Dust Collection Research - Cyclone Building Instructions. Instructions. These instructions presume little to no sheet metal skills and a minimum of tools. Over 1. 0,0. 00 small shop owners use cyclones of my design and at least 6. You can build one of these cyclones if you patiently take your time and follow the instructions. Please read the Cyclone Plan page before starting on building your own cyclone so you understand more about this system. Most thumbnail pictures on this page become full sized pictures when clicked. This lets the page load faster for those with slow connections. Introduction. We have over seventy years of chip collection science and at least thirty years of professional fine dust collection science define the minimums we need for good dust collection. Since the 1. 92. 0s fire marshal and building codes required good chip collection in most industrial facilities, so chip collection remains well understood. Chip collection means picking up the sawdust and chips that we would otherwise sweep up with a broom. Good chip collection requires enough air speed to pick up the dust and chip, enough air speed to keep that material moving through our ducts, and enough air volume to accommodate the volumes of dust and chips each different size and type of machine produces. Decades of applied science and practical experience helped the major dust collection firms build tables that show exactly how much airspeed and air volume we need to collect the different materials. For woodworking these tables show we need to maintain a target air speed of at least 3. ![]() ![]() Toilet itself is on the second floor with the base directly below on the first floor in the utility room. Again, no smells. I have a tassel on the rake bar with. Nearly 2,000 automotive mechanics in the Chicago area are about to enter their seventh week on strike, fighting dealers for major structural changes to their employment. FPM) airspeed to suck up the chips and keep vertical duct runs from plugging. To provide a little safety factor most woodworking dust collection engineers design their systems with at least a 4. FPM airspeed. Also, we need at least 2. FPM airspeed to keep horizontal ducting runs from plugging. Finally, most small shop stationary tools require at least 3. CFM) airflow to pull in the volumes of dust and chips they produce. At least thirty more years experience by those firms who guarantee customer air quality also establish well tested fine dust collection minimums. We need the same 4. FPM airspeed for pickup and to keep our vertical ducts from plugging. I just installed a ceiling fan in my daughter’s room. This was a first for me, and I made more mistakes than what I did right. However, in the end, I think it is. Likewise we need that same 2. FPM to keep our horizontal ducts from building up dust piles. The major difference between good fine dust collection and chip collection is we need to move far more air, roughly 1. CFM to get good fine dust collection at our typical small shop stationary tools. At first this requirement to move nearly three times as much air makes no sense because we all know that the slightest breeze will blow dust highlighted in a beam of sunlight. I often ask people to wet a finger and see how far away from their lips they can feel blown air versus how far they can detect sucked air. We can feel the blown air as far as we can reach, but can only feel sucked air when our finger is right next to our lips. Likewise, our shop vacuums only pickup right next to the end of the nozzle. The reason is sucked air comes from all directions at once and blown air hangs together for quite a distance before it disperses. Because airspeed falls at roughly twelve times the distance squared, we lose the airspeed we need to pull in the fine dust before normal room air currents blow it away unless we move lots of air or totally contain all the dust as it is being made. Most tools even with upgraded hoods provide such poor containment we must move more air. This is why good fine dust collection requires that we move about 1. CFM of airflow. Careful testing shows that reducing that airflow to 9. CFM ends up with five times more airborne dust. Reducing to 8. 00 CFM lets fifty times more airborne dust escape collection and airflow below 8. CFM results in such poor fine dust collection that shops subject to inspection would immediately be shut down due to dangerously high airborne dust levels. We need to understand wood dust causes a variety of immediate health problems and some long term adverse health effects. Wood gets much of its strength from silica better known as glass. When looked at through an electron microscope wood strongly resembles bundles of hollow mostly glass rods stuck together with organic products. Think about what would happen if you glued a bunch of glass tubes together then slammed a machete to cut through that bundle. You would end up with a fairly clean looking cut but would also generate lots of tiny broken pieces of glass. This at a microscopic level is exactly what happens even when we hand plane what appears to be a near perfect curled shaving. A particle meter shows that hand plane generates a large amount of fine invisible dust. These too small to see without magnification particles slip by our bodies' natural protections. Then depending upon size these sharp barbed particles lodge at different places in our respiratory tissues where they cut and tear our tissues. As a result the peer reviewed medical studies show every fine dust exposure causes a measurable loss in respiratory capacity and some of this loss becomes permanent. Although our bodies come with more than double the capacity we need for most things, over time the accumulated loss worsens a wide variety of other health problems, particularly other age related and respiratory diseases. Insurance companies used to share on the Internet their data that show 1. This is particularly bad news for small shop and hobbyist woodworkers because the insurance data is for larger facilities that almost always vent their fine dust outside. Typical small shops that instead vent their dust collection inside average about 1. Although private industry spent fortunes to prove that wood dust poses no major health risks, the reality shown by peer reviewed medical studies is that any woodworker who does not protect themselves will experience trouble, often in their later years of life. All fine dusts pose so much health risks that the EPA sets standards of no more than 1. Translated, less than two tiny thimblefuls of the fine invisible dust will cause a large two car garage sized shop to fail an EPA air quality test. The medical experts know fine dust poses so much health risk that they recommend an even tougher standard of only 1. Just slapping our denim shop apron launches enough of this fine dust to fail either an EPA or medical air quality test. Believe it or not, hand sawing just seven inches of 3/4" wood will cause a large two- car garage sized shop to fail these air quality standards. Sadly, most even clean looking shops fail their air quality tests due to a buildup of residual dust. Residual dust consists of that dust either missed during collection or with particle sizes so fine it passes right through our dust collector and cyclone filters. The high silica content in wood dust means this dust lasts a long time. In fact, when a few of the sealed pyramids were opened researchers found considerable wood dust that still lingered settled on every surface. Almost any airflow launches these invisible residual dust particles over and over. As a result, most small shops that vent their dust collectors and cyclones inside build huge amounts of residual dust then just about any activity in our shops launches this dust over and over. Strangely, one of the worst stores for this dust is our so called fine filters. Most filters are open enough that the fine dust accumulates in the filters, so when we first turn on our dust collectors or cyclones the initial blast of air blows lots of this fine dust right through our filters. Moreover most filters use spun polyester fibers which build up a strong static charge from the air flowing over the filter strands. When we turn off our blowers this high static charge attracts lots of fine particles. My certified air quality inspection showed my clean shop immediately failed as soon as we turned on my cyclone before we did any woodworking. That dust came from the surface and inside of the filter pores. The medical experts strongly recommend that vent the fine dust outside and if we have to filter that we use filters that separate down to at least 0. These are really fine filters because there are one million microns in a meter and a coarse human hair is only about 1. Our eyes normally can only see down to about 1.
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