What Are the Steps for Car Painting?

[OThomas]

First, the damaged steel panel needs to be repaired through metalworking. Apply the first coat of rust-proof primer. Its main function is to prevent rust on the metal body, providing excellent protection for the steel and improving the adhesion between the base material and the topcoat. This is a crucial step in car painting, similar to laying a foundation. Apply a layer of body filler (commonly known as putty) over the primer. However, the putty used on the car body is metal putty, which costs several times more than ordinary putty. Maintenance shops use different types of body filler depending on the season. After applying the body filler, sand it down. Once sanded, apply a fine layer of filler (red putty or spot putty) to smooth out minor imperfections. Sanding is done using a specialized dry sander, and carbon powder indicator is sprayed and sanded to check for tiny defects before proceeding with further painting. Apply another layer of body filler, sand it, and then spray an intermediate primer. The intermediate primer enhances the adhesion of the topcoat and color paint while also providing anti-corrosion benefits. It further highlights any particles or impurities on the car body, making it easier to sand and repair. Apply carbon powder indicator again to check for minor defects and sand the intermediate primer to ensure the entire surface is smooth and ready for the next step. Spray the color paint. This step usually involves three coats. The first coat is a mist spray, applied quickly to create a thin, fog-like layer that helps the paint adhere to the intermediate primer. The second coat provides coverage, showing the color, and the spray gun can move slightly faster. The third coat corrects any unevenness or color spots from the second coat. The goal is to achieve uniform color coverage across the repair area or the entire car. After the color paint is applied, allow it to flash dry so some solvents evaporate, making the film dry before applying the first coat of clear gloss varnish. The first coat of clear varnish should be a light mist spray, not too thick, just enough to show a slight gloss, with the spray gun moving at a slightly faster speed. Use coarse wax to sand the surface, effectively removing the oxidized layer. Perform a mirror finish treatment on the car body. Apply a mirror finish compound to eliminate wax streaks and smooth the surface, then polish it with a polishing machine to achieve a glossy finish that reflects objects clearly. At this point, the standard painting process is complete. However, roadside shops and small repair shops often skip the protective primer layer to save time and costs. They usually sand only once and use water sanding, which can lead to hidden issues. If the water isn’t completely dry before painting, bubbles and cracks may appear in the paint later. They then patch with colored putty and start painting, saving materials and labor, but over time, the paint is prone to peeling.