DeVilbiss PRI-601G Service Bulletin

IMPORTANT: Before using this equipment,
read all safety precautions and instructions.
Keep for future use.
DESCRIPTION
The complaint high volume low pressure
gravity feed PRI ® Primer gun is designed to
apply a wide variety of priming materials.
This gun was manufactured to provide a
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
air cap pressure at 30 psi gun inlet pressure.
An air cap test kit is available (see Accesso-
ries) which can be utilized to set the exact air
cap presssure. Air consumption for the PRI-
601G (# Primer 101 cap) is 16 SCFM at 10 psi
air cap pressure.
NOTE
This gun includes 300 series
stainless steel fluid tip and
needle. Fluid passageway is
anodized aluminum.Gun may be
used with chlorinated solvent
materials only if the attached
gravity cup is Delrin or Nylon.
Do not use aluminum cups with
chlorinated solvent materials.
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.
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).
PRI-601G HIGH VOLUME LOW PRESSURE
GRAVITY FEED PRIMER GUN
Depending on hose length, larger
I.D. hose may be required. Install an
HAV-501 air gauge at the gun handle
and air cap test kit over tip. When
gun is triggered on, adjust regulated
pressure to desired setting to pro-
vide a maximum of 10 psi at the air
cap. Do not use more pressure than
is necessary to atomize the material
being applied. Excess pressure will
create additional overspray and
reduce transfer efficiency.
If quick connects are required, use
only high flow quick connects
approved for HVLP use such as
DeVilbiss HC-4419 and HC-4719.
Other types will not flow enough air
for proper gun operation.
If an air adjusting valve is used at the
gun inlet, use DeVilbiss Model HAV-
500 or HAV-501. Some competitive
adjusting valves have significant
pressure drop that can adversely
affect spray performance. Models
HAV-500
minimal pressure drop, which is
important for HVLP spraying.
2 . Attach the gravity feed cup to the
material inlet.
Protective coating and rust inhibi-
tors have been used to keep the
gun in good condition prior to
shipment. Before using the gun,
flush it with solvents so that these
materials will be removed from
fluid passages.
OPERATION
Mix, prepare and strain the material to be
sprayed according to the paint maufacturer's
instructions.
NOTE
NOTE
NOTE
and HAV-501 have
NOTE
SERVICE BULLETIN
SB-2-200-D
Replaces SB-2-200-C
Repair Kit KK-5058-2
Strain material through a 60 or 90 mesh
screen.
1. Fill the gravity feed cup with the
material. Do not overfill. 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. Close the fluid needle adjusting screw
(17) by turning clockwise.
4. Turn on air supply and set gun inlet
pressure to lowest recommended pres-
sure for material being sprayed. Best
atomization will occur with 10 psig air
cap pressure. However, some materi-
als can be sprayed at lower pressures,
improving transfer efficiency.
5. Spray a test area by turning fluid
needle adjusting
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.
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 adjust-
ment valve (10), either clockwise to de-
crease the width or counterclockwise to
increase the width.
See Spray Gun Guide, SB-2-001 latest
revision, for details concerning setup of
spray gun.
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 pre-
vent scratching or burring of the holes
which will cause a distorted spray pattern.
screw (17)