Removing a Black Scrape on a Car

Here’s the black scrape early in the process of removing it.

While visiting my son and daughter-in-law, I noticed that she had a pretty ugly black scrape on the side of her car. She had gotten it when she backed out of a tight parking space and rubbed up against the plastic back bumper on a truck.

I decided to win points by removing it.

I had to decide between two methods, abrading it off or dissolving it off. Both came with risks. Abrading would leave scratches and might abrade through the white paint. Dissolving could also dissolve off some of the white paint if I used the wrong solvent. So I ruled out acetone and lacquer thinner, even though I was pretty sure the modern paint and clear coat wouldn’t dissolve in these solvents.

In progress, forgetting the protective gloves.

I settled on naphtha because it also dissolves plastics. It required a little more elbow grease, but it is entirely safe to use on any finish except the typical water-based finishes you find at home centers. Naphtha will soften and could damage these finishes.

So here are before, during and after pictures. By the time I realized that I should take some pictures, I had already removed about half of the damage, and I forgot to put my protective gloves back on for the posed shot.

I apologize for this. You should always wear protective gloves when getting solvents on your hands.

The black scrape removed.

— Bob Flexner

Want to learn more about finishing from Bob Flexner?
Check out his book “Flexner on Finishing,” at shopwoodworking.com