However, for very small cosmetic gelcoat repairs, epoxy can be used, then finished with gelcoat, as long as you do all of the following:
- Measure the epoxy resin and hardener accurately, then mix and apply, as directed.
- Allow the epoxy to cure completely.
- Use a Scotch-Brite™ pad and water to remove any amine blush, then allow to dry completely.
- Prepare the surface properly, following the directions in the TotalBoat Gelcoat Technical Data Sheet.
- After sanding and fairing (use mixed epoxy blended with a little silica thickener and microballoons), wipe clean with acetone.
- Apply the gelcoat over the repair area.
For larger applications, you must clean the surface to remove any amine blush, allow to dry, sand the epoxy smooth, then apply an epoxy tie-coat primer such as TotalBoat 2-Part Epoxy Primer or TotalBoat TotalProtect Epoxy Barrier Coat Primer. Before applying gelcoat, sand to give the gelcoat a surface to bond to, and remove sanding residue.
IMPORTANT: Epoxy fairing compounds such as TotalBoat TotalFair will prevent gelcoat from curing - gelcoat should never be applied directly over TotalFair.