Powder on Wood

Q. I have just made new kitchen cabinet doors that I want to have coated. I am working with a local powder coating outfit, but so far we’ve had nothing but failures. Mostly the wood comes out with the coating all bubbled up. The oven is set at 375°F, and we preheat for 10 minutes, apply the coating and then bake for 15 minutes. Any help would be greatly welcomed.—L.O.

A. If you are trying to powder coat natural wood (oak, walnut, pine, etc.), you will not be successful. There is too much moisture content, and the coating will always release trapped moisture, resulting in bubbles. So your problem may be that you do not have a suitable board, and if that is the case, you will have a lot of trouble avoiding the bubbles. 

If you are trying to coat medium-density fiberboard (MDF), you have a fighting chance, however. There are suppliers of MDF made specifically for powder coating with the right moisture content. Application on MDF is not a simple process, however. It will require a coater with experience on MDF and the right powder system arrangement. The board has to be prepared correctly. It cannot have rough, exposed edges. It may need a router cut on the back side to relieve trapped gas and moisture. It must be preheated to a precise temperature range and coated at the right temperature. It must be cured in a very controlled fashion, and 375° F is too hot.

It sounds like you did not select a board that is suited for powder coating and your coater is not experienced with powder coating on board. I suggest you consider liquid paint.