How to make your own concave punch.
I bought a set of diamond coated burrs From the Contenti Co. (800 343
3364) for $13.50 …about 12 different style burrs… then i took a
cement nail , ground the tip flat on a grinding wheel. Afterwards, I
put the nail in a flex shaft machine and held a round diamond coated
burr against the flat , Ground Area. In a short while, a depression
was formed and I continued to hold the burr against the nail until
the deppression was deep enough for my purposes.Getting the burr on
center is the most important part, then grind the outer edge of the
nail down until you have the correct exterior taper so it will clear
other parts of your design. Presto, you now have a concave punch.
It is not neccessary to harden the cement nail as it is already
hardened and this will work for a quite longtime.I have made a few
different punches , some that are mounted in a drill press and used
to rivet hinges and others that I use to set bezel and prong set
stones( not always in a drill press) .I have also used carbide burrs
Instead of diamond burrs to do the same thing .
The Diamond burrs are also quite handy to have around as they can be
used to Grind and shape other metal parts made of steel and you can
sharpen your small rubber wheels on them without loosing their
shape.Diamond files are also very useful for shaping your rubber
wheels … and they never wear out like regular files do.
http://www.racecarjewelry.com visit the workshop on the web for some
ideas. We do mold making,Casting /finishing in gold,
silver , bronze and pewter for the Trade.