OK, here’s a weird one. I’ve got a client who’s wanting me to help
him work out the manufacturing aspects of making custom coin holders.
(No, unfortunately, buying stock ones won’t work, for a variety of
reasons.) To grab the edges of the coins, I need to figure out how to
make (and then bend) silver “C” channel. I’ve got a full machine
shop, so making tooling isn’t a problem. The problem is that we need
about 8 different widths of channel, from Xmm to X +2mm, by.25mm.
My thought about how to get “C” channel was to take wide fine
siliver bezel strip, and make up something sort of like a mini
rolling mill, except instead of having flat rolls, it has a square
groove turned into the lower roller, with a square (in cross section)
raised ring in the upper roller. In use, the wire gets folded down
into the lower groove by the raised ring on the upper roller. It’d
probably take a pass or two to get it folded down right, and I’m
worried about having to build the mother of all infeed guides to have
a prayer of it tracking straight.
Anybody seen how the commercial outfits do it? I gave some thought to
just using a bonny-doon press as a brake, but the quantities
involved, combined with lining up the strip killed that thought,
unless someone knows a sure-fire way to do it fast and controllably.
The next question is how to take this “C” channel and then bend it
into a circle. I’m thinking of something like a miniature slip
roller, again with the grooved + tongued rollers. Again, a major pain
to machine up from scratch. Anybody got a better idea?
Any help or suggestions would be greatly appreciated.