Copper coming out dark brown?

by Rich

Hey I just got a HF tumbler for Christmas. A much needed item that should save me hours of polishing... I use stainless shot, and tried Dawn dish washing soap, later switching to AJAX. Yet it seems every time I run the tumbler, no matter the amount of soap I use they always turn brown within 15 minutes.

Should I switch to a burnishing compound? like the Sunsheen that Rio Grande sells? or is it something else ruining all of my pieces?

Stacy's Answer:

Hi Rich,

While the HF tumblers seem to run well, there have been many issues with the quality of rubber used in their barrels. If your jewelry items continue to come out of the tumbler with a dark stain on them and no patina had been added to the metal prior to going into the tumbler - it sounds like you've got one of those bad rubber barrels.

There are lots of threads here on just that subject. Sometimes the rubber stops leaching after a period of time, "seasoning" I like to call it. But there are no guarantees. Switching out the barrel may do the trick, or you may need to go with a different manufacturer like Lortone or Thumbler Tumblers. Have yet to hear of a problem of bad rubber with those.

The Rio products you mentioned are great for bright-finish metals, but not for items with a patina like liver-of-sulfur added. The LOS patina get splotchy or goes away all together.

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