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Can we do acid copper plating after cyanide brass

Okay, we are setting up an acid copper plating tank to use for restoration of pot metal and other difficult pitted parts. My question is this, we have a brass-cyanide tank now that we use, and we would like to use this as the strike plating prior to the acid copper, I have heard from some companies that this will work well, and from others that it will not work at all.....HELP?

Bob Belcher
Restorations - Oklahoma City, Oklahoma
2004

It's always a problem when you already have heard opposing opinions, because nothing we can do here can make either of those opinions go away and ease your mind. The moving finger having writ, and all, as Omar Khayyam observed :-)

My bet, not my promise, is that it will work fine if the parts enter the tank "hot" (connected to the cathode) and not so reliably without the hot entry.

Thorough rinsing is necessary for safety because you'll otherwise be dragging cyanide into an acid tank, which is an extreme hazard.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

I think it will work if you plate enough brass to overcome the diffusion into the die cast. Also, since you would prefer that you plate as high a copper alloy form the brass as possible, operate at a higher temperature and if possible lower free cyanide than normal. also refrain from ammonia ⇦this on eBay or Amazon [affil links] additions when you are plating as an undercoat.

Gene Packman
process supplier - Great Neck, New York
2004