Paint damage is an all too common occurrence that many vehicle owners decide to correct in a DIY manner. While patching and repainting a small damaged area can be a simple process, making the patched area indistinguishable from the original paint can be a difficult. For best effect, you'll need to pay close attention to detail, carefully tending to each paint layer until you build up a coating that matches the original not only for colour but for thickness, as well. A mistake in the process can make the patch obvious, marring the appearance of the car. Done properly, your patch will blend in smoothly with the surrounding surface, retaining the beauty of an undamaged paint job.
Mask off areas around the patch that you don't wish to paint using newspaper secured to the car body with masking tape.
Sand the patched area level using 220-grit sandpaper. Wipe the area with a tack cloth to remove the sanding residue.
Paint a layer of sandable polyester primer over the patch with a brush. Wait two hours for the primer to dry. Apply a second primer coat onto the first, allowing it two hours' drying time, as well.
Sand the primer smooth using 220-grit wet/dry sandpaper. Wipe the area with the tack cloth to remove the sanding residue.
Using a spray painter, spray a thin layer of paint over the primer. Wait one hour and then sand the paint smooth with 400-grit sandpaper, being sure to remove any flaws in the painted surface. Wipe with the tack cloth and then apply another thin layer. Continue the paint/sand cycle until you build the paint covering the patch to the same level as the surrounding car paint.
Add one more level of paint, this one overlapping the surrounding non-patch paint by about an inch. Sand away the clear coat protective layer from the non-patched paint with water saturated 2000-grit sandpaper before applying the overlapping paint. Wait 1 week for the final layer of paint to dry.
Sand the final coat of paint and the area bordering the patch with water saturated 2000-grit wet/dry sandpaper until you've lowered the area to the same level as the surrounding paint, blending the patched paint with the surrounding paint in the process. Wipe with the tack cloth and then spray a new clear coat layer over the patched and surrounding area. Wait overnight for the clear coat to dry.
Sand the clear coat with the saturated 2000-grit wet/dry sandpaper until the coat is smooth over the patch and surrounding area and blends seamlessly into the surrounding paint.
Wash and wax the car to further blend the patched area with the old painted area.
Wear safety goggles and a face mask for protection against particles resulting from the paint sanding process.