I was wondering if anyone could point me in the direction of a book
or good resource on striking medallions? Off hand, since I don’t
have the specialized machinery for striking coins, I imagine I’d have
to do it more in the ancient way. The method I read about, that was
used by the romans was to cast an ingot of precious metal. This ingot
was hammered flat, and trimmed to the correct weight. The planchet is
then placed between two dies, which are struck by a hammer. A feature
of this method is that the edge is rough, splayed out often with
cracks running radially.
I would be tempted to try and get hold of a small fly press. These
should be available second hand for about $50-100 and anyone who does
spark erosion or EDM will be able to make your dies from hard steel.
When you have a fly press you will be able to do punching out,
bending and all sorts of other jobs you havent even thought of yet.
I have been able to do this my making a die out of steel, then using
a hydraulic press. We made a series of coins, about the size of US
dime, on a 10 ton press out of copper, then sterling, then 18kt gold.
I would be tempted to try and get hold of a small fly press....
you will be able to do punching out, bending and all sorts of other
jobs you havent even thought of yet.
Could any of you please describe some of the things you do with a
fly press? A friend gave me one; it sat around for a few years
(because I haven’t made up my mind on what die shapes to order from
Dar!). Recently, I tried putting short, vertical pieces of
thick-walled copper and brass tubing in it, and it makes nice, odd
little puffy metal “beads.” It’s fun, but since my time for endless
experimenting is not endless, I’d love a few suggestions (I do not
have a hydraulic press, nor do I want one). TIA
I use my flypress for Blanking, it is set up with two flat hardened
blocks shimmed to be perfectly parallel. From painful experience I
found that it was a good idea to move the bottom block a couple of MM
forward, this stops you pinching the skin on your finger if you hold
the cutters a bit close to the gap! There was a supplier in
Birmingham UK who sold clamps to fit tooling for flypresses, I think
they have gone now, it is getting harder to find specialist tools
here.
Going back to stamping medallions, I came across a guy at one of the
reenactors fairs a few years ago who was stamping coins out of
pewter. to hold the top and bottom dies straight he had a piece of
tube that went over the bottom one (fixed in a wooden stump)and the
top one slid in it. I used the technique to put dimples in stainlesss
steel ball bearings when I made ball closures for belly button rings,
worked a treat!
Since the same methods used by the unscrupulous to produce fakes can
be employed for lawful purposes, you might enjoy “Numismatic
Forgery” by Charles M. Larson
He covers a variety of methods appropriate to the small shop.
Depends what tools you have. Disk cutting, box joint making, swaging
of collet settings, ring sizing, flat sheet decorating, letter
punching, riveting, bending, raising, embossing, hollow half bead
making, solid bead making…
adapting any tooling that came with it would give you something
useful but knowing a decent toolmaker would serve you well. Failing
that you would need a prototype and someone to do spark eroding.
This is not too expensive as it is mostly automated and a workshop
that offers such a service will do most other jobs as well. I hope
that inspires you a little.