Friday, May 10, 2013

Alternative Pickle for Brass and Nickel Silver

Last year I wrote a post on pickling sterling silver with a mixture of vinegar and salt, a more eco-friendly alternative to pickling with Sparex. I'm still using that method for sterling, but have moved onto something else for brass and nickel silver.

While vinegar and salt worked okay with brass, it often left a hard-to-remove pink film on the surface, which I'd have to remove by sanding. Needless to say, this can take a lot of time.

After some digging, I found a better method, again, using common household supplies: vinegar and hydrogen peroxide, aka Peracetic Acid.

Peracetic Acid is used to disinfect surfaces and even food, such as fruits, veggies, and raw meat. Pardon my hyperbole, but it works miracles on brass and nickel and rivals commercial solutions, such as Sparex.

Here's what I do:  

  • In a glass or plastic bowl or jar, mix two parts distilled white vinegar with one part hydrogen peroxide
  • After soldering, submerge your piece in the mixture until all oxidation is removed. Use tongs.* Give it at least 20 minutes.
  • Occasionally agitate the piece to hasten the pickling process. Brushing your piece with a paint brush while it's submerged can speed things up.
  • Remove your piece using tongs, rinse it off, and voila--your metal is clean!
  • The surface of the brass will often look crystallized. Remedy this by gently polishing the piece with steel wool or buffing with very fine sand paper.
  • Finish as usual.

*Even though Peracetic Acid is used in food cleaners, disinfectants, etc. I recommend using it with caution. Use the mixture in a ventilated space and use tongs when handling your piece.

Here's a before-and-after of the first piece I pickled. I left it in for about 15-20 minutes. The mixture will turn blue. As the solution becomes saturated, it will become an even brighter blue than what you see in the solution below.


Disposal

Unfortunately, the mixture isn't reusable, so I recommend pickling in batches. After some experimentation, I found the solution can be used for several pieces. It tends to work until it's bright blue and cloudy. For disposal, I dilute the mixture with water and run it down the drain, or I let it sit on my back porch until it evaporates.  I'm not clear on the safest method for disposal, so if you know something, please share your thoughts in the comments!

I hope this helps!

Happy Spring,
Angela


Sources
Alternative Metals Tips for Soldering Copper and Brass from Jewelry Making Daily

Bill Sealy's Pickle Formulas