Sanding and polishing the lacquer topcoat adds to the glossy finish of your automobile, but it is a time consuming process. You may need to put in over 40 hours of labour from the start to the finish of the project. The time spent, however, creates a smooth, even surface that makes the paint job look cleaner and creates a reflective finish that’s nearly mirror quality. Done correctly, it makes the difference in looks that takes your car's paint job from ordinary to show-car quality.
Begin with an absolutely clean, newly painted automobile. Wipe the surface of the lacquer with a wet rag in order to remove any dust or dirt that may have fallen onto the vehicle.
Place 1500 grit sandpaper onto a flexible sanding block. Go over the surface of the vehicle with the sandpaper, removing any imperfections in the paint such as lines or uneven surfaces. Using the block should prevent distortion of the surface of the sandpaper, which can create an uneven surface in the paint. Continuously wet the surface of the automobile as you sand it, using the hose.
Go over the surface of the vehicle with successively finer grits of sandpaper working your way up to 2000 grit. Create a smoother surface on the paint with each successive pass of the sandpaper. Take care at corner areas or raised ridges in the automobile as these areas have the thinnest layers of applied paint. Sanding through the topcoat of paint to the undercoat will require that you repaint the vehicle and begin again. Allow the car to dry after the last application of sandpaper.
Mount a wool pad to a power polisher for buffing the rubbing compound into the car’s finish. The wool pad allows greater airflow when buffing, which keeps the pad cool. This reduces the chances of burning through the topcoat to the paint below.
Apply rubbing compound to the automobile by placing a coin sized pool of compound onto a clean rag and spreading it onto the car. Spread the compound evenly over the flat surfaces of the automobile and apply a slightly thicker layer onto the raised edges to avoid polishing through the thinner paint.
Set the polisher to 1,400rpm and buff the rubbing compound with the wool pad. Use straight even horizontal strokes, covering a single auto body panel at a time. Buff the entire vehicle until it shines. Always polish along the body of the automobile, never across the ridges, to avoid rubbing through to the paint beneath.
Apply the polish to the car using a soft lint free cloth.
Switch to a foam pad on the polisher and set the polisher to 1,000rpm to control the greater heat generated by the foam. Polish the surface of the automobile using the same process of coverage as used with the polishing compound.
To speed up the sanding process, use an orbital sander.
Orbital sander use can quickly scratch the surface of the car requiring repainting if a slip is made.