By Steve Temple, automedia.com
Today's two-part urethane paints consist of a clear coat on top of the color coat. While this system preserves the color by protecting against UV rays and provides a brighter shine, it can also get scratched fairly easily. Just rubbing your rag on a dusty surface, or having grit in the cloth itself, can leave fine lines and swirls.
If polishing and waxing isn't producing the smooth finish you'd like to see on your vehicle, but you can't feel the scratches with your fingernail, then a simple liquid scratch remover might do the trick. Note, however, that not all car scratches are the same. Some marks may be due to rubbing against a bumper from a car or shopping cart. The material coming into contact with your finish might be softer, and simply leaving behind a bit of material on top of the paint.
If that's the case, it may come off easily with a spray for removing tar, bugs and adhesives. Be sure to use a product specifically designed for marks on paint, as acetone or types of solvents might damage the paint. If the mark is still there after using the spray cleaner, try using a soft-grade rubbing compound (it's easy to penetrate the clear coat, so don't overdo it). You'll need to use a polishing compound to remove any fine scratches left by the rubbing compound, and then finish the job by sealing the surface with a good car wax.
Medium-depth scratches that you can feel with your fingernail require a more aggressive method of repair than simply using rubbing and polishing compounds. Bad scratches that penetrate to the color coat can require touch-up paint and possibly professional care.
For the medium-depth scratches, use a car scratch remover kit. The system is fairly easy to use, requiring three separate steps and a common household drill. As with the rubbing compound mentioned above, less is more. The idea is to take off a very thin layer of the clear coat, but still leave enough on to protect the paint. And you'll need to protect the finish with a good wax or synthetic polish to bring back the shine.
Scratch removal tips