Created: March 2000
Updated: November 20, 2008

Links

(click on topic to go there)

Suppliers

Design Information

Basic Information

Cyclone Building

Static Electricity

Noise Control

Hazards

Suppliers

Clear Vue Cyclones: http://www.ClearVueCyclones.com now makes cyclones, material movement blowers, and provides material handling impellers. Ed Morgano who started this small firm has been a pleasure to work with and does excellent work.

Wynn Environmental (Dick & Rick): http://www.wynnenv.com/torit_filters.htm has the best pricing and service in providing excellent affordable cartridge filters, 3.5", 4", 5" and 6" clear flex hose in 25' lengths and clamps. They are my recommended source for the Farr and Torit compatible filters in both the washable poly and the less expensive blended cartridge filters. They also offer the Donaldson Torit 0.2 micron fine filters that I need to use to take better care of my poor lungs.

American Fabric Filters: http://www.americanfabricfilter.com/ has some of the best add on filter bags available and will custom make a bag if needed

The Electric Motor Warehouse (Barry): http://www.electricmotorwarehouse.com/120554.htm provided the top quality Leeson compressor motor that was really a 3 hp which has since been upgraded to 5 hp that I used to drive my 14" material movement impeller. They had by far the best service and prices any of us could find on the net, plus if you ask they will mount the bell housing and wire for the proper rotation!

Farr and Donaldson Torit are the two most respected names in commercial dust collection where their customers must pass stringent air quality inspections. It is well worth your trouble to spend some time on both of these vendor’s web pages looking over dust collection and filtering. I used to include the Farr table that showed most stationary woodworking machines found in small shops need about 1000 cubic feet per minute (CFM) airflow for good fine dust collection. Farr also provided the airflows for larger machines such as a CNC wood router needing at least 2500 CFM air volume with 6000 to 7000 feet per minute (FPM) air speed. Both Donaldson Torit and Farr are clear that when venting outside a 30-micron filter is ample, but when venting inside we need to use filters that provide at least 99.9% filtering on all particles sized 0.5-microns and larger. ASHRAE says all filters that vent indoors must be measured when clean and new. Additionally, both firms are clear that indoor filters are so fine that they will quickly clog and kill the airflow needed for good fine dust collection unless we use at least one square foot of filter area for every two CFM airflow. Sadly, every major name brand hobbyist dust collector and cyclone messes up badly on filter fineness and sizing. Most provide one square foot of filter for every 10 CFM of airflow and provide filters that can take a year or more before they build up enough fine dust trapped in the filter pores that they provide the advertized 1-micron filtering. Meanwhile we breath in that fine unhealthiest dust.

Farr also has some good information on filters at http://www.farrapc.com/products/hemipleat//.. This site also has a great mini video clip of what happens during pulse jet cleaning.

Design Information

Just about anybody can make a fairly good cyclone "chip collection" separator. I've seen these made of stacked barrels and all kinds of other things. To make a fine dust collection cyclone you need to get into the engineering, physics and airflow dynamics. I got my start on cyclone design from the Cotton Research Site (http://www.jcotsci.org then go to the top of that page and search for cyclone) and their scientific articles by Funk, Hugs, and Holt. Those articles recommend some major improvements to the traditional agricultural cyclone designs. If this is not enough, then do a Google search on swirl tubes which will take you into the physics behind centripetal tube separators of which a cyclone is a special case. From there you need to look into boundary layer and laminar air flow over various surfaces as without this you are going to pull the fine dust right off the cyclone walls and get poor overall separation. With all that you should then be ready to start engineering designing your own cyclone design.

Basic Information

Bill's "Dust Collection Basics" is my best shot at providing the overview information you need to make sense of dust collection and its technology.

Rick Peters' book is a solid collection of good information on "chip collection": "Controlling Dust in the Workshop" is one of the best, but some of the material is becoming dated such as the grounding discussion and some of the duct sizing.

Sandor Nagyszalanczy's book "Woodshop Dust Control" is also an excellent source of information on "chip collection" and a little more current than Rick Peters' book. It also focuses on "chip collection" instead of fine dust collection, plus inappropriately tries to downscale commercial dust collection designs for hobbyist use. I also strongly recommend reading some of Taunton Press articles and books on dust collection. I've found them to be a great resource. Be aware that this field is changing and evolving so quickly, none are really able to keep up!