[Illustration]
Wrenches are used for screwing nuts on bolts. They can be made in two
ways: (1) One known as the solid wrench is made without welding, (2)
the other, is made of wrought iron and is welded.
_S wrench of soft steel:_ The sketch here is of a wrench made from
soft steel 1/2 × 1 × 5 ins. Fuller down the stock edgewise as shown.
Draw out the centre 1/4 in. thick and taper it from 3/4 to 5/8 × 5 ins.
long. Cut the corner off, as shown by the dotted lines, and round the
two ends up to the size given. Punch a 1/2-in. hole in the large end
and a 3/8-in. hole in the small end of the bar. With a sharp chisel cut
a V-shaped plug out of each end, tangent to the circles.
[Illustration: Wrench hardie]
_Jaws:_ The jaws of the wrench are finished with a tool called a wrench
hardie, placed usually on the anvil for the purpose of finishing up
work of this kind. Finish up both ends in the same way. Heat the wrench
at the nick and cool the jaws off in water. Place the nick on the horn
of the anvil and bend it as shown. Repeat on the other end. If the
wrench is carefully made it will require no filing to fit the nut.
These wrenches are sometimes polished and case hardened to prevent the
jaws from wearing while in use.
_Large flat wrench:_ A quick way to make a large wrench is to make it
of wrought iron. A piece of iron 1 × 1/2 × 4 ins. is bent at almost a
right angle. The inside corner is the corner made by the natural bend
the metal takes when shaping it.
[Illustration: Wrenches]
Scarf this corner by placing the peen of the hammer on the corner and
striking the face of the hammer with the sledge or by using a bob punch
if one is available, or it may be made by using the peen of the hammer
without the use of a helper. Select a piece of round iron 7/8 in. in
diameter. Upset the end of this and scarf it to fit the scarf made in
the angle piece. Heat both pieces to a welding heat. Place them on the
anvil and weld the handles to the jaws. The inside is rounded up at the
same time the scarfs are being welded into place. Draw the points out
to a short taper and bend them up in the shape of a wrench on the heel
of the anvil. This is a simple way of making a large wrench that can be
used for all kinds of work.
[Illustration: Alligator wrench]
_Alligator wrench:_ Stock 1 × 1/2 × 5 ins. steel. The alligator wrench
is one of the handiest tools to have in a home or shop. For general
repair work it is indispensable and is easily made. Mark off 1-1/2 ins.
from the end of the stock. This is the jaw part. Place the other end of
the stock in the fire. Take it out and from the centre-punch mark draw
the handle out 3/4 in. wide, 3/8 × 8 ins. long, and tapering to 3/8 ×
1/4 in. at the extreme end. The edges of the handle should be rounding.
Place the jaw ends in the fire and heat red hot. Punch 1/4 in. hole
back 1-1/2 in. from the end. Draw out the end and shape as shown in
the drawing. With a three-cornered file, file the teeth on a slant and
close together. This slanting will allow the wrench to let go of the
work better than those filed at right angles to the axis of the piece.
The teeth should slant backward and should be put only on one side of
the jaw. Both jaws should be hardened and tempered a blue colour. To
do this, heat the body of the steel back of the jaw to a red heat and
plunge the whole into water one inch beyond the depth of the jaw. When
cold take it out and polish. Draw the temper in the same way as you
would for a knife blade. (See article on tempering and hardening.)