Craters are circular dents with raised edges in the topcoat or the intermediate coats.
1. Oil, fat, wax and silicone polish residue were not thoroughly removed from the surface to be coated.
2. Contamination from the air, e.g. spray mist from another type of paint.
3. Oils or water from the compressed air.
4. Silicones from the aerosol cans (Water repellents).
5. Foreign substances from industrial plants near by.
PREVENTION Only a very thorough cleaning of the areas to be coated can prevent craters from forming. If products which contain silicone (polish, sealing compounds) are used this should be carried out in a separate area, totally away from the spray area.
REPAIR If craters have formed sand away this layer of paint thoroughly clean and apply a new paint layer.