Graco EcoQuip 300 Operation, Repair, And Parts page 19

Abrasive Abrasive Metering Abrasive Metering Valve Metering Valve Settings Valve
There is no fixed formula for what works best in each application. The information below works best for the
majority of the time. From this initial setting, adjustments can be made up or down to get the fastest removal
rates without damage to the surface.
Normal settings are: 110 psi (7.5 Bar, 0.75 MPa) initial pot setting, less than 1/2 turn open metering valve,
blasting pressure at 80 psi (5.5 Bar, 0.55 MPa). For applications requiring higher performance, use
high-performance abrasive (the heaviest mass @ 80 grit) such as Garnet, and the highest pressures the
compressor can support. The initial pot pressure should always be 30 psi (2.0 Bar, 0.2 MPa) above the
intended blast pressure.
Gradually make adjustments to meet the specific requirements for each application. Higher blast pressures
will require turning the abrasive metering valve slightly more open (and vice versa). Make the adjustments
(see DataTrak Controls, page 9
rate while using the least amount of abrasive). Blasting pressures can range between 30 - 120 psi max
(2.0 Bar, 0.2 MPa – 8.2 Bar, 0.82 MPa).
Unlike conventional sandblasting, higher pressures do not necessarily mean better cleaning. Nozzle distance
and the angle to the surface has an effect on performance, as does the blast pressure. Choice of abrasive
also has a great effect. High-performance abrasive produces the best performance and can save enough
time to make up the difference in cost.
NOTE: Blasting with 150+ feet of blast hose requires the use of an electric blast control.
NOTE: NOTE:
Grit Size Grit Grit
General General General 40/70 crushed
glass
Wood
Wood Wood 80 (using a low
mass abrasive
like crushed glass
or walnut)
Steel
Steel Steel 60–80 (using
a high-mass
abrasive like
Garnet)
Fiberglass Fiberglass Fiberglass 40-70 low mass
NOTE: NOTE: Adjustment in blast pressure requires an NOTE:
adjustment of the abrasive metering valve
334667G
Settings Settings
) to achieve 7-10 cycles per minute to be the most efficient (cut at the fastest
Blast Pressure Pressure
Size Size Blast Blast Pressure
60-80 psi (4.1 Bar,
0.41 MPa- 5.5 Bar,
0.55 MPa)
40-50 psi (2.7 Bar,
0.27 MPa- 3.4 Bar,
0.34 MPa)
100-120 psi (6.8 Bar,
0.68 MPa- 8.2 Bar,
0.82 MPa)
45-65 psi (3.1 Bar,
0.31 MPa- 4.4 Bar,
0.44 MPa)
Abrasive Dose Dose Blast Angle
Abrasive Abrasive Dose Blast Blast
10 cycles per 35° - 65°
minute
8 cycles per 15° - 30°
minute
10–12 cycles per
65° - 85˚
minute
8 cycles per
35° - 45˚
minute
Operation
Angle Notes
Angle Notes Notes
None
Do not wash, as it
may raise the wood
grain. Brush off
excess abrasive after
the wood dries.
None
None
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