Join Date: Jul 2012
Location: Burton Michigan
I can tell you from personal experience that your problem is the paint, not the poly. The poly will only cure as hard as the substrate. Black latex paints ,or any acrylic recipe for that matter, has so much universal tint pigments in it that it will never cure to 100%. The best thing you can do is get an acrylic paint like you just bought and have it mixed to dark blue. Use that as your base color coat. Let it cure for 48 hours, and then tint your poly black with some trans tint dye. Use several coats of the tinted clear coat until you rich a rich black color. Let each coat cure for 12 hours.
Sounds silly but there is a huge difference in the amount of pigments used to make navy blue as opposed to black. Blue is mixed from a lighter tint base that has less pigments to begin with, black is mixed from a dark tint base.....
After years of fighting with the exact issue your having, and thus figuring out the method I just described. I have since switched to a Sherwin Williams system called Kem-Aqua Plus. It is a waterbased laquer that is incredibly durable, no clear coat necessary. It also comes in black.
**also** A good indicator that you have applied the poly to thick is that it will crackle. If its too thick you will see webbing or broken glass effect all over it. If you dont see anything like this in your clear, you didnt apply it too thick.
Last edited by Drakmare; 07-17-2012 at 08:34 PM.
Reason: added info