m 1,800
to 2,000 deg.F. and forge thoroughly and uniformly. If the forging
operation is prolonged do not continue forging the tool when the
steel begins to stiffen under the hammer. Do not forge below 1,700 deg.F.
(a dark lemon or orange color). Reheat frequently rather than prolong
the hammering at the low heats.

After finishing the forging allow the tool to cool as slowly as
possible in lime or dry ashes; avoid placing the tool on the damp
ground or in a draught of air. Use a good clean fire for heating.
Do not allow the tool to soak at the forging heat. Do not heat any
more of the tool than is necessary in order to forge it to the
desired shape.

CARBON TOOL STEEL.--Heat to a bright red, about 1,500 to 1,550 deg.F.
Do not hammer steel when it cools down to a dark cherry red, or
just below its hardening point, as this creates surface cracks.

OIL-HARDENING STEEL.--Heat slowly and uniformly to 1,450 deg.F. and
forge thoroughly. Do not under any circumstances attempt to harden
at the forging heat. After cooling from forging reheat to about
1,450 deg.F. and cool slowly so as to remove forging strains.

CHROME-NICKEL STEEL.--Forging heat of chrome-nickel steel depends
very largely on the percentage of each element contained in the
steel. Steel containing from 1/2 to 1 per cent chromium and from
1-1/2 to 3-1/2 per cent nickel, with a carbon content equal to
the chromium, should be heated very slowly and uniformly to
approximately 1,600 deg. F., or salmon color. After forging, reheat
the steel to about 1,450 deg. and cool slowly so as to remove forging
strains. Do not attempt to harden the steel before such annealing.

A great deal of steel is constantly being spoiled by carelessness
in the forging operation. The billets may be perfectly sound, but
even if the steel is heated to a good forging heat, and is hammered
too lightly, a poor forging results. A proper blow will cause the
edges and ends to bulge slightly outwards--the inner-most parts
of the steel seem to flow faster than the surface. Light blows
will work the surface out faster; the edges and ends will curve
inwards. This condition in extreme cases leaves a seam in the axis
of the forging.

Steel which is heated quickly and forging begun before uniform
heat has penetrated to its center will open up seams because the
cooler central portion is not able to flow with the hot metal
surrounding it. Uniform heating is absolutely necessary for the
best results.