Ask the Expert Question-and-Answer Archive

by Ron Joseph

April, 2007

Painting Over Powder Coated Metal

Q: I purchased a white powder coated metal courier box and I am trying to paint a design over some of it. We are using an enamel paint and it's peeling off. We only painted it 2 days ago and it's been cold since then. Did we pick the wrong type of paint to use over powder coated metal or do we just need to wait longer for it to harden/dry?

We didn't do anything to the powder coated surface except wipe it off, it was brand new. We painted the top of the courier box and some stripes around the sides and back with an enamel paint for metal. I'm hoping that all we need to do now is just leave it along and wait until it's warmer so it hardens. Thanks for any help you can provide.

A: Unfortunately, powder coatings are very hard and do not easily allowed other coatings to adhere. A better method for recoating the powder is to lightly sand it with 180 grit sand paper, solvent wipe and then follow with a two-component epoxy primer followed by the enamel of your choice. If that is too much work, then at the very least, the powder should be abraded followed by solvent wiping to remove all the loose dust. Apply the topcoat and hope for the best.

Regards,

Ron Joseph