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Aluminum Surface Preparation Before Top Coating

What happened to the Dupont Two step process to prep Aluminum before priming with zinc chromate ? What products are available now to do this job?

Thank You,

Mark S. Joiner
- Kingston, Tennessee, USA
2002

Alodine, available under other commercial names as well, aka chromate, aka conversion coat, aka MIL-C-5541, is the most effective pre-paint treatment for zinc primer. It's a safe, water soluble mix you can do at home. Just read the directions.

Hope this helps, Greybeard

Lynn M. Perry, Sr.
retired - Plano, Texas
2003

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I beg to differ. Chromates contain toxic, carcinogenic, hexavalent chromium and are not safe to use at home.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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2003

Mr. Perry's description of a chromating solution could not be more incorrect. There is nothing safe about a chromate conversion coating solution, which typically contains chromic acid and ferricyanide. This is not a chemical solution to be trifled with. I would strongly recommend leaving the application of a chromate to people who are experts in the field.

George Gorecki
- Naperville, Illinois
2003

Sorry! Finishing.com is temporarily Read-Only.
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We're working hard to make sure we find it the best new home.

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