Blushing

Cause


  • When spraying during humid conditions, air from the spray gun and solvent evaporation lowers the substrate temperature below the dew point, causing moisture in the air to condense in or on the paint film. The condition is aggravated when too fast drying or unbalanced thinner/reducer is used.


Repair


Should blushing occur during application:


  • apply heat to the affected area, or add retarder and apply additional coats.
  • If the finish has dried, minor blushing may be corrected by compounding or polishing, how ever, severe blushing will require sanding and refinishing.


Prevention


  • Always use good quality solvent and thin/reduce material according to label directions.
  • Select proper thinner/reducer for spray condition.
  • Add the recommended amount of retarder when spraying in humid conditions.
  • Apply heat after application to evaporate moisture.