How to Prep a Urethane Bumper

Urethane bumper covers streamline the look of a vehicle. Since urethane is not a metal, extra prep work is required for paint to stick to the cover. Without proper prep work, the paint will flake off the bumper cover shortly after attaching it to the vehicle. During the molding process, small holes and nicks form on the outer surface of the urethane. Proper prep work also removes small imperfections from the surface of the bumper cover.

Instructions

1

Hand sand the exposed side of the urethane bumper with 400-grit sandpaper. Wipe sanding dust from the surface of the bumper with a damp rag when the bumper is smooth and uniform with a dull finish.

2

Mix body filler with the amount of hardener specified on the back of the body filler can on a piece of cardboard with a plastic squeegee.

3

Apply a thin layer of mixed body filler over rough areas of the urethane bumper. Allow the body filler to harden to the touch.

4

Attach a 200-grit sanding disc to an orbital sander. Sand the body filler smooth with the surface of the bumper with the orbital sander.

5

Hand sand the entire bumper with 400-grit sandpaper to smooth out any sanding marks left by the orbital sander.

6

Wipe the bumper with the damp rag.

7

Hold a can of well-shaken aerosol primer six to eight inches from the surface of the urethane bumper. Depress the tip of the spray can while constantly moving the can. Cover the entire bumper with an even coat of primer to prepare the bumper for paint.