A vehicle with a damaged bumper doesn't necessarily need to be taken to an automotive repair shop. If the bumper has minor cosmetic damage, such as small scuffs or holes, a car owner can usually fix the bumper at home. However, for heavy damage, such as a crumpled bumper or a bumper that has been broken into separate pieces, installation of a replacement bumper is probably in order.
Prepare the bumper for repairs by scrubbing it with a grey scuff pad and a wax/grease cleaner. Follow up with a plastic prep cleaner.
Sand the front of the bumper with 80-grit sandpaper, and the back of the damage with 24-grit sandpaper, extending three inches around the damage. Blow all of the sanding dust off with an air compressor.
Apply an adhesion promoter to the back of the damage with a paintbrush and let it dry for 10 minutes.
Cut a piece of wire mesh with wire cutters. Make sure that it is large enough to extend one inch around the edges of the damage, then spread a thick layer of bonding adhesive over the adhesion promoter with a putty knife. Push the wire mesh piece into the bonding adhesive and cover it with another layer of adhesive. Let the adhesive dry completely.
Sand a hollow over the front of the damage with 24-grit sandpaper. Spread body filler into the hollow with a putty knife and press the filler to remove any air bubbles. Smooth and let dry.
Sand the front filled area with 80-grit sandpaper, and then again with 180-grit sandpaper.
Seal the bumper cover with a flexible bumper sealer, spraying evenly.
Prime the bumper for paint with a coat of flexible bumper primer surfacer.
Apply a bumper colour coat and then wet sand the bumper with 320-grit sandpaper once the paint has dried. Rinse well and let the bumper dry once again. Apply four more layers of paint, sanding and rinsing between each coat. Apply another coat, wet sanding with 400-grit sandpaper this time and rinsing afterward. Apply one final coat of paint and let it dry for 12 hours.