Casting pre treatment

Does anyone have any about pre treatment of silver
casting before barrel (tumbler) polishing. I have been filing up
small castings and barrel polishing them. The finish is very
shiny, but there is still a slight amount of roughness from the
filing. I don’t really want to spend a lot of time cleaning up
castings when I feel that the barrel polisher should do that.

Richard W
UK

Email: riich@rw.clara.net

Hi Richard, Before tumbling you can remove lots of parting lines
and scratches by using a Beartex wheel (available from Gesswein)
with your polishing lathe. They come in 4" and 6" diameters and a
couple of different grits. Good luck. J.A.

Hi Richard,

Why not use a cut-down media (and the appropriate solution) in
the tumbler before tumbling with the steel shot? I’ve had good
results from the fine plastic media and deburring solution sold
by Rio Grande. I just wish that I hadn’t followed the
salesperson’s suggestion and bought the plastic media containing
formaldehyde — I think I could deal with slightly less cutting
action in return for not having to wear a respirator and rubber
gloves when working with the stuff.

Hi Mike, I wasn’t aware that there was a plastic media for
deburring. I will try to locate some. I was a little concerned
about using abrasive media in the tumbler as the tumbler is made
from plastic and I didn’t want the inside to become scratched
thereby reducing the quality of the finish when I use the steel
shot for polishing. Richard Whitehouse

UK

Email: riich@rw.clara.net