Created: March 2000
Updated: January 28, 2012

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Summary

Foreword

Applicability

Risks

Background

Solutions

Sharing

Vendor Games

Success

Acknowledgements

Financial Help

Navigation

Summary

Most small shop workers, particularly woodworkers, get fed so much bad information by our small shop vendors, that most really do not understand how much unhealthy dust we make, how little of this dust it takes to pose very serious short and long term health hazards, or what it really takes to have good dust protection and collection. These Cyclone and Dust Collection Research web pages share more than you ever wanted to know about airborne dust and the health hazards it causes. They share how upgrade your existing dust collector, cyclone, ducting and shop vacuums for better fine dust collection. They share how to inexpensively test your dust collection airflow, filtering and air quality. They share plans to build my dust collection solutions that protect my family and me. These easy solutions let you get good fine dust protection without having to master the complex air engineering science that air engineering firms who guarantee customer air quality use to provide good fine dust collection.

Almost all small shop dust collectors and cyclones fail to provide good fine dust collection. They consistently do not move the air volumes or provide the fine filtering that decades of research by those firms that guarantee customer air quality show we must have to get good fine dust collection. Almost all small shop dust collectors only move enough air for good “chip collection” meaning picking up the chips and sawdust we would otherwise sweep up with a broom. In spite of contrary advertising claims all dust collectors and all small shop commercial cyclones provide such poor fine dust separation that filters good enough to protect our health quickly clog and need such constant cleaning that these very expensive filters normally need replaced in full time commercial shops every three months. That is why most commercial shops instead vent their cyclones and dust collectors directly outside. Between the high cost for good fine filters and poor separation, almost all small shop vendors sell undersized more open filters that do not clog so quickly. When vented inside almost all small shop dust collectors and cyclones so quickly raise the fine unhealthiest airborne dust levels that typical small shop workers including hobbyists get more fine dust exposure in a few hours than a full time shop worker receives in months in a commercial facility that vents outside or uses fine filters.

Disgusted by all the bad advertising and pathetic performance of my "best" magazine rated cyclone I built my own cyclone that moves ample air for good fine dust collection plus provides much better fine dust separation. The better a cyclone separates the less often we must clean our filters and the longer our filters last. Independent medical school testing shows my innovative cyclone provides five times better airborne dust separation than its nearest competitor. This means my design lets the fine filters we need to protect our health last many years instead of a typical three months. These pages include detailed scalable plans to build my unique fine dust separating cyclone. I strongly recommend all either vent outside or use my cyclone design if you recycle your air through fine filters. You can also purchase my cyclone design from Clear Vue Cyclones or buy a cyclone kit from my son. I only authorize Clear Vue Cyclones and my son to sell my cyclone design.

Foreword

This site does a little well deserved small shop vendor bashing. Our small shop vendors know better yet still create a dangerous false sense of security. Rather than take the time and cost to provide equipment that protects customer health, most small shop vendors simply sell their same old dust collector, cyclone and shop vacuums then add a finer filter so they can claim health protection. Decades of shared research from those firms that guarantee customer air quality found that we actually need just about three times more total airflow to do a good job of collecting the fine dust as we do to just provide good “chip collection” at the same tools. We need lots more total air volume to surround our tools with fast enough moving air to keep normal room air currents from spreading the fine dust. They found that if we do not do this we do not collect the fine dust at the source. Once the fine dust escapes it spreads so quickly and it takes so little to fail an air quality test that there is no way an air cleaner or exhaust fan can clear the air fast enough to avoid failing an air quality test. Decades of experience shows the only safe way to control fine dust is to capture it as it gets made. These firms that guarantee air quality share exactly what we need to do to capture this fine dust as it gets made for almost every size and type of stationary tool. Because small shops use the same smaller tools we can use this same information. They show we have zero chance of good fine dust collection unless we start by upgrading most stationary hoods to trap and control the fine dust, then move about three times more air than it takes to provide good “chip collection”, then we must either clean that collected air or vent it outside.

Applicability

Although woodworking dust inspired this site creation, all fine airborne dusts endanger our health. Air quality experts recommend that fiberglass workers, coffee roasters, granary storage workers and others with fine dust exposure read and follow the recommendations shared on these pages. Three large industrial dust collection providers who guarantee air quality require their air engineering and sales staff read this site and they recommend customers read these pages.

Risks

The medical research gives bad news. Most inhaled dust contains toxic chemicals that can cause irritation, allergic reactions, poisoning, and even cancer plus long term exposure to fine airborne particles causes a steady loss of respiratory capacity.

The research and insurance data show most develop health problems from the toxic chemicals found in and on wood. Most woods contain toxic chemicals that trees use to protect themselves from natural predators. Additionally, the molds that grow on wood make some of the most toxic chemicals known to man. In large doses these toxic chemicals can kill us, cause massive nerve damage, and potentially deadly allergic reactions. In typical smaller exposures these toxic chemicals still cause nerve damage, allergic reactions and increase our risk of cancer. Yew, oleander and a few other woods are deadly poisonous. Exposure to beech, cedar, cypress and some other woods increases our risk of cancer, particularly some nasal cancers. Some woods like cedar, cocobolo, mahogany, maple, myrtle, oak, padauk, redwood, rosewood, walnut, etc. contain chemicals that can build potentially life threatening allergic reaction in as little as one exposure. A good Wood Toxicity Table shares the risks from the toxic chemicals found in wood. Woodworking also exposes us to other toxic chemicals found in our finishes, solvents, strippers, glues, fillers, etc., plus other toxic chemicals may contaminate wood such as herbicides, insecticides, preservatives, lead, etc. Most woodworkers develop mild wood and mold allergies after a decade or so. Roughly one in fourteen builds such strong reactions they must stop woodworking and roughly seven out of a thousand develop potentially life threatening allergic reactions. I receive a few emails each week from woodworkers who like me enjoyed woodworking then suddenly found they are so allergic to wood dust or the molds that grow on wood they cannot even go into their shops without strong allergy symptoms. The toxic chemicals found in and on wood only represent the immediate half of the problem.

All fine invisible dust poses a serious long term problem and fine wood dust is particularly bad. The peer reviewed medical research clearly shows every fine invisible dust exposure causes a tiny but measurable respiratory capacity loss and some of this loss becomes permanent, so all exposed to fine invisible dust develop respiratory damage and capacity loss. This dust poses so much health risk that just two tiny thimblefuls of fine invisible dust is enough for a large two-car garage based shop to fail an EPA air quality test. Airborne wood dust is particularly bad due to the toxic chemicals it carries and because of the shape of fine wood dust particles. Just like asbestos and fiberglass the sharp often barbed microscopic wood dust particles lodge in our tissues where they poke, cut and tear cells to cause permanent damage and scaring. We have enough lung capacity that unless we engage in strenuous athletics or have very high exposures most do not notice these adverse effects until our later years. Then the accumulated damage seriously reduces our capacity and worsens other age related diseases. Unfortunately, for small shop woodworkers and others with high fine invisible exposure the damage can eventually build to potentially deadly results.

Between the toxic chemical and fine dust exposures the insurance data shows one in eight full time woodworkers in facilities that vent their dust collection outside develop health problems that force them into an early retirement. This should terrify small shop workers because even with a tiny fraction as much time spent doing woodworking we often have much higher exposures. Careful air quality testing shows that typical small shop workers including hobbyists that vent their dust collectors and cyclones inside receive more fine dust exposure in a few hours of woodworking than full time professionals that vent their dust collection outside receive in months.

Background

Although sharing my dust collection experience does a little well earned vendor bashing, please understand that what I am really sharing is that even with a strong engineering and scientific background I ended up blindsided and left with serious fine dust triggered health problems. Please do not fall for the same vendor advertising nonsense that screwed up my health and inspired me to write these web pages.

Most small shop workers assume wrongly that fine invisible dust exposure poses no serious risk, or we receive so little exposure it represents little risk, or that we use ample protection. Early in my woodworking career a big redwood project taught me about the need for good fine dust protection. For the next thirty years when making fine dust I used a good NIOSH approved dual cartridge filtered mask and kept a fan exhausting the air in my shop which is the minimum all woodworkers should do when making fine dust. I also foolishly used an expensive ceiling mounted air cleaner and various portable dust collectors all of which worked poorly. As I built up my tool collection for retirement I wanted to work year round instead of avoiding the hot summers and cold winters with the big exhaust fan running. I foolishly followed the considerable forum and magazine advice installing the top magazine rated cyclone system. I used that vendor’s duct design, their ducting, and their recommended fine filter upgrade. That expensive impressive looking system with its fine metal work left a clean looking shop that hospitalized and nearly killed me.

That expensive top rated system failed all the way around. Because almost every other small shop vendor copies this same cyclone design they all share similar problems. The cyclone blowers fail to move the air that decades of air engineering show we must move at our stationary tools to get good fine dust collection. They forget to tell us that we need to change almost every tool port and hood to trap and control the fine dust or their system had zero chance of good fine dust collection. Their terrible duct design uses a too large main with tiny constrictive as small as 1.25” down drops. Unlike the high pressures that our vacuum cleaners generate, air at dust collection blower pressures compresses so little that the constrictive down drops kills the airflow and air speed we need to collect the dust plus causes oversized main ducts to build up piles and plug constantly. These piles pose a serious fire hazard. The measured airflow of these systems is often far worse than the portable dust collectors they replace, so they provide terrible dust collection. Additionally, these cyclones provide dismal cyclonic separation freely passing almost 100% of the fine dust so the fine filters clog constantly. My cyclone also had a design problem that caused the cone to plug whenever I used my planner. Most vendor supplied expensive fine filters freely pass the unhealthiest invisible fine dust, plus these too small filters clog constantly then quickly wear out. My vendor blasted the filter with a fast moving air stream that quickly wore right through the side of the filter. Clearing the filter, cyclone and ducting clogs took more time than my woodworking and left me and my shop covered in the fine dust I installed this expensive cyclone to avoid. I kept using this system because it was advertised to protect my health. Others with identical problems continue to complain on the Internet woodworking forums. Many hate this top rated vendor and call them an outright fraud. Sadly, the long often nasty discussion threads that deal with these undersized and poorly functioning dust collectors and cyclones quickly get deleted because the vendors pay to support the forums and pay salaries plus commissions to “volunteer” forum administrators. These Internet forums got flooded with totally unwarranted praise for my cyclone supplier because they paid a 10% sales commission to forum administrators and respected posters if one of their on-line posts results in a sale. Worse, this same vendor pays shills to attack other products and those who criticize their products.

After just three months of using this piece of junk an apparent heart attack hospitalized me. My doctors found my respiratory tissues clogged with imbedded fine wood dust that kept triggering a worsening allergic reaction and that cut the oxygen my heart needed. The resulting scaring cost me over half my lung capacity and left me supplemental oxygen dependent. I vowed to fix my dust collection amply to return to my lifelong woodworking hobby and sometimes profession.

When my health failed to improve I purchased expensive certified air quality tests. The air quality tests found my home badly contaminated by fine invisible wood dust three months after I stopped woodworking. My garage based shop tested clean until my air quality inspector started my cyclone. Then his test meters showed my so called "fine" cyclone filter blew out so much stored fine dust that my shop failed its air quality test before we did any woodworking. His airflow test showed that cyclone moved about one third the vendor advertised air flow. My inspector said this unit moved far too little air for good fine dust collection. Air quality tests while we made a little dust proved him right. My expensive cyclone advertized to protect my health let my shop air quickly fill until the air could hold no more airborne dust. The dust level failed every different air quality test. This high dust level also contaminated my home every time I went between my garage shop and home. This inspired me to aggressively clean up my shop and home, plus research further.

Solutions

Government regulatory agencies started requiring good chip collection in the 1920s to avoid fires and other safety concerns. Research tempered by generations of experience came up with needed hoods, air volumes, and air speeds to provide good “chip collection” which means collecting the same dust we otherwise sweep up with a broom. The major vendors share their hood designs and airflow tables that show exactly what air volumes and air speeds we need at almost every size and type of stationary tool. Because most small shop stationary tools are identical to smaller commercial tools we can use the same tables. Our small shop stationary tools mostly need about 350 cubic feet per minute (CFM) of air moved at a speed of 4000 feet per minute (FPM) with decent hoods for us to get good “chip collection” that keeps our floors and work surfaces clear.

Sadly, most small shop workers ignore another important concern. The National Fire Protection Association (NFPA) writes the building and fire codes that most communities enforce. These codes require that dust collectors and cyclones go outside behind explosion fire proof barriers unless they are fully certified as both fire and explosion proof. Placing this equipment outside results in most of the fine airborne dust collected being simply blown away into the outside. When small shop owners put our dust collectors and cyclones indoors we ignore the fire risks and fill our shops with that fine airborne dust.

Compared to traditional “chip collection” many want us to wrongly believe that fine airborne dust collection remains a poorly understood black art. The major firms that guarantee customer air quality long ago mastered good fine dust collection and share freely exactly what good fine dust collection requires. This technical engineering information required translation which my professor and engineer friends helped me provide. Good fine dust collection requires some work, but remains doable. The expert firms found that airborne fine dust behaves more like a gas and spreads so quickly that air cleaners and normal sized exhaust fans fail to clear the air fast enough to avoid unhealthy exposures and to avoid failing all the different air quality tests. They learned good fine dust collection requires that we must collect the fine dust at each source as it gets made then get rid of that dust. To do this they found we must:

Most fine dust escapes from around our tool hoods, so we must start by upgrading our tool hoods to better trap and control the fine dust. If we do not start by upgrading most tool hoods to block and control the fast moving air streams to control the fine dust we will not capture the fine dust. Festool and a few other vendors now make some tools that prove if our tools totally contain the dust as it gets made then a good vacuum provides excellent fine dust collection. Most cannot afford these expensive tools plus our larger stationary tools lack good fine dust containment so for our existing stationary tools we almost always must upgrade tool hoods.
Even with better hoods fine dust also escapes from all around the working areas of our traditional tools, so to get this additional dust we must rebuild our tools or move the far more air it takes to pull in the fine dust. We all know that the lightest breath can move the dust particles we see in a beam of sunlight so we wrongly assume that our dust collectors that move lots of air and pickup large chips with ease will also collect most of the fine dust. Years of testing and experience show we actually need to move about three times more air to collect the fine dust than it takes to provide good “chip collection” which picks up the dust we would otherwise sweep up. We all know why we have to move more air if we think about using our shop vacuums. A shop vacuum on blow will move stuff all over, but on suck we can only pickup right next to the end of the vacuum nozzle. Blown air hangs together until slowed by resistance and normal room air currents. Sucked air instead comes from all directions at once so the airspeed for sucked air falls off very quickly. It actually falls at about four times Pi times the distance squared, meaning same formula that computes the surface area of a sphere. This rapid drop in airspeed means our vacuums only pick up dust within an inch or so of the collection nozzle.

The airflow experts found that we really need to surround our stationary tools with a “bubble” of air moving at least 50 feet per minute (FPM) all around our tools out to a distance of more than a foot. To do this requires moving lots of air, roughly 1000 cubic feet per minute (CFM) at the same small shop tools that only need 350 CFM to get good “chip collection”. These experts that guarantee customer air quality found most small shop stationary tools need about 1000 CFM airflow to collect amply to meet EPA and medical air quality standards. The five times easier ACGIH standard still requires about 900 CFM and the fifty times worse OSHA recommendation only requires about 800 CFM.
Since air at normal dust collection pressures will not compress hardly at all, the larger volumes of air we need for good fine dust collection require us to almost always enlarge our tool ports.
Get rid of the fine dust. Venting outside provides the best way to get rid of the fine dust. Thousands of shops even located in the colder regions of Canada show that use of infrared heaters more than compensate for the temperature losses of venting outside even in the coldest of weather. If we choose to vent inside, then the medical experts recommend use ASHRAE certified 0.5-micron fine filters. The filter makers recommend that at typical dust levels from woodworking we need at least one square foot of filter area for every two CFM of airflow. This means a typical 1.5 hp dust collector that moves a real 600 CFM airflow really needs a 300 square foot filter. It also means the recommended 1000 CFM for good fine dust collection requires at least 500 square feet of filter material. The commercial shops that use these expensive fine filters change them every three months. Small shop woodworkers who use pressure guages to monitor the filters find we need to change our filters at least yearly to maintain good fine dust protection.

Sharing

When my respiratory specialist saw my solutions he convinced me to share. He said far too many small shop workers contaminate their shops and homes. This causes them and too many family members serious dust related health problems. We wrote a long Internet forum post article that addressed fine dust risks and it shared my fine dust collection innovations. It challenged most accepted dust collection information and exposed why the dust collectors and cyclones our small shop vendors advertize to protect our health actually create dangerously high airborne dust levels. This article shared why fine invisible dust reduces almost every small shop worker's respiratory capacity. It shared why fine invisible dust causes many other problems including COPD, asthma, serious allergies, poisoning, nerve damage, and even cancer. This article generated too many questions and lots of complaints which triggered spectacular Internet wood working forum wars. We responded and wrote two more long articles.

Our articles generated excessive email, upset, questions and confusion. In 2000 I built these Cyclone and Dust Collection Research web pages to address this confusion. These pages shared the medical risks, recommended controls, and frequently asked questions with responses. These pages shared air tests for every major brand and size dust collector and cyclone. These tests disclosed an industry wide problem with all advertising maximum airflows instead of real airflows which run about half the maximums. Our tests confirmed most sell fine filters that freely pass particles twenty times larger than advertized. Our tests showed almost all small shop dust collectors and cyclones should be put outside and only vented outside because when vented inside these units caused virtually every shop we tested to fail with dangerously unhealthy airborne dust levels even when not making fine dust. Almost any airflow launches previously made dust so when dust collectors and cyclones get vented inside, small shop workers need a good dust mask whenever in their shops. Otherwise, our lungs do the air filtering. Our tests showed our dust collectors and cyclones work so poorly that just a few small shop hours exposure generates more fine invisible dust exposure than full time large facility woodworkers receive in months. With their much lower exposure levels full time large facility woodworkers all lose significant lung capacity during their careers and roughly one in eight gets forced into early medical retirement.

Vendor Games

Small shop vendors, particularly in these difficult economic times, engage in some pretty questionable sales nonsense. My engineer professor friends in 2006 tested every major brand of small shop dust collector and we tested every major brand of small shop cyclone in 2008 and 2009. We tested for airflow, separation ability and filtering. Our results proved so dismal that when I shared those results on these web pages immediately three vendors threatened costly legal suits I cannot afford to defend, so I had to pull down these test results. We discovered:

All vendors advertise maximum airflows but in real use the overhead resistance from our tool hoods, ducting, dust collector components, and filters cuts actual working airflow to less than half of the actual maximum airflows.
Of all the vendors we tested only Delta and WMH Tools (Jet, Powermatic and Wilton) advertised maximum airflows we could duplicate with our testing. Our tests led us to believe many small shop vendors create their advertized airflows in back rooms with no testing whatsoever.
The magazine tests I critiqued and the test I oversaw had two dust collector vendors submit larger blowers and motors than they actually sell.
We found the cyclone and dust collector vendors use two tricks that they talked the magazine testers to use that create badly falsified maximum airflows.
1. The more air a blower impeller pushes the more power it draws and the higher the amperage draw on our blower motor. When a blower tries to move too much air then the motor draws too many amps. When the blower draws too many amps hopefully our circuit breaker pops before either our house wiring or the motor burns up. Professional grade dust collector and cyclone blowers get carefully engineered with impellers, blower inputs and blower outlets sized just right so even if we knock a hose loose our circuit breakers will not pop, our house wiring will not burn up and our blowers will not burn up. Sadly, our testing disclosed that all but the Jet and Powermatic dust collectors and cyclones failed to safeguard our systems from blowing circuit breakers, ruining shop wiring, and potentially burning up motors.
2. We also found most vendors supply their units with a large inlet that in real use they often either neck down to actual ducting size or split into a wye with two smaller duct connections. When tested with the larger opening we consistently found every vendor except Jet and Powermatic moved enough air that the motor amperage rose dangerously above the motor’s rated amperage.
We also discovered one dust collector vendor and most cyclone vendors further increase their maximum airflows with another ploy. Dust collectors and cyclones force the air to move in a tight separation spiral and that adds lots of resistance that kills overall airflow. Air engineers get this airflow back by using oversized impellers. They size cyclone impellers to move the most air a motor can move without exceeding its amperage rating. We found one top rated dust collector vendor and every major cyclone vendor except Jet and Powermatic provided sufficiently oversized impellers that their units when tested without restrictive normal ducting pulled far more amps than the motor could tolerate, some as much as three times too many amps.
Sadly, the magazine tests rate airflow without stopping the test as soon as the motor amps go above the motor rating. Our testing cut off the tests as soon as a motor exceeded its rated amperage and found much lower ratings for all the top rated cyclones and top rated dust collector.
I discussed the magazine tests with the crews who did the testing. Three dust collector motors burned up during two magazine dust collector tests and four cyclone motors burned up during two cyclone tests. In other words, instead of providing about half the advertised airflow in real use, these dust collectors and cyclones actually provide far less than half the advertised maximums.
Our vendors use the wrong standard to rate their filters which fills our shop air with dangerously high amounts of fine dust. There are two standards used to measure filtering efficiency. ASHRAE provides the standards for indoor filters and their standard requires testing filters when clean and new. Our small shop vendors ignore this standard and instead advertize fully seasoned filtering levels. Over time dust builds up in the filter pores and this dust does not come out with automated machine shaking filter cleaning. It takes a small shop filter a year and a half or more to fully season. When a filter absorbs all the dust it can we call this filter fully seasoned. The dust cake in a fully seasoned filter provides roughly twenty times better filtering than a brand new clean filter. Unfortunately, a blast of air such as from turning on our dust collector or cyclone will blow a huge blast of the finest invisible particles right through a fully seasoned filter. Likewise, even a little over cleaning causes a fully seasoned filter to lose its seasoning and again pass fine dust, so during the seasoning process and afterward our lungs end up filtering the fine invisible dust. This is why ASHRAE requires rating only clean new filters for indoor use and it also explains why my so called fine filter failed to provide good protection.
Our vendors inappropriately size our filters based on the area needed for a clean new filter with no seasoning. At typical dust loading we need about one square foot of filter area for every two CFM for a 0.5-micron filter. That drops to one square foot of area for every 10 CFM for a 20-micron filter which is what most vendors sell and claim are 1-micron filters. So instead of our 1.5 hp dust collectors that in real use move about 600 CFM coming with 300 square foot filters, most come with 30-micron bags with only about 30 square feet of area or new pleated filter cartridges that only have about 100 square feet of area. Just like too open filters freely pass the unhealthiest dust, too little filter material creates filters that clog too quickly then rapidly wear out because cleaning rapidly ruins fine filters.
Our testing disclosed dismal separation. None of the dust collectors or cyclones except my design cyclone provided any fine dust separation except through their filters which consistently passed fine unhealthy particles sized up to twenty times larger than the vendors advertised. We found the trashcan separator lids provided 99.9% separation on particles sized 30-micron and less if the airflow stayed below 400 CFM. As the airflows increased soon everything except large blocks got scoured from the trashcans. We then tested all the different cyclones for separation. Cyclones provide separation at higher airflows, but the separation we measured was dismal. None of the major small shop cyclones provided much better than trashcan separator performance. In other words, even the highest magazine rated cyclone was worthless in terms of protecting the fine filters. Independent medical school testing of the cyclone I designed to improve this separation showed it provided 99.9% separation on particles down to 5-microns and smaller. This over five times better fine dust separation makes for less than one quarter the filter cleaning and more than four times the filter life. It also means we can use the fine filters we need to protect our respiratory health.

In summary, we found the small shop vendor dust collectors sized under 3 hp and cyclones sized under 5 hp moved too little air for good fine dust collection. We also found most vendors provide far too open and gravely undersized filter to protect our health. As a result we strongly recommend that most dust collectors and cyclones be placed and vented outside.

Success

More than 10,000 small shop owners worldwide use cyclones of my design and thousands visit this site daily to learn about fine dust risks and collection. I freely helped almost every small shop vendor improve their products. Most small shop vendors made some repairs such as adding finer cartridge filters, but almost all chose to continue selling the same dust pumps that fill our shops with dangerously unhealthy amounts of fine invisible dust. Two vendors I helped flagrantly stole and patented variations on my work, falsified information and emails about me on their web pages, and have for the last five years run a nasty campaign using Internet forum administrators and posters to discredit me and these efforts. One of my friends recently laughed when I moaned at how much this terrible campaign continues to cost me. He reminded me what Winston Churchill said, “You have enemies? Good. That means you've stood up for something, sometime in your life.”

Acknowledgements

Many helped these web pages develop. They gave me the support and feedback that keeps this information accurate and useful. Jim Halbert, Dr. Rod Cole (Ducting Static), and many others provided books, articles, and Internet forum posts that got my education rolling. Jim Halbert shared his neutral vane upgrade, portable cyclone design, his automated blast gates (see blast gate video), his air measurement pages, his DC remote controller and circuit diagram, and his cyclone vacuum. Jim looks over my shoulder and shares feedback that keeps my efforts accurate and understandable. The air engineer who started the Wood Magazine Dust Collection/Air Filtration forum, Don Beale, spent countless hours where he helped me get the CFM requirement tables, resistance calculator, hood designs, duct designs, and many other portions accurate, and complete. Also, Don sent me enough air engineering reading to earn another degree.

Also I give my thanks that so many other friends helped my cyclone, blower, motor, impeller, tool hoods, ducting, and web page efforts. I thank Bob Lemon, Dan Moening, Mike Worthan, Dale Critchlow, Glenn Paskaruk, Steve Knight, Steve Cater, Daryl Adams, Richard Winchester, Peter Hunt, Jack Diemer, Rodger Holland, and innumerable other local and Internet friends. Also I thank Larry Adcock who created WoodSucker, Chris O'Connor AAF sales manager, Paul Paton Sheldon's blower engineer, Allan Johanson who moderates the Wood Magazine Dust Collection/Air Filtration forum, Dick and Rick Wynn who run Wynn Environmental, Ed and Matt Morgano who did such a great job building up Clear Vue Cyclones, Bushey Enterprises who took over Clear Vue Cyclones and are building it into an even better firm, Lee Styron who runs Shark Guard, innumerable Cal-OSHA staff and contractors, plus many commercial dust collection firms. They help keep me stay focused and relevant, provide discounted components, plus show and share proper fine dust collection technique and components. Many others contributed time, expertise, and even a little money that assisted this effort. Terry Hatfield made me rewrite and add graphics. Linda Vanderwold, CSP shared the Vanwrite® tools that make this site more understandable. I appreciate Steve Hall who gave his time and web designer expertise that redesigned this site so it loads faster, reads better, and navigates easier. I thank each who contributed. Although we get no gold, we created and maintain an accurate information and education source that makes a difference. Clearly many hear our efforts. Our educational efforts helped small shop owners make better choices. I started seriously looking at fine dust collection in 1999 and began shairng these pages in 2000. Since then the small shop vendor community improved their filters, dust collectors, cyclones and advertising claims. Even with these improvements recent testing showed almost every small shop dust collector and cyclone remain dust pumps that leave our shops with dangerously high amounts of the unhealthiest invisible airborne dust so this work needs continued. Meanwhile, I appreciate the prior efforts and help. I think we all deserve a well-earned hand. My personal thanks to all who helped and keep helping!