Evident in metallics when all the aluminium particles tend to run the one way. Encountered mostly on vertical surfaces where the weight of the aluminium “drops” through the applied coat


  1. Applying metallics too heavily almost to the run and sag stage.
  2. Wrong thinning reduction.
  3. Wrong gun adjustment and technique.
  4. Insufficient flash time between coats.



  1. Do not apply in heavy wet coats.
  2. Use recommended thinning ratios.
  3. Use good spray techniques i.e. gun held at right angles 15-20 cm from the job with a constant gun speed over complete area.
  4. Allow recommended flash times between coats.



If silking has already occurred, sand with fine paper and refinish.



Other Defects: