This will leave
a clear hole, 7/8 in. in diameter, or a hole drilled the desired
size in a piece of iron plate will do as well. Countersink the top
of the hole so that the full diameter of the countersink will be
1-1/4 in. This completes the die. The punch A, is made of a piece
of 5/8 in. round iron, slightly rounded on the end so that it will
not cut through the metal disk. The dimensions shown in Fig. 1 can
be changed to suit the size of the finger to be fitted.
The metal used should be about 1/16 in. thick and 1-1/4 in. in
diameter. Anneal it properly by heating and plunging in water. Lay
it on the die so that it will fit nicely in the countersink and
drive it through the hole by striking the punch with a hammer.
Hold the punch as nearly central as possible when starting to
drive the metal through the hole. The disk will come out pan
shaped, C, and it is only necessary to remove the bottom of the
pan to have a band which will leave a hole 5/8 in. in diameter and
1-1/4 in. wide. Place the band, D, Fig. 2, on a stick so that the
edges can be filed and rounded to shape. Finish with fine emery
cloth and polish.
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