DeVilbiss FLG3, Service Bulletin, Page: 1 / 8

SERVICE BULLETIN
SB-2-630
Gun Repair Kit FLG-488
IMPORTANT: Before using this equipment, read all safety
precautions on page 2 and instructions. Keep for future use.
DESCRIPTION
These guns are light weight, general purpose suction feed spray
guns for conventional spraying applications suitable for use with a
wide variety of common coating materials. They come complete
with 1-quart metal suction cups.
The No. 1 (conventional) air cap requires a 10 CFM air supply at the
gun inlet of approximately 40 psi, measured with the trigger pulled.
Halogenated hydrocarbon solvents - for example; 1, 1, 1-
trichloroethane and methylene chloride - can chemically
react with the aluminum in this gun and cause an explo-
sion hazard. Read the label or data sheet for the material
you intend to spray. Do not use spray materials contain-
ing 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.
ASSEMBLY OF CUP TO GUN
1. Position yoke at right angle to gun body with vent hole in lid
toward rear and lever of cam toward front of gun.
2. Fasten cup lid assembly to gun by attaching nut, see
Figure 5, to fluid inlet nipple on gun. Tighten nut with
wrench only until snug.
INSTALLATION
Note
Protective coating and rust inhibitors have been used to
keep the gun in good condition prior to shipment. Before
using the gun, flush it with solvents so that these materi-
als will be removed from fluid passages.
For maximum transfer efficiency, do not use more pressure than is
necessary to atomize the material being applied.
Connect the gun to a clean, moisture and oil free air supply using
a hose size of at least
5/16" I.D. hose. Do not use 1/4" I.D. hose.
(25' x 1/4" hose at 18 CFM has a pressure loss of 25 psi. 25' x 5/16"
hose at 18 CFM has a pressure loss of 8 psi.)
FLG3 SUCTION FEED SPRAY GUNS
Note
If quick connects are required, use only high flow quick
connects such as DeVilbiss HC-4419 and HC-4719. Other
types will not flow enough air for proper gun operation.
Note
If an air adjusting valve is used at the gun inlet, use
DeVilbiss Model HAV-500 or HAV-501. Some competi-
tive adjusting valves have significant pressure drop
that can adversely affect spray performance. Models
HAV-500 and HAV-501 have minimal pressure drop.
OPERATION
Mix, prepare and strain the material to be sprayed according
to the paint maufacturer's instructions.
Strain material through a 60 or 90 mesh screen before pouring
into cup.
Engage pins on cup into yoke and tighten yoke bu moving lever of
cam clockwise.
PAINTING
Open the spreader adjustment valve (7) (Fan) by turning the valve
stem counterclockwise.
Close the fluid needle adjusting knob (13) by turning clockwise.
Turn on air supply and set gun inlet pressure to 40 psi for
conventional use. Some materials can be sprayed at lower
pressures, improving transfer efficiency.
Spray a test area. Turn the fluid needle adjusting knob (13)
counterclockwise until a full coat is obtained.
If the finish is too sandy and dry, the material flow may be too
low for the atomization air pressure being used. Turn the fluid
needle adjusting knob (13) counterclockwise to increase fluid flow.
If the finish sags, there is too much material flowing for the
atomization air pressure being used. Turn the fluid needle adjusting
knob (13) clockwise to decrease fluid flow.
Pattern width can be altered by turning spreader adjustment
valve (7), either clockwise to decrease the width or counterclock-
wise to increase the width.
Adjust inlet air pressure to provide a uniform dispersion of
atomized paint throughout the pattern. Keep air pressure as low
as possible to minimize bounce-back and overspray. Excessive
pressure will result in split spray patterns. Inadequate pressures
will cause heavy centered patterns and poor atomization.