BMW World - Bumper Repair

You've been out running errands and, upon returning to your car in the parking lot, you discover that somebody has "kissed" the bumper of your car, leaving an ugly scrape. The perpetrator is nowhere in sight, and an insurance claim isn't feasible since your deductible is higher than the cost of the repair. The size of that ding, though, is way larger than a touch-up brush could handle, so your only option is to use some rattle-can spray paint to cover it up.

Color-Coding
Paint repairs are not all that difficult, but require some preparation and patience. First, you need to get the color code for your car. Your local car dealer or auto parts store should have it on their computers, or look in your owner's manual to locate the spot on your car where it's been imprinted. If your dealer doesn't carry spray paint, most parts stores have a spray-paint section with a reference book listing your car's correct tint.

For this particular project we weren't able to find the exact code in the book, but the color on the cap seemed to match the paint, so we took a chance. Note, however, that even when you do find the right code, if your car's paint is oxidized at all, don't expect your patch to match exactly anyway.

Supplies & Steps
While you're at the parts store, you'll also need to get some spray-on primer, clear coat, masking tape and wet-or-dry sandpaper (400 grit, and perhaps some lighter and coarser grades depending on how much prep and finish work you'll need to do).

The basic procedure is pretty simple, though a bit tedious (click on the Step Photos for details). When sanding the damaged area, take your time. With bodywork, preparation is 99 percent of the job. You may need to repair nicks or dings with some body filler to get a really smooth finish. Feeling the surface with your bare hand is the best way to tell if the contours and surface are smooth enough. Don't rub in one spot too long, or you'll create an uneven surface.

When you're ready to spray on the primer, make sure the temperature and humidity are in the correct range as indicated on the can's label, and use a gentle sweeping motion. Apply several light coats and let each one dry before spraying on another. Also, sand away any drips or bubbles between applications. Use the same spray technique for applying the color coats. You'll probably end up with slight ridges at the edges of the masking tape, so after the paint dries thoroughly, use some rubbing compound to smooth out the patch. If that doesn't work, try some very fine sandpaper on the edges, and then follow with a light feathering to blend in the patch with the surrounding area.

Step by Step Instructions


Step 1 Thoroughly wash the damaged area and remove any grease or oil.


Step 2 Sand the area in several directions, but avoid rubbing on one spot for too long.


Step 3 Check for smoothness of the sanded contours by rubbing your bare hand over the surface.


Step 4 After you're done sanding, wash the area once again to remove any residue.


Step 5 Mask off the area to be painted with heavy paper (newspaper is probably not thick enough).


Step 6 Spray the primer on in several light coats. Don't get too close to the surface or you'll get drips.


Step 7 Sand between coats of primer to remove any drips or other imperfections.


Step 8 Once you're satisfied with the smoothness of the surface, apply a final coat of primer and let dry for about 30 minutes.


Step 9 As with the primer coats, apply the color coats in several light applications.


Step 10 After peeling away the masking tape and paper, you may find a slight edge on the patch. Rubbing compound may remove it, or use very fine wet-or-dry sandpaper and then feather in the borders with a light spray.


Step 11 A final layer of clear coat can be sprayed on if you want to match the paint as closely as possible.