As we get older, we may consider having "some work done" to remove age spots, blemishes or wrinkles. As boats get older, they need help, too. Gouges get filled in, canvas or teak gets replaced, and hulls and decks go from gel coat to paint and wax. Painting over a fibreglass deck is like cosmetic surgery, offering a long-term solution that prevents the degradation of your boat's finish, or perhaps improves it with non-skid deck coatings. The key to a successful project lies in the steps you take.
Mask the edges of the area you plan to paint with painter's masking tape. Make temporary covers out of plastic trash bags to cover deck hardware, vents and other items on deck that will not be painted. Secure the bags with duct tape.
Wash the area to be painted with liquid dish soap and water. Rinse the area with running water and allow the area to dry completely. Dip a clean cloth in a dewaxing solvent, such as MEK or acetone, and wipe down the area with the solvent to remove any grease or wax adhering to the surface.
Sand the deck with 80-grit sandpaper and an orbital sander to rough up the surface so it will accept paint.
Make spot repairs to damaged fibreglass with epoxy paste. It's thicker than the regular marine epoxy, and epoxy takes longer to set than gel coat or other polyester fillers, but epoxy paste creates a more stable, harder surface. Once the epoxy has cured thoroughly, sand it level with 80-grit sandpaper.
Mix the two-part marine epoxy primer paint according to the paint manufacturer's instructions, in batches small enough to apply quickly with a paint roller. Allow the primer to dry, and sand with 220-grit sandpaper and the orbital sander. Wipe the sanding grit away with a cloth dipped in acetone, and rinse the area with clear water, allowing the surface to dry completely before painting.
Mix the finish coats of marine epoxy paint in small batches, thinned with the paint's solvent. Apply the paint in three thin coats, using a paint roller. After the painting project is complete, mark the area as "off limits" and allow the paint to cure thoroughly. Remove all masking materials, including masking tape and temporary covers.
Apply automotive paste wax to the newly painted area, using a circular, overlapping motion. Allow the wax to dry to a whitish powder, then buff the waxed area with an orbital buffer.
If you're applying a commercial specially formulated non-skid deck paint, follow the specific instructions for mixing the final coats of paint. If you're living aboard during this process, remember that paint fumes "sink." Turn on the ventilators to dissipate the fumes as quickly as possible, and bag your clothes and bedding. Sleep on deck, or completed portions of the deck, if a hotel room isn't a possibility.
A well-ventilated space is a must for every painting job.