After the HVLP car painting paint film dries, milky white mist or dull spots will appear on the surface.
1. The HVLP car painting process and the environmental humidity are too high, or there is moisture in the air compressor; if the environmental humidity is too high, a small amount (not more than 15%) of white water can be added for spraying. Drain the water in the compressor before spraying the car.
2. Improper use of thinner, too fast volatilization will cause the surface temperature of the paint film to drop sharply, causing water vapor to condense on the paint film.
3. Use compressed air to blow the paint film in an attempt to accelerate the volatilization of the solvent.
4. There is draught in the paint spray room of the car, or it is hot, and the air flow is not sufficient.
1. When possible, avoid spraying the car in rainy, cold or humid weather, and let the paint film dry naturally, otherwise, use non-fogging thinner.
2. Use good-quality diluent or appropriate-grade diluent.
3. Reduce the pressure of compressed air to reduce the cooling effect.
4. Ensure proper ventilation and heating in the car painting room to avoid draughts.
1. When the paint film is slightly fogged, it can be repaired by polishing after the paint film is completely cured to restore the gloss of the paint film surface.
2. When the paint film fogging is serious, the surface of the paint film can be smoothed, and then re-sprayed with a suitable grade of thinner or non-fogging thinner. If the above method does not work, you can increase the temperature of the car paint booth by more than 5°C to avoid direct blowing through the wind, smooth the defective parts, and then paint again.
3. If the whitening is produced in the varnish (whitening of the silver primer surface), it should be thoroughly polished and resprayed.