Cyclone Sand Blaster: Difference between revisions

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[[Category:Tools]]
[[Category:Tools]]


Link to: [[:Category:Metal Shop | Metal Shop main page]]
Link to: [[:Category:Metal Shop | Metal Shop main page]]


Link to:  [[:Category:Metal Shop#Tools | Metal Shop tool list]]
This tool is used in [[:Brackets_Tutorial_3:_No_Frills_Shelf_Bracket#Cleaning | Brackets tutorial 3.]]


{{ToolBox
{{ToolBox
Line 8: Line 11:
   |tool_subtitle      = Cyclone Manufacturing
   |tool_subtitle      = Cyclone Manufacturing
   |image              = Metal_shop_sandblaster_action_shot.jpg
   |image              = Metal_shop_sandblaster_action_shot.jpg
   |caption            = A Happy Blaster
   |caption            = A happy blaster
   |make              = Cyclone Manufacturing  
   |make              = Cyclone Manufacturing  
   |model              = DW-7335
   |model              = DW-7335 (obsolete)
   |serial            = Unknown
   |serial            = Unknown
   |manufacturer_specs =   
   |manufacturer_specs =   
   |manual            =  
   |manual            = [[media:Cyclone-Manual-FT-6035-5532.pdf | Manual for a similar model]]
   |location          = Metal Shop
   |location          = Metal Shop
   |rubric            =  
   |rubric            =  
   |training          =[https://www.artisansasylum.com/class-catalog Tool classes]
   |training          =[https://www.artisansasylum.com/class-catalog Tool classes]
   |testing            = [https://www.artisansasylum.com/tool-testing Tool testing], or [[:Category:Metal Shop#Tool Testing  
   |testing            = [https://www.artisansasylum.com/tool-testing Tool testing] <span style="color:red">OR</span>  [[:Category:Metal Shop#Tool Testing Night|come to the shop on Tool Testing Night]]
Night|come to the shop on Tool Testing Night]]
   |restrictions      = RED
   |restrictions      = green
   |tool_categories    =  
   |tool_categories    =  
}}
}}


{| class="infobox" cellspacing="0" style="width: 2em; text-align: left; font-size: 125%; line-height: 1.5em;"
[[File:No lead warning.png|127x127px]][[File:Blaster dust hazard.png|127x127px]][[File:Goggle mask.png|149x149px]]
! colspan="2" class="infobox-image" | [[File:goggle_mask.png|120px| ]]
 
|-
| colspan="2" | 
|-
|}


{| class="infobox" cellspacing="0" style="width: 2em; text-align: left; font-size: 125%; line-height: 1.5em;"
! colspan="2" class="infobox-image" | [[File:_blaster_dust_hazard.png|180px| ]]
|-
| colspan="2" | 
|-
|}


{| class="infobox" cellspacing="0" style="width: 2em; text-align: left; font-size: 125%; line-height: 1.5em;"
{{EyeWarning}}
! colspan="2" class="infobox-image" | [[File:_no_lead_warning.png|180px| ]]
|-
| colspan="2" | 
|-
|}




{{EyeWarning}}


== Description ==
A sand blaster mixes abrasive grains with a jet of compressed air that's used to abrade the surface of a (usually metal) part. This cleans paint, rust, and other forms of dirt off the part; it also roughens the part's surface.  The blast gun is enclosed in a sealed steel cabinet.  The user manipulates the tool with thick rubber gloves that pass through the wall of the cabinet.


=Description=
The sand blaster cabinet is located in a small room within the metal shop on the south wall adjacent to the fenced-in outdoor porch.


A sand blaster is a machine that mixes abrasive grains with a jet of compressed air and allows the user to abrade the surface of a part, usually metal.  This results in a clean though roughened part free of paint, rust, and other forms of dirt.  For smaller parts the blast gun is contained in a glovebox cabinet sealed off from the outside.  The user manipulates the tool with thick rubber gloves that pass through the wall of the cabinet.
'''Sand blasting is the LAST stage, not the first, in cleaning a part and preparing the surface for finishing.'''


The sand blaster cabinet at Artisans Asylum is located in a small room within the Metal Shop on the south wall adjacent to the fenced-in outdoor porch.
''Do not use the sandblaster to clean heavily rusted pieces.'' This would be a slow, inefficient way to do that and is likely to clog and damage the equipment. After testing for lead, remove surface rust with wire brushes, manually or with a power tool attachment. Only then is the piece ready for sandblasting.


=Use For=
{{Warning|text="Sandblasting" is a misnomer. NEVER use actual sand in a blasting process.}}


== Use For ==
* Steel
* Steel
* Stainless Steel
* Stainless steel
* Zinc-coated steel (Galvanized)
* Zinc-coated (aka galvanized) steel
* Aluminum, Titanium, Brass
* Aluminum, titanium, brass
* Painted metal
* Painted metal (abrade with wire brush or sandpaper first)
* Lightly Rusted Parts
* Lightly rusted parts after initial cleaning
 
=Do Not Use For=


== Do Not Use For ==
* Lead-based paints
* Lead-based paints
* Asbestos
* Asbestos
* Greasy or Oily Parts
* Greasy or oily parts
* Massively Rusty Parts
* Massively rusty parts
{{Warning|text=Use a lead-test swab to verify that paint is NOT lead-based!}}{{Warning|text=If the sandblaster becomes contaminated with lead the media must be disposed as TOXIC WASTE and the cabinet must be thoroughly cleaned out!}}


'''Use a lead-test swab to verify that paint if NOT lead-based!'''
== Personal Safety ==
[[File:Goggle mask.png|right|186x186px]]
* '''NEVER use silica sand as an abrasive media.''' Always use media designated for blast use.


'''If the sandblaster becomes contaminated with lead the media must be disposed as [[TOXIC WASTE]] and the cabinet must be thoroughly cleaned out!'''
* '''Test paints and coatings for [[LEAD]] using the test swabs provided.''' The swabs change from yellow to red when lead is present.  If lead is detected do not clean with the sand blaster.


=Safety Notes=
* '''Wear safety goggles.'''  Eyeglasses don't protect against abrasive dust.


==Personal==
* Wear respirator or N95 or better mask when using the machine or working in the room when the machine is being usedAll fine dust is hazardous to breathe.
{| class="infobox" cellspacing="0" style="width: 2em; text-align: left; font-size: 125%; line-height: 1.5em;"
! colspan="2" class="infobox-image" | [[File:goggle_mask.png|80px| ]]
|-
| colspan="2" |  
|-
|}
* '''Wear safety goggles.''' Eyeglasses don't protect against abrasive dust.


*  Wear a dust mask or respirator when using the machine or working in the room when the machine is being used.  All dust is hazardous to breathe.
* Place the workpiece in the blast cabinet and close the hatch tightly to avoid dust escaping from the cabinet. Check that doors on both ends are latched close along with both hoppers.  When removing workpieces, some dust will unavoidably mix with the room air. Wear a dust mask at all times when working in sand blast room.


Glove-box gloves are at a fixed height above the floor.  If they are too high, a stand should be provided.  Use care when stepping on and off the stand.
Cabinet gloves and viewing window are at a fixed height above the floor.  If they are too high, a stand should be provided.  Use care on unstable stands.


*  If the blast gun is not properly grounded to the cabinet, static electricity can cause shocks to the operator.  If static shocks are encountered, check the ground connection to the gun.
*  If the blast gun is not properly grounded to the cabinet, static electricity can cause shocks to the operator.  If static shocks are encountered, check the ground connection to the gun.


* '''Do not use silica sand as an abrasive media.''' The preferred sand blasting media is [https://www.grainger.com/product/Blast-Media-Brown-Aluminum-6YY38 aluminum oxide.]
*  Use caution when lifting heavy parts into the sandblaster cabinet.
 
* Use caution when lifting heavy parts into the sandblaster cabinet.


*  If a part is too large to allow the hatch to close and seal, do not operate the sandblaster.
*  If a part is too large to allow the hatch to close and seal, do not operate the sandblaster.


*  Use caution with the foot pedal and hoses. They are a trip hazard.
*  Use caution with the foot pedal and hoses. Place them where the trigger cannot be accidentally depressed when the hoppers or cabinet are open.
 
==Machine==


* '''Test paints and coatings for [[LEAD]] using the test swabs provided.''' The swabs change from yellow to red when lead is present. If lead is detected do not clean with the sand blaster.
== Shop and Equipment Care ==
* '''EMPTY THE SAND BLASTER CABINET OF USED MEDIA AFTER EVERY USE.''' Sift used media into provided bucket matching the type of media you are using, and dispose of filtered waste in trash. Do not leave machine full of used media. Do not "top-off" with clean media in hoppers with used media. If media is too spent to use effectively, discard and start with fresh media. Mixing new media with partially spent media wastes media and makes an ineffective blast medium.


* Do not abrade greasy or oily parts in the sandblaster. These will case the media to clump and clog the flow lines.  If it happens, the media must be replaced.
* Shop standard media is [https://www.grainger.com/product/Blast-Media-Brown-Aluminum-6YY38 brown aluminum oxide]. If using alternate media, such as glass or ceramic beads, empty cabinet and ''thoroughly clean rails etc. inside the cabinet, both '''before and after''' using this media.''


* Place the workpiece in the blast cabinet and close the hatch tightly to avoid dust escaping from the cabinet.  When removing workpieces, some dust will unavoidably mix with the room air.  Wear a dust mask at all times.
* Do not abrade greasy or oily parts in the sandblaster.  These can cause the media to clump and clog the flow lines, and damage the equipment.


* Do not attempt to move the blast cabinet when it is full of abrasive media.
* Do not move the blast cabinet when it is full of abrasive media.


* Do not point the blast gun at the rubber gloves or the cabinet window or the cabinet ceiling light.
* Do not point the blast gun at the rubber gloves or the cabinet window or the cabinet ceiling light.


=How to Prepare Metal Workpieces for Blasting=
== How to Prepare Metal Workpieces for Blasting ==
 
{| class="wikitable"
'''*  TEST FOR LEAD.'''
|+
 
![[File:Metal shop lead test instructions.png|none|thumb|250x250px|Lead test swabs]]
{| class="infobox" cellspacing="5" style="width: 2em; text-align: left; font-size: 100%; line-height: 1.5em;"
![[File:Metal shop lead test swabs.png|thumb|250x250px|How to swab|none]]
! colspan="2" class="infobox-image" | [[File:Metal_shop_lead_test_YES.jpg|163px|Pb swab color yes lead]]
![[File:Metal shop lead test YES.jpg|thumb|250x250px|Color when lead is detected]]
|-
![[File:Metal shop lead test NO.jpg|thumb|250x250px|Color when no lead is detected]]
| colspan="2" | Color if lead is present
|-
|}
|}
{{Warning|text=If the machine becomes contaminated with lead, tell the facilities manager so that the media can be safely disposed. It is toxic waste. It is not legal to throw the media away yourself. The blast cabinet must be scrubbed to remove toxic dust.}}


{| class="infobox" cellspacing="5" style="width: 2em; text-align: left; font-size: 100%; line-height: 1.5em;"
# '''TEST FOR LEAD.''' Lead and lead paint are forbidden on this machine. Use a lead test swab to verify that there is no lead on the surface of your workpiece.
! colspan="2" class="infobox-image" | [[File:Metal_shop_lead_test_NO.jpg|127px|Pb swab color no lead]]
## Moisten the tip with water, wait 2 seconds for the reagent to dissolve, then rub the surface.
|-
## If no lead is present the swab stays yellow-orange.  It turns crimson if lead is present.
| colspan="2" | Color for no lead
# '''Clean off any massive rust with a grinder before placing the workpiece in the sandblaster.''' Large flakes of rust can mix with the blasting media and clog the flow lines leading to the gun.
|-
# '''Degrease the workpiece.''' If greasy or oily, clean the workpiece with a solvent or a water-base cleaner such as Simple Green.  Make sure it is dry before placing it in the blast cabinet.
|}


{| class="infobox" cellspacing="5" style="width: 2em; text-align: left; font-size: 100%; line-height: 1.5em;"
== Sandblaster Parts ==
! colspan="2" class="infobox-image" | [[File:Metal_shop_lead_test_swabs.png|120px|Pb swab instruction]]
[[File:Blaster with dust collector labeled.jpg|thumb|400x400px|The sandblaster and dust collector installation]]
|-
| colspan="2" | How to Swab
|-
|}


{| class="infobox" cellspacing="5" style="width: 2em; text-align: left; font-size: 100%; line-height: 1.5em;"
The sand blasting room has ventilation to the outside. Turn on the ventilation using the timer switch on the wall next to the CNC plasma cutter.
! colspan="2" class="infobox-image" | [[File:Metal_shop_lead_test_instructions.png|180px|Pb swabs]]
|-
| colspan="2" | Lead test swabs
|-
|}


Lead and lead paint are forbidden on this machine.  Use a lead test swab to verify that there is no lead on the surface of your workpiece.
The sandblaster has three free-standing components. The cabinet is the largest, and the other two are the components of the two-stage dust collector to the left of the cabinet.


Moisten the tip with water, wait 2 seconds for the reagent to dissolve, then rub the surface.   
The sandblaster has two bays.  Presently the RIGHT bay is the only one usedOur [[Antwerp_Shop_Air | compressed air service]] is only sufficient for operating one bay.


If no lead is present the swab stays yellow-orange.  It turns crimson if lead is present.
Turn on the dust collector (located in the back of the room) by plugging it and the air filter into the outlet on the left.


If the machine becomes contaminated with lead, tell the facilities manager so that the media can be safely disposed.  It is toxic waste.  It is not legal to throw the media away yourself.  The blast cabinet must be scrubbed to remove toxic dust.
Turn on the cabinet lights with the small switch on right hand box.


'''*  Clean off any massive rust with a grinder before placing the workpiece in the sandblaster.'''
The sandblasting action is controlled with the foot pedal on the floor or stand. Always stay aware of the placement of the foot pedal so it's not accidentally triggered.


Large flakes of rust can mix with the blasting media and clog the flow lines leading to the gun.
== Instructions For Use ==
[[File:Sandblaster vent switch.jpg|thumb|221x221px|The power switch for the sandblast room ventilator is located around the corner on the back wall adjacent to the CNC plasma cutter.]]
1.  Ensure that the [[Antwerp_Shop_Air | air compressor]] is on.  It is located in the closet in the loading dock area.  


'''*  Degrease the workpiece'''
2. '''Turn on the room ventilator.''' This switch is in the CNC Plasma area (see image on right).


If greasy or oily, clean the workpiece with a solvent or a water-base cleaner such as Simple Green.  Make sure it is dry before placing it in the blast cabinet.
3. '''Put on goggles and a dust mask or respirator.'''


=Parts of the Sandblaster=
4. Check the air pressure at the regulator on the blaster cabinet. Target pressure is 60 - 100psi.


{| class="infobox" cellspacing="5" style="width: 2em; text-align: left; font-size: 100%; line-height: 1.5em;"
5. Plug in the two-stage air filter at the end of sand blaster room, and cabinet if that's not already plugged in.  
! colspan="2" class="infobox-image" | [[File:blaster_with_dust_collector_labeled.jpg|600px|Bllaster labeled]]
|-
| colspan="2" | The Sandblaster and dust collector installation
|-
|}


The sandblaster has three free-standing components: The cabinet is the largest, and the others are a two-stage dust collector to the left of the cabinet.
6. Check that the media hoppers were emptied by the last user. If they were not, empty and sift the media before beginning.


Presently only the right-hand glovebox station is working.
7. Add media to the hopper where you intend to work, pouring it through the grate in the cabinet. The correct amount of media is between 10 and 20 lbs, depending on the media. Too much media will compact in the hopper can clog the feed hose.  Make sure the feed tube is down in the media.


Turn on the dust collector by plugging it in to the left.
{{Imbox|text=We use brown aluminum oxide for our standard media; use 3 - 5 quarts (yogurt container scoops). Glass bead media is also available for member use. Use ONLY media intended for blasting use - NEVER use actual, silica sand.}}


Turn on the overhead lights with the small switch on the right-hand box.
8. Place the workpiece in the cabinet and latch the hatch shut. Confirm that the doors on both ends of the cabinet are latched, as well as both hoppers.


The switching valve should be in the up-down position.
9.  Arrange the stand as/if needed and place the foot pedal in a convenient spot. Be careful of tippy step-stand.


Blast media is contained in the hoppers below each station.
10.  Turn on the cabinet light switch on top right of the cabinet. Optionally, also shut off room light for better visibility into the cabinet.  


The sandblasting action is controlled with the foot pedal on the floor on the right side of the cabinet.
11.  Stick hands into rubber gloves, grasp blasting gun and step on the foot pedal to '''BLAST!!!'''


The room has ventilation to the outside.  The switch is located on the wall next to the CNC plasma cutter.
* If no media appears to be coming out, and no abrasion is happening, check valve lever on front of cabinet.  


=Operation Notes=
* While the air is flowing, it may be necessary to wiggle the dip tube that reaches down into the hopper where the media is located.


{| class="infobox" cellspacing="5" style="width: 2em; text-align: left; font-size: 100%; line-height: 1.5em;"
* After a long period working, the media may migrate from the hopper in use to the hopper not in use. Simply place baker's tray under opposite hopper, open to collect media, close, and pour the tray back into the hopper in use. BE CAREFUL WHEN DOING THIS to stay always aware of the foot pedal location, so as not to accidentally trigger it while the cabinet is open.  
! colspan="2" class="infobox-image" | [[File:Sandblaster_vent_switch.jpg|200px|Ventilator switch]]
|-
| colspan="2" | The power switch for the sanblast room ventilator is located around the corner on the back wall adjacent to the CNC plasma cutter.
|-
|}


1Ensure that the air compressor is on.  It is located in a closet in the loading dock area.  
* Open the cabinet and inspect your work periodicallyGive the hatch a thump and wait a minute or two for the dust to settle before opening it.


2. '''Turn on the room ventilator.''' Switch located in the plasmatron corral.
12. When finished, place baker's tray under the hopper, empty the media out of the machine and carefully pour through the sifter back into the proper "in-use" bucket. Empty both hoppers as media will have migrated during use.  


3. '''Put on goggles and a dust mask or respirator.'''
13. Sweep loose media off the floor. Loose media is a respiratory hazard and can create a slip hazard. Remove used paper towel, gloves etc., from room; empty dust pan and waste from sieve into trash can in main metal shop.  


4. Place the workpiece in the cabinet and close the hatch tightly.
{{Imbox|text=If using any media other than the shop-standard aluminum oxide, you must thoroughly clean the cabinet when you are finished. Remove metal grates and use a broom to clean the rails inside the cabinet. When using shop standard media, emptying the hoppers and sifting is sufficient cabinet clean-up.}}


5. Arrange the stand as needed and place the foot pedal in a convenient spot.
{| class="wikitable"
|+
![[File:Blaster hopper drain 3.jpg|none|thumb|150x150px|Grasp the latch.]]
![[File:Blaster hopper drain 4.jpg|none|thumb|150x150px|Open the hatch, part way at first to begin opening, then fully to get all of the media out.]]
![[File:Sand blaster draining the hopper.png|none|thumb|150x150px|The total quantity of media in the hopper should be 10 - 20 lbs, or 3 - 5 quarts in volume of aluminum oxide media.]]
![[File:Sand blaster sifting the sand.png|none|thumb|173x173px|Pour the media through the screen provided to remove flakes.]]
![[File:Sandblaster sifted residue.jpg|none|thumb|150x150px|Flakes can block the gun and damage the hoses.]]
![[File:Blaster hopper drain 2.jpg|none|thumb|150x150px|Move the magnetic brace.]]
|}


6. '''Plug in the two-stage dust collector''' located to the left of the cabinet.
== Draining Media from the Hopper ==
Empty the media hoppers and sift the media after each use. Each user in this shared facility must have access to good, clean media, not media contaminated by rust and remnants from the previous user's project.  


7.  Turn on the overhead light.  Switch on top right of the cabinet.
Place the baker's tray under the hopper before opening it.


8. Step on the foot pedal and '''BLAST!!!'''
Sift media into the proper "In-Use" bucket.


* While the air is flowing, it may be necessary to wiggle the dip tube that reaches down into the hopper where the media is located.
The latches holding the hopper hatches closed are supported by a magnetic brace helping hold the latch in place. Slide the brace out of the way before opening the latch. Open part way to allow media to begin to flow, then open the rest of the way. Always replace magnetic braces to support the latch after closing.


*  If you experience static shocks, wear a ground strap or tie a ground wire from the gun to the grill inside the cabinet.
== Adding Media to the Hopper ==
Open the hatch on the side of the blast cabinet and pour the media into the hopper.


* Open the cabinet and inspect your work periodically.  Wait a minute or two for the dust to settle before opening the hatch.
== Troubleshooting ==
 
{| class="wikitable"
=How it Works=
|+
!PROBLEM
!CAUSE
!REMEDY
|-
| rowspan="3" |Excessive Dust
|Dust collection system malfunctioning
|Empty canister and replace or clean filter bag
|-
|Abrasive media worn out
|Replace media
|-
|Too much media in hopper
|Remove excess media
|-
| rowspan="2" |Uneven blasting action
|Too much media in hopper
|Remove excess media
|-
|Top of abrasive tube covered
|Move media away from top of pickup tube
|-
| rowspan="5" |Inadequate speed or efficiency of blast
|Media worn out
|Replace with new media
|-
|Worn blast gun parts or hoses
|Inspect/adjust/replace parts
|-
|Too much blast material
|Remove excess material, 10-15 pounds max
|-
|Too much air
|Regulate air to 70-90 PSI
|-
|Too little air
|Check shop air; make sure compressor is still on
|-
|Poor Blast Pattern
|Nozzle worn
|Replace nozzle
|-
| rowspan="3" |Static Electricity
|Dry environmental conditions
|Install static electricity band; Get lined gloves
|-
|Change in humidity
|Stand on cardboard/rubber mat;
Get lined gloves
|-
|Faulty ground wiring
|Check electrical wiring
|-
|Surging
|Too much media in hopper
|Remove excess media
|-
|Unit won’t blast
|Excessively worn blast gun parts
|Properly replace parts
|}


== How it Works ==
The sandblasting gun is a pneumatic device called a '''Venturi'''.  Compressed air is fed into the end of the gun and issues through the nozzle.  Inside the gun the air jet traverses a side entry that is connected to a dip tube that reaches into the pile of media in the hopper.
The sandblasting gun is a pneumatic device called a '''Venturi'''.  Compressed air is fed into the end of the gun and issues through the nozzle.  Inside the gun the air jet traverses a side entry that is connected to a dip tube that reaches into the pile of media in the hopper.


Line 235: Line 268:
|}
|}


The suction in the dip tube collects media from the hopper and feeds it into the air jet.
The suction in the dip tube collects media from the hopper and feeds it into the air jet. Aluminum oxide has a density almost double that of glass.  Excessive media in the hopper will cause it to compress in the lower portions and make it unflowable.
 
If there is too much media in the hopper it is necessary to agitate the dip tube to keep the media flowing up to the gun.  This can make the process seem like a three-handed job at times if you need to use a hand to steady the workpiece.
 
The user needs two hands and one foot to operate the machine. This leaves one foot to stand on. 


Aluminum oxide has a density almost double that of glass.  Excessive media in the hopper will cause it to compress in the lower portions and make it unflowable.  The correct amount of media for reliable operation is 1-2 quarts, about 10 lbs.
'''The correct amount of aluminum oxide media for reliable operation is about 1 gallon, roughly 15 lbs.'''
 
=Draining Media from the Hopper=
{| class="infobox" cellspacing="5" style="width: 2em; text-align: left; font-size: 100%; line-height: 1.5em;"
! colspan="2" class="infobox-image" | [[File:blaster_hopper_drain_4.jpg|200px|drain 4]]
|-
| colspan="2" | Open the hatch.
|-
|}
{| class="infobox" cellspacing="5" style="width: 2em; text-align: left; font-size: 100%; line-height: 1.5em;"
! colspan="2" class="infobox-image" | [[File:blaster_hopper_drain_3.jpg|200px|drain 3]]
|-
| colspan="2" | Grasp the latch.
|-
|}
{| class="infobox" cellspacing="5" style="width: 2em; text-align: left; font-size: 100%; line-height: 1.5em;"
! colspan="2" class="infobox-image" | [[File:blaster_hopper_drain_2.jpg|200px|drain 2]]
|-
| colspan="2" | Move the magnetic brace.
|-
|}
 
If you need to change the blast media, there is a drain hatch at the bottom of the hopper.
 
The latch holding the hatch closed is weak, so there is a magnetic brace helping hold it closed.
 
Use a tray to collect the media.  Otherwise it drains onto the floor.
 
=Adding Media to the Hopper=
 
Open the hatch on the side of the blast cabinet and pour the media into the hopper.

Latest revision as of 13:58, 15 October 2024


Link to: Metal Shop main page

Link to: Metal Shop tool list

This tool is used in Brackets tutorial 3.


Sand Blaster
A happy blaster
General Info
Make Cyclone Manufacturing
Model DW-7335 (obsolete)
Serial Unknown
Specs
Manual Manual for a similar model
Asylum Info
Location Metal Shop
Rubric
Training Tool classes
Testing Tool testing OR come to the shop on Tool Testing Night
Restrictions RED


No lead warning.pngBlaster dust hazard.pngGoggle mask.png


Warning Safety glasses Eye protection required!



Description

A sand blaster mixes abrasive grains with a jet of compressed air that's used to abrade the surface of a (usually metal) part. This cleans paint, rust, and other forms of dirt off the part; it also roughens the part's surface. The blast gun is enclosed in a sealed steel cabinet. The user manipulates the tool with thick rubber gloves that pass through the wall of the cabinet.

The sand blaster cabinet is located in a small room within the metal shop on the south wall adjacent to the fenced-in outdoor porch.

Sand blasting is the LAST stage, not the first, in cleaning a part and preparing the surface for finishing.

Do not use the sandblaster to clean heavily rusted pieces. This would be a slow, inefficient way to do that and is likely to clog and damage the equipment. After testing for lead, remove surface rust with wire brushes, manually or with a power tool attachment. Only then is the piece ready for sandblasting.

Warning "Sandblasting" is a misnomer. NEVER use actual sand in a blasting process.


Use For

  • Steel
  • Stainless steel
  • Zinc-coated (aka galvanized) steel
  • Aluminum, titanium, brass
  • Painted metal (abrade with wire brush or sandpaper first)
  • Lightly rusted parts after initial cleaning

Do Not Use For

  • Lead-based paints
  • Asbestos
  • Greasy or oily parts
  • Massively rusty parts
Warning Use a lead-test swab to verify that paint is NOT lead-based!


Warning If the sandblaster becomes contaminated with lead the media must be disposed as TOXIC WASTE and the cabinet must be thoroughly cleaned out!


Personal Safety

Goggle mask.png
  • NEVER use silica sand as an abrasive media. Always use media designated for blast use.
  • Test paints and coatings for LEAD using the test swabs provided. The swabs change from yellow to red when lead is present. If lead is detected do not clean with the sand blaster.
  • Wear safety goggles. Eyeglasses don't protect against abrasive dust.
  • Wear respirator or N95 or better mask when using the machine or working in the room when the machine is being used. All fine dust is hazardous to breathe.
  • Place the workpiece in the blast cabinet and close the hatch tightly to avoid dust escaping from the cabinet. Check that doors on both ends are latched close along with both hoppers. When removing workpieces, some dust will unavoidably mix with the room air. Wear a dust mask at all times when working in sand blast room.
  • Cabinet gloves and viewing window are at a fixed height above the floor. If they are too high, a stand should be provided. Use care on unstable stands.
  • If the blast gun is not properly grounded to the cabinet, static electricity can cause shocks to the operator. If static shocks are encountered, check the ground connection to the gun.
  • Use caution when lifting heavy parts into the sandblaster cabinet.
  • If a part is too large to allow the hatch to close and seal, do not operate the sandblaster.
  • Use caution with the foot pedal and hoses. Place them where the trigger cannot be accidentally depressed when the hoppers or cabinet are open.

Shop and Equipment Care

  • EMPTY THE SAND BLASTER CABINET OF USED MEDIA AFTER EVERY USE. Sift used media into provided bucket matching the type of media you are using, and dispose of filtered waste in trash. Do not leave machine full of used media. Do not "top-off" with clean media in hoppers with used media. If media is too spent to use effectively, discard and start with fresh media. Mixing new media with partially spent media wastes media and makes an ineffective blast medium.
  • Shop standard media is brown aluminum oxide. If using alternate media, such as glass or ceramic beads, empty cabinet and thoroughly clean rails etc. inside the cabinet, both before and after using this media.
  • Do not abrade greasy or oily parts in the sandblaster. These can cause the media to clump and clog the flow lines, and damage the equipment.
  • Do not move the blast cabinet when it is full of abrasive media.
  • Do not point the blast gun at the rubber gloves or the cabinet window or the cabinet ceiling light.

How to Prepare Metal Workpieces for Blasting

Lead test swabs
How to swab
Color when lead is detected
Color when no lead is detected
Warning If the machine becomes contaminated with lead, tell the facilities manager so that the media can be safely disposed. It is toxic waste. It is not legal to throw the media away yourself. The blast cabinet must be scrubbed to remove toxic dust.


  1. TEST FOR LEAD. Lead and lead paint are forbidden on this machine. Use a lead test swab to verify that there is no lead on the surface of your workpiece.
    1. Moisten the tip with water, wait 2 seconds for the reagent to dissolve, then rub the surface.
    2. If no lead is present the swab stays yellow-orange. It turns crimson if lead is present.
  2. Clean off any massive rust with a grinder before placing the workpiece in the sandblaster. Large flakes of rust can mix with the blasting media and clog the flow lines leading to the gun.
  3. Degrease the workpiece. If greasy or oily, clean the workpiece with a solvent or a water-base cleaner such as Simple Green. Make sure it is dry before placing it in the blast cabinet.

Sandblaster Parts

The sandblaster and dust collector installation

The sand blasting room has ventilation to the outside. Turn on the ventilation using the timer switch on the wall next to the CNC plasma cutter.

The sandblaster has three free-standing components. The cabinet is the largest, and the other two are the components of the two-stage dust collector to the left of the cabinet.

The sandblaster has two bays. Presently the RIGHT bay is the only one used. Our compressed air service is only sufficient for operating one bay.

Turn on the dust collector (located in the back of the room) by plugging it and the air filter into the outlet on the left.

Turn on the cabinet lights with the small switch on right hand box.

The sandblasting action is controlled with the foot pedal on the floor or stand. Always stay aware of the placement of the foot pedal so it's not accidentally triggered.

Instructions For Use

The power switch for the sandblast room ventilator is located around the corner on the back wall adjacent to the CNC plasma cutter.

1. Ensure that the air compressor is on. It is located in the closet in the loading dock area.

2. Turn on the room ventilator. This switch is in the CNC Plasma area (see image on right).

3. Put on goggles and a dust mask or respirator.

4. Check the air pressure at the regulator on the blaster cabinet. Target pressure is 60 - 100psi.

5. Plug in the two-stage air filter at the end of sand blaster room, and cabinet if that's not already plugged in.

6. Check that the media hoppers were emptied by the last user. If they were not, empty and sift the media before beginning.

7. Add media to the hopper where you intend to work, pouring it through the grate in the cabinet. The correct amount of media is between 10 and 20 lbs, depending on the media. Too much media will compact in the hopper can clog the feed hose. Make sure the feed tube is down in the media.


8. Place the workpiece in the cabinet and latch the hatch shut. Confirm that the doors on both ends of the cabinet are latched, as well as both hoppers.

9. Arrange the stand as/if needed and place the foot pedal in a convenient spot. Be careful of tippy step-stand.

10. Turn on the cabinet light switch on top right of the cabinet. Optionally, also shut off room light for better visibility into the cabinet.

11. Stick hands into rubber gloves, grasp blasting gun and step on the foot pedal to BLAST!!!

  • If no media appears to be coming out, and no abrasion is happening, check valve lever on front of cabinet.
  • While the air is flowing, it may be necessary to wiggle the dip tube that reaches down into the hopper where the media is located.
  • After a long period working, the media may migrate from the hopper in use to the hopper not in use. Simply place baker's tray under opposite hopper, open to collect media, close, and pour the tray back into the hopper in use. BE CAREFUL WHEN DOING THIS to stay always aware of the foot pedal location, so as not to accidentally trigger it while the cabinet is open.
  • Open the cabinet and inspect your work periodically. Give the hatch a thump and wait a minute or two for the dust to settle before opening it.

12. When finished, place baker's tray under the hopper, empty the media out of the machine and carefully pour through the sifter back into the proper "in-use" bucket. Empty both hoppers as media will have migrated during use.

13. Sweep loose media off the floor. Loose media is a respiratory hazard and can create a slip hazard. Remove used paper towel, gloves etc., from room; empty dust pan and waste from sieve into trash can in main metal shop.


Grasp the latch.
Open the hatch, part way at first to begin opening, then fully to get all of the media out.
The total quantity of media in the hopper should be 10 - 20 lbs, or 3 - 5 quarts in volume of aluminum oxide media.
Pour the media through the screen provided to remove flakes.
Flakes can block the gun and damage the hoses.
Move the magnetic brace.

Draining Media from the Hopper

Empty the media hoppers and sift the media after each use. Each user in this shared facility must have access to good, clean media, not media contaminated by rust and remnants from the previous user's project.

Place the baker's tray under the hopper before opening it.

Sift media into the proper "In-Use" bucket.

The latches holding the hopper hatches closed are supported by a magnetic brace helping hold the latch in place. Slide the brace out of the way before opening the latch. Open part way to allow media to begin to flow, then open the rest of the way. Always replace magnetic braces to support the latch after closing.

Adding Media to the Hopper

Open the hatch on the side of the blast cabinet and pour the media into the hopper.

Troubleshooting

PROBLEM CAUSE REMEDY
Excessive Dust Dust collection system malfunctioning Empty canister and replace or clean filter bag
Abrasive media worn out Replace media
Too much media in hopper Remove excess media
Uneven blasting action Too much media in hopper Remove excess media
Top of abrasive tube covered Move media away from top of pickup tube
Inadequate speed or efficiency of blast Media worn out Replace with new media
Worn blast gun parts or hoses Inspect/adjust/replace parts
Too much blast material Remove excess material, 10-15 pounds max
Too much air Regulate air to 70-90 PSI
Too little air Check shop air; make sure compressor is still on
Poor Blast Pattern Nozzle worn Replace nozzle
Static Electricity Dry environmental conditions Install static electricity band; Get lined gloves
Change in humidity Stand on cardboard/rubber mat;

Get lined gloves

Faulty ground wiring Check electrical wiring
Surging Too much media in hopper Remove excess media
Unit won’t blast Excessively worn blast gun parts Properly replace parts

How it Works

The sandblasting gun is a pneumatic device called a Venturi. Compressed air is fed into the end of the gun and issues through the nozzle. Inside the gun the air jet traverses a side entry that is connected to a dip tube that reaches into the pile of media in the hopper.

The jet of air from the high pressure side entrains slower-moving air in the side entry, causing it to be drawn up through the dip tube. Feeding 100 psi air from the air supply results in 2-5 psi of suction at the dip tube.

Gun and dip tube
The blast gun with hose connections. Top: High pressure air feed; Middle Right: Blast Gun; Left: Suction hose with dip tube.
Venturi
A schematic view of the blast gun.

The suction in the dip tube collects media from the hopper and feeds it into the air jet. Aluminum oxide has a density almost double that of glass. Excessive media in the hopper will cause it to compress in the lower portions and make it unflowable.

The correct amount of aluminum oxide media for reliable operation is about 1 gallon, roughly 15 lbs.