DUTLESS BLASTING DB150, User Manual

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10
BLAST PRESSURE
Different materials and coatings call for different pressures or blasting distances. Thick metal can handle a lot of
pressure, while sheet metal could be dented by using too much pressure. Simple paint may come off nicely with the
nozzle far away, while tough undercoating may come off better with the nozzle closer.
The distance you hold the blast nozzle from the material affects the harshness and speed of the blast and changes the
"blast pattern" size. If you hold the nozzle too far away, the blast pattern will be big, but the coating will come off too
slowly. If you hold the nozzle too close, the coating will come off quickly, but the blast pattern will be small. With a tiny
blast pattern you'll have to move your arms a lot more to cover some area, which is inefficient. The best things is to find a
nice balance between blast pattern size and removal speed.
ADJUSTING BLAST PRESSURE
The Dustless Blasting
®
system allows you to easily change the blast pressure by turning one simple knob. The higher the
pressure is, the higher your productivity. Obviously lower pressures are more gentle on whatever substrate you're blasting.
If you need to blast on softer material or very thin metal, lowering the pressure is a good idea to prevent damage.
A clockwise rotation of the pressure regulator knob will increase the pressure, while a counter clockwise rotation will
lower pressure. If you try to lower the pressure while the blast tank is pressurized, you'll need to either have someone blast
simultaneously, or just open the blowdown valve slightly to release some of that pressure.
COMMON GUIDELINES
Marine
On thick steel like ship hulls, you can operate at about 150 PSI. Fiberglass requires a lower pressure — about 70 PSI —
with a larger standoff distance.
Automotive
For most automotive uses, 120 PSI is ideal. Find a balance between blast pattern size, and speed.
For thick aluminum like a large trailer, you can blast at up to 150 PSI.
Graffiti Removal
For removing graffiti from a brick wall, use about 100 PSI so you don't etch the brick. The graffiti will still come off quickly
at this low pressure.
Here is a chart of some suggested blast pressures:
*The closer the nozzle is to the blast surface, the smaller the blast pattern.
Fiberglass
Boats
Blast Pressure
Blast Distance
Blast Pattern
70 PSI
18-24 in.
Large
Metal
(Auto)
100-120 PSI
12-14 in.
Medium
Aluminum
120-150 PSI
12-20 in.
Medium-Large
Steel
150 PSI
10-14 in.
Medium
Brick
100 PSI
18-24 in.
Large
Choosing Blast Pressure