Description of problem:
Excess paint applied on a vertical or inclined surface does not hold and runs along side the panel.
Causes:
Spray gun too close to panel.
Spray pass is too slow.
Wrong spray gun setup (nozzle too wide or air cup too small).
Low air pressure.
Incorrect viscosity.
Bad application conditions (it is too cold or air circulation is lacking).
Not enough flash off times between coats.
Thinner too slow or too much retarder is used.
Hardener is too slow.
Paint is sprayed over dirty or oily surface.
Temperature of paint is too low.
Preventive measures:
Use correct hardener and thinner.
Ensure that spray gun is in good working order.
Warm object and material up to room temperature.
Use correct air pressure.
Avoid thick coats and observe flash off times.
Allow some time before turning up the temperature in the spraybooth.
Remedy:
Sand and polish.