I am looking into getting a tumbler as I spend too much time
sanding and hand polishing components that I get back from casting.
Is there a good "shape" for me to start out with? What is the
difference anyway between a pin shot and ball cone, for example?
Molly, I hand file and sand up to 600 grit before using a tumbler.
For round, smooth beads, I use green plastic fine grit pyramid media
in a deburring compound and distilled water, first to achieve a
satin finish, followed by mixed stainless steel shot in a burnishing
compound and distilled water (4 hours each). A tumbler is
indispensable for finishing pieces with soldered links and fine
The gray porcelain media is supposed to burnish after 12 hours of
break-in time, but I found the break-in period to be more like
80-plus hours. Before then, the porcelain media gave me a satin
finish. Rio Grande suggests a 12-14 hour break-in period, but the
better advice to follow is Judy Hoch in her book on tumbling, run
the media for 5 days, day and night before using with jewelry. I
also tried rouge in walnut shell for a dry tumble media. After
hours and hours (10-plus), I achieved a satin finish with the shells
but massive amounts of rouge entered the beads and I spent more
hours using an ultrasonic cleaner to remove the rouge. Also, I tried
carbon steel shot purchased from a gun shop. It works, but cleanup
of the carbon sludge (which gets on everything) is very time
consuming to remove, not to mention the rust that sets in
immediately. If you don’t want to invest in the somewhat expensive
stainless steel media (which lasts forever), then I suggest using
porcelain as a better burnishing alternative to carbon steel.
I use an inexpensive Lortone round barrel tumbler, nothing fancy but
it works fine. Almost no silver is removed in burnishing and, in
spite of the weight of the steel shot, the metals, including jump
rings and other fine detail are not distorted in tumbling. The
steel media seems to slide around rather than crash against the
piece. Some of the other types of tumblers may be more aggressive.
I remove the straight pins from the mixed steel media when tumbling
annealed copper or round silver beads because the pins seem to poke
occasional pits in the surface. If the piece has fine detail that
only the pins can reach, I run the piece through a second 4 hours.
The Rio Grande catalog includes a chart on Workpiece Identification
and Media Selection, which I found helpful. Also, check the Orchid
archives for more on tumbling. Nancy www.psi-design.com