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. :-)
