What are the Causes and How do I Fix Fisheyes in Epoxy Coatings?

Fisheyes in a solvent-free epoxy coating have a number of causes. Here's how you can fix them.

 1. Surface contamination - Uncured stain, uncured sealer, Pledge® or other silicone-type polish.

Solution: Allow the stain/sealer to cure completely and/or remove the pledge or polish as best as possible before proceeding. This may take a few days to weeks depending on the product used. Lightly sand the existing epoxy with 120-150 grit. Care should be taken not to cut through the stain. Apply another seal coat of epoxy using an 1/8" nap foam roller, working to fill in the craters. Allow the epoxy to cure hard, sand entire application flat, and re-coat to finish.

2. Coating too thin

Solution: This is a common problem observed when pouring less than the recommended depth on the MirrorCoat® flood coat. Allow the existing epoxy to cure hard and block sand flat using 120-150 grit until leveled. If the cratering is minimal, you can use a squeegee to fill in those areas with epoxy and then sand flat. Proceed with the flood coat at 4 ounces per square feet. 

3. Surface too smooth

Solution: Fine sanding is typically the culprit for a smooth surface. This can be avoided by sanding with 120-150 grit. Allow the existing epoxy to cure hard and block sand flat using 120-150 grit until leveled. If the cratering is minimal, you can use a squeegee to fill in those areas with epoxy and then sand flat. Proceed by re-coating with epoxy.