Airless Spray Gun Troubleshooting - AIRLESSCO HSS 9000 Manual

AIRLESS SPRAY TROUBLESHOOTING
DEFECTS
Coarse spray
Excessive fogging
(overspray)
Patten too wide
Pattern too narrow
Too much material
Too little material
Thin distribution in center
of pattern "horns"
Thick skin on work
Coating fails to close &
smooth over
Spray pattern irregular,
deflected
Craters or pock marks,
bubbles on work
Clogged screens
Excess paint builds on
tip guard
Drips, spits from tip
Tip clogs continually
TEST THE PATTERN
GOOD, FULL SPOTTY PATTERN, INCREASE PRESSURE
CAUSE
Low pressure
High pressure
Material too thin
Spray angle too large
Spray angle too small
Nozzle too large
Material too thin
Pressure too high
Nozzle too small
Worn tip
Wrong tip
Material too viscous
Application too heavy
Material too viscous
Orifice clogged
Tip damaged
Solvent balance
Extraneous material in paint
Course pigments
Poorly milled pigments
(paint pigments glocculate)
Spray gun too close to
surface
Pressure setting too high
Valve seat and/or ball in gun
head damaged or worn
Debris in paint
Gun filter missing
Coarse filter mesh
CORRECTION
Increase the pressure
Reduce the pressure to satisfactory pattern distrabution
Use less thinner
Use smaller spray angle tip
Use larger spray angle tip (if coverage is OK, try tip in same
nozzle group)
Use smaller nozzle
Reduce pressure
Use next larger nozzle
Material too thick
Change to new tip
Use nozzle with narrow spray angle
Thin cautiously
Reduce pressure and/or use tip in next smaller nozzle group
Thin cautiously
Clean carefully
Replace with new tip
Use 1 to 3% "short solvents remainder "long" solvents
(this is most likely to happen with material of low viscosity,
lacquers, etc.)
Clean screen
Use coarse screen if orifice size allows.
Use courser screen, larger orifice tips. Obtain ball milled
paint. If thinner has been added, test to see if a cover
screen. Incompatible drop 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.
Hold gun further from surface sprayed
Reduce pressure setting
Service spray gun, replace valve assembly
Thouroughly strain the paint before use
Do not operate without inlet strainer
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