Can you apply epoxy over paint?
Yes, as long as the paint is fully dry and it's a type the epoxy can bond to. What you do next depends on the paint.
Latex or water-based paint: wait at least 24 hours after you finish painting, then apply the epoxy. No polyurethane is needed.
Oil-based paint, including oil-based enamels such as One Shot sign paint: UltraClear Bar & Table Top Epoxy will not bond directly to oil-based paint (or oil-based stain). Oil-based paints also take a very long time to fully dry, and if the paint under the epoxy isn't completely dry, the epoxy may not stick and can peel off months later. If you haven't painted yet, the simplest fix is to switch to a latex or water-based paint. If you have to keep the oil-based paint, seal it first:
- Apply 3 coats of oil-based polyurethane over the paint and let it dry. Our epoxy adheres to oil-based polyurethane without any problem, which is why it's commonly used to seal over finishes the epoxy isn't compatible with.
- Lightly scuff the poly with 220-320 grit sandpaper.
- Wipe it completely clean with a lint-free cloth and denatured alcohol, and make sure it is fully dry with no residue or oils left on the surface.
- Apply your epoxy seal coat and flood coat as normal.
Shellac is another finish our epoxy won't bond to. If the surface has been shellacked, sand it down to bare wood, clean it with acetone or denatured alcohol, and then apply the epoxy as normal.
Whatever paint is on the surface, you still do a seal coat of epoxy like normal before the flood coat; the paint doesn't replace it.
All epoxy has a slight amber hue that is only noticeable when poured over something white, and oil-based polyurethane has the same tint. For white or light painted surfaces, UltraClear Art & Craft Epoxy keeps the best clarity.