How to Do Fiberglass Body Work

by Contributor

The most challenging part of doing fiberglass body work yourself is being patient. When working with fiberglass, tedious sanding can last for hours and even days. Being well-prepared and having the proper equipment will add to the ease in which the job is done. The quality of the work will depend on the time and effort you put into it.

Sand and clean the area to be repaired. This sanding should remove all paint and grease and even out the surface. Pull out any large dents. Wipe the area down with acetone or rubbing alcohol.

Mix the filler with the hardener according to the manufacture's instructions on the 10"x10" cardboard piece. Use an acid brush to stir the hardener into the filler. When the color is uniform, the mixture is ready to be used.

Apply the mixture to the area to be repaired. Fill in deep areas and smooth over until as flat and level as possible.

Allow to dry for 24 hours. Test the repair by touching the filler with your fingernail to see if cured properly. It should be hard to the touch and your fingernail should not be able to alter the texture. If tacky, allow more time to cure. Colder temperatures can take longer to cure, so curing in an area where it's at least 70 degrees is ideal.

Sand. Start by using the 60 or 100 grit types, and as the repair gets smoother, use the smaller and smaller grit sizes. Use the spot putty on indentations or blemishes. Allow to cure before continuing to sand.

Paint and dry once the desired texture is achieved in repair.

Tip

  • check In a pinch, curing times can be accelerated by applying heat with a hair dryer. Do not overdo this, as it will make your filler brittle. To smooth your filler, take some warm water and apply small amounts while smoothing with your finger. The smoother it is, the less sanding you will have to do.

Warning

  • close Always mix and sand fiberglass in a well-ventilated area. Always use proper protection to include latex gloves, eye protections and a respirator or dust mask.

Items you will need

About the Author

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