How to Make Fiero Fiberglass

Fiberglass makes a good stand-in for plastic.

Pontiac made the Fiero -- a mid-engined sports car -- from 1984 to 1988. Besides the edgy mid-engined sports car layout, the Fiero had other forward-looking features, especially for its day. Namely, it used plastic, rather than fiberglass, body panels. While the plastics used are polymers similar to fiberglass not uncommon to cars, it was a breakthrough. Repairs, replacements and customizations are often rendered in fiberglass. Start by casting a mold using a part identical to the one you want to make, from another Fiero.

Things You'll Need

• Car wax
• Mold release
• Masking tape
• Gelcoat
• Polyester resin
• Fiberglass
• Fiberglass resin brush
• Cutoff wheel
• File
• Sandpaper

Instructions

Make the Mold

1. Dab a light second coat of resin onto the mold area, then stick coarse fiberglass batting to the wet resin so it sticks.

2. Wax the desired part thoroughly. This will not only serve as a mold release, but it will protect the original part from which you're pulling the casting.

3. Mask off any area of the original you're using to make your mold which you do not intend to be part of the mold, using masking or painter's tape.

4. Mix two-part polyester fiberglass resin and paint it onto the area to which you applied gelcoat, using a fiberglass resin brush, and allow the resin to dry.

5. Saturate the fiberglass with resin, carefully working out any air bubbles as you go. Allow to dry, then add a second layer of fiberglass and resin and allow that to dry.

6. Pull your fiberglass off of the original part. Leave the excess in tact.

Repeating the Process Inversely

1. Coat the inside of your mold thoroughly with wax using several coats. Then, use a coat of mold release -- a rub-on or spray-on commercially available release agent for castings.

2. Spray on or brush on a coat of gelcoat.

3. Apply several thin layers of resin, allowing them to dry between coats.

4. Apply layers of fiberglass cloth, smoothing them over your mold like you smooth a sheet when making a bed.

5. Trim the major excess with a cutoff wheel. Switch to a file and then sandpaper to create smooth edges.

Tips & Warnings

• Fiberglass resin gives off strong odors and should be used in a well-ventilated area.

References

• YouTube: How to Make a Mould for Carbon Fiber
• YouTube: How To Fiberglass - Mold Layup
• Ate Up With Motor: Kill Your Darlings: The Birth and Death of the Pontiac Fiero