What are the plastic beads with the HF tumbler for?

by Sarah
(Ithaca, NY)

I am tumbling sterling silver in my HF tumbler for the first time ever, and am having trouble with the pieces getting the black/hematite look. I will try some of the remedies discussed here, but am wondering something. The tumbler came with a large quantity (at least twice the volume of the stainless shot) of yellow plastic beads. Should I remove the plastic beads from my tumbling process? Could they possibly contain the contaminant that turned my silver dark? (BTW, the pieces I'm tumbling are numerous and small, so I'm hoping against hope that I won't have to hand-polish all of them.) Thanks.

Stacy's Answer:

Hmmm...well, what did the plastic pellets say on them? Are they impregnated with some sort of chemical? I've only seen/used the small white ones that resemble rice. (BTW...rice is NOT a good choice for tumbling media when tumbling items such as intricate wire pieces, etc. The stuff wedges everywhere and the powder turns to rice glue when wet) There's really no point in using plastic media along with the metal shot.

Also Sarah, I don't think that Harbor Freight supplies stainless steel shot with its tumblers. I know that they DO NOT carry it in their stores in my area or online. They do have some steel tumbling media along with different cutting agents used mostly for rock tumbling. As steel shot rusts when combined with water it's considered a dry media and should never be used in lieu of stainless steel shot. If you purchased everything as a kit from a third party, I would contact them and ask what exactly they provided in the tumbling kit and what its purpose is and how/why/when to use it.

The HF tumbler barrels are well known for their often poor quality rubber which sometimes leaches a chemical that can give pieces an off-color. This does eventually go away. Once the rubber becomes "seasoned," the little machines seem to do a fine job. Using a clean barrel, shot, etc. should produce bright silver pieces, assuming the pieces were bright finish to begin with. If they were oxidized using a patina, then they come out shiny and dark! Buffing by hand removes the excess oxidation.

You can remove heavy tarnish with a commercial product like Tarnex, rinse and wash thoroughly, and then tumble to restore a shiny polish to them. I would rather do that than have to polish all those small bits by hand. :-)

Comments for What are the plastic beads with the HF tumbler for?

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Nov 13, 2011
plastic beads
by: Sarah

The tumbler, stainless steel shot, and plastic beads (little plastic balls) came as a set from a seller on Ebay. The amount of shot provided completely filled a 2" x 3" zip bag (and looks exactly like the blend that Rio Grande sells for $18/lb.). Is this enough shot for tumbling some small pieces, or should I buy another pound of the mixed shot? I separated the plastic beads from the stainless shot and cleaned the shot with flat Coke and then again with water and Dawn. They are looking much cleaner. Then I washed the tumbler really well *once again* with Dawn (rubbed hard with sponge, but not enough to mar the surface of the rubber. Next I'm going to try cleaning all my beads with Tarnex and then tumbling them again. I've got my fingers crossed...

Aug 05, 2015
Plastic Balls
by: Anonymous

I have used half stainless steel shot and half yellow plastic balls to tumble my jewelry (mostly sterling) since I got the tumbler. It has always worked fine and the stones or crystals are not damaged.

Oct 11, 2015
Another chamber inside HF tumbler
by: Anonymous

I bought a tumbler two different times from Harbor Freight and both turned my silver a nice gun metal gray. So I found a cashew butter jar (plastic) and now tumble inside it inside the rubber barrel. I got 2 large "0" rings from Ace hardware to fit around the plastic jar to act as wheels so ir doesn't just slip and slide inside the rubber barrel. Don't really know if that works maybe just vibrations are doing the trick. But things do come out pretty.

Oct 13, 2015
Temp Fix to a Bad Tumbler Barrel
by: Stacy

I don't think the plastic has anything to do with the quality of the finished product, but keeping everything away from the bad rubber does. As many of the rubber barrels seems to have faulty rubber that leach gooey crud coating the jewelry and shot, your solution sounds great in a pinch - or perhaps longer!

Very ingenious and I would not have thought of that! Thanks!

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