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Paint Defects

Dry Spray

Description

A granular or coarse texture finish with no gloss

Cause

Paint being deposited on the surface in a powdery condition.
  1. Viscosity of paint too high, use of incorrect or poor quality thinner.
  2. Poor spraying technique, dirty spray gun, compressed air pressure too high, gun held too far from the surface during spraying.
  3. Spraying in draughts or in a high velocity airflow.

Prevention

  1. Use the correct proportion of recommended thinner.
  2. Use correct spraying techniques, ensure that equipment is clean, set air pressure as low as possible, consistent with proper atomisation, spray from the correct distance.
  3. Use a spray booth, and ensure that air circulation and extraction is at the correct velocity.

Rectification

Flat, compound and polish. If texture is too coards for this to correct the defect, rub down the top-coat and repaint. Metallic finishes must always be rubbed down and repainted.