How to Apply Automotive Paint

Automotive paints have been made from a number of different materials over the last century. Early vehicles were painted by hand using Indian enamels but these were prone to fading. Nitrocellulose colors became popular in the 1920s, and after World War II acrylics became the paint of choice throughout the automotive industry. In the modern age, the demand for lower volatile organic compound (VOC) emissions has led to a surge in popularity for water-based paints. However, the majority of water-based materials are still covered with a protective clear coat that is often acrylic-based.

Instructions

1

Activate the water-based paint at a ratio of 10 parts of paint to 1 part of water-based activator and stir the components together thoroughly. Transfer the mixed material into a gravity-fed spray gun with a 1.4mm fluid tip and a 120-grade air cap. Degrease the auto body panel and remove loose fibers with a tack cloth before painting begins.

2

Plug the spray gun into an airline and position the nozzle to the bottom left-hand corner of the auto body panel. Ensure the paint pot is pointing directly upward to maintain the correct spraying angle of 30 to 45 degrees. Keep the nozzle 4 inches away from the surface of the panel and set the pressure gauge to a maximum of 2.2 bar or 32 pounds per square inch. Ensure the spraying temperature is set at approximately 68 degrees Fahrenheit.

3

Pull back the trigger of the spray gun to release air pressure and promote paint atomization. Begin to move the arm slowly from left to right in a single horizontal movement, ensuring the speed is sufficient to produce a wet coat of paint. Take care not to move the arm too slowly or the paint will run. Do not move the arm too quickly or the paint will have a dry and gritty appearance.

4

Continue pulling the spay gun trigger until you have reached the opposite end of the auto body panel. Release the trigger once you have completed the first horizontal movement, then lift the gun into a higher position so your next horizontal movement, which will pass from right to left, slightly overlaps the previous one. Ensure overlapping occurs to prevent dry edges or streaking in the paintwork. Pull back on the spray gun trigger and complete another full horizontal movement.

5

Repeat the process, working from left to right and back again, until the entire surface of the auto body panel has received an even coverage of paint. Remember to move upward slightly after each horizontal stroke has finished. Allow the first coat to cure for 10 minutes before applying a second full coat in the same fashion. Allow the second coat to cure for 10 minutes before applying the third and final coat.

6

Position the spray gun at a distance of 8 to 12 inches for the final coat. Pull back the spray gun trigger and move the arm slightly faster to apply a lighter drop coat that promotes uniform coverage and superior distribution of metallic content (if applicable). Carry out a visual check on the applied paint to ensure there are no signs of transparency, run or sags. Allow the final drop coat to cure for 5 minutes before applying protective clear coats.