It is difficult to avoid nicks, scrapes, and scratches on a plastic bumper. A runaway shopping cart, parking too close to another car, or pebbles and rocks on the road can easily damage your bumper. More serious cracks and gouges can also occur from minor traffic accidents. Repairing the bumper yourself is a good way to save money and is a fairly easy procedure. Flexible auto fillers work much better for repairing plastic bumpers than harder fillers such as Bondo. The elasticity of flexible auto fillers prevents further cracks from developing once the bumper has been repaired.
Wash the bumper with a mild detergent and warm water. Use a terry cloth or sponge to clean off surface dirt and grime. Rinse the bumper with a garden hose to remove soap residue and then dry with a towel.
Clean the bumper with a plastic cleaner solvent and terry cloth. The solvent will remove ingrained dirt and debris and provide better adhesion for the auto filler.
Purchase a flexible auto filler at an auto parts store. Plastic bumpers have a stamp in the rear of the bumper that identifies that type of material used for the bumper. The stamp contains two or three characters such as PP, PPO, TPE, or PUR. Show these to the counter service person at the auto parts store, who will match match the auto filler with your plastic bumper. The filler kit should also contain a hardener to mix the filler with.
Mix an equal amount of filler and hardener on a clean cardboard surface.
Apply the filler to the bumper. Fill in all nicks, scrapes, and cracks. Shape the filler to the contour of the bumper. Avoid leaving big ridges or lots of excess filler. Allow the filler to dry for the recommended length of time.
Sand the repaired area with 100 to 180 grit sandpaper. Remove ridges and excess filler from the bumper.
Sand the repaired area with 300 to 500 grit sandpaper. Continue sanding with the contour of the bumper until the bumper feels smooth to the touch.
