cleaning post-pickle scum from tiny hard-to-handle pieces
Hello-- and HELLLLP! I'm getting arthritis from wire-brushing bb-sized granulated balls of silver & bronze. After pickling them, they need to be cleaned and I'm having an increasingly difficult time handling them... Can they be tumbled clean? (Please don't laugh at my ignorance-- I'm new to metalsmithing and just make everything up, and sometimes Googling is futile) I will be everlastingly grateful for any tips on how to clean tiny metal pieces which are too small to handle and wirebrush easily. Thank you, thank you!
Stacy's Answer:
Tiny items can be a challenge! Tumbling will not remove torch residue/firescale.....pickling does that. You may just simply need to leave the granules/balls in the pickle longer - until the silver is silver-colored again. If it's pinkish or black, it needs to soak longer. (fine silver or Argentium silver stays white and does not or rather should not turn black after torching. No pickling necessary. It's also preferable for granulation work because there is no porosity which can distort the tiny round balls and they require no solder)
Bronze and brass often looks pink after the torch crude is removed. To restore it back to it's golden color, soak in a solution of 3 parts white vinegar to 2 parts hydrogen peroxide. The metal will get tiny air bubbles on it and the solution turns blue as it works. This process takes about 15 minutes. Don't think you can skip the pickling, because the torch residue must be removed first! It is VERY IMPORTANT NOT to forget the metal in the "de-pinking" solution as prolonged exposure will damage the metal. A half-hour of less is fine. You can then tumble your granules to shine them up. That being said, the idea of picking those balls out of the shot sound like no fun! A good eye and tweezers would be a must! If your pickle is not cleaning the metal, perhaps it's time to refresh or replace it.
However (yep, there's always one of those), why are you going through all the effort to polish them up before soldering or fusing them on something? I wouldn't bother to polish them - just pickle to remove the torch residue to prepare them for use in your jewelry designs. As you'll be torching them again they'll get "dirty" again. Do the major cleaning and polishing AFTER they've become a piece of jewelry. (yes, you can put silver in the vinegar/peroxide solution if it has bronze or brass on it to yellow up the brass.) Then tumble or buff to polish the metal to a high shine.
If you really need to scrub/brush the metal BB's, you could staple some fine mesh screening to a wood frame to create a contained flat area that allows you to spread the balls out, but keeps them from escaping. I'm thinking at least 6 inches x 6 inches with one inch framing and the screening needs to be tight! Simply place the sieve on a flat surface, perhaps with toweling under it, dump in the granules and use a large soft brass brush to scrub them en-masse without having to hold them individually. Pick up and rinse the whole business! Now they're ready for soldering. Or perhaps all they need is to simply be rolled in damp toweling to remove any leftover residue from the pickle pot?
I've given you a bunch of choices here because I cannot see what your metal pieces look like or talk to you to better help me ID the problem. Whether it's the pickle solution, the residue from pickling, the pink brass/bronze after it's been cleaned, etc., I hope that one of the above or a combo of the solutions will simplify the finishing process for you and save you from the arthritis-enhancing ones!
