How To Fix A Fiberglass Boat Hull

If your fiberglass boat is looking a little worse for wear, you might want to learn how to fix a fiberglass boat hull and make it look like new! This is not a repair for structural damage, just those little cracks and holes which come with age and use. It won't take long to fix and before long you can stop wincing when you look at your boat.

To fix a fiberglass boat hull, you will need:

• Sander
• Sandpaper, 150 and 60 grit
• Scissors
• Paintbrushes
• Epoxy resin and hardener
• Fiberglass cloth or tape - tape would be better for cracks, 7-ounce cloth works well for holes
• Fiberglass rubbing compound
• Car wax
• Gel coat to match the color of your boat
• Masking tape
• Acetone
• Plastic wrap
• Lightweight cardboard

1. Painful as it is, you first have to make the hole bigger. Use the sander and 60 grit sandpaper to enlarge the hole. To fix a fiberglass boat hull, you have to expand the damaged area until you reach a good surface to adhere your patch.
2. Wipe the surface with acetone. Work in a well-ventilated area and keep any flammables away while working with acetone. Immediately put acetone rags outside in a vented container.
3. Cut of piece of light cardboard a couple of inches larger than the hole. Cover the cardboard patch with plastic wrap. Bend the cardboard to the curve of the hull and tape it into place on the inside of the hull with masking tape. This is a crucial step, so make certain that the cardboard fits smooth and tight to the boat.
4. Mix the resin as directed by the manufacturer, working with only as much as you think you can use in 30 minutes. Cut pieces of the cloth or tape to fit your cardboard backing and attach it with resin, working with smooth brush strokes from the center out to avoid bubbles. Continue this process until the patch is brought up to the surface of the boat. Taper ends outward as you work to keep a smooth line.
5. Allow the patch to dry completely. Remove the plastic-covered cardboard from the inside of the hull. Correct any rough spots with the 60 grit sandpaper, then finish with the 150 grit to smooth and finish the patch.
   
6. Mix the gel coat and brush a thin layer over the patch. Carefully cover the gel coat with a large piece of plastic wrap, making sure it is very smooth. Allow the get coat to dry completely.
7. Sand the finished patch by hand with the 150 grit sandpaper. Clean the boat hull with a wet cloth. Buff with the fiberglass rubbing compound and apply a little car wax to protect your repair.