Hey CalgaryD,
strange idea. Why use many shop vacs if you get a dust collection system with an induction motor at Harbour Freight for $299. Okay you’ll have to add the cartridge filter to get an acceptable wood dust filtering.
Shop vacs that run permanently like when used in a CNC will make replacing carbon brushes within less than a year.
Hey Martyn,
this person owns a Jet dust collection system with an induction motor and a big cyclone separator that looks a bit like the Axminster AW118CE, but now replaces it with a Felder AF 22
The Felder AF22 Dust Extractor - Could this be the best value Dust Extractor on the market – Youtube
I will buy this one too. It’s made in Austria and the motors are made in Italy. What I like is how easy it is to change the chip bags during operation, and the choice of different motors.
Another video:
Simple. If you cannot or do not want a dust collection system. It is also much more portable, and you can add / remove vacs, if you need to. Also, this may be a solution, one of many.
Personally, I like it because it provides much more suction power. Dust collectors move a lot of air, but only if the air resistance in the system is low. The pressure drop they create is lower than the pressure drop of a shopvac. Thus, if you have resistance in your collection system, such as 2.5 inch ducts, shopvac may even provide more air flow at the collection point than a dust collector.
I am not saying, that a dust collector is bad, simply an option.
My shopvacs, all of them, have HEPA filters installed. The dust collector you pointed out protects the machines, not your lungs. Can you have a HEPA filter for it? How much would this add to the price?
Hey CalgaryD,
Regarding the Felder AF 22, you have seen in the link and in the videos that they have a big filter cartridge. They have dust class “M” which corresponds to what you call “HEPA” in the USA.
Regarding the Harbour Freight, I have seen many people that added a filter cartridge of “HEPA” class. I don’t know the price but a WWW search engine may answer this.
You consider a Onefinity CNC as “portable”? Okay, I forgot that they also sell a model on wheels. I did not have that in mind.
But like all air suction devices, the more air flow rate and capability you have, the more the air flow remains at a high level and does not drop, even if you have foreign air drawn. On a CNC that mills wood, that is a frequent situation, as often it is difficult or even impossible to have the dust boot fit the workpiece perfectly. Often you can’t avoid that foreign air is drawn there. And a dust collection system will not have the air flow reduced then, so it may be that despite producing less pressure, it will draw the wood dust better as a shop vac.
Just throwing my findings into this:
As @Aiph5u can attest, I have been going through my own dust collection trials and tribulations.
I hope the following breaks it down in simple terms that took me a few months and dollars to get drilled into my head.
When it comes to workshop dust removal, there are TWO types of vacuum systems.
High Pressure, Low Volume (HPLV) which are your Shop Vacs, and more officially referred to in the industry as “Dust EXTRACTORS”. Screamingly high pitched, noise demons that rely upon SMALL hose diameters (2.5") but extremely high pressures to move things around.
Low Pressure, High Volume (LPHV) systems which are the “Dust COLLECTORS” like the 1HP, 2HP brushless inductive vacuum motors that use 4" hoses to move a lot of VOLUME (large diameter hoses) but at very low pressures.
My biggest mistake was to purchase a (Harbor Frieght) 1HP dust COLLECTOR and then drop the hose diameter down to 2.5". This caused an absolute collapse in performance and made it almost worthless to use the dust collector this way.
Watch this video to see the differences, and what exactly why this is the case:
Take away: if you have a 4" dust collector, you need to carry the 4" hose all the way to the tool, such as a band saw or table saw that has a 4" outlet built-in from the manufacturer. If you have a tool (i.e. Onefinity dust boot) that only offers a 2" dust hose port, then only use a 2" dust extractor.
Note, there is one main manufacturer of dust collectors, the name of which escapes me, that actually offers BOTH 4" and 2" hose ports and uses TWO different motors inside for each of them; a HPLV motor for the 2" and a sepeate HVLP motor for the 4" outlets.
Hey Forrest,
why do you all think that more pressure is an advantage? It isn’t.
If you consider this:
Also one difference between both systems is that usually dust collection systems have a motor with much better efficiency and more power.
Maybe the problem with your Harbour freight 2 hp is that its motor is only capable to deliver 1.5 kW. On the Felder AF 22 you can select between 3 and 4 kW.
EDIT: I just saw you didn’t buy the HF 2 hp, but the 1 hp! Okay that is possibly an ever bigger mistake.
If you buy a CNC, you’ll have think that it is necessary to have a dust collection system that will draw all the dust. You should not save on this. It is true that a dust collection system may consume more electricity than the CNC itself, depending on the spindle power, especially because the dust collector runs all the time.
An advantage if you select a three-phase motor for your dust collection system as Felder offers, you can attach it to a VFD and slow it down.
Sorry, I didn’t mean to infer this, all I wanted to make clear is that there are two types of systems, both of which work as long as you use them as intended. My Dewalt SteathSonic shop vac performs just fine, as well as my 4" Harbor Freight dust collector performs perfectly, as long as I don’t try to use a 2.5" hose on the 4" HF dust collector, or use a 4" hose on the Dewalt.
A shopvac doesn’t necessarily provide more air flow than a dust collector, it just does it at quicker air speeds, and in other words, at higher pressures. Because as the speed of air or a fluid increases so does its pressure.
Similar to spray paint systems, there are HPLV systems, and HVLP systems. At the end of the day, both push material through a nozzel and onto a surface.
My 4" dust collector system will move a LOT of material in the same way my 2.5" shp vac will. They just do it differently and trying to expect a shopvac to work through a 4" hose or vice versa is likely to fail.
It is, if you collection system has high resistance, such as, for example, 2.5 inch piping. Which I have. You can totally use the analogy:
pressure is voltage, resistance is resistance, air flow is the current, then. Dust collector is a battery of low voltage and low internal resistance, shopvac is a a battery of high voltage with high internal resistance. This explains everything.
The air flow does not happen magically, air flow is generated by the pressure difference between two points in the circuit. Shop vac can generate airflow where a dust collector cannot, but it has its own internal limits and cannot move more air than what it has in its specs.
This is all very consistent with what Forrest was saying. Totally agree with his post.
yes, and as with electricity, what matters is the current. Dust collector = high current, shop vac = low current.
Everything you wanted yo know (and a lot more) about dust collection.
Been using this blower for about 3 or 4 years with excellent results, pulling through a 12 gallon oil drum set up as a dust collector.
https://www.amazon.ca/gp/product/B07L9G49VY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
It came with a dust bag, which I do not use as I can drop anything that gets through the oil drum on the ground. mine is outside the workshop and is fed via 2.5 inch flex tube linked to main line 3 inch PVC piping, using fittings cobbled together out of 3" pipe caps. Instead of blast gates, I simply pull the modified pipe cap off and put a pipe cap onto the 3" pipe or Y to close that branch of the dust pipe. I see no reason to upgrade this as it has served me well for years. Biggest hassle is emptying the drum.
Less than $500 cost and probably less than 8 hours to install, works for my miter saw, rigid oscillating sander, planer, tablesaw, CNC, bandsaw and with a piece of 2" pvc pipe with a brush on its end works as a vacuum cleaner on the shop floor.
Hey Tony,
and does it catch all the dust on the Onefinity?
In combination with which dust boot?
That’s what I like on the Felder AF 22: How easy it is to change one of the chip bags during operation, and the choice of different motors. You simply have no contact with the wood dust. See the video of this happy user changing the dust bag:
The thought of having to pour out an oil can full of wood dust somewhere seems horrible to me. Okay, you can put a plastic bag into the oil can too, but on the Felder AF 22, the dust bag is in no can, and it can be changed extremely quickly. And you can do it during operation, because it has two bags that can be selected for use.
Another video:
The Felder AF22 Dust Extractor - Could this be the best value Dust Extractor on the market – Youtube
In this video this user replaces his big JET cyclonic dust separator by a Felder AF 22. The JET required all unused air valves to be closed except the one that he would work on. When he switched power on on the Felder AF 22 for the first time, he had a lot of air valves open, and nonetheless the Felder drew a lot of old chips and wood dust from the system and from the connected machines that the JET had never catched!
I have also researched the dust issue, personally, by actually reading scientific papers. This link provides misleading and over-dramatic view of the issue. I would not recommend making decisions on dust collection based on the information from that site.
According the the Report on Carcinogens from 2000, there is a correlation between exposure to wood dust and nasal cancers. It is not causation, but correlation. The dust that ends up in the nasal cavity is >10 um in size. This is the real issue. However, the relative danger of exposure is difficult to evaluate, on quantitative level. Anyhow, the fine wood dust that is <10 um, therefore is not a carcinogen.
I do have a dust monitor in my home. I cannot confirm that dust can stay for years in the air. It settles down quite fast, even without active filtering. Yes, you can lift it up again, if you disturb the surfaces it is on, but it will not fly indefinitely in the air. Lots of information on that web site is either incorrect of somehow misleading. Not surprisingly, the amount of references they provide is really minimal. FYI.
As a physician I can say several of the conclusion you state are wrong.
Using a year 2000 document for reference is ancient history in the medical world. For example the 2021 version of the document you reference says wood dust was classified as a carcinogen in 2002.
While association is not causation, finding association in a medical study doesn’t necessarily rule out or disprove causation. Your making an assumption there.
Flatly stating fine wood dust doesn’t cause cancer hasn’t been proven. Finer dust settles down in the alveoli - not the nose. It potentially can be a danger there.
Your focus is solely on cancer. Pulmonary disease related to occupational exposure is a huge category. Not just cancer. COPD, pulmonary fibrosis, pneumonitis, etc can all be devastating.
This is a complex problem with conflicting research that isn’t as easily boiled down to what you stated.
OK, I have no objections to your corrections. Good, I am grateful for your comments. They are helpful. However, I wanted to point out that there is a lot of speculations in the wood dust question.
I do agree that working with wood can cause various problems. They, however, may not be that dangerous and may not be even caused by dust. So, just stating “wood dust is a carcinogen you must filter 100% of it out”, may be oversimplified exaggeration. This is why I concentrated on the most problematic side.
Yes, I personally had a problem when I was working with red cedar. Bad allergy. However, a P100 mask did not help at all. So… the problem, as I am guessing, was caused not by the dust, but vapors from the sap and oils from cedar, not the dust.
Thus, I think, we should understand the issue fully, without panic, and only then try to find a good solution for it. Most of the dust collectors, for example, only offer 2 micron filtration with quite low pressure drop. What is going to happen if you add a good HEPA filter? Will the air flow drop? By how much? Why do the not sell it with the HEPA filter right away?
I found an Oneida Mini-Gorilla dust collector, but they are quite expensive. So… as a physician, what would you suggest in regard with the wood dust in a home workshop?
Well, no, I am not making an assumption here. I am stressing that correlation does not mean causation. This is totally true. I am not saying that there is no causation, I am saying that it was not proven.
I appreciate that response. I agree with pretty much everything you said. As I pointed out it is a difficult problem with no simple answers.
I would advise each person look at their individual situation. You should take into account your personal health risk, your risk tolerance, your style of work and your financial situation. I’d get the best system I could afford that fits the type of work I was doing. If I had a long smoking history, morbid obesity asthma etc then I would certainly spend more to get a system that cleans the air. If I’m running a business going through a high volume of wood I’d spend more. A hobbiest such as myself in my garage gets a lot less exposure than someone running a business who really churns through a ton of wood and is constantly exposed. If you’re working other materials you may need even more specialized equipment. For example metal dust is potentially explosive. Those working lots of metal are usually advised to get sparkless vacuum systems.
Dust collection is a rabbit hole you can fall into pretty deep. Go ask Bill Penz.
Oneida makes a good product I believe but you definitely pay extra for it. There are other options to upgrade current dust collectors if you have one already. Oneida and Wynn environmental have aftermarket filter canisters of different filtering capabilities if you want to go that route. You could tailor it to what your dust collector would allow based on airflow.
There are many calculators out there that can tell you what your various tools require and calculate the static pressure drops of your ducting. I’d check woodworking websites and forums not just cnc websites. Dust collection is a huge topic on those websites.
Personally, I did the best estimate I could have my dust collectors air flow. I got an anemometer off Amazon and calculated my cfm/airspeed. I upgraded my filter media through Oneida after that. I reconstructed my jet 1.5hp jet dust collector to a two stage collector with Hepa grade filters. Was way way cheaper than a dust gorilla. If I’m doing something really dusty like sanding I add a dust mask but usually not for basic table saw /router stuff.
Despite Bill Penz being alarmist he has a simple air cleaner you can build on his website. I chose that over the air filters you hang from the ceiling. It moves a lot of air and gets a lot of dust.
My system was a compromise but it is the best I can do with what resources I have available for the style of work I do. Otherwise like everything in life you do the best you can.
One last comment. My personal belief is that you should get a tool designed to do the job your asking of it. If a vacuum isn’t designed to be a dust collector I don’t think you should use it that way. Get a proper dust collection system. Cheap 2hp harbor freight dust collectors aren’t that expensive. Replace the filter and you’re good to go. But that part is only my opinion. (A bit hypocritical coming from a guy who uses a makita router instead of a spindle. )
My issue with using a dust collector is the noise. I take my 4" hose down to a 2.5" and it does a fine job of collecting the debris from my CNC. However, running that noisy beast for 6 hours kinda sucks. If I can get similar performance from a quiet Fein shop vac, that becomes an attractive option.
I didn’t read every response, but I didn’t see anyone mention Oneida.