What Blast Media Should I Use In A Wet Blast Cabinet?

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What Blast Media Should I Use In A Wet Blast
Cabinet?
www.quantumblast.com.au
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Choosing the correct abrasive media for wet
blasting is very important because an
inappropriate media choice will not provide the
desired finish. It can not only cause a rework
but in some cases may cause damage to the blasted
surface. The factors you have to consider when
selecting an abrasive media for wet blasting are
the grit size, shape, hardness, and density of
the media, and blasting velocity. Factors like
friability (tendency to break into smaller
particles under force), recyclability, and cost
are also important.
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• The different abrasive media that you normally
  use in a wet blast cabinet are garnet, glass
  bead, aluminum oxide, crushed glass, and soda
  bi-carbonate
• Garnet (Almandine and Alluvial) Garnet is a
  type of gemstone and has good natural abrasive
  properties. Garnet has a sub-angular shape, Mohs
  hardness number 7 to 7.5, comes in different grit
  sizes and it can remove coatings, old paint,
  rust, and mill scale from metal surfaces and can
  work on hard metals also. The coarser grit is
  suitable for working on aluminum, steel,
  stainless steel, and other metals and finer grit
  is suitable for materials like fiberglass. Garnet
  can quickly work through coatings and
  contaminants.

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• Crushed glass Crushed glass has Mohs number of
  5.5 to 7 and is good for wet blasting aluminum
  and steel. The crushed glass has an angular shape
  and forms a sharp anchor profile however,
  selecting a proper grit size and blasting
  velocity can give you the required anchor
  profile/finish. The advantage of crushed glass is
  it is a recycled material (environmentally
  friendly), cheap, and effective for many works.
  Crushed glass can be an economical media for the
  wet blasting of components like alloy wheels.
• Glass beads A glass bead media consists of
  spherical glass particles and leaves a fine and
  polished finish on the blasted surface. The Mohs
  hardness of glass beads ranges from 5.5 to 6 and
  the particle size can be coarse to fine.The glass
  beads have a smooth surface all over and are safe
  for blasting soft and delicate materials. Glass
  beads are very popular for wet blast cabinets and
  by varying the blasting velocity a smooth
  anchored profile or a fine finish can be achieved.

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• Aluminum oxide The aluminum oxide has angular
  shaped particles a Mohs hardness of 8 to 9 and
  the grit size of this media can be coarse to fine
  depending on the need. By varying the grit size
  and blasting velocity, aluminum oxide can be used
  for wet blasting hard metals (even with thin
  sections) and this is a good media for tough
  cleaning, extracting paint, coating, and rust.
  This is useful for finishing and edge rounding of
  surfaces. The high recyclability of aluminum
  oxide makes it an affordable media.
• Soda bi-carbonate The soda bi-carbonate used for
  wet blasting is not the baking soda used in our
  kitchen. There are companies like Armex and
  Natrium that manufacture a variety of soda
  bi-carbonates specifically for the soda blasting
  process. The size of soda bi-carbonate particles
  may vary from 70 to 270 microns. Soda
  bi-carbonate is not an abrasive material and
  hence it cannot be used for surface profiling.
  Soda bi-carbonate is used as a media when the
  surface needs a smooth finish without any profile.

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Selecting the correct abrasive media for a wet
blast cabinet is important and it is worth
spending some time on this. Noting down the
component details, surface condition, abrasive
media used, and the finish achieved and building
up practical data will help when similar jobs
come up again. For more information on wet blast
cabinets please visit Quantum Blast Phone
1300822569 E-Mail sales_at_quantumblast.com.au
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Contact Us
1300 822 569
sales_at_quantumblast.com.au
www.quantumblast.com.au