Runs/ Sags

Cause

 

  •   Over reduction and/or too slow evaporating thinner/reducer.
  •   Applying paint materials without proper flash time between coats.
  •   Applying excessive wet coats due to:

      Holding the gun too close to the surface

      Slow gun speed

      Double coating

  •   Air pressure too low during spray application.
  •   Improper spray gun set-up or an unbalanced spray pattern.
  •   Material and/or substrate temperature too cold.



Repair

 

  •   Remove the wet paint film with solvent, clean and refinish.
  •   Or, after finish is completely dry. remove excess paint by block sanding with 1200 or finer grit sandpaper, compound and polish to restore gloss.
  •   Or, block sand smooth and refinish.



Prevention

 

  •   Mix according to product directions. Select recommended solvent for spray conditions based on temperature, humidity, air movement, size of repair.
  •   Spray medium wet coats and allow sufficient flash time between coats.
  •   Adjust the spray gun for the best atomization and balanced spray pattern before paint application. Hold the spray gun perpendicular and parallel to the panel. Adjust speed of pass, pattern overlap, and distance from the panel until the desired results are achieved.
  •   Set air pressure at the gun according to product recommendations.
  •   Use recommended spray gun, including fluid tip and air cap combination.
  •   Allow the paint material and substrate to reach room temperature before application.