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Paint peels off from AL6061 casting
I have a problem with an aluminium part that we paint without using cromatic coating due to some requirement from the USG contracts. So far no problem after many parts . . . but suddenly 4 parts the paint peels off. Please advice
Natan Cohen
- Israel
February 2, 2011
Hi, Natan.
If anyone has started using a silicone release agent, or silicone anywhere, your pretreatment cycle cannot remove it. It's almost impossible to remove. Please study whether silicone got into the sequence somehow. Good luck.
Regards,
![Ted Mooney, finishing.com](../portraits/ted_mooney_beach.jpg)
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
February 2, 2011
If I understand you correctly, you don't use a chromate conversion coating as it is restricted. Hex chrome is a big NO NO but you have to use a trichrome conversion coating instead of it. You cannot paint Aluminum with no conversion under at all.
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Sara Michaeli
Tel-Aviv-Yafo, Israel
February 22, 2011
If no Chromate is allowed you can use a Wash Primer before you prime and paint.
Mike Nelson- Chattanooga, Tennessee, USA
February 23, 2011
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