MicroBlaster MB1005
Section 3: Using the MicroBlaster
Comco Inc.
3-11
Issue Date: September 2003
Air Pressure
The simplest method of changing cutting speed is to vary the air pressure to the tank
with the “Air Pressure” adjustment knob. Increasing the pressure increases the velocity
of the abrasive particles. Therefore, the higher the pressure, the faster the work surface
will be abraded. It should be mentioned that the nozzle, hose, and fittings might also
wear at a faster rate under higher pressure conditions.
CAUTION:
MAXIMUM BLAST SETTING ON YOUR BLASTER
Never operate any micro-abrasive blaster with the air pressure
regulator turned fully open. Check your compressor settings to
determine the air pressure level it uses to trigger the re-pressurize
cycle. The blast pressure setting on your blaster should always
be set at least 10psi below this point, which is the lowest supply
pressure coming from your compressor. If the inlet pressure
drops below the blast pressure setting, air and abrasive will cause
damage to your machine as it flows backwards through the
system.
Powder Flow Adjustment
Cutting speed and surface texture is affected by media concentration. The best
concentration can only be determined by testing each application. The abrasive flow
circuit from the tank inc
orporates a media concentration adjustment labeled “Powder
Flow” on the front panel (see Figure 3-4). This adjustment controls the amount of clean,
abrasive-free air that is mixed with the outgoing abrasive airstream from the tank.
Turning the knob clockwise increases the media concentration. As the knob is turned
counterclockwise, from the “MAX” position, more and more clean air is added, reducing
the quantity of abrasive in the outgoing airstream. Begin with the knob in the “MAX”
position then gradually adjust the knob counterclockwise until the desired cutting rate is
achieved.
Bypass Orifice
For applications that use large nozzles and require very heavy abrasive flows, a bypass
orifice can be installed into the MicroBlaster tank bypass tube. The orifice threads into
the nylon bypass tube along the side of the tank.
If the tube is partially or completely plugged, the pressure differential across the tank
orifice is increased, thereby expanding powder flow. The bypass orifice, MB1021, is
available for this purpose. Powder flow will be increased 10-25% when the orifice is
screwed into the top of they bypass tube.
A significant increase in abrasive flow does not always increase the speed at which parts
can be processed. The micro-abrasive blasting process is optimized to work with less
abrasive, using air flow and particle velocity to improve efficiency. Please contact
Comco's Technical Support team for assistance in fine-tuning your abrasive blasting
process.
Rev. 9/12
