Are your car’s body panels made entirely out of metal? Chances are they are not. Most car manufacturers use fiberglass and/or plastic to make various body panels and trim in order to reduce cost and weight. Unfortunately, while fiberglass is lightweight and looks good, it can crack, break, and shatter due to an impact or even just the passage of time.
Luckily, damage to fiberglass can be repaired fairly easily. Remember, however, to always wear gloves when working with fiberglass. Long sleeves and a mask are also a good idea when sanding fiberglass, as it contains tiny glass particles that are hazardous to inhale and can cause irritation to your skin.

Prepare the Area to Be Repaired

Before a fiberglass panel can be patched or repaired, you will first need to sand the surface of the area you will be applying the patch to. Remove all paint and sand until the surface is smooth to the touch. Be sure to wipe down the area afterward. If there is any wax, oil, or other residue underneath your fiberglass patch, it won’t adhere well and will have to be redone.

Prepare the Fiberglass Patch

Fiberglass is repaired by applying new sheets of fiberglass to the surface of the damage, and then sanding until the area is smooth and in line with the rest of the panel. To do this, we use fiberglass mat or fiberglass cloth dipped in resin.

  • Cut layers of fiberglass mat or cloth. The material is thin, so you will apply multiple layers until you achieve the thickness you want. The top layer should cover the entire area you want to patch, while the bottom layers will be smaller. Cut the top layer to the correct size first, therefore, and then cut each additional layer a little smaller. The smallest (bottom) layers will be applied first.
  • Prepare the resin. Be sure to put on gloves first! Then mix the resin and hardener in a bucket. It is best to buy cheap brushes, buckets, and other supplies and plan on throwing them away when the repair is done, rather than attempting to clean the resin out of everything afterward.

Apply the Patch

The patch will simply be made up of layers of fiberglass mat or cloth dipped in the resin. To start, spread a thin layer of resin over the entire area to be patched. Then — wearing gloves, of course — dip the smallest piece of fiberglass mat or cloth in the resin, being sure that it becomes fully saturated. Place the layer on the area to be patched, and either press it down with a roller or use a brush to push the air bubbles out of the cloth or mat. Repeat with gradually larger pieces of fiberglass cloth until the area is completely covered, and then roll over the entire thing one more time.

Sand the Fiberglass Smooth

Once the fiberglass has cured completely, it will feel cool and hard to the touch. Only then can you begin sanding. Using fine-grit sandpaper, sand away any excess bulk, until the surface is smooth and the patch follows the lines of the rest of the panel.

Finishing Touches

Once the fiberglass is cured and sanded, you may paint the area to match the rest of the panel. Like any other car paint repair, you will need to use primer, colored paint, and clear coat to achieve a finish that will match the rest of the car.
ColorMate Auto Appearance Specialists provides same day quality repair services including car paint and bumper repair, headlight restoration, rim repair, paint perfecting and car interior repairs in Miami-Dade, Broward, and West Palm Beach County. Schedule an appointment for a free estimate on quality car interior and cosmetic repairs.