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Bright acid tin parts not plating and turning black

September 13, 2009

We own a plating company in California.. We are having trouble with our
bright acid tin... The parts are not plating and turning black.. Can anyone
help me with this...

Krupa PAndya
Owner - Fullerton, California

I do not have my trouble shooting book anymore, but I suspect that your anodes have passivated. I will also hazard a guess that your anode bags have not been changed recently. Next would be it acid content in range? Has your solution gone from clear to milky to a light creme to a dark creme color, if so contact your vendor--Two choices, dump and rebuild or go thru an expensive treatment that a few companies offer.
What is your tramp metal concentrations. Any possibility that you got some nitric acid added instead of sulfuric?

James Watts
- Navarre, Florida
September 15, 2009

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