ApplicationQuestion 55 of 100
What typically causes 'runs' or 'sags' in a paint film?
a.Applying too little paint
b.Applying the coating too heavily so it flows downward before it can set
c.Painting in cold weather only
d.Using too short a nap
Explanation
Runs and sags occur when too much paint is applied in one pass and gravity pulls the excess down before it sets. They are prevented by applying proper film thickness, maintaining spray distance and speed, and back-brushing or back-rolling. Sags can be brushed out while wet or sanded and recoated once dry.
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