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Powdercoat outcasting

I have metal stall fronts that have been galvanized. My powdercoater has informed me that the powdercoat finish is outcasting. We tried to have the galvanize sandblasted, and they were unable to remove all of the galvanize. What type of galvanize would cause this problem, and how do I get it removed?

Jacquie Kindred
farm - Martins Creek, Pennsylvania, USA
2004

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I think the word you are looking for is actually 'outgassing'. It means that as the part is baked, air/gas/water vapor that are in the small porosities of the finish expand and blow holes in the finish, something like what you see when you make pancakes. However, I'm not sure that that is really the problem you and your powdercoater are having. It sounds more like you need a powder coater who can chemically strip the rest of the galvanized finish and apply a proper precoat, or apply a precoat that is compatible with both the exposed steel and the remaining galvanized finish.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004