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B1. Forging a chisel for stone working

Step 1: Cut an octagonal piece of steel (length approx. 6 3/8 inch / 16.2 cm, diameter approx. 5/8 inch / 1.58 cm). Heat one end to straw yellow, then round conically to an end diameter of approx. 0.5 cm/ 3/16inch (cf. fig.1).

Step 2: Heat the other end to straw yellow and forge it into a flat point as shown in picture 2. About 1/4 inch of this point should protrude over the edge of the anvil. The finishing touch can be made with a set hammer just above the refining temperature. If the point is forged at too low a temperature, the metal structure will be torn.

Step 3: The protruding end "A" is cut off completely or partially with a chop hammer. In the latter method, the protruding tip is broken off after hardening. The metal structure exposed in this way can be used to observe whether the temperature was correct during hardening. If the tip of the chisel has been hammered out too thinly, it must not be pushed back (risk of damage to the metal structure), but the tip must be cut off further back.

Step 4: The chisel must be cooled slowly so that internal stresses can be relieved. The cutting edge is tempered to a colour of blue, blue/red. Then the cutting edge is ground to an angle of 60° on a grinding wheel.

Source: Elementary Forge Practice, Robert H. Harcourt / Publisher Stanford University Press, 1917