Preventive Maintenance; Operation - DeVilbiss FLG4 Service Bulletin

IMPORTANT: Before using this equipment, read all safety
precautions on page 2 and instructions. Keep for future use.
Halogenated hydrocarbon solvents - for example; 1, 1,
1- trichloroethane and methylene chloride - can chemi-
cally react with the aluminum in this gun and cause an
explosion hazard. Read the label or data sheet for the
material you intend to spray. Do not use spray materials
containing these solvents with this spray gun.
IMPORTANT: This gun may be used with most common coating
and finishing materials. It is designed for use with mildly corrosive
and non-abrasive materials. If used with other high corrosive or
abrasive materials, it must be expected that frequent and thor-
ough cleaning will be required and the necessity for replacement
of parts will be increased.

OPERATION

Strain material thru 60 or 90 mesh screen.
HVLP Models:
The No. 4 (HVLP) air cap requires an air supply at the gun inlet of
26 psi max., measured with the trigger pulled.
This gun was manufactured to provide maximum transfer efficiency
by limiting air cap pressure to 10 psi (complies with rules issued
by SCAQMD and other air quality authorities).
This gun will produce approximately 10 psi cap pressure at 26 psi
inlet pressure, as measured at the gun inlet.
Adjust fluid pressure to deliver the desired paint volume. Adjust
air pressure and fluid flow to provide a uniform dispersion of at-
omized paint throughout the pattern. Keep air pressure as low as
possible to minimize bounce - back and overspray. Excessive air
pressure will result in split patterns. Low air pressure will result in
heavy centered patterns and poor atomization. Excessive fluid flow
will result in heavy center spray patterns. Inadequate fluid flows
may cause the pattern to split. See "TROUBLESHOOTING" section.
Chart 1 – Fluid Tips
Fluid Tip (Ref. No. 5)
Part No. Computer No.
FLG-332-13K 803051
FLG-332-15K 803052
FLG-332-18K 803053
FLG-332-22K 803054
Chart 2 – HVLP Air Flows (#4 Cap)
Inlet Pressure Air Flow
(PSI) (SCFM)
17 11.5
21 13
26 15

PREVENTIVE MAINTENANCE

To clean air cap and fluid tip, brush exterior with a stiff bristle brush.
If necessary to clean cap holes, use a broom straw or toothpick if
possible. If a wire or hard instrument is used, extreme care must
be used to prevent scratching or burring of the holes which will
cause a distorted spray pattern.
To clean fluid passages, remove excess material at source, then
flush with a suitable solvent. Wipe gun exterior with a solvent
dampened cloth. Never completely immerse in solvent as this
is detrimental to the lubricants and packings.
Spray Gun Lubrication
Daily, apply a drop of SSL-10 spray gun lube at trigger bearing
stud and the stem of the air valve. The shank of the fluid needle
where it enters the packing nut should also be oiled. The fluid
needle packing (8) should be kept soft and pliable by periodic
lubrication. Make sure the baffle (5) and retaining ring (1) threads
are clean and free of foreign matter. Before assembling retaining
ring to baffle, clean the threads thoroughly, then add two drops
of SSL-10 spray gun lube to threads. The fluid needle spring (7)
and air valve spring (9) should be coated with a very light grease,
making sure that any excess grease will not clog the air passages.
For best results, lubricate daily.
Fluid Tip Fluid Tip
Size Size Applications
(in.) (mm)
0.051 1.3 General purpose, light to medium viscosity material.
0.059 1.5
0.070 1.8 Latex or heavy bodied materials.
0.086 2.2
Cap Presure
(PSI)
6
8
10
Note
When replacing the fluid tip or fluid needle, replace both at
the same time. Using worn parts can cause fluid leakage.
To prevent damage to the fluid tip (3) or fluid needle (8),
be sure to either:
• Pull the trigger and hold while tightening or loosening
the fluid tip, or
• Remove fluid needle adjusting knob (7) to relieve spring
pressure against needle collar.
SB-2-784-A Page 3