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Posted: Wed Jul 18, 2007 1:02 am
by Chuck(G)
Just some small items like crooks and braces? Silver plating?

I use a 240 grit interleaf flap wheel, followed by a tripoli buff for small things like that. I don't think I'd try it for large parts, though--too much work.

There are electrolytic processes for de-plating. Check with a plating shop for details--this isn't something you want to do yourself.

Remember that no matter what you use, the end product will be thinner than it was with plating intact. This can affect things such as fit.

Posted: Wed Jul 18, 2007 6:32 am
by Daniel C. Oberloh
Stripping silver chemically is done in a cold immersion solution, comprised of a chemical blend of sulfuric acid, nitric acid and potassium-nitrate. Very nasty stuff to work with.


Daniel C. Oberloh
Oberloh Woodwind and Brass Works
www.oberloh.com

Posted: Wed Jul 18, 2007 12:53 pm
by Chuck(G)
I agree with what Joe and Dan said (Dan is the resident expert in electroplating)--and I'll add that since you didn't specify the plating type, there are some plating-specific answers.

If the plating's nickel, it can be stripped by the pros, but generally that's only done to prepare for a new coat--of nickel.

Gold plating can be buffed off--it's thin and soft enough that it's hard to keep it from wearing off on its own.

If you've got an old bugle from some Drum C*rps sale that's plated in chromium, that's another job for the pros, but it can be done.

Posted: Wed Jul 18, 2007 3:24 pm
by Daniel C. Oberloh
The chemical removal of nickel plate is actually quite simple and very effective. I do it in house. The stripping bath oxidizes the nickel and has little impact on the brass or nickel-silver sub-straight. It only has a small amount of sulfuric acid that is only an activator for the compounds used in the bath. I will only chemically strip silver when it is badly etched, and the plating is peeling from a failed bond. Removing loose heavy plate by buffing it off can cause problems just as bad as chem-stripping, it just depends on the circumstances involved as to which way is the best rout. In most cases, it is best to sand and polish as needed and then re-silver plate the instrument or part there of.

I will add that some gold plate is not over silver but nickel plate (modern Conn Hellberg mpcs). I will polish off the remaining gold and remove the nickel plate in the nickel strip bath. Chrome plate is removed in a hydrochloric acid stripping bath.

Joe, do you not have any local plate shops to remove your chrome? I will on occasion use my local guys if the project is time sensitive but tend to have slide tubas sent to Anderson for chrome strip (they probably send it out to the same shop you are talking about). I will then repair and polish the tubes and send them back for nickel. I really only do it on the Olds "fluted' tubes as they are not easy to or are impossible replace. Most everything else is faster and cheaper to replace as you noted.


Daniel C."after recovering from morning traction and ice, felt like being Mr. Know it all" Oberloh

Posted: Wed Jul 18, 2007 8:45 pm
by LoyalTubist
This might be off topic, but don't try to remove the silver plating on your mouthpiece! The raw metal can cause blood poisoning through your lips. I know this from the experience I had as a teenager. This has been mentioned in this forum before.

Posted: Thu Jul 19, 2007 1:11 pm
by Lee Stofer
To the original poster, Jim, feel free to give me a call and discuss what you are actually trying to accomplish. If you need help, I'm just under an hour away.