What causes small pits after car painting?
2 Answers
It is due to poor craftsmanship. The surface should first be repeatedly sanded with wood sandpaper to remove wood burrs and make the surface smooth. Any residual glue at wall joints and other bonded areas should be scraped off with a knife or sanded off with fine sandpaper. If there are color spots or uneven color distribution on the surface, the surface should be pre-treated for decolorization to achieve uniform color. The details are as follows: 1. Repeated painting: The surface of metal components should be thoroughly cleaned of dust, oil stains, welding slag, and rust spots, then coated with anti-rust paint. If not specified in the drawings, the coating should be applied at least twice. 2. Paint selection: Choosing paint for an air-powered mixer requires consideration of multiple factors such as power type, applicable materials, layout form, processing capacity per batch, type of air-powered mixer, material type, application field, mixing method, and air-powered capacity. For example, applicable materials include liquids, paint, chemicals, food, adhesive, ink, etc.; application fields include chemicals, construction, food, medicine, paper industry, etc.; layout forms include horizontal, vertical, cycloidal, coaxial, etc.
I've encountered this situation before, mainly due to insufficient surface cleaning during the painting process, especially dust, grease, or old paint residue left on the car body. After painting, dust particles mixing in can form small pits. Additionally, if the painting environment has high humidity or excessive dust, dust settling before the paint cures can also cause this issue. Holding the spray gun too far away or moving it too quickly during painting can result in uneven paint application, creating tiny bubbles or depressions. Improper paint mixing, such as adding too much thinner, can lead to uneven shrinkage after drying, forming pits. The key to prevention is thoroughly cleaning the car body in advance, sanding it smooth, and ensuring the workspace is enclosed and low-dust. After painting, don't rush to drive away; avoid touching the surface during the drying process. These small pits may seem minor, but leaving them untreated can accelerate paint aging, cracking, and even rusting. So, if you notice them, it's best to have a professional shop re-sand and repaint the area—spending a little money now can save you big trouble later.
