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Product to increase adhesion of metal finish (e.g., chrome over chrome)

Anyone have any ideas on how to make metal more receptive to the finish.. electro cleaning does not seem to be enough ; bubbling and peeling occur... Also, is there a product available that would provide good adhesion of surface treatment. I want to avoid cost and mess of stripping for example doing chrome over chrome.

Thanks,

Terry Hasson
- New York, New York USA

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Terry,

Every metallic surface has diffferences to another even when made out of the same metal, more if there are different metals involved. To give you some clues you have to define what you want to adhere on what. Certainly, chromium on chromium can sometimes be done without striping. But again, it will depend on a number of things such as time elapsed between rechromes, roughness, stress and functional and aesthetic requirements, cost, etc.

Guillermo Marrufo
Monterrey, NL, Mexico

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Terry, you don't mention whether you are doing hard chrome or decorative chrome. You imply going from electrocleaning to plating without activation, which is usually wrong, and you seek a product to go between the original layer of metal and the new layer whereas what you probably really need to do is the opposite (get the original surface down to clean active metal).
Please describe the steps in some specific process sequence you are running and let us try to assess with you what may be wrong with the process as opposed to asking us to accept the implication that conventional electroplating doesn't work so some new miracle coating is required. Thanks!

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