White rust on galvanised sheet and its effect on paint

I would like to know if there is a white rust formation on galvanised sheet surface and If we paint the surface with etch primer+surfacer+PU-top coat OR with Epoxy primer surfacer+PU Top coat, will paint peel off in future.

Hemant Kamat
Buyer - Belgaum, Karnataka, India
October 16, 2009

Hi, Hemant. Etch primer is a consumer's way of treating a galvanized surface for paint adhesion, but a supplier's way would usually be to phosphate it. That is, if you are selling what you are painting, I wouldn't usually trust an etch primer as good enough to guarantee adhesion.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Ted is available for instant help
or longer-term assistance.

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