Once a car has been built, it goes to the body shop for a washing and baking/drying process. This has to occur before the chassis is painted. Professional teams have the advantage of large shops, paint rooms and bake booths, but for many, the steps are much less involved. In this section on paint prep, we'll begin with the sanding.
Whatever material was used for the car, it needs to be roughed up for the paint to stick. Sandpaper, sheet metal, fiberglass or plastic is used to scratch the surface lightly enough to leave a scuff. A light touch is required -- too much force could cause damage to the material.
Durability comes into play in the next step too, when the surface is gleamed up with an industrial cleaner. This gets grease off of the car's surface before the primer is set, and an "electrocoat" goes down to kill any electric transmission of sparks [source: Gibson, DuPont]. But again, overuse could wear down the foundation.
Once the body has been cleaned (and dried again), a primer, which serves as a buffer zone between the metal and the paint, is applied.
Filler might be applied as well, if the car's panels aren't "straight." To be straight means that the surface looks even, without bubbles or warped spots. Tools are needed to hammer out bent metal edges or otherwise redesign the problem area, but once that's done, a filler is applied, then sanded until smooth and perfect, to finish out the process.
So your car's ready and your paint is in stock. Cruise over to the next page to check out the application process.