How to Repair PVC With Fiberglass

Fiberglass is commonly used for repairs or reinforcement on materials such as plastics, wood, metal, and even plastic foam. Fiberglass will bond to almost any surface, like PVC, as long as the surface is properly prepared and scuffed.

To repair PVC with fiberglass, you will prepare the damaged area, apply three layers of resin-saturated fiberglass mat, let the fiberglass cure, and sand the patch smooth. You can find fiberglass repair kits with the mat, resin, and catalyst or hardener online or at a local auto parts supply store.

Put on safety glasses and grind the rough edges of the damaged PVC smooth using a die grinder. If there is a deep fracture, grind the damaged PVC out of the middle of the crack and gradually taper the edges. Lightly grind 6 inches all the way around the damage, being careful not to go deep into the PVC.

Wipe the damaged area clean using a rag and acetone.

Use a razor knife to cut three layers of fiberglass mat that completely covers the damage. Make each layer 1/4 inch smaller than the last so the edges of the repair are tapered and not ledges.

Follow the product instructions for the amounts of fiberglass resin and catalyst to use and mix in a small bucket. Use a wooden stir stick to thoroughly mix the catalyst with thee resin.

Wet out the surface of the repair with the resin using a 4-inch felt roller. Apply the smallest layer of mat first, with the damage directly in the center of the mat.

Saturate the mat with the felt roller and roll out any air bubbles using an air roller. Apply the next two layers following the same process and let the fiberglass cure until it's hard and cool to the touch.

Sand the fiberglass patch with 100-grit sandpaper to remove any burs or sharp hairs of fiberglass.