Powder paint is a dry, colored powder that is sprayed onto a steel structure by using a special application gun that uses air to discharge the powder. The special powder paint is positively charged while the material the powder is being applied to is negatively charged, causing the powder to stick to the steel. Once covered in powder paint, the item is placed into a large, specially-designed oven and baked for a time specific for the type and color of powder used. Once baked and cured, the result is a durable and very tough finish that resists cracking, scratching and dulling. The finish can be maintained, much like traditional paint, by washing and waxing.
Due to the method used to cure the powder paint, entire body panels are not usually finished with this type of coating. Typical candidates for the powder paint are chassis, wheels and other smaller steel components. Roll cages and motorcycle frames are also fine projects to use powder paint on. The finish is very thick and very hard to remove, making the taping of threaded holes and other areas that paint is not wanted on very important. It is also very crucial that even coverage is achieved as the blending and touching up of powder paint is very difficult.
Surface preparation is as critical with the powdered version as it is with traditional paints. Grease and oil must be removed from any surface with a quality remover to promote proper powder adhesion to the steel surface. Once the powder has been applied, it is important that the parts be placed in the oven and cured as soon as possible. This will lessen the chances that the powder will be touched and rubbed off of the steel. The powder will melt in the oven, creating a liquid that will flow out evenly and fill any small voids or cracks in the surface of the steel.
Once cooled, the powder paint becomes a hard finish that is resistant to scratching and chipping. The thick finish is often responsible for making tight-fitting components very tough to assemble. It is sometimes necessary to scrape or sand some of the finish away to enable the parts to fit together when reassembling some components. While this type of finish is favored by many race car builders, it is often a problem when an accident requires the frame or chassis to be welded. In order to weld on the cured powder paint, the finish must be ground away.