Spraying
12. Open gun fluid inlet valves A and B.
Note
On impingement guns, never open
fluid manifold valves or trigger gun if
pressures are imbalanced.
13. Disengage gun piston safety lock.
14. Test spray onto cardboard. Adjust pressure and
temperature to get desired results.
15. Equipment is ready to spray.
Spray Adjustments
Flow rate, atomization, and amount of overspray are
affected by four variables.
•Fluid pressure setting. Toolittlepressureresults
in an uneven pattern, coarse droplet size, low
flow, and poor mixing. Too much pressure results
in excessive overspray, high flow rates, difficult
control, and excessive wear.
•Fluid temperature. Similareffectstofluidpressure
setting. The A and Btemperatures can be offset to
help balancethefluidpressure.
•Mixchambersize. Choiceof mix chamber is based
on desired flow rate and fluid viscosity.
•Clean-off air adjustment. Too little clean-off air
results in droplets building up onthe front of the
nozzle, and no pattern containment to control
overspray. Too much clean-off air res ults in
air-assisted atomization and excessive overspray.
62 3A1705J