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C2. Forging a stone drill with cross cutting edge

Step 1: Cut an octagonal piece of steel (length approx. 20 inch / 50.8 cm, diameter approx. 3/4 inch / 1.9 cm).

Step 2: Heat one end, then compress it to a diameter of approx. 1 1/10 inch / 2.8 cm with a set hammer.

Step 3: Use a drop hammer to hammer small grooves on 4 sides. These grooves have a length of 2 1/4 inches / XXcm). Their function is to hold and guide the upper and lower V-shaped die tools.

Step 4: Deepen the grooves with the die tools (fig. C2a). The drill must be turned regularly during this work so that the grooves become evenly deep.

Step 5: The resulting wings of the cross are now forged thinner on a "wing swage" (fig. C2b) with a rectangular set hammer. The end of the drill is scraped off at right angles with a very thin hot chisel.

Step 6: Shape the drill edges as shown in picture 6.

Step 7: Continue shaping the cutting edge with a "counterholder" (fig. C2c). This counterholder is either placed on the anvil and the drill is knocked into it, or the counterholder is held directly on the drill and hit with a sledgehammer. The cutting edge can be sharpened with a file while the tool tip is still hot.

Step 8: The annealing colour should be a dark straw yellow.

Quelle: Elementary Forge Practice, Robert H. Harcourt