Adjusting The Spray Pattern - 3M Graco 50261 Manuel D'instructions

Adjusting the Spray Pattern

Follow these steps to establish the
1. Turn the fluid adjustment knob (21) counter clockwise until no
restriction of the trigger movement is felt, then turn out another
half turn. When the knob is turned far enough, the trigger should
be able to touch the gun handle when the gun is triggered.
WARNING
PRESSURIZED EQUIPMENT HAZARD
To avoid injury, never open the fluid adjustment knob (21) beyond the
one half turn indicated in Adjusting the Spray Pattern. If the
band or undercut on the knob stem (21) is visible, the knob is not
adjusted correctly and could result in serious injury. Repeat steps in
Adjusting the Spray Pattern.
Fig. 10
2. Turn the pattern adjustment valve (25) fully counter clockwise to
achieve the widest fan pattern.
Close
(narrower
pattern)
Fig. 11
3. Adjust the air supply regulator (F) to about 100 psi.
Fig. 12
Setup
correct fluid flow and air flow:
red
21
Open
(wider
pattern)
4. Trigger the gun and adjust the gun inlet pressure, turning the
needle valve at the gun air inlet:
HVLP, Compliant 200 kPa, 2.0 bar (29 psi)
Air Spray 345 kPa, 3.4 bar (50 psi)
5. Spray a test pattern to evaluate fluid flow and atomization.
6. To reach the desired pattern width, fluid flow rate, and finish,
make the following adjustments:
• For a narrower pattern (25), turn the pattern adjustment
valve clockwise.
• To reduce the fluid flow, turn the fluid adjustment valve (21)
clockwise to limit the trigger travel or replace the nozzle with a
smaller orifice.
• To improve atomization, reduce the fluid flow rate. Increasing the
air pressure can improve atomization but may result in poor
Transfer Efficiency (TE) or non-compliant operation.
7. For HVLP only, to measure the aircap atomizing pressures, use
the accessory aircap verification kit.
NOTES:
• If the fluid adjustment knob is turned clockwise all the way the gun
will emit only air.
• For maximum transfer efficiency, always use the lowest air setting
needed to achieve the desired finish.
• If available, use the fluid manufacturer's recommendations for this
gun model to set the air line pressure.
• For Compliant guns, to maintain compliant operation
(TE equal to HVLP) the gun inlet pressure must not exceed
200 kPa, 2.0 bar (29 psi).
• For HVLP guns, at 200 kPa, 2.0 bar (29 psi) gun inlet air
the pressure at the aircap will be 70 kpa, 0.7 bar (10 psi).
• For HVLP guns, local laws may limit the maximum automatic air
pressure to 70 kPa, 0.7 bar (10 psi) at the air cap for HVLP
compliance. The accessory Air Cap Verification Kit 50280 is
available to measure the atomizing pressure at the air cap.
5
pressure,