Condition:

   A stripped or spotty appearance in metallic paints caused by the flakes floating together in the paint film.

 

Cause:

  1. Incorrect spray gun set-up.
  2. Spray gun distance from the surface is too close which is incorrect.
  3. Αpplication of basecoat is too wet
  4. Mixing or stirring of paint is not good enough
  5. Not sufficient time between base coat layers
  6. Using of fast evaporating thinner or reducer.
  7. Uneven spray pattern.

Prevention:

  1. Use proper gun adjustments, techniques, and air pressure.
  2. Select the thinner or reducer that is suitable, e.g., faster solvent in cold, damp weather; slower solvent in warm, dry weather.
  3. Mix all materials, especially metallics, thoroughly.
  4. Proper flash off time should be there in between the quotes.

Treatment:

  1. If mottling appeared prior to clear coat application, a light control coat (with lower air pressure, increased gun distance and further reduced base coat) will even out aluminum flakes.
  2. If mottling appears after clear coat application, sand and refinish with PCI alternative product list.