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Want to give a finishing touch on zinc plated pipe where plating was not proper
I am working in a factory in india, where we plate threaded pipes with blue passivation. But we are having some problem with the blackish spot on the surface.
We are now using silver paint to give patch works, which is not at all having any match to the remaining plated area. So anyone can suggest me a paint which can be used externally?
plating shop quality inspector - Mumbai, Maharashtra, India
This is obviously not good practice, and I would suggest that you concentrate on improving the plating rather than focus on how to make defective plating pass for acceptable plating if that is the case. But there can be valid reasons, and you are not the only shop to do it. Because your customer must approve the change anyway, the best and safest approach is to let them specify the paint.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey