STEP 10 – Controlling the abrasive media flow
The pressure-pot is fitted with an abrasive metering valve (no. 5) located
on the bottom of the vessel. To adjust the valve, align the valve lever
perpendicular to the valve body (closed position). Now turn the lever
down approximately 30 degrees. This should be a good position to begin
adjusting the media flow. Slide your arms into the gloves in the arm ports
of the cabinet, grip the blast hose firmly, and depress the foot pedal to
begin blasting (it is normal when starting to blast that one or two spurts of
abrasives come out of the nozzle before uniform blasting begins). Best
blasting is achieved when the abrasive can barely be seen as a mist in the
air/media stream from the nozzle. Too much abrasive in the flow will
reduce the ability of the system to blast effectively and will cause surging.
Too little abrasive flow will slow your blasting and yield poor results.
Opening the abrasive metering valve will put more media into the mix
while closing it will deliver more air and less abrasive. Once the metering
valve is properly set, it will require only occasional maintenance.
STEP 11 – Blasting
Best results are achieved by sandblasting between 20 and 80 psi and
holding the nozzle at a 90 degree angle to the surface at about 4 to 8 inches
away. Maintain a continuous, even movement of the nozzle to prevent the
media from cutting too deep into your work surface.
NOTE: IF USING GLASS BEAD KEEP PRESSURE BELOW 40
PSI. GLASS BEAD SHATTERS INTO DUST ON CONTACT WITH
ITS TARGET AT PRESSURES OF 40 PSI AND ABOVE
.
To stop blasting, release the foot pedal and the air media valve will shut
itself off automatically. To begin again, just press down on the foot pedal
.
To shut down the system, simply close the air inlet ball valve (no. 3)
and press down on the foot pedal. The pressure relief valve (no. 12)
can be activated by pulling on the ring, however, depressing the foot
pedal is easier and can be accelerated by pulling on the pressure relief
valve simultaneously.
