How to Build a Fiberglass Body

Recreational hobby vehicles made with fiberglass, like boats, go-karts and cars, can be simple to make and very durable. An airtight fiberglass shell helps protect the vehicle from the elements. There can be added construction details, like building a chassis for a car, but building the fiberglass body is similar for any vehicle. The body is originally constructed from substances like plywood and urethane foam and then covered with multiple sheets of laminated fiberglass

Things You'll Need

• Plywood 2-by-2 inch lumber Urethane foam Wood screws Screwdriver or drill Staple gun and staples Epoxy cement Solvent-based cement Razor knife Sanding block Gel coat laminate Polyester fiberglass sheets Particle respirator Polyester laminating resin Bristled paintbrush Saw

Instructions

1. Draw, design and plan every detail of your vehicle body, be it a car or boat. Determine its exact shape and size, along with all the needed pieces and panels and the exact order they must be assembled in.

2. Cut plywood sheets that will form the interior body and assemble them using nuts, bolts, brackets, screws and/or epoxy glue. A car's body should include four corners bordering the front end, hood, seating compartments, trunk and rear end. A boat needs stringer boards along the inner frame to support the outer frame.

3. Assemble the outer body panel pieces along the inner frame. Anything with a flat outer shape, especially boats, can use plywood for the outside. Otherwise, use urethane foam cut into your designed shapes with a razor knife and sander. Paste the foam panels together with solvent cement.

4. Coat the vehicle body with laminate gel coat at room temperature. Lay a sheet of fiberglass cloth over the coated body and coat the sheet with laminating resin using a bristled paintbrush.

5. Apply at least three or four fiberglass sheets on one another, coating each with resin, including the last. Wait for the final resin coat to dry.

Tips & Warnings

• The fiberglass shell you make must be airtight around the vehicle body. This is especially true of boats to prevent water from leaking to the inside. A car's body must be assembled at riding height. This way, you know how much weight the body can sustain when suspended on its wheels and axles. Use a particle respirator when using a sander, especially on the foam