How to Harden a Fiberglass Bumper

A fiberglass bumper protects a car's engine during minor accidents.

Fiberglass is the material used to create parts of a car such as bumpers. When making the bumpers, you can begin with making a mold of the shape you want by mixing fiber glass and resin. There are various ways of strengthening a fiberglass bumper.

Things You'll Need

• Mold
• Primer
• Wax
• Aerosol coat gel
• Sandpaper
• Polyester resin
• Brush

Instructions

1. Create the mold on which the fiberglass will be molded according to the shape you want.

2. Apply a primer to the mold’s surface. Scrub the prime using a sandpaper. Polish the surface to have a clean finish and then wait 24 to 48 hours.

3. Apply wax on the bumper using a mold making wax. Leave the wax to dry and then wipe away any excess wax on the surface using a piece of cloth. Repeat this process two to three times.

4. Apply aerosol coat gel on the surface of the mold. Apply several coats and wait until it gets sticky. As it dries, mix the polyester resin.

5. Apply the resin coating to the bumper surface using a brush. Lay the fiberglass sheets on the sticky surface while the resin is still wet. Smooth the surface with a brush to remove any air holes.

6. Add extra layers of fiberglass by applying extra resin coatings. Allow it to dry and harden. Remove the finished bumper from the mold gently.

References

• JPSSPFX: Mold Making
• Fibreglass: Moulding Fibreglass