Painting Defects

Poor Opacity

Description of problem:
The old paint or the ground coat is visible underneath the  topcoat.
 
Causes:         
Paint was not stirred well.
Paint is over thinned.
Thinner is too slow which makes the paint run before the required thickness is achieved.
Thinner used is incorrect.
Not enough spray passes (too low film build).
 
Preventive measures:
Stir the paint well.
Use appropriate thinning ratio.
Use appropriate thinner.
Spray sufficient topcoat to obtain opacity.
 
Remedy:
Allow drying fully.  Sand and