Fill it before you use gelcoat filler

Gelcoat filler is great for filling surface scratches, but it’s so runny and thin that you’ll struggle to fill a deep gouge or hole. It’s best to fill them with thickened epoxy as the ‘bulk’ before you then finish off with a thin gelcoat filler layer. Tip – put tape over the top to keep the filler in and keep the surface smooth.