In the past, people thought painting and applying a clear coating to their car bumper was a good idea. If you have a vintage or classic car, multiple coats on your bumper can look messy. There are a few options on how to remove clear coatings from your car bumper. This method is inexpensive and does not require any machinery. Try these steps first before turning to a professional for help.
Step 1 - Prepare
Place a drop cloth underneath the bumper of your car. The hand sanding you will be doing will create dust and sand particles. Cleaning up afterward will be much easier if you have a cloth underneath where you are working. Also, make sure you are wearing a protective mask so that no irritants enter your nose or mouth and also protect your hands with gloves. You may also want a pair of goggles to shield your eyes.
Step 2 - Sand
Sandpaper is great at scratching the clear coat off your car bumper. Start with the lowest grade sandpaper first, in this case the P320 grit paper. It is coarse and will be able to cut through the thickest layers of clear coat. As you get closer to the actual bumper you should switch to the finer sandpaper so that you minimize the risk of scratching your car bumper.
Move the sandpaper in manageable strokes in the same direction. Don't make your strokes too long so that you can concentrate on a small piece of the bumper at a time for optimal control.
Step 3 - Clean the Sandpaper
Every so often stop sanding and inspect the coarse side of your sandpaper. There could be bits of clear coat lodged in between the grains of the sandpaper which would render it ineffective. Dislodge the errant debris either with a cloth or brush.
Step 4 - Change Sandpaper
After you have sanded the bumper once with the P320 grit sandpaper, make sure you notice a difference in the thickness of the clear coat. Then move on to using the P500 grit paper and sand the bumper again. If after the second round of sanding you don't see much difference, go back to using the coarser paper but be careful of over-sanding. Once you feel that you are getting close to the bumper but still have some clear coat on it, switch to the P800 grit paper. This is very fine sandpaper and can eliminate a thin layer of the clear coat without going too far. It may be hard at first to know when to switch sandpapers but proceed with caution and opt for the finer sandpaper if you're getting nervous about damaging your car bumper.
Don't think you have ruined the project if your sanding has affected the paint job; it is normal to have to finish this process with a new coat of paint. You could go with the old color or update the look of your car by going with a new color.