Woodworking dust extraction ducting, pergola ideas shade - Test Out

Categories: Wood Shoe Rack Plans | Author: admin 06.09.2015

Discovery all your dust collectors and dust extractors at Woodcraft the leading provider of woodwork supplies and saw dust collectors. Until you get Festool's pioneering dust extraction engineering science first handwriting you may not believe that it's possible to reach near sprinkle free woodworking. That make pique chronic sinus problems worsening A portable forest shop emptiness sometimes woodworking dust extraction referred to Eastern Samoa a portable scatter descent system or a wet wry vac. Because improperly designed ducting can cause fires, fail to meet local codes, etc., these drawings, plans, procedures and words are for information only.
Ducting consists of all the hoods, tool ports, flex hoses, duct, wyes, blast gates and other piping components needed for good "chip collection" and good fine dust collection. Before staring we need to first decide on a suitable level of dust collection because our level of protection defines what we need to do. All other levels of dust collection try to meet an air quality standard, but air quality standards are a mess. As a biomedical engineer, long time university engineering instructor, and one who got badly blindsided after I trusted the "best" small shop cyclone system to protect my health, I strongly recommend all small shop workers pay very serious attention to fine dust.
I am not too worried about explosion, a little concerned about fire, and a lot more concerned about building up dangerously unhealthy amounts of fine dust in our shops.
Starting in the early sixties insurance data and medical studies showed a strong causal relationship between airborne wood dust exposure and health problems with woodworkers.
Second, the high silica (glass) content in wood creates sharp jagged fine invisible wood dust particles that cause even more damage to our skin and respiratory tissues. Fortunately, the better air engineering firms share most of what they learned on the Internet covering what we need to do to capture the fine dust before it can escape. They did considerable experimenting and testing, followed by decades of refinement to establish the CFM requirements tables similar to the one linked from AAF that show what airflow measured in cubic feet per minute (CFM) we need to collect at each type and size of woodworking tool before it can escape.
Air engineers also came up with the formulas and tables to ensure we have the right ducting and blower. This engineering information shares most of the minimums we need for each type of dust collection. Air at the low pressures we use in dust collection, air is more like water, and does not compress.
Because air is near incompressible at the low pressures we use in dust collection, we end up with the pipe diameter controlling our air volume. Ducting Diameter affects the amount of airflow just like the size of the pipe and water valve size affects water flow. For instance a 1.5 hp dust collector that can move a maximum of 1100 CFM moves far less air than that maximum depending upon what sized ducting we use.
Ducting layout is not that difficult, but the details must be done right to ensure a good working system. A good working system must move the amounts of air we want for good collection and ensure the air speed in the ducts keeps the dust entrained, meaning kept airborne in both the mains and the down drops.
Unlike big industrial sites, most hobbyists should run the same sized ducting, fittings and hose right up to their machines. The next most important aspect of building a good ducting system is which type of ducting material you will use.
Although I am a fan of and personally use the higher end steel snap lock type ducting that is very pricey, I started off using HVAC pipe which worked well, then shifted to use of the thinner PVC pipe that is readily available in my area due to all the agricultural irrigation. There are lots of ducting choices and often we slip into a mode where we think if something costs less it is not as good. It is best to buy your dust collection pipe, fittings and flex hose from either a firm with free shipping or from a local supplier, otherwise you can easily pay nearly as much for shipping as for the cost of the ducting. Making your dust collection connections can be done with glue, screws, special duct sealant, and many other things, but most find that slipping all together works best. Although most prefer to hang their ducting from the ceiling, there are also lots of ways to put your dust collection pipe under your floor. For those who have a shop that sits on a heavy subfloor, it can be very convenient to run your ducting under the floor. There are many nice accessories that you can use with your dust collection, but realize that even with these accessories a dust collection system does some functions poorly. My first accessory mistake was buying a transition that mated my 4" dust collection hoses to the tiny 1.25" port on my band saw.
My dust collector came with an upper and lower filter bag that worked poorly and required constant emptying because I made lots of dust from preparing rough stock.
My next mistake was replacing the dust collector bags with an easy to empty lower plastic bag and fine oversized fine upper filter bag.
The Jerom Bos Multi X Dust origin Kit is an add-on junk wood dust extraction systems uk ingathering attachment for the Bosch line of MX30E Oscillating Multi Tools e.g. This page shares what the experts who guarantee customer air quality advise us to do to fix our tools, tool hoods, tool ports, ducting, and ducting layout to provide good fine dust collection. That is why I think all dust collection equipment should be placed or at least vented outside. Most small shops trap the fine dust inside where it builds to such high levels that a typical small shop woodworker gets more fine dust exposure in a few hours of woodworking than a commercial worker receives in months of full time work.
Medical studies and insurance records already showed most workers in OSHA compliant facilities eventually developed dust related medical problems. They established in tables like the Cincinnati Fan Engineering Data the air speeds measured in feet per minute (FPM) we need to collect various sized chips and transport those chips through ducting without plugging or building up dust piles. They also found these CFM tables are worthless unless we also modify our older tool designs that spray fine dust all over with better hoods, ports, and internal ducting to protect, control, and deliver the fine dust for collection as it is made.
They came up with simple formulas and approaches to help design our ducting to move the needed air with ample volume and speed at each tool. Roughly 350 CFM proved ample air volume to do good "chip collection at most of our larger small shop stationary tools and dustier operations.
This typical small shop dust collector blower only generates 4" to 6" of pressure when working. We constantly trade off our ducting size to move the right air volume at ample speed with minimum resistance. A leak between the collection barrel and cyclone will quickly clog your filters just like when the barrel gets too full killing any ability to collect the dust.
It takes very little airflow to move really fine dust, yet we need far more airflow to capture that same fine dust than we need to pick up the same dust we get with a broom. Unfortunately, most of the popular woodworking sites, dust collection vendors, and even dust collection books recommend large shop traditional graduated ducting designs that will not work safely with typical small shop dust collectors and cyclone systems.
At dust collection pressures air is more like water and will barely compress at all so any restriction or smaller duct acts like a water valve and kills our flow. If your ducting is too small, then it instead of your blower defines the CFM that your system can provide at your machines to pick up the dust.


Just about all HVAC supply stores and ducting supply firms offer one or more of these types of systems. It moved less air than my dust collector, just about half of what the vendor claimed in the advertising. 913.76 Lets piss a really fantastically effective dust extractor one that is whisper I americium not sure as shooting we can take for granted woodwind instrument compactness is thusly homogeneous only you are. Dust mastery shouldn't be an afterthought when it can save you time increase the Wood Whisperer Discusses Benefits of Dust Additionally ok dusts specially wood dust contain and carry toxic chemicals. HIRE A PROFESSIONAL ENGINEER to design, specify, test, and certify performance of any industrial dust collection system if you have a commercial or an industrial application, allergies, other medical problems, people working for you, a large shop, work with hazardous materials, or are subject to regulatory oversight. If you have not already read the earlier pages, I recommend you do so as good ducting is not required for good fine dust protection. We need about 350 cubic feet per minute (CFM) air volume with an airspeed of about 4000 feet per minute (FPM) to pick up and transport the dust and lighter chips. Woodworking shops located in commercial buildings subject to fire marshal inspection must comply with local codes which mostly follow the National Fire Protection Association (NFPA) recommendations. Every fine dust exposure causes some measurable loss of respiratory function, some of this loss becomes permanent, and continued exposure over time builds debilitating health problems.
The Australian Ministry of Health says this exposure level eventually leaves all ill with roughly one in fourteen forced into an early medical retirement due to dust related health problems. Plugging and dust piles pose a potential fire hazard and when these piles break loose over time they will destroy blower impellers, bearings and filters.
They built static calculators like the one linked here that estimate the resistance created by our ducting, flex hose, duct fittings, hoods, filters, cyclones, separators, etc. With the added overhead of our filter and minimum ducting, that pressure is only ample to move about 800 CFM when hooked up with a short piece of 6" flex hose. Likewise, many small leaks in the ducting quickly add up to the equivalent of having an extra open blast gate that will severely cut the airflow at your machines killing performance and potentially leading to plugged ducting. Although we all enjoy having bragging rights and a shop full of all different sizes of ducting looks incredible, for these impressive looking ducting designs to work in our small shops we would need monster sized blowers able to collect from all our tools working at the same time. This means duct sizes must be much larger for a good fine dust collection system because these systems must move lots more air. If you have this kind of set up, you should never clean your shop floor or other areas that might have metal or stone bits with your dust collector.
If your ducting is too large you might not maintain the airspeed needed to keep sawdust and chips from building up and blocking your ducting. The smaller pipe will kill the airflow needed to keep the air in the mains moving fast enough to avoid plugging and building up dust piles. I suspect most of my pipe and fittings would come from one of the large box stores with my wyes and longer radius bends coming from a local ducting supplier.
The next best is smooth walled laser welded steel pipe followed by a tossup between top quality metal spiral dust collection ducting and fittings and HVAC metal ducting, followed at a far distance by corrugated metal pipe and flex hose. Also notice that in spite of some vendor claims, these values show that PVC moves more air with less friction than even equal sized spiral ducting. Both of my two larger shops had nice sub floors and I ran most of the ducting under those floors. Those cracks made for a moisture problem that was not compatible with my galvanized ducting. Every filter cleaning left me and my shop covered in the fine dust I bought that fine bag to avoid.
That cyclone killed the airflow below about 450 CFM, plus did not move enough air to keep the ducting clear. Top Rated Products Swiss based reverse lightning has been producing quality tools and machinery for woodworking since 1958 and has earned a well deserved reputation for. Extraction Accessories break off Extractors amercement Dust Extractors vacuum-clean Extractors Power Tool Extractors metallic Ducting Workshop Air. With most of these facilities already blowing their fine dust away outside facility owners complained strongly against the proposed OSHA standards saying the new requirements were unnecessary and cost prohibitive.
In spite of badly inflated advertizing claims where many vendors claim their dust collectors have over triple this airflow, only two of the best performing 1.5 hp dust collectors actually provide 350 CFM in real use when connected to standard 4" diameter ducts and tool ports. The medical insurance data show roughly one in eight woodworkers who work in facilities that vent outside develop such serious wood dust health problems that they are forced into early retirement. In fact, fine dust known by researchers as particle material (PM) is so extensively studied that a Google search on "PM health risks" will turn up over forty-seven million references.
Roughly one third of all woodworkers eventually develop some allergic reaction to wood dust and about seven in thousand develop such strong allergies they must stop woodworking. They found fine dust spreads so rapidly even a big air cleaner or exhaust fan needs hours to bring the dust level down enough to be safe. The American Conference of Industrial Hygienists (ACGIH) responded recommending five times lower airborne dust levels and these recommendations were supported by the Environmental Protection Agency (EPA).
This also means our tapered and smaller adapters from our ducting to our tools are all but useless because they also kill our needed airflow.
To support the minimum 800 CFM we need for fine dust collection, we need to upgrade those 4" port connections to 6" and the ducting inside our machines to 6". Typical dust collection blowers need 7" diameter duct and 7" diameter down drops that split into tool hoods that equal about the same as a 7" diameter circle. This also means with our dust collectors and cyclones only able to collect from one tool at a time, we must design our ducting with all the down drops the same size and horizontal mains of that same size or at most one size larger. Also, most "official" dust collection pipe uses proprietary connectors and sizes that often limit your expansion to working with just that firm. The low cost S&D PVC (plastic) pipe (see my PVC site if you want to do "magic" with fitting PVC into your ducting.) is generally one of the best small shop dust collection material choices because it is smooth, far stronger than most HVAC metal pipe or spiral pipe, costs less, and fittings are a fraction of the price. The rule is never hook a dust collector or cyclone to any size pipe less than 3" in diameter. I later learned during the medical air quality testing done on my shop that my so called filter was a sieve that freely passed most of the finest unhealthiest invisible dust. Studies commissioned by facility owners appeared that make many false claims such as woodworking makes no fine dust, venting outside blows the fine unhealthy away, there are no health risks from wood dust, and because commercial facilities vent outside their workers receive almost no fine dust exposure. For instance one popular cyclone vendor who sells ducting designs and parts strongly puts down the use of PVC duct because it does not meet NFPA standards. They also formalized this process into something that most can follow without special training or expertise to come up with a good dust collection system. Likewise, if we use bigger pipe, we then have to use a bigger blower to keep the airspeed up enough to avoid our pipes plugging and building up dust piles.
Good fine dust collection requires 1000 CFM which requires 7" diameter ducting or using a bigger more powerful blower that generates the pressure to pull more air through a 6" duct. At the machine the down drop duct may split into two collection pipes for two collection points so long as the overall cross sectional area is the same or only slightly larger than the down drop, but otherwise our ducting remains very simple.


On that same 4" ducting a 1 HP unit that gives 650 CFM maximum rarely will maintain 350 CFM.
It pulled the real 1100 CFM I got from my dust collector through a 6" test pipe to under 450 CFM.
Fine airborne dust spreads so quickly that good air quality requires collecting the fine dust at the source as it is made before it can spread.
Although that upgrade helps, wood dust has since been classified as a cancer causing agent so medical experts recommended a fifty times higher than OSHA air quality standard which has already been adopted by the European Union. We need the same airspeed to pick up the chips as we do to keep it moving in vertical ducting runs, so collection and vertical transport speed are often interchanged. Since we use the same size and types of tools as smaller commercial tools, most of what we need to do for good fine dust collection is already laid out in detail. Unfortunately the 350 CFM needed for good "chip collection" falls far short of the airflow needed for good fine dust collection. If made too large it does not maintain the airspeed in the ducting to avoid plugging and a buildup of dust piles. This is why we must move so much air to pull in dust from all around the working areas of our tools. With just one ducting run at a time open, we need much simpler ducting designs than the commonly recommended graduated ducting designs that collect from all tools working at the same time. Additionally, duct itself adds resistance that can also seriously hurt our flows, so a good ducting design uses all the right sized ducting components and provides the shortest straightest runs possible with minimal sharp bends or joints. That makes the dust more awkward to empty, but safer and the metal flex duct is much less expensive. Likewise, HVAC metal ducting thickness and size can vary considerably, but most recommend getting at least 26 gauge pipe.
You can put in your ducting, power, water, and whatever else you need or want to run under that floor, then have easy access to make changes. We can get by with a little less airspeed to keep the dust moving in horizontal runs because horizontal runs do not have gravity working against us.
Each of us can go through this process to determine our needs, pick a blower large and strong enough, configure our ducting, separate off the heavier dust, and either exhaust the fine stuff outside or appropriately filter that dust.
To get our 1000 CFM that larger tools need for good fine dust collection through a 6" duct or hose we need about 5,100 FPM and that takes at least a 15" diameter impeller when turned by a standard 3450 RPM direct drive motor.
Any fine dust that does not get trapped by the dust hood gets launched by almost any airflow from our tools, belts, cutters, motors, etc. Between use of the very inefficient flex hose, too small of a diameter pipe, and too many sharp angled fittings in their ducting, most hobbyist woodworkers severely kill the potential airflow needed for good dust collection. These piles and plugs pose a serious hazard as any spark can quickly get blown into a ducting fire.
If your dust collection system is properly sized it can go anywhere in your shop, but most use smaller dust collectors and cyclones, so these should be placed as closes as possible to your tools that require the most CFM for good dust collection. Even reducing ducting size right at the machine for the shortest possible distance to a small 4" port will still kill system performance. Most "snap lock" ducting in the larger home centers comes in light 30-gauge or heavier 26 gauge galvanized steel.
Also, most small shops never create the right mix of airborne dust to create an explosion, and our systems do not generate enough static to ignite an explosion.
These firms found the most existing tools came with no dust collection or at best poor "chip collection" built in, so worked poorly for good fine dust collection. Instead of just having to cover a 4" diameter area they found for good fine dust collection our hoods needed to cover roughly an 18" diameter collection area. Without an oversized blower, if your duct is smaller than 7" to your larger machines, then it will not move enough air to capture the fine, most unhealthy dust. The only way to prevent this is to have good hoods that keep the fine dust controlled and move enough volume of air to capture it before it gets launched. The smaller ducting, flex hose, and small ports limit the maximum airflow just like we proved in that little air test sucking experiment! Do not use a dust collector as a vacuum because any steel screw or nail picked up hits the impeller and can put a spark in the collection bin. This same vendor then justifies their sale of cyclones that fail to comply with the NFPA rule that all indoor cyclones must be fire and explosion proof because there has never been a reported incident of a small shop dust triggered explosion. With costs to replace existing tools prohibitive, air engineers found they could get good fine dust collection at most older tools by moving enough air and upgrading tool hoods to better contain, control, and deliver the fine dust for collection.
The same simple ducting formula feeing in our 50 FPM needed to collect the fine dust over that 18" sphere shows we need.
Bumping up to 6" pipe causes problems for the under 1.5 HP units because the air speed (FPM) can fall too far and make dust block the pipes, but with this bigger pipe, the bigger units end up going to 800 and 900 CFM. Also, most dust collectors make poor vacuums because the airspeed is too low for good pick up. Strangely, this same vendor totally ignores the NFPA guidelines and sells cardboard dust bins that are a bad fire risk, plus they only use aluminum impellers that the NFPA abandoned years ago. They developed new CFM requirement tables for each size and type of tool that with hood upgrades moved enough air to ensure capturing the fine dust. Air engineers established most woodworking operations that do not make heavy big chips are well covered if they target their blowers and ducting to move 4000 FPM airspeed. That's why knowledgeable woodworkers use oversized blowers and 6" ducts and 6" flex or 7" ducts and 7" flex when using most cyclones and dust collectors.
They found the only effective way to get good airborne dust control at each tool source is to upgrade tool hoods to contain and control the fine dust, upgrade tool ports to not restrict airflow, move far more air to ensure collecting over a large area to capture the fine dust before it can escape, use larger diameter ducting able to carry ample airflow, separate off the heavier sawdust and chips, then get rid of the fine dust. As with water, getting a bigger blower with more horsepower does little good if the airflow is too restricted by the size of the ducting, tool ports, hoods, and duct openings.
Unfortunately, the more air a blower pushes the higher the amp draw, so if you open things up too much with a dust collector smaller than 3 hp or cyclone smaller than 5 hp with a cyclone you can burn up your motors. The same formulas show we need to use 7" diameter ducting to move the air for both the ACGIH and medical standards already adopted in Europe. Unfortunately, many alternative ducting materials are flammable so are totally inappropriate for use anywhere except in plain sight.
If we use too small of ports, duct, fittings, or outlets, we kill the airflow needed for fine dust collection. In 1989 when OSHA finally declared wood dust a nuisance and set air quality standards, most large commercial shops were already running OSHA compliant dust collection.



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