Specifications

11
DEFECTS CAUSE CORRECTION
Coarse spray Low pressure Increase the pressure.
Excessive fogging High pressure Reduce the pressure to satisfactory pattern distribution.
(overspray) Material too thin Use less thinner.
Pattern too wide Spray angle too large Use smaller spray angle tip.
Pattern too narrow Spray angle too small Use larger spray angle tip (if coverage is OK, try tip
in same nozzle group)
Too much material Nozzle too small Use next smaller nozzle.
Material too thin
Pressure too high Reduce pressure
Too little material Nozzle too small Use next larger nozzle
Material too thick
Thin distribution in Worn tip Change for new tip.
center of pattern Wrong tip Use nozzle with a narrow spray angle.
"horns".
Thick skin on work Material too viscous Thin cautiously.
Application too heavy Reduce pressure and/or use tip in next larger nozzle
group.
Coating fails to Material too viscous Thin cautiously.
close & smooth over
Spray pattern irreg- Orifice clogged. Clean carefully.
ular, deflected Tip damaged Replace with new tip.
Craters or pock Solvent balance Use 1 to 3% "short" solvents remainder "long" sol
marks, bubbles (this is most likely to happen with material of low
on work viscosity, lacquers etc.)
Clogged screens Extraneous material Clean screen
in paint.
Coarse pigments Use coarse screen if orifice size allows.
Poorly milled pigments Use coarser screen, larger orifice tips. Obain ball milled
(paint pigments glocculate paint. If thinner has been added, test to see if a drop
cover screen. Incompatible placed on top of paint mixes or flattens out on the
paint mixture & thinners. on the surface. If not, try different thinner in fresh
batch of paint.
TEST THE PATTERN
Good, full Spotty
pattern. pattern
Increase Pressure.
AIRLESS SPRAY GUN OPERATION