I just finished making a plywood door for a game cabinet The original
door had been made of particle board, but the 3/8" lip on both ends
had begun to disintegrat over the years.

Since the disadvantage in using plywood is that it tends to warp, is
there a good way to seal it to prevent this before I prime and paint?

I have something called Thompson's WaterSeal, but don't know if I
should use that before I prime with an Enamel Undercoater Primer/
Sealer (by BEHR) I have.

Any recommendations?

Thanks.

Darren Harris
Staten Island, New York.