver, 135

, , Cutting Up, 135

, Soft. 125, 126

, Tinman's, 125, 126

: " Tinol " or " Bri-tinol," 126

Soldering, 125-137

Aliiminium, 80

Bits, 127

. Heating, 128, 129

, Tinning, 130

, Blowpipe, 133, 134

, , Spirit Lamp for, 134

Electrical Wires, 57

Flux, 126, 127

:"Fluxite," 127

, Hard, 135-137

"Iron," 125, 127

-: "Killed Spirit," 126

: Necessity of Clean Surfaces,

129, 130

Patch on Vessel, 131

. Silver, 135-137

, , Flux for, 135

, , Outfit for, 136

, : Pickle, 136

, Soft, 125-134

: "Sweating," 132

Solutions, " Saturated," 35
Speculum, Silvering, 263, 267
Spindle Moulding Machine, 48
Spirit Lamp for Soldering, 134

, Methylated, 158

Spokeshave, 7

Springs, Lock, Renewing, 336

Spruce, 342

Stain and Varnish Combined, 160

Stains, Aniline, 158, 159

, Various, 159

Staining, 158-160

Floors, 160

: Fuming. 159, 160

Staples for Electric Wires, 62

371

Index

steel. Annealing. 77

, Blister. 77

. Cast. 76-78

, Hardening, 76

, Mild. 76

, Tempering, 76

. Tool, 76-78

Stopping. Painter's. 156

, Tyre, 188

Sweating a Soldered Patch, 132
Switch-hook, Telephone. 362
Switches, 53, 54

Table Adapted as Bench, 1-4

, Fretworker's, 164

"Tank." Toy, 147-152

Tap, Renewing Washer in, 337-339

Tapers, Turning, 229, 230

Teak, 342

Telephones, Hand-combination, with
Two Series-type Wall Sets,
How u) Make, 343-366

Telescope Speculum, Silvering, 263-
267

Tent Canvas, Waterproofing, 268

Tin and Tinning, 79

Tinplate. 79

Tool Handle, Turning, 221-227

Sets, 6

Tools. Fretworker's, 162-166, 285

, Metalworker's. 94-104

, Woodworker's, 6, 7, 9

Toy Aeroplane, 143-147

Gymnast, 138-143

"Tank," 147-152

Trammel. Using, 304
Transmitter, Telephone, 353-357
Try-sqnare. 9

Tube, Silver-Boldering. 135-137
Turning (see Metal-turning and

Wood-turning)
Tyre. Cementing, to Rim, 39, 40

Removing and Replacing, 185,

186, 189

Repairing, 186-188

Stopping, 188

Twist Bit. 9

Drill. 102

Vertical Spindle Machine. 82
Vice. Metalworker's. 94

. Woodworker's. 2-4

Volts, 43

Walls. Nails in. 330
, Plugging, 330, 331

— ', We
, Tu

Walnu.t, 342

Stain, 159

Washers, Tap, Renewing, 337-339
Water-glass Cements, 38
Waterproofing with Oil. 268. 269

Soap, 269

Watts 44

Wedging Woodwork Joints, 200-202

Wheel Rims, Cementing Solid Tyres

to, 39, 40
White Lines on Picture Mounts, 235,

236
Window Pane, Inserting, 70-73

Sash, Loosening Stuck, 339

Wollaston Battery, 118
Wood, 340-342

, Buying, 341

. Fret, 166, 167

-, Two-ply, Three-ply, etc.. 167, 340
Tarping of, 340, 341
[burner's, 229

, Various, 343

Wood-turning : Centering Work, 222

: Chucking Work, 222. 223

: Face-plate Work, 228

Lathe. 219-221

: Polishing Work, 226. 227

— — , Prong or Horn Chuck for, 222
— : Screw Chuck Work. 227-229

: Tapers. 229, 230

: Tool Handle. 221-227

, Tools for. 221

Using Callipers. 224

Chisel. 225, 226

Gouge, 223, 224

Parting-tool. 227

Various Examples, Z27, 228

, Woods for, 229

Woodworking : Bench. 1-6

: Chisels and Their Use. 27-33

: Draw-boring. 202, 203

: Halved Joints, 13, 30-32

: Mortise-and-tenon Joints. 194-

203

: Nails and Screws. 328

: Pinned Joints, 202, 203

: Planes and Planing, 15-26

: Saws and Sawing. 8-15

: Sharpening Edge Tools, 19-22,

28, 29

: Tools, 6, 7, 9

: Wedged Joints, 200-202

Xylonite (see Celluloid)

Zinc, 79, 80

, Amalgamating, 112, 121

Printed by Cassell & Company, Limited, La Belle Sauvage, London, E.C.4

50.219

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