They key to rust removal is to get rid of it entirely — if you don’t, it will come back with a vengeance, and since it’ll be beneath a new layer of paint you might not see it until it’s already well-established. This job may be best done by a car paint repair specialist, but DIY-ers who are stout of heart or have experience doing similar jobs themselves may be able to do the work required.

Mask Off the Rest of the Car

First things first: You will need to protect the rest of the car from the body work you are about to do. In order to do this, use tape and paper to mask off everything but the rest and the immediate area around it. Don’t mask too close to the area you are going to eventually be repainting, though, or you will end up with a very distinct line at the edge of the car paint repair. Do be sure you do a thorough job with this, and don’t forget to roll up your windows. Sanding to remove the rust will cause a lot of fine dust that has a tendency to get into everything that isn’t covered up. Paint over-spray is notorious for the same thing.

Remove the Rust

The rust will need to be sanded or ground away from the metal to ensure that it is removed entirely from the vehicle. To do this, you can use a grinder or a dual action sander — or, if the rust is only on the surface, you might be able to hand sand the area using a sanding block. You can and should expect to remove a lot of paint during this process. Take the area all the way down to bare metal, making sure that all rust is gone before you consider the job done.

Use Filler to Create a Smooth Surface

If your surface has become uneven or pitted because of the amount of rust you’ve had to remove, you can use a filler to restore the original lines of the body panel. Simply apply the filler, being sure to use more than you actually need. Once it has dried, use a sanding block and hand-sand the excess filler away, checking frequently with both your hands and your eyes until you achieve a smooth surface.

Primer and Paint

Once the rust is gone and any dents or divots are smoothed over with filler, you will need to replace the layers of primer and paint that you have removed in order to remove the rust underneath. Modern cars have three basic layers of paint: primer, the colored layer of paint, and clear coat topping it all off. Any car paint repair job must replace all three layers before the work is done, or your car will be vulnerable to even more rust.

  • Primer: Apply the primer in thin, even coats, waiting a little while between coats to allow the primer to become tacky. You can also lightly sand between each layer with a fine grit sandpaper, to remove dust and debris that has stuck to the drying paint, and to create a smooth surface again.
  • Paint: The paint you use should be matched exactly to your car’s color, using the code on the inside of your door jamb, or the repair will be glaringly obvious. “Close” is not good enough here! Again, make each coat thin and even, or the paint will run.
  • Clear coat: This is just the clear, topmost layer that car paint repair job from scratches and other surface damage. This layer should also be applied with multiple thin coats.

Finishing Up

Once you have finished painting, you can use a polishing compound and a rotary buffer to create shine and smooth away any last rough edges around your repair. Wait 30 days before waxing, however, to allow your car paint repair job to finish curing. If the rust was fully removed and the area properly sealed with new primer and paint, the rust shouldn’t come back in that area.
ColorMate Auto Appearance Specialists provides same day car paint repair services including paint perfecting, paint and bumper repair, headlight restoration, rim repair, and car interior repairs in Miami-Dade, Broward and West Palm Beach County. Schedule an appointment for a free estimate on quality car interior and exterior cosmetic repairs.