Small chips and scratches in the finish on your collector car can turn into a big problem if left unattended. Minor paint damage of this type can be caused by carelessness, road debris, normal wear and tear, and unfortunate incidents. For example, recently a rear wheel cover flew off my ’53 Pontiac Catalina, bounced onto the ground and rolled back into the door, causing three scratches in the paint.
If the chip or scratch leaves the primer under the paint intact, the damage will be purely cosmetic. If the paint and primer barriers are both broken, bare metal will be exposed to the elements and rust will set in. The small chip can become a big problem if you don’t touch up the minor damage right away.
Paint touch-up isn’t a difficult procedure, but if you want a high-quality repair, it’s important to perform all steps carefully. Trying to rush is probably the biggest reason that touch-up painting doesn’t come out well. Blending in new paint to match the old paint around a chip is a job that requires slow, meticulous, step-by-step procedures.
First, using a sheet of 80-grit sandpaper, sand the chipped area by hand. You’ll probably notice some surface rust. Keep sanding until all the metal is clean and shiny. Use a suitable tool or the tip of one finger to press the sandpaper onto the chipped spot. Go either back and forth or round and round, depending on your preference. Sand a small amount of the paint surrounding the chip, so that there will be “bite” for your primer and touch-up paint. They won’t adhere well to a smooth, painted surface with car wax on it.
After sanding, clean the area in and around the chip with a prep solvent and a tack cloth. After tacking the spot, the next step is to prime coat the area. A good technique for spraying primer on a small chip is to use a large piece of cardboard as a “screen.” Make a hole about twice the size of the area you want to prime in the center of the cardboard. Test spray to see how much paint gets through your hole. The idea is to hold the screen a few inches away from the damaged area so that it’ll allow the primer to reach only the chipped area. For larger scratches, masking the area with masking tape and sheets of newspaper may work better.
After the primer coat dries, sand the repair area lightly with 400-grit sandpaper. At this stage, you’re not removing the primer to get to bare metal again. All you want to do is lightly scuff the surface so that the paint will adhere to the primer. After you’re finished sanding, hit the repair with your solvent and tack cloth again.
Now you’re ready to apply a top coat with your touch-up paint. If the car being worked on is a newer model, like an exotic, you can get the proper touch-up color from a car dealer, an auto parts store, a body shop supplier or even the automotive department in a discount store. These stores have booklets that tell you where to find the paint codes on your car and how to match them with duplicate colors. For older cars, Tower Paint (www.towerpaint.com) will custom mix the proper touch-up colors for most vehicles (including foreign models) from 1930 to present and put them in a spray can for you.
When you get the proper paint, spray several light, thin coats on the damaged area through the hole in your cardboard screen. Allow each coat to dry completely before adding a new one. If you have masked the area off instead of using a cardboard screen, leave the masking tape and paper in place for several hours. Most hobbyists are anxious to remove these materials to see how the repair came out. Jumping the gun can ruin the job.
When you’re finished removing your masking materials, allow the paint to dry for at least two days (recommended times very from 24 hours to 72 hours, but 48 hours is a good average). It is hoped that everything will come out pretty good, but you’ll still have to “work” the paint to blend it in properly. Use a small amount of rubbing compound on a soft, clean moist rag to “rub out” the repair. Rubbing compound goes on like wax, but is much more abrasive.
Dip a soft folded cloth or foam pad into water, wring it out and dip it into the rubbing compound. Now rub the compound on the repair with a back-and-forth motion. Do not use a circular motion! Patiently use the compound’s abrasive qualities to “feather” the new paint and old paint together until the repair is nearly imperceptible. Do not rub too hard because rubbing compound actually removes the finish. Stop when the border between the old and new paint can hardly be seen. Wipe off any remaining rubbing compound. Then, wax the car.
The Eastwood Company (www.eastwoodco.com), a supplier of restoration tools and products, offers two specialized paint chip repair kits for touch-up work. The kits are said to make the touched-up painted areas more closely resemble the factory texture of the surrounding paint. This may be something to investigate if you’re trying to preserve an old car’s original factory finish so that it can qualify as a “Historic Preservation” class vehicle.
John “Gunner” Gunnell is the automotive books editor at Krause Publications in Iola, Wis., and former editor of Old Cars Weekly and Old Cars Price Guide.