Basic Auto-Body RepairGetting rid of scratches, dents and rust
Whether your daily driver is a used vehicle that came with its own set of dings and scratches, or you've just suffered the first assault of an errant shopping cart on a new auto, don't worry. Repairing minor body damage is neither a difficult nor intimidating task. With the help of conventional workshop tools (such as a sander and an electric drill) along with a little elbow grease and some common supplies from your local auto parts shop, these scratches and dings can all disappear.
The first step for any body repair process is to start with a clean car, using automotive cleaning products followed by a good bug and tar remover to remove the layers of wax, grease, and deposits. The techniques for a body repair are more a matter of finesse and touch than muscle. Also, take the time to read the instructions on your body repair kit (screen, putty, primer and touch-up paint) for curing and drying times. We'll start with repairing simple scratches:
Using very fine sandpaper (one designed for wet sanding) and a water-soaked sponge, feather the edges of the scratch, going to bare metal if necessary. What you're looking for is a smooth taper from the scratch to the unmarred paint. You know you're there when you can run your finger lightly over the area without feeling even a trace of an edge.
If the scratch is deep, you can fill it with body putty or filler. The best way to determine if body putty is required is, again, to run your hand over the area. Unless you've got a practiced eye, just looking at the area is deceptive. Your fingertips and palm are your best tools. Wet-sand the putty to blend the edges.
Make sure the area surrounding the damage is masked off-at least three inches is good-to ensure a good blending of the repair coat. Apply the primer and wet-sand the area with extra fine sandpaper and your wet sponge for the best bonding of the final paint.
Auto manufacturers make it easy to match the original paint with color codes and touch-up kits available from auto supply shops or the local dealer. Once the final color has been applied and dried, do the final sanding with 1000-grit wet sandpaper. Once you're sure the paint is completely dry, use rubbing compound to bring up the shine on the new paint.
For rust, the most important thing to remember is to eradicate all the corrosion on your first try. If you don't, you'll be chasing that same rust spot for the life of the vehicle or the rest of your life, whichever comes first. Here are the basic steps to follow:
Grind the rust down to bare metal. An orbital, or circular, sander is the best tool for this job, but it can be done by hand. Again, your goal is a taper from the rust area out to clean metal out to good paint.
Here's where the electric drill comes into play. Drill holes around the area beyond the original rust spot, forming a base for the body repair screen. Cut the adhesive-backed repair screen to fit over the rust area but within the drill holes. Put the repair screen in place.
Once the patch has cured, apply body putty, shaping and sanding for a smooth, seamless transition from the repaired area out to the original paint.
Follow the same finishing steps under "scratches" for the primer and final paint-don't neglect the fine wet sanding between steps.
Repairing dents is a somewhat tougher do-it-yourself repair job. If there are sharp creases in the metal, your chances of a flawless repair are slim, especially if this is your first project in the world of body repair. But if the edges of the dent are "rolled" and you've mastered the body putty techniques, it's worth a try. If you don't want to cough up the money for a slide hammer, the tool used by body shops to pop out minor dents, here's a trick that works almost as well.
> Drill a 1/16-inch hole in the center of the dent.
> Insert a metal screw in the hole; grip the screw with a set of pliers and pull. The metal should pop back to something closely resembling its original shape.
> Now, go back to the steps under "scratches" and "rust," feathering the area with sandpaper, removing any rust, applying the body putty, primer and final paint with fine grit wet sanding in between all the steps.
Admire Your Work
The last step for do-it-yourself body repair jobs is to stand back, admire your work and pat yourself on the back. You've invested a fair amount of time and energy in the project, but you've also saved yourself some serious money.