DeVilbiss PLUS SB-2-475-F Service Bulletin

TM
PLUS HIGH EFFICIENCY SPRAY GUN (SUCTION/PRESSURE)
IMPORTANT: Before using this equipment,
read all safety precautions and instructions.
Keep for future use.
DESCRIPTION
TM
The Plus spray gun is a general-purpose,
heavy-duty, high-production spray gun suit-
able for use with most types of materials.
It is available in one suction feed version or
in two pressure feed versions.
NOTE
These guns include 400 series
stainless steel fluid tips and
needles. Guns should not be
used with chlorinated solvent
materials. See page 2 for poten-
tial hazards.
Important: These guns may be used with
most common coating and finishing mate-
rials. They are designed for use with mildly
corrosive and non-abrasive materials. If used
with other high corrosive or abrasive mate-
rials, it must be expected that frequent and
thorough cleaning will be required and the
necessity for replacement of parts will be
increased.
INSTALLATION
For maximum transfer efficiency, do not
use more pressure than is necessary to
atomize the material being applied.
1 . 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).
NOTE
Depending on hose length, larger I.D.
hose may be required. Do not use
more pressure than is necessary to
atomize the material being applied.
Excess pressure will create addi-
tional overspray and reduce transfer
efficiency.
NOTE
If quick connects are required, use
only high flow quick connects ap-
proved for HVLP use such as DeVil-
biss 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-511. Some competitive
adjusting valves have significant
pressure drop that can adversely
affect spray performance. Models
HAV-500 and HAV-511 have minimal
pressure drop.
2. Attach the suction feed cup or
fluid hose to the material inlet.
NOTE
Protective coating and rust inhibi-
tors have been used to keep the
gun in good condition prior to ship-
ment. Before using the gun, flush it
with solvents so that these materi-
als will be removed from fluid pas-
sages.
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.
1. Fill the suction or pressure feed cup
with the material. Do not overfill.
If using a suction cup, make sure that
the cup lid vent hole is clear.
2. Open the spreader adjustment valve
(10) (Fan) by turning the valve stem
counterclockwise.
3. Open fluid adjusting screw (17) by turn-
ing counterclockwise.
4 . Turn on air supply and set gun inlet
pressure to 40 psi. Some materials can
be sprayed at lower pressures, improv-
ing transfer efficiency.
5. Turn on the supply air to the pressure
cup (if used).
6. Spray a test area.
If the finish is too sandy and dry, the mate-
rial flow may be too low for the atomization
air pressure being used.
If the finish sags, there is too much material
flowing for the atomization air pressure
being used.
Both of the above can be corrected by
increasing or decreasing the atomization
air pressure or the material flow. Pattern
width can be altered by turning spreader
adjustment valve (10), either clockwise to
decrease the width or counterclockwise to
increase the width.
SERVICE BULLETIN
SB-2-475-F
Replaces SB-2-475-E
Repair Kit KK-5058-2
See Spray Gun Guide, SB-2-001 latest revi-
sion, for details concerning setup of spray
guns.
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 tooth-
pick 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 from cup, 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 lubri-
cants and packings.
NOTE
When replacing the fluid tip or fluid
needle, replace both at the same
time. Using worn parts can cause
fluid leakage. See Chart 2. Also,
replace the needle packing at this
time. Lightly lubricate the threads
of the fluid tip before reassem-
bling. Torque to 15-20 ft.-lbs. Do
not overtighten the fluid tip.
To prevent damage to fluid tip (5)
or fluid needle (11), be sure to
either 1) pull the trigger and hold
while tightening or loosening the
fluid tip, or 2) remove fluid needle
adjusting screw (17) to relieve
spring pressure against needle
collar.
TRANSFER EFFICIENCY
The DeVilbiss PLUS TM suction feed
and pressure feed spray guns,
when tested under recommended
conditions with automotive
refinishing materials, have been
found to exceed 65% transfer
efficiency.