Preparing to Spray and Determining the Paint Over Which You Will Be Spraying
There is a lot to do before you can actually begin spray painting and putting the final finish on your vehicle. Here are some important tips.
The biggest concern of any spray painter is dust. Therefore it is worth your while to take the time to thoroughly remove any dust from the area in which you will be painting. Start by vacuuming the ceiling areas, including the ceiling supports, the walls and any other areas where dust can accumulate. Move any equipment such as automotive gear out of the work areas, then sweep and wash the floor thoroughly. (If you are on a pro track, it may be worth your while to paint your floor with a professional floor paint. If you do, dust and dirt will be less of a problem in the future.) Make sure to remove all dust from work benches, hand tools, lamps, and other things in the work area, too.
You will to find out what paint you are spraying into before you begin. You cannot spray just any paint over the top of another; doing so might cause a reaction that will result in crazing and cracks. To avoid this, you need to find out what paint was used originally on your vehicle. This information is sometimes on a color code tag on the vehicle itself (but on older vehicles it is often absent). Contact the manufacturer if this is possible to find out exactly what paint was used.
If you cannot find out the original paint or if the vehicle has been repainted, there are a number of ways to determine the finish. You can take the vehicle to a body shop and have someone there look at the finish. Their experience can often tell you the paint used.
Chances are, like most sprayers, you will opt for "cellulose" type paints. You can test the finish by taking some cellulose thinner and rubbing on an inconspicuous part of the vehicle, like the bottom of a door or a wheel well. If there is a reaction, it will happen quite quickly.
If you find there is a reaction, you will want to strip the paint down to bare metal, at least strip to bare metal all areas where a reaction is apparent. Another concern is if there are many coats of paint on the vehicle already. You can avoid crazing in this case, too, by stripping down to bare metal.
Here are some other tests to determine the type of paint on you vehicle. Rub the paint with a rag soaked with cellulose thinner in an inconspicuous area. If color comes off on the rag, you have acrylic or cellulose paint. If the paint strongly reacts with the surface, you have old oil-based enamel. If the paint gives you no reaction, you have high-bake acrylic or synthetic enamel.
You can also rub the paint with a cloth dipped in polishing compound to find out the finish that is on top of the paint. If the paint color comes off on the cloth, you have a normal paint finish. If it does not, you have a basecoat and a clear top coat.
Determining what type of paint and finish is on the vehicle will definitely help you determine what type of paint to repaint with and will save you a lot of time and energy versus the trial-and-error method.