[Ooop. Mailed instead of posted....]

Parlous wrote:

I need a way to grind silver bullion into basically dust sized
particles. I have manually taken a rasps, files and such and gotten
the desired results by hand. However, this takes forever and is a
lot of time and work. I need a mechanical solution.

It's not perfectly clear whether you're making some kind of workpiece
or if you just want to produce silver dust/grit.

In the latter case, see if you have some kind of low-speed
reciprocating widget or parts to make one lying around. Rig up up a
power filing machine with a simple table and some kind of spring feed
for it. Mount a file of whatever coarseness works and turn it on. Set
it in a wash tub or the like.

No need to complicate things with a lift-off on the back stroke
because silver won't mung the file teeth on a back stroke as steel
does.

Should run unattended for quite a while depending, of course, on the
size & shape of your bullion.

Or maybe one of our used gear guys here will have a ready-made power
filer for you.

If you want really fine silver dust, dissolve the silver in nitric
acid, neutralize any residual acid, then put copper scrap into the
silver nitrate solution. The copper replaces the silver in solution
and the silver precipitates out as very fine powder. Filter, wash and
dry.



--
Mike Spencer Nova Scotia, Canada