Graco 254986 - Spray Techniques

Spray Techniques
311764D 11
Spray Techniques
Recommended Nozzle Selection Chart
1
Control air volume with gun air valve.
2
For more material volume try a larger nozzle.
Adjusting the System
Sufficient fluid output (volume and pressure) and good
atomization is a balance of atomozing air, material thick-
ness/material flow and nozzle selection. Achieving the
correct balance for your application requires experimen-
tation to achieve desired results. Keep in mind these
important points when adjusting gun:
• Select proper nozzle for your application. See Noz-
zle Selection Chart. Remember, the larger the noz-
zle, the heavier the pattern.
• Start sprayer with gun air flow valve completely
open. If needed, slowly close gun air flow until you
get a good spray pattern. Use minimum amount of
air at spray gun to achieve proper spray pattern and
to minimize bounce back.
+ Test spray pattern on cardboard. Hold gun 18 to
24 in. (45.7 to 60.9 cm) from surface. Use this
spraying distance for most applications.
• Air and material flow adjustments can be made at
the gun on all units. TX 125 units have a material
flow control knob (G).
+ Opening air valve increases air flow through gun,
which decreases texture material flow through
pump.
+ Closing air valve decreases air flow through gun,
which increases texture material flow through pump.
To Get Less Material
Try one or a combination of these methods:
• Open air valve.
• Turn gun flow adjustment nut to decrease flow,
counter-clockwise.
• Use smaller nozzle.
To Get More Material
Try any one or a combination of these methods:
• Close air valve.
• Turn gun flow adjustment nut to increase flow, clock-
wise.
• Use thinner material mixture.
• Use a larger nozzle.
Preventing Material Surge at Gun Trigger
Pressure will build up in the system when you stop trig-
gering the gun. To prevent material surge at initial gun
triggering:
• Point gun away from surface you are spraying when
you first pull trigger.
• When you first start to spray, hold the gun away from
the surface and gradually work your way closer to it.
• Keep gun moving.
• After you begin spraying, trigger the gun as little as
possible.
For Continuous Spraying
Use trigger lock to hold trigger open and reduce fatigue.
Check Material Consistency Periodically
Check and thin material as needed to maintain proper
consistency. The material may thicken as it sits and slow
down production. Agitate periodically.
Application
Nozzle Size
2
Air Volume
1
Simulated
Acoustic
6 mm, white (fine to medium)
8 mm, gray (coarse)
medium to
high
Orange peel
4 mm, beige,
6 mm, white
medium to
high
Splatter
coat
6 mm, white
8 mm, gray
low to
medium
Knockdown
8 mm, gray
12 mm, black
low