The Bill Pentz cyclone design is now available in kit form, along with a mating blower housing. For those suffering from low ceilings, a belt-drive accessory is in development, delivery expected in January.
If you are not familiar with Bill Pentz's dust-collection web site, it is well worth investing some time going through it. Lots of important and useful info about dust collection, ductwork, air-flow requirements, health hazards of wood dust, and other topics. Bill almost died from the effects of wood dust, and the site is the result of his research as well as input from other woodworkers and professionals. The site is at: