LG Electronics 3600 Spray Gun Troubleshooting, Defects Cause, Test the Pattern Correction

Spray Gun Troubleshooting

DEFECTS	CAUSE
Coarse spray	Low pressure
Excessive fogging	High pressure
(overspray)	Material too thin
Pattern too wide	Spray angle too large
Pattern too narrow	Spray angle too small
Too much material	Tip size too large
	Material too thin
	Pressure too high
Too little material	Tip size too small
	Material too thick
Thin distribution in	Worn tip
center of pattern	Wrong tip
"horns"
Thick skin on work	Material too viscous
	Application too heavy
Coating fails to	Material too viscous
close & smooth over
Spray pattern irregular,	Orifice clogged
deflected	Tip damaged
Craters or pock marks	Solvent balance
Bubbles on work	Contamination or dust
Clogged screens	Extraneous material
	in paint.
	Coarse pigments
	Poorly milled pigments
	(paint pigments glocculate
	cover screen. Incompatible
	paint mixture & thinners.
TEST THE PATTERN

CORRECTION

Increase the pressure

Reduce pressure for satisfactory pattern Use less thinner

Use smaller spray angle tip

Use larger spray angle tip. (If coverage is OK, try tip in same nozzle group)

Use next smaller tip

Reduce pressure

Use next larger tip

Change for new tip

Use tip with a smaller spray angle

Thin material

Reduce pressure and/or use smaller tip

Thin material

Clean carefully

Replace with new tip

Use 1-3% "short" solvents remainder "long" solvents. (This is most likely to happen with material of low viscosity, lacquers etc.)

Clean surface to be sprayed

Clean screen

Use coarse screen if orifice size allows

Use coarser screen, larger orifice tips. Obain ball milled paint. If thinner was added, test to see if a

drop on top of paint mixes or flattens out on on the surface. If not, try different thinner in fresh batch of paint.

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