CAUSES: Incorrect rolling technique. Frequently, the use of an incorrect roller cover with an excessive nap length. Over loading the roller cover with paint. Failure to spread the paint uniformly. Paint over a slick surface without proper priming.
SOLUTIONS: Cover with the correct nap length. Make certain the roller is rolling, not sliding. Begin with an upward zigzag stroke in an “M” or “W” pattern and fill in the pattern with parallel strokes without the surface.