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Dust Related Resources:

For more on extracting dust, modifying tools dust points, noise reduction, and a whole load of other bits’n’bobs check out our blog:

Bill Pentz’s magnificent dust collection website:

A decent discussion of cyclone dimensions, height to diameter ratio etc. based on knowledge of ginning cotton:Abatement of Air Pollution and Disposal of Gin Waste, C.B. Parnell, Jr., E.P. Columbus, and William D. Mayfield. in Cotton Ginners Handbookedited by W. S. Anthony, William D. Mayfield (1994)

A useful stock dimensions calculator, used in producing the cone shape:

A doctoral thesis, by Jette B. Lange on the health dangers of wood dust. This contains a lot of references to good academic, peer-reviewed evidence and information – very useful if you are keen to research this area further.  Effects of wood dust: Inflammation, genotoxicity and cancer

A table of wood toxicity published by Woodworking Australia:

Noise Control Resources:

A decent and comprehensive book, if a bit dry. (Amazon link): Engineering Noise Control: Theory and practice, Fourth edition, David A. Bies and Colin H. Hansen (2009)

Nice site for the basics of soundproofing:

A corporate (Silex) sponsored (but still worth a look) document on sound attenuation:

An interesting Speaker Building website:

A Website called, ‘Resonance Frequency’- more useful info from our speaker building friends –

Automatic Switch Resources

Fine Woodworking article that describes construction of an automatic switch using commercial (expensive) current sensor.

An excellent patent of auto switcher that uses a home fabricated current sensor and a transistor. Has a good circuit diagram and a complete list of parts (towards the end).

A very simple patent of a triac using auto switch – not idea because it is a current matching circuit

A discussion on an electronics forum I started when I was considering my reed switch method:

Bill of materials / things to look out for if you are planning a DS:

Enclosures: old fire doors, kitchen work top, scrap mdf, plywood, angle iron (bracing and joining), sand, lead sheet, thick steel (if you are a wizz with welding). Wood glue, silicone and acrylic sealant, screws. Heavy duty castors, bubble seal (like you get for draft proofing doors and windows).

Internal: old vacuum (can often be found dumped or skipped, with nothing wrong other than dirty filters, or over full bags), old vacuum hosing (loads of these get thrown out, here in the UK you will never need to buy it if you visit your council skip occasionally), compression latches, suitable sized barrels or other containers.

Electrical componants: this is mostly listed in the steps, but you should have no problem scavenging most items, although they will probably need ‘rescuing’ from old appliances.

Cyclones: This is the tricky part, look out for surplus or scrap polycarb from greenhouse constructions etc. May just be a case of buying the right sizes (I got mine from e-bay). I have no personal experience with it, bur you might also consider PETG plastic for the cyclone. It is nearly as tough as Polycarbonate (Lexan) but is easier to machine and apparently does not shatter with solvent even when under tension. The only real problem with the PETG, I am told, is that you need to buy the stress relieved stuff or it bends all over the place when you work with it.

Rough material needed for one cyclone with a little to spare:

Upper Body:
15mm acrylic: 2 of 250mm x 700mm (this is for holding together and mounting. It could be made from plywood or similar instead of acrylic)
1.5mm polycarb: 190mm x 1000mm (this is rolled into the 150mm dia body)

0.75mm polycarb: 800mm x 800mm (cut and rolled up)

Air Inlet:
3mm polycarb: 210mm x 240mm (mitred into box)

1.5mm polycarb: 200mm x 200mm (cut into split circle)

Air outlet:
0.75mm polycarb: 200mm x 800mm (rolled into 75mm pipe)
[OR 160mm length of 75mm dia. pipe]

Hot melt glue to join it all together
I have included the cyclone SketchUp files below. They can be made into SVG files (flightsofideas’s ible shows how) if you want to laser cut or CNC them – if anyone does this let me know how it goes.

Cyclone SketchUp Plans (.zip file 102kb)

Previous Cyclone Step

Responses to Resources and References

  1. Leo Basic

    I was looking for the way to solve dust problem in my small worshop and found your article in Instructables and your site. All I can say is : big thanks, man. I’ll make it and let you know how is working.
    Thanks again

  2. Bongo

    Hey Leo.

    Cool, thanks for that, let us know how it goes send me some pics etc.


  3. John

    Just came across your site while researching extraction for my new cnc machine. I’m in Australia and did some ringing around – it seems no one carries 0.75mm polycarbonate as a standard item. Do you think 1mm will be sufficiently flexible to create the cone?

  4. Bongo

    Hi John,
    The rule of thumb with polycarbonate is that you can ‘cold bend’ it, that is, bend it without putting it in an oven, to a radius that is 100 times the thickness so: R=Tx100 where: R is the smallest radius you can bend to, and T is material thickness.

    If you have 1mm thick polycarb then R (maximum radius) will be 100mm. So technically you will not safely be able to bend it tight enough for either the bottom of the cone or the air outlet. Technically the 0.75mm thickness that I used already bends the rule of thumb quite a bit, but seems to work ok…

    There are ways of getting round the tightest radius at the bottom of the cone – for example, I used part of a tapered polycarbonate pint glass (see cyclone build part 1).

    As for a supply of polycarb – have you tried e-bay???

  5. David

    I looked at your great Dust Sniper project. With regards to Dust collection, I have heard that some folks hit the incoming dust inlet with a fine mist sprayer (water) which instantly turns the dust into mud and alows a much less efficient cyclone design. The ‘mud’ slurry is caught in a collection bin as per your normal design. This would allow a clumsier version cyclone instead of the very high efficency but intricate to build design of Mr Pentz. What do you think?

    Your web-site’s got lots of interesting stuff, and I congratulate you on your enterprises.

  6. Bongo

    Hi David.
    I like the idea, and I think you are right in that the cyclone proportions would not be quite so crucial. It may have the added advantage that you could see really clearly where the ‘mud’ was going (assuming you made a transparent cyclone of course) – that would help diagnosing any potential turbulence problems. On the other hand it might be quite messy and coat the inside with slurry, which could dry on over time and block the view. But that’s not crucial assuming it didn’t create too uneven an inner surface..

    There are other design challenges with a wet system. I guess you would need some way to easily drain off the water from your collection chamber, which might otherwise get quite heavy and unmanageable. Another issue, would of course be the need for water tightness of the motor… If you use a regular external induction motor style impeller, that would be less of an issue. But with the vacuum motors no water could be allowed to ever get through the cyclone – an overfill in the collection chamber, or accidentally sucking up a lump of wood and plugging the cyclone would have to somehow cut the power…

    So yeah, I like the idea, but it would need some figuring out. Maybe your collection chamber could double as some kind of press, so you periodically press the water out of it, ideally recover that for re-misting (though I suspect filtering it would be more trouble than it is worth), and you might even be left with some handy bricketts ready for drying and burning in a woodstove…

    What kind of size system are you setting up? Very interested in this idea, but I haven’t experienced it. Some research and experimentation may be in order – got any good leads? We have yet to rig something up for the new FE workshop so…

  7. Jo S

    Superb website and explanations. I’m afraid I will “waste” many hours trying to digest your good stuff!

    I was thinking about building my own cyclone separator cone, untill last week I was stuck in road works, and suddenly noticed the orange traffic cones… Have you heard of anyone trying to use such a cone as a building block? As some of these cones are 600 mm high, that would leave plenty of flexibility for the upper and lower opening diameters. One would miss of course the visual swirling effects…

  8. Bongo

    Hi Jo! Thanks for the comment. A few people have done the ‘traffic cone cyclone’ (google that for many pics etc), but like you say you do miss the swirling ;)

  9. Jo S

    I built a”traffic cone cyclone”, using your ideas. Works great, and easy to spot in the workshop! Have a look at, I gave due credit to your website.

  10. Bongo

    Hay Jo. Looks awesome! Thanks for the kind words and the share.

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