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Tumbler Contamination cleanup


I have two identical HarborFreight tumblers [3 LB. Rotary Rock
Tumbler]. One is working OK, but second got contaminated somehow and
is staining my silver jewelry gold, or black when dipped in Liver of

Any tips/ideas how to clean it.


sounds llike you have some sodium hydroxide ad potassium
permanganate problem…the characteristic is that it turns
silver, brass and aluminum gold…

so you need to neutralize your tumblers with soda crystals / baking
soda./bicarbonate of soda and water first, then scrub them out with
something akin to a green 3m polyweb pad…you don’t want to remove
plastic as with steel or bronze wool, but you do want to remove
sludge film left by the 4 pack of “chemicals” that harbor freight
sells to go with the tumblers…and buy extra barrels. use one for
each type of chemical they give you or better yet, get your tumbling
and polishing media from a jewelers supply…as the harbor freight
junk contains Na thiosulfate that can ruin many pieces of jewelry,
and stones. There are a lot of 4 step tumbling method kits on the
market, lortone, gemex, etc. try Contenti, Rosenthal’s Jewelry
Supply, FDJ, Lortone, Romanoff, Livasasys, Thunderbird supply or any
number of reputable sellers of media for both extra barrels and the
stuff to go in them…Mark each barrel with a paint marker ( masking
tape and a sharpie won’t hold up like an enamel paint product) so
you know what each is DEDICATED To…that should solve your
problem…some people pay money to have their silver or brass come
out hamilton gold coloured though so depending on the finishes you
desire you may want to keep that barrel for a while. Eventually it
will stop working evenly, then at all though so recreating what you
did is as simple as buying a bottle of Jax metal finish in
gold…Personally, plating is how I choose to recolour metal if
absolutely necessary, but some people like the quick coating of a Jax
type solution.


Try running it for a couple of hours with just some shot and
barreling soap solution in it and then repeat with fresh soap


but second got contaminated somehow and is staining my silver
jewelry gold, or black when dipped in Liver of Sulphur. 

Isn’t that what Liver of Sulphur is supposed to do? : )

I have heard of running your tumbler with stainless steel shot and
flat coke to clean the barrel and shot. Haven’t done it myself.

Hard to Find Tools for Metal Clay

Thank you for all the tips and ideas. Both coke and soda did work.
Contamination was caused by well water. I use bottled water now and
problem is gone.