Fiberglass hoods are a common sight in custom automobiles. Made to spec, these hoods can either reproduce original, hard-to-find parts or can be used to create a unique look. From classic autos to hot-rods, the smooth painted finish that's possible on a fiberglass hood requires that that you follow a specific process. Best results take time, but the look of a well-painted fiberglass hood is difficult to duplicate using any other material.
Sand the surface of the hood with 150 grit sandpaper using a dual action sander. Run the sander over the surface of the hood in small circles. Using the sander removes any coatings left for the hood molding process and textures the hood in preparation for the primer paint.
Repair any low spots in the fiberglass to create a smooth even surface for painting by filling the low spots with fiber glass filler. Mix the filler with about three percent cream hardener. The hardener typically comes with the filler. Place the filler into the low spots using a putty knife, and scrape them smooth, removing any excess and leveling the low spot with the surrounding hood surface. Allow the filler to dry completely for 30 minutes to an hour.
Prime the hood with a layer of sandable polyester primer. Brush the primer onto the hood using three or four coats until a solid layer is present. Spray a coat of black lacquer paint over the primer. Wait overnight for the primer coat to dry.
Wet-sand the primer coat with 220 grit sandpaper placed on a rigid sanding block. Sand the paint until a smooth surface is created without any flaws from the patching process seen.
Place another coat of black paint onto the food, and allow it to dry overnight.
Wet-sand the new paint coat using 400 grit sandpaper. Use a mild amount of pressure to create a completely smooth surface.
Remove any grease on the hood left by your hands during the sanding process using a grease remover.
Apply a base coat of paint to the hood. Apply the coat using three thin layers of paint, building up to a solid coat a layer at a time, allowing the paint to dry two hours between layers.
Apply a layer of clear coat paint to the hood to lock in the base coat and prevent damage. Allow the clear-coat to cure completely overnight.
Wet-sand the clear coat layer with 2000 grit sandpaper. Sand away any imperfections in the finish until you have a mirror clear shine from the paint. Allow the solvents to evaporate from the paint to finish the curing process for about three hours.
Polish the clear-coat with a car polish to a high glossy shine. Apply the polish using a clean cotton rag. Wait for the polish to grow slightly hazy. Then buff the polish to your desired finish.
