DUTLESS BLASTING DB150, User Manual

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For example, if you are stripping a car to be repainted, you'll probably want to leave an anchor profile for the new paint
to adhere to. If you are simply cleaning calcium deposits from a pool — which will not be repainted — leaving a profile is
unnecessary.
ABRASIVE SIZE
Most abrasive is measured with mesh size. During production, it gets
shaken through various screens. These screens might have as little as 20
holes per square inch, or as many as 100. This means that 40/70 glass fits
through the 40–70 holes per square inch screens. 20/40 glass is coarser
than 40/70, and 60/100 glass is finer.
An anchor profile is a fancy way of describing the rough surface
created during the blasting process. These peaks and valleys are
usually measured in mils (1/1000 of an inch). One of the main causes
of premature coating failure is an insufficient anchor profile. It’s a good
idea to understand from the customer what he/she expects when you
are done. Some people prefer an anchor profile, while others will want a
smoother surface.
WHAT IS ABRASIVE?
Abrasive (also called media) is mixed with water inside the blast tank. When blasting, you propel this mixture towards a
surface at high speed, to remove paint, rust, and other coatings.
TYPES OF ABRASIVE
Dustless Blasting
®
allows you to use a wide variety of abrasives, either wet or dry. For wet blasting, any abrasive that sinks
in water and is not water soluble can be used. However, abrasives that are dirty or have a very inconsistent particle size
can cause problems, such as sputtering or clogging of the machine.
We largely recommend crushed recycled bottle glass, because it's clean, inexpensive, environmentally friendly, and suited
for a wide variety of jobs. Sometimes different abrasives are available simply based on geography.
A common question we get is "Can I use play sand?" The answer is NO. Play sand is not an industrial product, so it's not
controlled and graded the way abrasives are. It won't behave predictably in your equipment, and you could wind up in
loads of legal trouble, from the EPA to local municipalities. Most bags of play sand are explicitly marked "Not to be used
for sandblasting".
ABRASIVE SHAPE
Basically, there are two different shapes: angular which has sharp edges, and round with no edges.
Angular abrasive has sharp edges which will cut into the substrate, leaving an anchor profile for the new finish to stick to.
Examples of angular shaped media would be crushed glass, slags and garnet abrasives to name a few.
Round media is used mainly for cleaning or stripping while leaving the surface smooth. It will not rough up the surface or
leave an anchor profile. Examples of round media would be glass beads, sugar sand and plastic pellets.
Looks Like
20/40
40/70
60/100
ANGULAR ROUND
Choosing Abrasive