1. Improper viscosity of paint
2. Excessive film thickness
3. Using the Thinner which evaporates too slowly
4. Too short flash or dry time
5. Slow gun pass or the distance between the spray gun and surface is too short
6. Insufficient air pressure
1. Adjust the gun properly, from air pressure, spraying distance, to gun pass and etc.
2. Properly adjust the viscosity of paint. Use only the Thinner recommended by the manufacturer.
3. Allow sufficient flash and dry time between each coating
4. Avoid excessive application overlap. Allow ample flash and dry time between each spraying.
1. For few runs found after the surface is cured, wash off the affected area and sand with the Sanding Paper no. 1000-2000. Sand again with swirl remover and wax.
2. In extreme cases, use a blade to cut off the runs. Wash off the affected area and refinish.