How to Paint Fiberglass Hull Interiors
- 1). Sand the hull with 220-grit to 320-grit sandpaper after making sure the surface is clean and dry. Wipe away all sanding residue and sand the hull again with 80-grit sandpaper. Wipe away the sanding residue.
- 2). Apply a single coat of a one-part conventional yacht primer and allow to dry.
- 3). Apply two or three coats of a one-part marine topside polyurethane acrylic paint. Use the roll-and-tip method of application for a smooth, sprayed-on appearance. Work with small areas, only 2 square feet at a time. Apply the paint with a roller first for maximum coverage. Before the paint begins to dry, immediately follow up with a 3-inch brush lightly loaded with paint to brush out the "stippled" appearance caused by the roller and to remove the roller lines. Observe the manufacturer's recommended drying times between coats.
- 4). Sand with 220- to 320-grit sandpaper after each coat is dry, . Remove the sanding residue by wiping down the surface with a cloth wetted with mineral spirits or commercially available brushing liquid formulated for use on fiberglass. Do not sand the finish coat.
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