Based on the mini cyclone available at
www.clearvuecyclones.com I had a go at making one myself (from bits I had in the workshop).
It makes quite a number of compromises to the design - namely using 4" pipe inside a 6" cylinder (made by heating some perspex sheet with a heat gun!)
The red bit is part of a scavenged traffic cone!
It's very much a bodge job; made to see if this stuff really works. The answer is yes, though you can see from the video that some dust spirals the wrong way around the outlet tube. I'm sure this is because the tubes are way too big for the cylinder size.
Having said that - it does do a good job of separating dust. In the video, I'm throwing handfuls of wood dust into the inlet, and at the end, there was only a fine sprinkling on the bottom of my dust extractor bin.
It's certainly made me interested in making a slightly bigger one, but Bill's design is too big for my little workshop. Sdantonio - I've sent you a PM, and would love a copy of the cyclone plans!
http://spikyfish.com/cyclone/tube1.jpg http://spikyfish.com/cyclone/tube2.jpg http://spikyfish.com/cyclone/cyclone1.jpg http://spikyfish.com/cyclone/cyclone2.jpg
The video is over 11MB, and 'on its side', as I was using my digital camera in portrait mode (not really suited to recording video).
http://spikyfish.com/cyclone/running.avi