Can You Patch Auto Floor Pans With Fiberglass?by Brenda Priddy
Floor pans are the base, metal layer of a vehicle's floor that everything else rests on. Usually, the pans do not rust or need repairs. However, sometimes it is necessary to repair holes in the bottom of the floor pan. This is most common for older cars. One of the best ways to patch the holes is with fiberglass sheeting. This patches the holes and adds a strong layer over the floor pan which can actually improve the strength of the entire floor pan.
Unbolt all of the seats and remove them from the vehicle. Pull up the carpet and any padding to expose the floor pan. Use a utility knife, if necessary, to break the adhesion bond between the carpet and floor pan.
Remove any rust from the bottom of the floor pan using a power sander and 40-grit sandpaper. Wear a dust mask and eye protection to protect your eyes and lungs. Wipe away rust residue with a damp cloth.
Spray the floor pan with rust-inhibiting spray paint. Allow the paint to dry for two hours.
Cut a sheet of fiberglass 2 inches larger on all sides than the holes in the floor pan. Cut two sheets for each hole.
Brush some fiberglass resin around the edges of the holes. Place a fiberglass sheet over the resin. Apply a second layer of resin over the top of the fiberglass sheet. Allow the resin to harden for about 12 hours.
Apply a second layer of resin over the patches. Press the second sheet of fiberglass over the first sheet. Apply another layer of resin over the top of the sheets. Allow the fiberglass to dry for 24 hours before replacing the carpet.