I built the 8 filter version with the 2500 cfm fan for our non-profit Made4Me shop and it has made a significant difference to the air quality. We build adaptive furniture for handicapped kids using cardboard, which leaves very fine dust in the air when cut. Thanks for your work here!
Have you tested dust performance with an air quality tester between push / pull configs? I've read a few articles that having the air purifier blowing air straight up and sucking from the bottom provides an increase in performance. Since CFM isn't a qualifier of how much is being filtered.
Yes I have but the video isn't out yet. If you are close to the filter and the dust gets pulled right in, that increases the efficiency of the unit. If the dust source is far away and the filter is just processing ambient air, the pull config works much better. I'll do a video on this concept some time soon. Thanks for the comment! Sorry for the late reply, it's been a busy month.
I sure am. The wait time is a bit long at the moment but that is improving all the time. Let me know if you have any questions! www.etsy.com/shop/The3DHandyman
Thanks for noticing! I'm trying to be as scientific as possible on a budget. The rigs aren't perfect but they are good for side by side comparisons. ...maybe I'll have CGP Grey's subscriber numbers on day. Hah
Lol I didn’t realize I was a nerd until it just hit me that I’m watching these videos while doing dishes and ONLY listening to the audio. You’re doing an incredible service for DIY peeps at home. Thank you so much man. ❤
Dude! How am I just discovering you! You are a real builder, well spoken, and your graphics make it soooo much easier to understand how it goes together. Thanks!!!
This is a great DIY build! I built and have been using mine with the original orange fan for quite awhile now and can attest to its function. With some mods to the original plan, it is now even better. With an added filter on top of the fan to keep dust out of the motor, and a longer power cord/external switch, this unit keeps my small garage shop free of airborne dust. I have ordered the Cat black fan to upgrade the power of my unit. No more hacking cough after a day making sawdust. Thanks again 3D Handyman for putting this plan out for all to use.
Thanks for the great idea and plans, you are a gift. I built one of these with 3/4 MDF, had to make a few adjustments to the plans to make it work, but it does. And for kicks, I combined it with a modified version of this build (th-cam.com/video/ccPqfBEu5PI/w-d-xo.html). Tweaked the code to avoid the fan cycling on and off around the threshold point and added in a 8 by 8 LED matrix panel to show me at a distance what the air quality was at. Green for good, yellow for 'starting to get punky in here', and red for 'mask up'
It's crazy how people come up with the same ideas all the time, I've done this on my intake for my old greenhouse i built in the basement. 2 box fans listed at 2200 CFM and 3 filters plus 2 more fans for the exhaust with another 4 inch filter to catch pollen. Works great, i should've gotten these bigger fans though cause these things kick ass
Sounds pretty cool. I got into vertical farming for a while. Our space definitely needed what you built! These drum fans are great for all sorts of uses. I also found a fan that might be a possible upgrade for your system. It comes with it's own fan shroud like the drum fan www.lowes.com/pd/Utilitech-Pro-20-in-3-Speed-Indoor-Air-Mover-Fan/1000018619
A box fan has a fractional HP motor. Generally around 1/25 hp to 1/32hp. It's merely designed to move air, not draw it through static pressure. A furnace blower on a 3 ton air handling unit employs a centrifugal fan with a 3/4hp motor. And it's rated to between 900-1300 cfm. I can provide the tables from the manufacturer upon your request. Design of blades, and housing matters here. A fan meant to just push air with 0 static pressure and 0 resistance can use propeller blades. Exhaust fans get away with them because often the air they are moving is hot (think kitchens) and hot air naturally rises. So the fan is actually just directing it out a vent. Same principles with a chimney on a wood stove. You get good draw when the fire generates enough heat to start pushing up through the chimney. Until that point the fire can actually smother. Air becomes denser (and heavier) when cold. Humidity also affects characteristics of air. All these things will change your fan's performance. Try placing the Corsi Rosenthal Box filters in the tunnel and have the fan pointed into open air. Place your anemometer anywhere in the tunnel and check wind speed velocity. In all air filtration systems emphasis should be on draw rate. Nobody cares about exhaust rate because that's filtered air. Measure draw rate. Impelling dust into your box (pusher configuration) your anemometer will have a high velocity because it has 0 resistance. On the other hand your math equation won't have the huge surface area, but that's how the math has to be done. The design of the CR Box pulls air through filters, and thus resistance to flow becomes a factor. So you measure air flow drawn through the filters. I have personally put a lit tea candle inside my CR Box. The air flow through the filters did not snuff the candle out. Made me scratch my head and realize the purported math was wrong. If you put a tea candle next to your AC's return duct it will snuff the candle out. A centrifugal fan is specifically designed to work when resistance and pressures exist. It also is designed to create a low pressure environment inside the return ducts. Further inducing house air to enter and go to your furnace, and A-coil. www.ccohs.ca/oshanswers/prevention/ventilation/fans.html GREAT JOB! I love your curiosity and willingness to investigate. You've the mind of a real scientist and critical thinker.
It seems like the intake and exhaust air flows must be identical right? Once the unit is running for a set amount of time the internal turbulence dies down and a stable air column forms. There may be some level of static pressure after that point inside the filter box but that number must be a constant, not increasing with time. I'm no mathematician but it seems to me that there can not be more air entering or exiting the device. The numbers must be the same? A thought on the candle experiment... maybe the air moving through he filters is just doing so in a less concentrated state. There is a lot more area for the air speed to diffuse through the filters. The filter material also likely produces a column of air that is smooth and lacking in turbulence. If the candle is in the center of the CR box bottom then air will move in equally from all sides and the velocity of the air in the center of the box may be near zero as the air comes in equally from all sides. This may only apply when the fan is in the up position with 4 filters on the sides. Just a thought! You are right about centrifugal and inline fans being better for high static pressure applications. The standard CR design does appear to be somewhat restrictive. If the design instead uses 20x30in filters the 4 filter design is actually able to hit no zero static pressure on the filters with 3M MERV 13s and an Air King box fan. The wooden kit that I tested them on does create a 15% loss in airflow vs the box fan without filters or a kit. A blower like this ( www.grainger.com/product/DAYTON-OEM-Blower-Rectangular-1TDU2 ) would be less affected by is restriction than the box fan, however it's maximum capacity is 1200cfm and that is also the output of the Air King. When the Air King box fan is $50 and the blower is $340, the best value is quite clear. I'll be testing a popular ceiling mounted design at some point and I think the issues you talked about with the shape of the fan blades will be more apparent due to how shallow the filter box is. I also have a design for a centrifugal fan powered filter but that video is a little ways off. Thanks for the opportunity for some critical thinking! I am still working on the script for the next air filter video and it helps a lot.
I'm a little curious why you wouldn't flip the fan over to pull air through all the filters rather than blowing into the filters? Just seems like you'd get more air filtered by sucking air from the whole box.
That is true in some cases but not all. I'll talk about it a bit in an upcoming video and get into more detail in a video completely devoted to the subject. It is a question that people ask a lot.
It does and with 3M MERV 13 or 14 filters it is also significantly more effective than the Donaldson. The Donaldson acts more like a MERV 11 in my tests, not as good as the Wynn of the same size but definitely more reasonably priced.
Great stuff! This series of yourinspired me to rebuild my single-filter, box fan version. I love everything about what you've done here: good methodology converts specs into the real world. Thank you.
I was wondering if an air filter like the one you made is good for just oulling natural dust out of the air in our shop. Is it something you need to run all of the time or just occasionally?
I tend to only run it when I am making dust. Some people have put them on timers to that they run for an hour or so after they stop working to capture any remaining dust after they shut things down for the night. You could also keep it running on a lower speed if you are trying to keep the air free of dust if you have paint drying or something like that. It's really up to you
Hi there - thanks for the great videos on air filtration! I am thinking of building your design for the "Compact - 1700CFM Ceiling Mounted". Is the intention of this for the fan to be blowing inward (up) or outward (down)? Thanks again!
Really bad idea because First your motor should be a centrifugal motor for high rate static pressure. You talk lime a guy who knows about CFM but we don't really care it when in fact its more about STATIC PRESSURE. Plus, your motor is placed in the wrong side. Your motor should be place at the exit, BEHIND your filter, otherwise your dust is going inside the parts of your motor...
I don't know how the algo got me here, but i'm glad it did. I have massive attic work that needs doing, and it's beyond disgustingly dusty up there, especially after just having my roof replaced. I started using a lasko fan with a cheap 1" filter, letting it get sucked on the inlet side. it helps, but I can see building something better and letting it feed for a couple hours while periodically hitting everything with a battery powered leaf blower, is going to make my life MUCH less of a living hell. So thanks for that, and for convincing me to spend money. :D
Any time! Haha. I actually cleaned up a similar space in just that same way. Kick the dust up with the leaf blower and let it get sucked up by the filter. Don't forget to wear a tight fitting mask 👍
Do the pc fan CR box filters really push the same CFM at a fraction of the energy consumption of a box fan CR filter? Some clean air kits claim 7-10 watts!! That would make it over 10x more efficient than the air king box fan on its lowest setting!! 😮 Definitely something I want to consider, since it’s much quieter at almost the same claimed given CFM, if that were true.
Thank you for objectively testing things. If I could block every channel which gives opinions without tests, I would. Instant subscribe from me. What brought me here is my interest in filters for VOCs with activated carbon--thinking of options for a cage for filter media which is cheap in bulk, but expensive in genuine replacement filters.
Thank you! I have some ideas for this and the video will be out in a few weeks. I'm going to use a large carbon canister for the test. I'll also pull the canister apart to see if I can easily replace the media to save $$$ in the long run. I will be switching to an inline fan for this because the axial fan in this video is not great for high static pressure loads that you get with lots of carbon.
Question: Do you have any data comparing the standard 1" thick filters with the 4 or 5" filters on the market? Impatiently waiting for the rest of the series! Really interested on what went into "Beastie Boy"!
@captainhook426 The thicker filters offer more filter surface area. A 4" filter might have several times more material than a 1" filter, but probably not 4 times more. I can add the data into the next video that can illustrate the concept a bit better. I hope that will be out next weekend. I just finished testing a large box fan with a 20x20x4" and the fan went from 1700cfm on its own down to about 550cfm with the filter installed. I'd like to build the Beastie Boy but I don't have a need or the $$$ to test it out yet. Hopefully someone will watch the video and order one so I can test it? We will see. Thanks for the comment!
At about the 6:50 timestamp, the question was raised about how to calculate the “open area” of a filter. The open area is the total surface area of the filter material, not of the filter cage, so to measure it remove the filter material from the cardboard cage and stretch it out on a flat surface to remove the pleats, then measure its area. The effective area is actually a bit lower than that due to obstructions like the plastic bands and because the airflow is not normal (perpendicular) to the filter material due to the pleats.
Why not feed the fan into a dust collection system instead of a box of filters? I'm looking at a collector with 2 x 100mm ports. One I could use for powertools and other connect to the fan. So it's blowing in and sucking at the same time. When the collector is off the fan just blows into the collector. I'm wondering if having one vent with extra blow will improve the vent connected to the tools because the collector output would be increased. Anyway, so I'm thinking why buy a collector and air filter when the collector with a fan could do both.
I do like that idea. I'm not sure how it would work in practice because airborne dust is generally extremely fine and it does not settle out of the air like dust that goes through a dust collector where some centrifugal movement will cause it to drop into a bucket. I generally run a dust collector at the power tool and then have the filter running in the background, it's not really a great replacement for a dust collector itself. The fan also cant handle chips or vacuum hose size tubing. The static pressure in this scenario is to high for the fan to function at an acceptable level. Impellers are better for dust collectors than axial fans. I can imagine a system that would make this a reality but it would probably be quite large!
@@The3DHandyman The filter on the collector won't last as long since it will now be holding the fine dust. As you say it won't drop into the drum. But is that any different than the fine dust within larger dust coming from the power tools. From the fan to a 100mm pipe/vent id imagine some cone shaped joining the two. Blowing down a pipe while also sucking from the other end might have some physics complications. I'm not an expert and just wondered why blows into a box with filters when most shops have a collector. If I'm buying the collector and a high velocity fan anyway. Might as well try it. Failing that I'll create a separate box and filters for the fan.
@@ProjectKelstone That's a awesome experiment. Let me know how it turns out. I may do a video on something like that one day. I have been working with prefilters for this designs and others that should help extend the life of the filters. Even without that, they seem to last about a year before they start to lose performance. I weighed a set of filters on the Model-A that I've been using as a dust bin for the last year and there was about 1400grams (~2 liters) of ultra fine dust on them. So, they can handle a lot and still keep going.
I picked up some laskos average price 20$ im wanting to order your kit C but got to thinking about a hack. What about adding feet and flipping on its side and put 2 laskos on opposite ends blowing outwards. ?
The fans would probably need a lot more Velcro and/or screws to hold them on in a horizontal configuration. I could send you (2) top pieces in place of the (1) top and (1) bottom. (4) 20" filters will probably not be enough to handle the amount of airflow that two box fans can produce. The B kit (20x30" filters) would be better in that respect. The 20x20in filters will probably be better off with just 1 fan. The edge of the unit is fairly narrow, so your foot options wont be extensive and you would have to custom mod something but there is no reason why this is setup wouldn't work. If you want one, just message me on Etsy or you can just order one at the regular price and I will ship you the custom version. Just be sure to add a Note at purchase about this conversation.
@@The3DHandyman I was thinking for a unit to hang from the rafters... I dont think blowing air out both ends would be good for use right next to a dust source. I did pick up a box of 12 airguard merv 13 20x20x2"(19.5x19.5x1.75) filters for 15$. does your kit C work with 19.5?
@@elkskiutah8204 Yes, the kits works with all filters roughly 20x20 in size. Many brands of filters fall into the .5" to small category. The kit will also fit 1.75in thick filters just fine. Be sure to leave a note at checkout about sending 2in filter clips with your order.
At the bottom of this page there is a link for "The original air filter" the3dhandyman.com/workshop-air-filter-series/ Let me know if there are any issues!
I do in this video th-cam.com/video/XAJ__E-hIJc/w-d-xo.html The version in this video will get tested in the next release. It manages to filter smoke out of the garage in under 30 minutes with 3M MEVR 13 filters.
This is great content, thanks for your work on it. I wonder if you've considered or tested cartridge cylinders matched with the Caterpillar fan? The Wynn 35B222NANO Cartridge Kit filter is more expensive but smaller, MERV 15, and 222 sq. ft of filter surface area means tons of capacity by my math. Very simple "assembly"... I saw this on the MMCC_Woodshop channel.
Great question! I actually got some canister filters to test with. They are very similar to WYNNs in their construction but not exactly the same. You can also get 2 for the price of 1 WYNN filter and they are still made in the US. As for the design of the filter in the MMCC channel... in general I think it works but it could work better. The hole in the top of a WYNN filter misses the outer edge of Caterpillar fan by about 1inch. The out edge happens to be where air is moving at the highest rate. So, the filter itself accidentally becomes an unwanted obstruction. My guess is that, despite the increase in filter surface area, the WYNN+CAT design may only be able to output about 750cfm with a brand new filter. It would be nice to know the exact number, but I bought a canister filter that isn't quite as wide as the one used in his video so without dropping another $300, I cant say for sure. For canister filters I think that inline fans are a better option because of how well they fit on the canister and how well they handle static pressure. I'll cover all the positive and negative sides of the design in an upcoming video. I'm also making a new kit and free download for my mods to this design. Those modifications do make assembly a bit more complex than the super simple method shown in the MMCC video but I hope to improve the long term performance for a similar price point.
I'll have a new video where I test inline fans on this sort of kit out soon. The one I use doesn't move as much air as this drum fan but it is still very effective when ducted. In some cases ducting the air makes it more effective even without the added cfm.
I was wondering about MERV ratings, and whether they are the total percentage they can remove over time, or for a single pass. It sounds like it’s the latter, but I struggled to find any good information on this. Do you have a source that talks about this specifically? Thanks so much for making these videos. Really an incredible resource.
Hello Sir, I don't have a shop to build one of these units. I'm wondering if you will build the frame and ship the necessary parts (excluding the fan) that I may assemble and use in the space I need it in? Thank you, John
Hello! I have made some changes to these kits in the last few months and now the same features of the design in this video is available in a slightly different package www.etsy.com/listing/1373712349 They temporary assembly video is available here while I work on the official version th-cam.com/video/MLF8qv1tGSQ/w-d-xo.html If you have any questions at all, let me know!
Where is the "Lies in the wind" video discussed at 46 seconds? My AC ceiling return pulls most of its air through the center of the filter, which wastes most filter material. I am wondering if a plenum (box) above the grill and filter would better distribute the intake air over the entire filter.
I have a whole series coming out in a month or two. I probably wont go with a "lies in the wind" title but all the info will be there. I cant say exactly when it will be done, but it will be done. Things have just been a bit chaotic here lately and video production has slowed to a crawl. That's an interesting issue with your return. Something like a commercial sized vent diffuser might do the trick. Thought, I would imagine that this will lower the output of your AC a bit. amzn.to/3QAWi0Q
I just tested some K&N filters against disposable ones and they aren't the best but they are acceptable when it comes to removing smoke from the air. It would cost a fair amount to load up this 8 filter design with K&Ns, but the cost over the next 10 years would be way lower than disposables. These are $24 each, so it would be about $200 for a whole set amzn.to/3Vq7oWv Watch my air filters vs smoke video to see how they compare to other filters. I didn't spring for these outside of the CR design but based on the other test numbers, this 8 filter design should clear the garage test space of all heavy smoke (AQI 450) in 50 minutes vs 27 minutes with disposable 3M MERV 13 filters. So in short, they are pretty good. th-cam.com/video/XAJ__E-hIJc/w-d-xo.html Hope that answers your question!
@@freddrawhorn8239 Awesome. I have the parts for quite a few in stock now but there are a lot of orders to ship at the moment. It may take about 2 weeks to get new orders into the mail. Let me know if you have any more questions.
It is worth pointing out that you get a lot more filter area for your dollar just by using 16"x25" filters rather than 16"x20". The difference (today) on a 12-pack is $5! 20"x25" 12-packs are an even better deal. You significantly increase your available filter area with almost no increase in price.
Thanks for buying the fan! I does help the channel a lot. Typically I run it on "4" when I am working but it is fairly loud. If you want to run it in the background, when there isn't too much dust floating around, the other levels should work nicely.
So, received the fan you linked in the description that you used in the video today. However, it is NOT a 4,000 CFM fan! It's 2300 cfm! Was your link incorrect?? It's still a higher rated unit, at least I hope it will be, then the mid-range WEN I was going to buy. Granted the vid is 2 years old, and no where on Amazon's description or CAT's description does it state 4000. I have it now, I have the filters, so we'll make it and at least I'll have something. CAT by CATERPILLAR HVD-14AC - 14" High-velocity Drum Air Circulator Fan. Same model as in the video.
That fan was never 4000cfm. It "moved 4000cfm". They may have just updated the packaging to something less outlandish. Also, the amount of air that goes through the is about 1340cfm. That's what this video is about. The model number is identical to the one in the video. If you have a watt meter and the fan pulls 130 watts it is the same as the one I tested. Hopefully it will work well for you. It always has for me.
In general blowing air out the top creates better circulation through a space, thus improving overall efficiency, especially when the filters are dirty. Blowing air into the filter box is great for sucking dust away from a workspace, but that's generally where it performs best. I'll do a video on it early next year to discuss it in detail.
At this point I think that title might be to harsh. Floor and wall fans are not technically designed to work in a ducted environment and their airflow ratings are therefore inaccurate when applied in that way. I've put a ton of video together and run lots of tests for a new filtration series. I'll have these out over the next 2 months or so. First one will hopefully be out this coming weekend!
Axial fans are optimized for volume. Radial fans are designed for pressure (or resistance). Mixed flow fans hit the sweet spot in between which is ideal for your filtration needs. You can see this in your CFM drops with filtration added. You're wasting over 50% of the air you're shifting with your DIY solution. The ideal fans for you IMHO would be the Soler Palau td silent series which work well even with a little resistance. You don't want to be blowing dust off the floor and making so much noise that you cause more trouble than you're out to solve! It's also nice to pre-filter air hitting the fan for longevity!!
The Soler Palau td silent series seems like a great option for keeping the workspace quiet. Most of these fans a noisy on high. But a $500 price tag on their 1050cfm model with 30% less airflow than the drum fan (with filters) in this video is a steep price to pay. If affordability is not the issue, the mixed flow fans might be the way to go.
I really enjoyed your video. Question, on one part of your video you show dust flowing into the filter. then you show on another part of the video dust flowing into the fan first. Also, if you are spraying in a homemade paint booth, wouldn't the filter protect you from possible fire?
Thanks! The drum fan is reversible. In general blowing air out the top of the filter is best. In some situations, like close to your work bench, blowing air into the filter box can be better. I prefer this method because of the way that I use it. I would only use this type of filter as an infrequent paint booth for very small projects. It's not designed to be heavily used as paint booth. Paint booths require a very different design with lots of air flowing out of the building. If you do use this filter as a small booth, you also need to have very good ventilation to remove the fumes from the area. This filter will not remove the solvents/VOCs in the paint, only paint particles. If the area is not very well ventilated (lots of fresh air in from outside), there is a fire risk!
I tested an older version of this fan and I can not say for sure that they are identical to the new ones. If it is, this video has all the data on it th-cam.com/video/KobogQMf_Xc/w-d-xo.html It's the strongest drum fan that I've tested. Attached to the filter box it should produce about 1400cfm of filtered air.
is there a version of your DIY rosenthal boxes that I can mount to the garage ceiling? floor space is limited... Also, I only use tools / create dust when the garage door is open -- is it still worth it to run a box like this during the cuts? Does it help to run it overnight when the door is closed, or is that too late because by then the dust has settled from the air? Thanks
I will have a design coming out that makes it a ceiling mount possible but not ideal. A custom solution might be best. The filter clips in this video would make changing filter easy from an elevated position. You could set the fan on a timer to pull dust out of the air for 1hr after you leave the space. There wont be anything to filter after the first hour.
Thank you! I do want to do something like that in the future but don't have the time at the moment. Is having wood around your workstation an issue? Would the hood have to be sheet metal?
I followed a TH-cam dust-collector design that didn't require building a support structure. It uses the same Caterpillar fan which simply sits directly on top of a canister filter. I've performed some tests on this system and the results are underwhelming. Your system has a much larger distance between the fan and the end of the structure. Do you think that the added distance between the fan and the structure helps?
I am planning on testing that design in an upcoming video. It's great to get some feedback from someone who built it because a lot of people have asked me about it. I imagined it would be underwhelming mainly because axial fans are not great with high static pressure and the moment the canister fills with dust, it will be difficult for the fan to move an adequate amount of air. Basically, it will get choked off and not function properly very quickly. The hole in the top of the filter is also smaller than the rim of the drum fan. This also restricts air movement. You are probably also correct in your assessment. The more closed in the fan is, the less space there is to develop an air column that can be pulled efficiently through the fan. Hopefully that makes sense. I also think this issue affects some other designs out there on youtube. Sometimes blower fans and inline fans are better for some designs than axial fans. My drum fan (axial) filters are designed to maintain next to zero static pressure so that the fan can function more-or-less normally. For the Wynn canister, I think a inline fan is a better option. I'll be testing a lot of new concepts in the next few weeks that use the parts you bought in a more efficient way.
I've ordered parts to build an air purifier. An uzman ksa-400 fan (200W), and a 405x405mm filter stack consisting of a prefilter, activated carbon filter and hepa (filters 0.3um at 99.97%) filter. The entire stack is 125mm (about 5"). It's for those times that the air quality is bad or pollen is a problem. Mostly fire wood smoke, diesel exhaust fumes (rural area with lots of tracktors and trucks), ferillizer etc. Especially around easter, my neighboring country Germany light fires (garden wood etc) nation wide which often blows over my living area. I have a hard time breathing during those times and avoid going outside. It can last up to 3-4 days depending on wind direction. Hopefully this will help getting some clean air inside despite the outside conditions. I can also use it when I'm soldering electronics, woodworking (cnc, sanding etc). I've ordered enough materials to build 2 of them and/or experiment with differen configurations.
You are correct when mentioning the long tunnel for allowing air to stabilize before reaching the fan. It's called laminar flow Vs. turbulent flow. TLDR laminar flow it's like a quiet in-line fast flow stream of water (air is a fluid), and turbulent flow is chaotic, noisy and non efficient. I've built my own filter for my workshop and have done some research beforehand, and from what I can remember the minimum distance between the filter and the fan should be 10Cm (4" in _Freedom Units_ ). Nice video and keep those fingers away from that saw blade, *yikes* !!!
Blowing into filters and similar loads like heat exchangers is not recommended, it's always preferred from a fan performance standpoint to draw through. The airflow from the fan outlet is turbulent and very directional so you'll get poor distribution, load the filter unevenly and get unpredictable airflow when you compare with the stated fan curve. The comment about fans being tested with ducts in the way you think of it is not always true. If you look at a datasheet for an industrial fan it will have a fan curve which tells you the flow vs static pressure in a standard test configuration, thatc configuration can be any combination of ducted or open inlet or outlet. The fan curve should have small diagram with it that tells you how the fan has been tested. Most of the time the way the fan is tested will correspond to its intended use. A fan designed to be used in a ventilation duct will be tested ducted inlet and outlet, a computer cooling fan will be tested open inlet and open outlet.
Good thoughts! You are correct in that the wear pattern is not even when the fan is pointed into the unit. 6" from the top corners of the filter is more clean than the lower portion. From the standpoint that it is not acceptable, I will disagree in this particular scenario. The fan's performance is virtually unaffected due to the extremely low airflow through each filter. The average filter handles only 20% of it's maximum capacity and at the bottom of the filter where the wind speed is highest in this configuration the flow is at 60% of it's rated capacity (based on 3M MERV 13 specs). I would think that if there were only 4 16x20x1 filters in this unit, the acceptable thresholds for the fan and the filters would be breached, but that is not the case. I was stretching things a bit with the test stand info. There wasn't much that I could find and I was leaning a bit to much on the info from a commenter. The fan curves for industrial fans, specifically blower motors are easier to come by, but box fans not so much. In the end if the fan is used in a DIY filter box, it's helpful to know how it preforms in that scenario vs. a test stand. I am working on a new video that tests air filters against one another and I tried to improve my test stand by lifting it up off of the ground for more free air flow. I can only test these on their side as the my wind tunnel is taller than the garage I am testing in. Hopefully this gives more realistic results. Performance has climbed a bit but no more than about 10% over the testing done for this video. What I figure is that if the filter is pushed up next to a wall you can expect a 10% performance drop and 20% if it's close to a corner. Thanks for the comment! I will try to work in a correction of some kind into to the next video!
Looks like there is a fabric wrapping over the filters. Is there? And if so, what is it? I don't see it in the parts. I am asking because I am going to construct your design myself.
Awesome. That's a good question on the mesh. It's hard to find the exact right option on Amazon. I bought my fabric from a fabric store. I just looked for a non-stretch synthetic mesh fabric material that has holes that are about .5mm wide. This is the most similar material but the sheet size isn't quite right and the price is high amzn.to/3b3B6Oy This material is the right sheet size but the holes are to small and would reduce air flow. It would keep the filters more clean for longer tho. amzn.to/3OAGxT1 Let me know if you end up getting one of those and how they work!
I'm sure it does do that inside the filter chamber but the incoming stream of air is far to powerful to allow any of it to escape. Any of that dust would just get trapped in the filter again.
Excellent question! I am actually experimenting with canister filters including the Wynn at the moment. MERV 15 is as close to HEPA as you can get for the shop and that's nothing to turn your back on. The unit in this video (now called the Model A) can actually support a inline fan system that has a lot of benefits, especially in a 100-200sq.ft work space. This setup allows for a large canister filter to be inserted into it without any modification (I need to check the CAD for this, I know it's possible with the CNC version but I'm less certain about the downloadable design). I will be running these designs through the same smoke test that I did for the other HVAC filters in one of my last videos. I've started to add to this page the current results from testing the3dhandyman.com/what-is-the-best-air-filter/ More results to come on that list in about 2 weeks after I finish the latest round of testing. These tests will include canister filter tests. I have modifications for the Model-A and Model-B that make use of a second layer of filtration with the addition of the canisters. I also have a pre-filter video in the works where you can add a 3rd layer of easily vacuumed surface to your filters for extremely long life, low cost, heavy dust collection. Canister filters are great, but they get dirty, very fast. My aim with the next video series is to design an air filter ecosystem that makes the $300 Wynn last for years without cleaning. I have been extensively testing these new designs in a heavy dust environment and I've been able to really dial things in just in the last few days. Ducting the air away from the filter seem to be a real game changer but there is a catch or two to the setup. Videos will be out as soon as possible on all this... but that might take 2 months at the current rate. I know that's a long time, but I assure you, it will be worth it.
Spent 3 years I. A commercial cabinetry and furniture shop and dust collection physics and mathematical formulas can become wildly complicated quick. Nice video and use a push stick always
You ain't kidding. It easy to have a lot of power loss throughout the system. I've been working at a small sized woodshop and the massive dust collector is only putting minimal airflow through the ports by the tools. So many leaks and bends!
do you have plans for the beastie boy? what's the difference with that one vs. the tall one? I'm gong to build one. just got a CNC and even with vac it's dusty.
I don't have the plans yet but will early next year and will be making one for the shop featured in the Filter Kit videos. The main difference is the fan that they use. I cant say whether or not the standard wall/cage fan is all that great for the task until I test it. Generally having a ducted fan, like the one in this video is preferable. I wans going to build this for a new shop space but the deal never went through. I think the concept might work well for your space th-cam.com/video/OhVWsnTm8iU/w-d-xo.html A prefilter may also help make the filters last longer. I will be doing a video on this in the future.
I tested some K&N washable filters that should last 10 years or so. They preform around the low end of MERV 11 filters but the reusable aspect is a huge plus. I'll be making a video that uses them a few weeks or so. As for the metal ones, the ones I've seen have very low MERV ratings and are only good for large dust. Got any I should take a look at?
@@The3DHandyman I've a couple of air (scrubber/ purifyer) used to help clean up the air. Family with bad sinuses and allergies that this helps. So i'm looking for custom made filters like that of particular sizes. any thoughts? would it work? or are there people who do something like this?
@@sspaceforce I haven't seen it yet. I'd like to give it a shot at some point but I wont have time for quite a while. If you want to filter the air with basic materials you will probably need A LOT of filter surface area to come close to the performance of a disposable filter or even the K&N home filters. These filters are highly engineered for the task. The cheapest method is really to tape a filter to the back of a box fan. The 4" filters should last 1-2 years under normal conditions. For allergies a MERV 11 filter might be all that you need. Allergies tend to be larger particles than other pollutants.
True on the allergens being larger particles. That's sort of why I'd like to test the basic filter concept. For a lot of people, that might be all they need.
I have to say, this video, and more to come, are very interesting. I suspect one advantage of the "cylinder" fan relative to the box fan is that the latter has corners through which airflow can return around to the intake side. Also, when you connect a fan to a duct, that duct creates some resistance to airflow, so the resulting flow rate will be less than for the unducted fan, possibly explaining your noted discrpancies? Indeed, if your tests include a measurement of the pressure generated by the fan (or vacuum for sucking), that would result in much more meaningful comparisons between fans, and between filter arrangements. Hmmm, I can't help feeling this is probably already a topic of study by home-filter-builder enthusiasts :-).
You are definitely right about the the cylindrical housing around the fan helping to improve efficiency. I will test a Corsi-Rosenthal filter in the next video and that placing a circular cover over the box fan does increase performance. I was thinking that the duct likely plays a role in the numbers I'm getting. This is the industry standard for testing but the pink foam that I used may create an undesirable static charge in the wind tunnel that could slow down the air. There are also other factors as well but I will get into those in the video... still trying to collect my thoughts. Testing static pressure would be a nice addition to the video but I'm not sure how that would work in a system that is not a closed loop like an HVAC system. I will look into that. Thanks for the comments and ideas!
i think to better capture the true air speed from a fan, the tunnel should be at least 1 ft wider than the fan to eliminate as much boundary layer as possible so that the centre of the tunnel is closer to the real world air speed without boundary.
For the latest pass on this I used 2 anemometers inside of the tunnel to get a better representation of the real world speed. You are right about the boundary layer though, air at the edges does move more slowly. It's tough making the prefect wind tunnel for each size of fan, so I may just settle for a good test rather than a great test. At this point I am also more focused on finding out which filter preforms best will smoke and other super tiny particles. I will be showing CARD number for all of these some time soon. Air speed is a big factor in filtration but there are more variables to consider when finding the best design for your use case.
Yes, here is the sound data for all the fans I've tested Background sound 40db Lasko @1ft - 63, 60, 55 Air King @1ft - 68, 66, 61 Air doctor HEPA @1ft - 64, 58, 52, 45 Maxx air @1ft - 71, 67, 57 Caterpillar @1ft - 71, 67, 63, 57
Yes I do, here's the build th-cam.com/video/fixd7LqnWow/w-d-xo.html For what I'm working on at the moment having the air blow in to the filter helps to keep local dust down at my workstation. If I was working with tools that are more likely to blast dust out into the room, the "pull configuration" might be best. The build video goes through some tests with this. Overall the "push config" seemed to yield the best results. Thanks for the comments!
Thanks! Yes, they should reduce dander and pet hair which are a big contributor to the smell. I will have a video with some modifications to this design that use inline fans as well. You can run a duct to the them and install a huge charcoal filter on them to further eliminate smells, but the system does get pretty large at that point.
Great videos. Do you know when your next one in the series will be published? What type of fan are you using in the "compact" and "beastie boy" units you preview? Do you have plans for them you would be willing to share?
Thanks! The video for these new units will take 2 weeks or so for me to get out. The construction style will be identical to my floor model filter so watch that for general construction concepts. I will be making a version that uses only plywood as well. Hopefully I can get those drawings done tomorrow. Plywood/2x4 Construction Drawings: the3dhandyman.com/workshop-air-filter-series/ Here are the Fans and Filters I am going to use: 24in fan for "beastie boy" 5850cfm amzn.to/37q96CV merv 14 filters - 20x30x1 amzn.to/3vSWQnW 18in fan for "compact" 3190cfm amzn.to/3kS9YmS merv 14 16x25x1 amzn.to/3w9r98R There are cheaper fans out there but I am trying to source fans made all or in part in the USA. Here is an "8800CFM" version that is not USA made. I can not possibly imagine that it is capable of producing anywhere close to 8800CFM. It is the same size as the TPI fan but has 20% less horsepower. This one should work fine with "beastie boy" but there are no posted dimensions, so I can not say for sure. amzn.to/3ymA6hV
@Jason Shapiro Hi Jason. Sorry for the delay getting the next videos out. I'm currently working to fulfill order for the mushroom castings that are featured on this channel. Hopefully the next videos in this series will be out in the next few weeks 🤞
Lol, yeah. I need to give this some time but the workload the last 2 months has been off the charts. The next video in the series is filmed but I need to cut it together. The builds will take until next month. Sorry for the wait, and thanks for your patience!!!
Good question! The air coming out of the unit is at a much lower velocity in push mode. That allows for better local circulation and a reduction in fine dust being picked up in the fan's wind stream and deposited all over the shop. This works great if you are working right next to the unit and not throwing dust at a high velocity in the first place. If you are using a saw or grinder, etc and the dust is already flying, pull mode is fine for filtering the ambient air as any standard air filter would. Push mode is not going to move air around the workspace quite like pull mode does. Hope that clears things up 👍
Can you run the filters in series so a lower HEPA filter picks up the bigger particles, and is backed up by a higher HEPA filter. That would decrease the need to change the more costly higher rated filters? You may have already addressed this, but I could not find it.
You most definitely can do this. Technically the term HEPA is reserved for HVAC filters over MERV 17. So if you are using a HEPA filter, it should be the last one in the series. Before the dust reached the HEPA though, you can use lower MERV filters to filter out a lot of particulate. I will be putting out a video on this concept next month. In it I'll show off a new setup for the filter in this video (now called the Model-A) that allows for 3 layers of filtration and more.
@@The3DHandyman Thank you for the rapid response. I really enjoy your videos, especially the scientific break-down. Looking forward to seeing your next one.
Good question! After the last round of tests, I think I can confidently say that an extra filter on the bottom would not change the output of the device. There is simply not enough free air underneath the bottom of the device. It's likely that 95% of the air that would be pulled in through the bottom would get pulled in through the side filters. The 4 and 5 filter (one on bottom) corsi-rosenthal designs I tested had the same output unless the 5 filter design was raised at least 3 feet off the ground.
I take it this video answered your your question :) Glad you are enjoying them! More air filter content on the way, including a video about this concept specifically.
@@The3DHandyman Thank you very much. I am building a 12" version of this. also a seprate project of using a 4" duct + duct fan, to draw the heat out and away from my PC witha custom boot/hood that fits over the top of the system. kind of a cool idea
@@TwistedLogicGaming I am working on a desktop edition of filter and I love the idea of blowing the filtered air into my PC. Maybe I'll make a video on the PC cooling option at some point!
Really, really awesome! 👍 Thanks for investing the time to gather all this data and information then sharing it with us. I'm "blowing"💨on over to your next video! 😂Take care and have a good one, Adios!👊
Thanks for watching! I'll have a new series on air filtration out in a month or two. I just need to find the time to work on it! Then some day I'll make more non-air filter videos 😎
@@The3DHandyman I'd like to "clear the air", I see nothing wrong with this content, it is such an important topic. Sorry, sometimes I just can't help myself. 😉
You don't have to clean it ever. At least I never have. The dust gets stuck to the filters and you just throw them away. I collected 1lb of ultra fine dust on the 8 filters before air flow dropped noticeably. If you run the fan in the pull configuration then the dust builds up on the outside of the filters which is arguably worse because you can knock it off if you bump into it. I'll do a detailed video on just this concept some time.
Most fans are pretty much the same, so anything goes for that type of design. A good rule for filter sizing might be to add about 5 or 6in to the diameter of your fan. That number will be the long side of the air filter. For the base beastie boy design the fan is 25.5in wide and the filters are 30". If your fan is 32in in diameter then the ideal filter might be 38"?
I have not but this design as it is can be mounted to a ceiling. There is a new 4 filter design that I haven't made a video on yet. It's pretty much the same as the 8 filter design, just a bit easier to make. Plans are here the3dhandyman.com/diymodelb/
Thinking about building the ceiling mounted versions and hanging them from my 92" garage ceilings (kinda low). Just looked at the plan and it looks like the fans are pointed up (towards the ceiling). Wouldn't it make more sense that they're facing downwards, where there's a greater volume of air to pull in?
Good point. The extension legs could be mounted on either side. At the time I made this I hadn't made any printed parts for holding the fan in the sideways or upside down configs. I just printed the first batch and I will have them available for download/ purchase on etsy by this weekend. With these you can make legs or just screw the unit on to the wall and go with 6 filters. The performance would be reduced a bit but you would probably still get 800-1000 cfm and save some floor space while you are at it.
The fans would both need to be pointing out or pointing in for the air to be filtered. A push/push or pull/pull config. If you did either one of those you should add a lot more filters to accommodate for the extra air flow. Double fan, double filters would be good. That would certainly filter a lot of air! You could also run 2 separate filters and accomplish the same thing, tho. I hope that answers your question!
I wish a pulmonologist would chime in and explain how dust can cause nodules in the lungs. People tend to think if they aren't coughing when they encounter dust, there body is handling things just fine. Unfortunately, that isn't how it works. Wear your dust masks folks, and get something / build something that will eliminate the particles from the air when possible.
@@The3DHandyman I went to a pulmonologist and he showed me my x-ray and I thought I had cancer. I had nodules all over my lungs. He said "did you grow up in a dusty environment?" I thought about it a while and I realized I used to ride dirt bikes as a kid and it was always crazy dusty. He said well that will do it. Will those nodules turn into cancer? Who knows, but if I knew then what I knew now I would have been more careful. Every time I see a video like yours I really appreciate what you are doing showing people how to filter the air so their lungs dont have to take the brunt of it. Especially when you are sanding on man made materials with bonders...
The internet says that they are between 10-30 microns on average, however using an air pollution monitor around a saw will show particles from 10-.03 microns as well. My newest video is about filtering super small particles. I will also make a video in the next month or two about adding pre-filters to capture most sawdust and help extend the life of your more expensive filters.
I have not! Thanks for the idea. Do you have a link? All I'm seeing is MERV 8s I just got 4 K&N washable filters to test but they only come in at MERV11
I found the video you are talking about! He didnt say the cfm output but he did put an anemometer on the outflow and the Wynn+Ducted fan design appears to put out 500cfm on the dot for about a $350 price tag. MERV 15 and cleanable is a huge benefit but I think I still prefer the higher airflow. What do you think?
The industry (at least in EU) usually use HEPA filters (MERV 17 and above) and because they use these filters, they also need to use centrifugal fans to create enough pressure to actually pull enough air through these filters. You totally ignored this aspect when you compared your purifier to other purifiers on the market. Also, you didn't measure the smallest particles in the air. As you've mentioned, these particles are actually the dangerous part of the dust. You've maybe created cheaper air purifier, but it's looks like it's not good enough to protect your lungs from fine particles.
When I found your video I was really enthusiastic. I wanted to copy your design but with custom made filters because I don't want to rely on some replacement filters with pre-defined sizes sold online and I also want to capture more fine particles that MERV14 filters do. I wanted to use HEPA filters. So I went to a company that makes them. The first thing an engineer in the company asked me was if I already have a fan, how much of pressure does the fan produce and how much particles do I produce in my workshop. I told him about the Caterpillar fan and he told me that this is not a good fan since it doesn't produce enough air pressure and that the CFM is not the metric they need to make a filter. As I said, they need to know the pressure and the number of particles (of different sizes) in the workshop.
@@noID457 The Caterpillar fan or any axial fan is not ideal for use in high static pressure environments. HEPA filters certainly produce more static pressure than disposable HVAC filters. The work around with my designs is to reduce static pressure (with new filters) to near zero in my designs so that the fans can run as they would normally without any filters attached. It's not what an air filter manufacturer is going to choose because they are not interested in DIY design concepts. Although airflow (cfm) is not necessarily their main consideration in designing a filter system, it is absolutely a factor in determining the number of air changes per hour. This is an important metric when determining the efficiency of the system. If you want to use HEPA filters, Inline fans may be a better option. I have been using these for a while and I am making a few videos about them now. They are better at dealing with static pressure but are less costly and power hungry than centrifugal blowers. You can use any fan you want for a design as long as you have enough filters to allow it to function properly. Just look at the "corsi-rosenthal" design, a manufacturer will never choose a box fan as a power plant for an air filter, but it still works well. Here is a breakdown of fine particle removal with various filter brands that I did. HEPA will of course be better, but you will need more of them or a fan type that can better handle high static pressure, or even better, both of those things th-cam.com/video/XAJ__E-hIJc/w-d-xo.html
Pointing the fan into the frame seems to work better in houses. It cleans the air through doorways a bit more effectively. If the fan is pointed upwards then the fan will stay more clean from spores. That would be a different sort of benefit. It's up to you
@@The3DHandyman yea I'm learning more by nerding out on these videos, 2 inch will capture more dust overtime but 1 inch is more efficient with good airflow . I'm looking at the 14 inch CAT fan for killer CFM and Merv 14 if I can afford it.
I'm eagerly following this filter series! Im interested for the potential of low cost DIY air purifiers for general home use. Ive not had luck finding a fan thats ideally affordable, powerful, quiet, and energy efficient. The centrifugal fan in the Coway Airmega 400s purifier is pretty good, whatever that one is. Rated at 410CFM of HEPA processed air drawing 69 watts. The downside is the ~$400 price tag and high replacement filter cost times having one in each room. Your videos are giving me good info.
Awesome! I was plaining on testing a home HEPA filter for this next video. I know someone with an "air doctor". Retail about $500. Apparently it's rated at 373CFM max. I'll see if it can even pull that off. You are right, I think the HEPA filter replacement is a huge long term expense. I will also test out a Corsi-Rosental box with 4 and 5 20in filters. It's not super attractive but I suspect it will preform fairly well. Are you looking for something nice looking? That might be an interesting project. I found this great centrifugal fan section on Grainger. I was thinking about using one for a paint booth but it could also be used as an air purifier fan. Not the least expensive approach tho. The drum fan in this video would move more air for less money but it is quite large for in home use. www.grainger.com/category/hvac-and-refrigeration/ventilation-equipment/oem-specialty-blowers
@@The3DHandyman Yes, to save money one can utilize the washable MERV 13 air filters which are $40 per unit or $80 for two or $169 for four of them; when one considers that Filtrete MERV 13 air filters go for $23 apiece at Lowe's one breaks even quite literally at the one year mark if one changes their MERV 13 air filters every three months typically.
I'm getting my materials ready to build this. I looked through comments but haven't seen anything: what's the mesh screen you have around the outside of the unit? Or is it just my imagination haha.
Nice catch! Sorry for the late reply, was out of town. That is a .5mm (500micron) mesh screen. I just bent to a fabric store to get that. I talk about it in this video th-cam.com/video/fixd7LqnWow/w-d-xo.html If you can go to a store to pick something out, that would be preferable but if you have to find something on line, I have recommended these 2 products before but I have not tested them myself. amzn.to/3b3B6Oy amzn.to/3OAGxT1 I am making a kit for this version and I hope to get a seamstress to make filter covers for the units to make this an easy addition for people. It definitely helps prolong the life of the filters
Haha, ok yeah I thought you did mention it but then I couldn't find it again. Anyway, thanks so much for responding. I love the idea of filter covers. My filters arrived yesterday and the fan arrived today - seems like my weekend is planned! Thanks again for all your help!
I built box fan filters using 4 inch filters instead of 1, and they seem to do the job well enough, best budget option. You can even use more filters if you want more airflow.
Extremely well researched and very well done, thank you for this! I would love to build the downdraft version - I think it would work well for flying dust from mitre and table saws. Do you have plans available for that version? Thank you.
Awesome! I don't have any plans drawn up for that one yet. I can make some for the next video but that will take a little while. There is a lot going on at the moment. It's essentially the original design flipped upside down with framed legs if you want to give it a shot. If you do, let me know how it works! Here is a link to the plans for the "Original Air Filter" the3dhandyman.com/workshop-air-filter-series/
@@The3DHandyman Thank you, will definitely give it a shot! Just have to source similar merv 13 or merv 14 filters in Canada. I stupidly cut some mdf boards in my basement with just basic dust collection and regretted it instantly.
Not sure if it is too late to ask but what is the depth of that fan? Trying to figure out if I build this exact system if it will fit where I want to store it. Thank you!
When the fan is blowing out of the filter it causes some of the local dust to get caught up in the air stream leaving the filter box. From there it ends up spread all over the shop. I talk a bit about it in this video th-cam.com/video/fixd7LqnWow/w-d-xo.html
@@artyk242 That's an interesting idea! I'm not sure if an engine air filters comply with MERV ratings though. They are designed to be high air flow and function in dirty environments so they may not be good enough for respiration. Project Farm did a video where they tested engine filters and at a quick glance it looks like particles up to 5 microns were slipping through some of the filters tested. If you buy a filter for a 6 cylinder of above it should be able to handle a 2000 CFM, so that check out at least. Cabin air filters might be a fine alternative to engine filters.
That's called a 9205 N95 Aura Particulate Disposable Respirator. Overall a pretty good seal and comfort level. It doesn't touch your mouth when you talk. The nose bridge isn't the best after several hours of wear. amzn.to/397LCTx
Awesome to see you doubling down on the content that worked for you! Just getting started with taking TH-cam seriously and the 3D printed kits/parts for my projects was an avenue I was considering. It would be cool to hear about how well this works out for you on a monetary level and how you balance the workload of making videos and these parts/kits. Thanks for sharing!
I figured it was time. It's definitely my bread and butter over here. I'll be setting up an Etsy shop for the prints, they take a big but help reduce shipping costs. Should be interesting to see if there are any takers. In the past I referred people to Make XYZ but never realized the prices on that platform have gone through the roof lately. I couldn't believe the price they wanted for the power inverter case. Ask me again in a few months and I can give you an update!
@@j._7054 Sure! Sales on 3D printed parts have been steady but don't generate a whole lot of income. Typically less than $100 per month. I am launching a line of wooden air filter kits that I hope will increase this a bit but between the cost of shipping, manufacturing, and Esty fees they are probably going to be out of the price range of many people. I have a lot of air filter related content on the way and the videos are preforming well but they are time consuming and costly to produce. Ad revenue at this point really doesn't even cover the cost of video production. So to sum things up, monetizing the channel at a level above "side hustle" can be a real challenge.
@@The3DHandyman i hear u. I ordered one of those "4000 CFM" caterpillar fans yesterday using your Amazon link. My garage looks forward to some much improved dust collection/air filtration soon thanks to your vids
I would like to build one of those at some point. I see you are painting some car parts with HVLP sprayer. Very nice! I once spent the day in a paint booth for semi trucks and they had a system sort of like the one I plan on building for my new workspace. Here is a 3D video on that subject. I have not built it yet. th-cam.com/video/OhVWsnTm8iU/w-d-xo.html Over the top of the filters you should use "Paint Booth Exhaust Filters ". Google those. They are cheap but wont filter out all of the paint particles. They just help to keep the air filters clean for longer. Keep in mind, that it's best to exhaust the air to the outside of the workspace. You can blow it out one window and put another air filter in different window to make sure you are not pulling dust into the open window. This should help avoid paint defects. You could use the design in this video and wrap it with the paint booth exhaust filters. Point the fan up so that the air is filtered before it does through the fan. Just be sure to have great ventilation. The fan motor can get very hot when its 95F or 35C or hotter.
I built the 8 filter version with the 2500 cfm fan for our non-profit Made4Me shop and it has made a significant difference to the air quality. We build adaptive furniture for handicapped kids using cardboard, which leaves very fine dust in the air when cut. Thanks for your work here!
Wonderful! That's good work your doing. I'm happy that I could help out in any way!
This is awesome! Thank you for making this video. Definitely going to build a few of these for my woodshop.
Awesome. Thanks for watching!
Have you tested dust performance with an air quality tester between push / pull configs? I've read a few articles that having the air purifier blowing air straight up and sucking from the bottom provides an increase in performance. Since CFM isn't a qualifier of how much is being filtered.
Yes I have but the video isn't out yet. If you are close to the filter and the dust gets pulled right in, that increases the efficiency of the unit. If the dust source is far away and the filter is just processing ambient air, the pull config works much better. I'll do a video on this concept some time soon.
Thanks for the comment! Sorry for the late reply, it's been a busy month.
Are you still selling the kits? I'd order one.
I sure am. The wait time is a bit long at the moment but that is improving all the time. Let me know if you have any questions! www.etsy.com/shop/The3DHandyman
Damn, guy. Selling the discounted 3D-printed parts and providing free plans is really kind of you. Thank you.
The 3D printed parts are also free if you have a printer of your own! I make it a point to ignore all the business advice I get. lol
@@The3DHandyman Liked, subscribed, links used to add items to cart.
@@Saileahgaz Thank you! Those help a lot.
@@The3DHandyman lol. dont change.
Impressive dedication on your testing rigs. Thank you, truly. That's a public service I know took you some time, effort, and money.
Thanks for noticing! I'm trying to be as scientific as possible on a budget. The rigs aren't perfect but they are good for side by side comparisons.
...maybe I'll have CGP Grey's subscriber numbers on day. Hah
Lol I didn’t realize I was a nerd until it just hit me that I’m watching these videos while doing dishes and ONLY listening to the audio. You’re doing an incredible service for DIY peeps at home. Thank you so much man. ❤
No, no. Thank you!
Dude! How am I just discovering you! You are a real builder, well spoken, and your graphics make it soooo much easier to understand how it goes together. Thanks!!!
Awesome to hear that. Thanks for the comment!
This is a great DIY build! I built and have been using mine with the original orange fan for quite awhile now and can attest to its function. With some mods to the original plan, it is now even better. With an added filter on top of the fan to keep dust out of the motor, and a longer power cord/external switch, this unit keeps my small garage shop free of airborne dust. I have ordered the Cat black fan to upgrade the power of my unit. No more hacking cough after a day making sawdust. Thanks again 3D Handyman for putting this plan out for all to use.
That's really great to hear! Thank you for the comment.
Thanks for the great idea and plans, you are a gift. I built one of these with 3/4 MDF, had to make a few adjustments to the plans to make it work, but it does. And for kicks, I combined it with a modified version of this build (th-cam.com/video/ccPqfBEu5PI/w-d-xo.html). Tweaked the code to avoid the fan cycling on and off around the threshold point and added in a 8 by 8 LED matrix panel to show me at a distance what the air quality was at. Green for good, yellow for 'starting to get punky in here', and red for 'mask up'
Sounds like an awesome build! I hope to do some automation like that at some point. Thanks for the comment!
It's crazy how people come up with the same ideas all the time, I've done this on my intake for my old greenhouse i built in the basement. 2 box fans listed at 2200 CFM and 3 filters plus 2 more fans for the exhaust with another 4 inch filter to catch pollen. Works great, i should've gotten these bigger fans though cause these things kick ass
Sounds pretty cool. I got into vertical farming for a while. Our space definitely needed what you built!
These drum fans are great for all sorts of uses. I also found a fan that might be a possible upgrade for your system. It comes with it's own fan shroud like the drum fan www.lowes.com/pd/Utilitech-Pro-20-in-3-Speed-Indoor-Air-Mover-Fan/1000018619
A box fan has a fractional HP motor. Generally around 1/25 hp to 1/32hp. It's merely designed to move air, not draw it through static pressure.
A furnace blower on a 3 ton air handling unit employs a centrifugal fan with a 3/4hp motor. And it's rated to between 900-1300 cfm. I can provide the tables from the manufacturer upon your request.
Design of blades, and housing matters here. A fan meant to just push air with 0 static pressure and 0 resistance can use propeller blades. Exhaust fans get away with them because often the air they are moving is hot (think kitchens) and hot air naturally rises. So the fan is actually just directing it out a vent. Same principles with a chimney on a wood stove. You get good draw when the fire generates enough heat to start pushing up through the chimney. Until that point the fire can actually smother.
Air becomes denser (and heavier) when cold. Humidity also affects characteristics of air. All these things will change your fan's performance.
Try placing the Corsi Rosenthal Box filters in the tunnel and have the fan pointed into open air. Place your anemometer anywhere in the tunnel and check wind speed velocity.
In all air filtration systems emphasis should be on draw rate. Nobody cares about exhaust rate because that's filtered air. Measure draw rate.
Impelling dust into your box (pusher configuration) your anemometer will have a high velocity because it has 0 resistance. On the other hand your math equation won't have the huge surface area, but that's how the math has to be done. The design of the CR Box pulls air through filters, and thus resistance to flow becomes a factor. So you measure air flow drawn through the filters.
I have personally put a lit tea candle inside my CR Box. The air flow through the filters did not snuff the candle out. Made me scratch my head and realize the purported math was wrong. If you put a tea candle next to your AC's return duct it will snuff the candle out. A centrifugal fan is specifically designed to work when resistance and pressures exist. It also is designed to create a low pressure environment inside the return ducts. Further inducing house air to enter and go to your furnace, and A-coil.
www.ccohs.ca/oshanswers/prevention/ventilation/fans.html
GREAT JOB! I love your curiosity and willingness to investigate. You've the mind of a real scientist and critical thinker.
It seems like the intake and exhaust air flows must be identical right? Once the unit is running for a set amount of time the internal turbulence dies down and a stable air column forms. There may be some level of static pressure after that point inside the filter box but that number must be a constant, not increasing with time. I'm no mathematician but it seems to me that there can not be more air entering or exiting the device. The numbers must be the same?
A thought on the candle experiment... maybe the air moving through he filters is just doing so in a less concentrated state. There is a lot more area for the air speed to diffuse through the filters. The filter material also likely produces a column of air that is smooth and lacking in turbulence. If the candle is in the center of the CR box bottom then air will move in equally from all sides and the velocity of the air in the center of the box may be near zero as the air comes in equally from all sides. This may only apply when the fan is in the up position with 4 filters on the sides. Just a thought!
You are right about centrifugal and inline fans being better for high static pressure applications. The standard CR design does appear to be somewhat restrictive. If the design instead uses 20x30in filters the 4 filter design is actually able to hit no zero static pressure on the filters with 3M MERV 13s and an Air King box fan. The wooden kit that I tested them on does create a 15% loss in airflow vs the box fan without filters or a kit. A blower like this ( www.grainger.com/product/DAYTON-OEM-Blower-Rectangular-1TDU2 ) would be less affected by is restriction than the box fan, however it's maximum capacity is 1200cfm and that is also the output of the Air King. When the Air King box fan is $50 and the blower is $340, the best value is quite clear.
I'll be testing a popular ceiling mounted design at some point and I think the issues you talked about with the shape of the fan blades will be more apparent due to how shallow the filter box is.
I also have a design for a centrifugal fan powered filter but that video is a little ways off.
Thanks for the opportunity for some critical thinking! I am still working on the script for the next air filter video and it helps a lot.
I'm a little curious why you wouldn't flip the fan over to pull air through all the filters rather than blowing into the filters?
Just seems like you'd get more air filtered by sucking air from the whole box.
That is true in some cases but not all. I'll talk about it a bit in an upcoming video and get into more detail in a video completely devoted to the subject. It is a question that people ask a lot.
Do you think this has more CFM than the Donaldson P181038 Filter?
It does and with 3M MERV 13 or 14 filters it is also significantly more effective than the Donaldson. The Donaldson acts more like a MERV 11 in my tests, not as good as the Wynn of the same size but definitely more reasonably priced.
Great stuff! This series of yourinspired me to rebuild my single-filter, box fan version. I love everything about what you've done here: good methodology converts specs into the real world. Thank you.
Happy to hear it! Thanks for the comment. Lots smore on this subject to come!
I was wondering if an air filter like the one you made is good for just oulling natural dust out of the air in our shop. Is it something you need to run all of the time or just occasionally?
I tend to only run it when I am making dust. Some people have put them on timers to that they run for an hour or so after they stop working to capture any remaining dust after they shut things down for the night. You could also keep it running on a lower speed if you are trying to keep the air free of dust if you have paint drying or something like that. It's really up to you
Hi there - thanks for the great videos on air filtration! I am thinking of building your design for the "Compact - 1700CFM Ceiling Mounted". Is the intention of this for the fan to be blowing inward (up) or outward (down)? Thanks again!
Hello! Sure thing. The "compact" design is intended to blow air downwards. This will keep the fan more clean and be more safe in the long run.
Thank you again !! @@The3DHandyman
Really bad idea because First your motor should be a centrifugal motor for high rate static pressure. You talk lime a guy who knows about CFM but we don't really care it when in fact its more about STATIC PRESSURE.
Plus, your motor is placed in the wrong side. Your motor should be place at the exit, BEHIND your filter, otherwise your dust is going inside the parts of your motor...
I don't know how the algo got me here, but i'm glad it did. I have massive attic work that needs doing, and it's beyond disgustingly dusty up there, especially after just having my roof replaced. I started using a lasko fan with a cheap 1" filter, letting it get sucked on the inlet side. it helps, but I can see building something better and letting it feed for a couple hours while periodically hitting everything with a battery powered leaf blower, is going to make my life MUCH less of a living hell. So thanks for that, and for convincing me to spend money. :D
Any time! Haha. I actually cleaned up a similar space in just that same way. Kick the dust up with the leaf blower and let it get sucked up by the filter. Don't forget to wear a tight fitting mask 👍
Hello! I have sent you a message on Etsy about the Model B box fan. Please review your inbox and reply. Thanks! Ray
Do the pc fan CR box filters really push the same CFM at a fraction of the energy consumption of a box fan CR filter? Some clean air kits claim 7-10 watts!! That would make it over 10x more efficient than the air king box fan on its lowest setting!! 😮 Definitely something I want to consider, since it’s much quieter at almost the same claimed given CFM, if that were true.
An array of PC fans would be 10 times quieter, and require 10 times less power.
Thank you for objectively testing things. If I could block every channel which gives opinions without tests, I would. Instant subscribe from me. What brought me here is my interest in filters for VOCs with activated carbon--thinking of options for a cage for filter media which is cheap in bulk, but expensive in genuine replacement filters.
Thank you! I have some ideas for this and the video will be out in a few weeks. I'm going to use a large carbon canister for the test. I'll also pull the canister apart to see if I can easily replace the media to save $$$ in the long run.
I will be switching to an inline fan for this because the axial fan in this video is not great for high static pressure loads that you get with lots of carbon.
Not a bad impersonation of CGP Grey's performative TH-cam voice.
Question: Do you have any data comparing the standard 1" thick filters with the 4 or 5" filters on the market?
Impatiently waiting for the rest of the series! Really interested on what went into "Beastie Boy"!
@captainhook426 The thicker filters offer more filter surface area. A 4" filter might have several times more material than a 1" filter, but probably not 4 times more. I can add the data into the next video that can illustrate the concept a bit better. I hope that will be out next weekend.
I just finished testing a large box fan with a 20x20x4" and the fan went from 1700cfm on its own down to about 550cfm with the filter installed.
I'd like to build the Beastie Boy but I don't have a need or the $$$ to test it out yet. Hopefully someone will watch the video and order one so I can test it? We will see.
Thanks for the comment!
I'm not sure if you have see the new video but I test out these options in it! th-cam.com/video/KobogQMf_Xc/w-d-xo.html
At about the 6:50 timestamp, the question was raised about how to calculate the “open area” of a filter. The open area is the total surface area of the filter material, not of the filter cage, so to measure it remove the filter material from the cardboard cage and stretch it out on a flat surface to remove the pleats, then measure its area. The effective area is actually a bit lower than that due to obstructions like the plastic bands and because the airflow is not normal (perpendicular) to the filter material due to the pleats.
Why not feed the fan into a dust collection system instead of a box of filters? I'm looking at a collector with 2 x 100mm ports. One I could use for powertools and other connect to the fan. So it's blowing in and sucking at the same time. When the collector is off the fan just blows into the collector. I'm wondering if having one vent with extra blow will improve the vent connected to the tools because the collector output would be increased. Anyway, so I'm thinking why buy a collector and air filter when the collector with a fan could do both.
I do like that idea. I'm not sure how it would work in practice because airborne dust is generally extremely fine and it does not settle out of the air like dust that goes through a dust collector where some centrifugal movement will cause it to drop into a bucket. I generally run a dust collector at the power tool and then have the filter running in the background, it's not really a great replacement for a dust collector itself.
The fan also cant handle chips or vacuum hose size tubing. The static pressure in this scenario is to high for the fan to function at an acceptable level. Impellers are better for dust collectors than axial fans.
I can imagine a system that would make this a reality but it would probably be quite large!
@@The3DHandyman The filter on the collector won't last as long since it will now be holding the fine dust. As you say it won't drop into the drum. But is that any different than the fine dust within larger dust coming from the power tools. From the fan to a 100mm pipe/vent id imagine some cone shaped joining the two. Blowing down a pipe while also sucking from the other end might have some physics complications. I'm not an expert and just wondered why blows into a box with filters when most shops have a collector. If I'm buying the collector and a high velocity fan anyway. Might as well try it. Failing that I'll create a separate box and filters for the fan.
@@ProjectKelstone That's a awesome experiment. Let me know how it turns out. I may do a video on something like that one day.
I have been working with prefilters for this designs and others that should help extend the life of the filters. Even without that, they seem to last about a year before they start to lose performance. I weighed a set of filters on the Model-A that I've been using as a dust bin for the last year and there was about 1400grams (~2 liters) of ultra fine dust on them. So, they can handle a lot and still keep going.
I picked up some laskos average price 20$ im wanting to order your kit C but got to thinking about a hack. What about adding feet and flipping on its side and put 2 laskos on opposite ends blowing outwards. ?
The fans would probably need a lot more Velcro and/or screws to hold them on in a horizontal configuration. I could send you (2) top pieces in place of the (1) top and (1) bottom.
(4) 20" filters will probably not be enough to handle the amount of airflow that two box fans can produce. The B kit (20x30" filters) would be better in that respect. The 20x20in filters will probably be better off with just 1 fan.
The edge of the unit is fairly narrow, so your foot options wont be extensive and you would have to custom mod something but there is no reason why this is setup wouldn't work.
If you want one, just message me on Etsy or you can just order one at the regular price and I will ship you the custom version. Just be sure to add a Note at purchase about this conversation.
@@The3DHandyman I was thinking for a unit to hang from the rafters... I dont think blowing air out both ends would be good for use right next to a dust source. I did pick up a box of 12 airguard merv 13 20x20x2"(19.5x19.5x1.75) filters for 15$. does your kit C work with 19.5?
@@elkskiutah8204 Yes, the kits works with all filters roughly 20x20 in size. Many brands of filters fall into the .5" to small category. The kit will also fit 1.75in thick filters just fine. Be sure to leave a note at checkout about sending 2in filter clips with your order.
Where can I find the drawing? Thanks!
At the bottom of this page there is a link for "The original air filter"
the3dhandyman.com/workshop-air-filter-series/
Let me know if there are any issues!
You should also try to measure the difference in pm2.5 coming in and coming out of the system, especially over time.
I do in this video th-cam.com/video/XAJ__E-hIJc/w-d-xo.html
The version in this video will get tested in the next release. It manages to filter smoke out of the garage in under 30 minutes with 3M MEVR 13 filters.
Lies in the wind.... Partly cloudy with a chance of drama!
This is great content, thanks for your work on it. I wonder if you've considered or tested cartridge cylinders matched with the Caterpillar fan? The Wynn 35B222NANO Cartridge Kit filter is more expensive but smaller, MERV 15, and 222 sq. ft of filter surface area means tons of capacity by my math. Very simple "assembly"... I saw this on the MMCC_Woodshop channel.
Great question! I actually got some canister filters to test with. They are very similar to WYNNs in their construction but not exactly the same. You can also get 2 for the price of 1 WYNN filter and they are still made in the US.
As for the design of the filter in the MMCC channel... in general I think it works but it could work better. The hole in the top of a WYNN filter misses the outer edge of Caterpillar fan by about 1inch. The out edge happens to be where air is moving at the highest rate. So, the filter itself accidentally becomes an unwanted obstruction.
My guess is that, despite the increase in filter surface area, the WYNN+CAT design may only be able to output about 750cfm with a brand new filter. It would be nice to know the exact number, but I bought a canister filter that isn't quite as wide as the one used in his video so without dropping another $300, I cant say for sure.
For canister filters I think that inline fans are a better option because of how well they fit on the canister and how well they handle static pressure. I'll cover all the positive and negative sides of the design in an upcoming video.
I'm also making a new kit and free download for my mods to this design. Those modifications do make assembly a bit more complex than the super simple method shown in the MMCC video but I hope to improve the long term performance for a similar price point.
Why not use an inline duct fan?
I'll have a new video where I test inline fans on this sort of kit out soon. The one I use doesn't move as much air as this drum fan but it is still very effective when ducted. In some cases ducting the air makes it more effective even without the added cfm.
I was wondering about MERV ratings, and whether they are the total percentage they can remove over time, or for a single pass. It sounds like it’s the latter, but I struggled to find any good information on this. Do you have a source that talks about this specifically? Thanks so much for making these videos. Really an incredible resource.
Thanks! I believe that the the MERV numbers are in reference to the % removed per pass but I don't have a source on that.
Getting in love with your cfgs
Hello Sir,
I don't have a shop to build one of these units. I'm wondering if you will build the frame and ship the necessary parts (excluding the fan) that I may assemble and use in the space I need it in? Thank you, John
Hello! I have made some changes to these kits in the last few months and now the same features of the design in this video is available in a slightly different package www.etsy.com/listing/1373712349
They temporary assembly video is available here while I work on the official version
th-cam.com/video/MLF8qv1tGSQ/w-d-xo.html
If you have any questions at all, let me know!
Where is the "Lies in the wind" video discussed at 46 seconds? My AC ceiling return pulls most of its air through the center of the filter, which wastes most filter material. I am wondering if a plenum (box) above the grill and filter would better distribute the intake air over the entire filter.
I have a whole series coming out in a month or two. I probably wont go with a "lies in the wind" title but all the info will be there. I cant say exactly when it will be done, but it will be done. Things have just been a bit chaotic here lately and video production has slowed to a crawl.
That's an interesting issue with your return. Something like a commercial sized vent diffuser might do the trick. Thought, I would imagine that this will lower the output of your AC a bit. amzn.to/3QAWi0Q
Hey bud have u ever tried reusable filters like the electrostatic furnace filters would that work ?
I just tested some K&N filters against disposable ones and they aren't the best but they are acceptable when it comes to removing smoke from the air.
It would cost a fair amount to load up this 8 filter design with K&Ns, but the cost over the next 10 years would be way lower than disposables.
These are $24 each, so it would be about $200 for a whole set
amzn.to/3Vq7oWv
Watch my air filters vs smoke video to see how they compare to other filters. I didn't spring for these outside of the CR design but based on the other test numbers, this 8 filter design should clear the garage test space of all heavy smoke (AQI 450) in 50 minutes vs 27 minutes with disposable 3M MERV 13 filters. So in short, they are pretty good.
th-cam.com/video/XAJ__E-hIJc/w-d-xo.html
Hope that answers your question!
Thank u for answering wife and I are going to order your tower I like the design
@@freddrawhorn8239 Awesome. I have the parts for quite a few in stock now but there are a lot of orders to ship at the moment. It may take about 2 weeks to get new orders into the mail.
Let me know if you have any more questions.
It is worth pointing out that you get a lot more filter area for your dollar just by using 16"x25" filters rather than 16"x20". The difference (today) on a 12-pack is $5! 20"x25" 12-packs are an even better deal. You significantly increase your available filter area with almost no increase in price.
For sure! 20x30s are also just about the same price as 20x20s much of the time for the Model-B or a tall Corsi Rosenthal box.
I bought the same Caterpillar air blower 4000 CFM. Which speed do you normally have it on? The highest (4)? Thanks again!
Thanks for buying the fan! I does help the channel a lot.
Typically I run it on "4" when I am working but it is fairly loud. If you want to run it in the background, when there isn't too much dust floating around, the other levels should work nicely.
Don't ever do that on a table saw
Lol, yeah. I've heard. I'm much more safe with the saws these days :)
So, received the fan you linked in the description that you used in the video today. However, it is NOT a 4,000 CFM fan! It's 2300 cfm! Was your link incorrect?? It's still a higher rated unit, at least I hope it will be, then the mid-range WEN I was going to buy. Granted the vid is 2 years old, and no where on Amazon's description or CAT's description does it state 4000. I have it now, I have the filters, so we'll make it and at least I'll have something.
CAT by CATERPILLAR HVD-14AC - 14" High-velocity Drum Air Circulator Fan. Same model as in the video.
That fan was never 4000cfm. It "moved 4000cfm". They may have just updated the packaging to something less outlandish. Also, the amount of air that goes through the is about 1340cfm. That's what this video is about.
The model number is identical to the one in the video. If you have a watt meter and the fan pulls 130 watts it is the same as the one I tested.
Hopefully it will work well for you. It always has for me.
USEFUL, INFORMATIVE, PRACTICAL, AND FISCALLY CONSCIOUS.
This hits all those important boxes. +Subscribe
Dope. More on the way!
fan direction is intriguing. I wonder why most all suck air through filter if the system works better blowing duct through filter?
In general blowing air out the top creates better circulation through a space, thus improving overall efficiency, especially when the filters are dirty. Blowing air into the filter box is great for sucking dust away from a workspace, but that's generally where it performs best. I'll do a video on it early next year to discuss it in detail.
We want the airflow lies video
At this point I think that title might be to harsh. Floor and wall fans are not technically designed to work in a ducted environment and their airflow ratings are therefore inaccurate when applied in that way. I've put a ton of video together and run lots of tests for a new filtration series. I'll have these out over the next 2 months or so. First one will hopefully be out this coming weekend!
Axial fans are optimized for volume. Radial fans are designed for pressure (or resistance). Mixed flow fans hit the sweet spot in between which is ideal for your filtration needs.
You can see this in your CFM drops with filtration added. You're wasting over 50% of the air you're shifting with your DIY solution.
The ideal fans for you IMHO would be the Soler Palau td silent series which work well even with a little resistance. You don't want to be blowing dust off the floor and making so much noise that you cause more trouble than you're out to solve!
It's also nice to pre-filter air hitting the fan for longevity!!
The Soler Palau td silent series seems like a great option for keeping the workspace quiet. Most of these fans a noisy on high. But a $500 price tag on their 1050cfm model with 30% less airflow than the drum fan (with filters) in this video is a steep price to pay. If affordability is not the issue, the mixed flow fans might be the way to go.
I really enjoyed your video. Question, on one part of your video you show dust flowing into the filter. then you show on another part of the video dust flowing into the fan first. Also, if you are spraying in a homemade paint booth, wouldn't the filter protect you from possible fire?
Thanks! The drum fan is reversible. In general blowing air out the top of the filter is best. In some situations, like close to your work bench, blowing air into the filter box can be better. I prefer this method because of the way that I use it.
I would only use this type of filter as an infrequent paint booth for very small projects. It's not designed to be heavily used as paint booth. Paint booths require a very different design with lots of air flowing out of the building. If you do use this filter as a small booth, you also need to have very good ventilation to remove the fumes from the area. This filter will not remove the solvents/VOCs in the paint, only paint particles. If the area is not very well ventilated (lots of fresh air in from outside), there is a fire risk!
How many CFM is the orange fan? I have same one from home depot ans when I checked online is showing only 1600 CFM.
I tested an older version of this fan and I can not say for sure that they are identical to the new ones. If it is, this video has all the data on it th-cam.com/video/KobogQMf_Xc/w-d-xo.html
It's the strongest drum fan that I've tested. Attached to the filter box it should produce about 1400cfm of filtered air.
is there a version of your DIY rosenthal boxes that I can mount to the garage ceiling? floor space is limited... Also, I only use tools / create dust when the garage door is open -- is it still worth it to run a box like this during the cuts? Does it help to run it overnight when the door is closed, or is that too late because by then the dust has settled from the air? Thanks
I will have a design coming out that makes it a ceiling mount possible but not ideal.
A custom solution might be best. The filter clips in this video would make changing filter easy from an elevated position.
You could set the fan on a timer to pull dust out of the air for 1hr after you leave the space. There wont be anything to filter after the first hour.
Sweet video, any chance in doing another indepth review on a welding fume hood that is mobile and stuff...
Thanks!! Cheers!!
Thank you! I do want to do something like that in the future but don't have the time at the moment.
Is having wood around your workstation an issue? Would the hood have to be sheet metal?
I followed a TH-cam dust-collector design that didn't require building a support structure. It uses the same Caterpillar fan which simply sits directly on top of a canister filter. I've performed some tests on this system and the results are underwhelming. Your system has a much larger distance between the fan and the end of the structure. Do you think that the added distance between the fan and the structure helps?
I am planning on testing that design in an upcoming video. It's great to get some feedback from someone who built it because a lot of people have asked me about it.
I imagined it would be underwhelming mainly because axial fans are not great with high static pressure and the moment the canister fills with dust, it will be difficult for the fan to move an adequate amount of air. Basically, it will get choked off and not function properly very quickly.
The hole in the top of the filter is also smaller than the rim of the drum fan. This also restricts air movement.
You are probably also correct in your assessment. The more closed in the fan is, the less space there is to develop an air column that can be pulled efficiently through the fan. Hopefully that makes sense. I also think this issue affects some other designs out there on youtube.
Sometimes blower fans and inline fans are better for some designs than axial fans. My drum fan (axial) filters are designed to maintain next to zero static pressure so that the fan can function more-or-less normally. For the Wynn canister, I think a inline fan is a better option.
I'll be testing a lot of new concepts in the next few weeks that use the parts you bought in a more efficient way.
I've ordered parts to build an air purifier. An uzman ksa-400 fan (200W), and a 405x405mm filter stack consisting of a prefilter, activated carbon filter and hepa (filters 0.3um at 99.97%) filter. The entire stack is 125mm (about 5"). It's for those times that the air quality is bad or pollen is a problem. Mostly fire wood smoke, diesel exhaust fumes (rural area with lots of tracktors and trucks), ferillizer etc. Especially around easter, my neighboring country Germany light fires (garden wood etc) nation wide which often blows over my living area. I have a hard time breathing during those times and avoid going outside. It can last up to 3-4 days depending on wind direction. Hopefully this will help getting some clean air inside despite the outside conditions. I can also use it when I'm soldering electronics, woodworking (cnc, sanding etc).
I've ordered enough materials to build 2 of them and/or experiment with differen configurations.
Sounds like a good combination of parts. I hope it helps come fire season!
Is that true about the amazon link? I got about a thousand dollars worth of crap ready to order for my shop in my cart! I got you, bro!
It's true alright. You are a legend!
how long do the filters last with normal use?
You are correct when mentioning the long tunnel for allowing air to stabilize before reaching the fan.
It's called laminar flow Vs. turbulent flow. TLDR laminar flow it's like a quiet in-line fast flow stream of water (air is a fluid), and turbulent flow is chaotic, noisy and non efficient.
I've built my own filter for my workshop and have done some research beforehand, and from what I can remember the minimum distance between the filter and the fan should be 10Cm (4" in _Freedom Units_ ).
Nice video and keep those fingers away from that saw blade, *yikes* !!!
Good terminology! Do you know the scientific reason why the filter and the fan should be so close?
Blowing into filters and similar loads like heat exchangers is not recommended, it's always preferred from a fan performance standpoint to draw through. The airflow from the fan outlet is turbulent and very directional so you'll get poor distribution, load the filter unevenly and get unpredictable airflow when you compare with the stated fan curve.
The comment about fans being tested with ducts in the way you think of it is not always true. If you look at a datasheet for an industrial fan it will have a fan curve which tells you the flow vs static pressure in a standard test configuration, thatc configuration can be any combination of ducted or open inlet or outlet. The fan curve should have small diagram with it that tells you how the fan has been tested. Most of the time the way the fan is tested will correspond to its intended use. A fan designed to be used in a ventilation duct will be tested ducted inlet and outlet, a computer cooling fan will be tested open inlet and open outlet.
Good thoughts! You are correct in that the wear pattern is not even when the fan is pointed into the unit. 6" from the top corners of the filter is more clean than the lower portion. From the standpoint that it is not acceptable, I will disagree in this particular scenario. The fan's performance is virtually unaffected due to the extremely low airflow through each filter. The average filter handles only 20% of it's maximum capacity and at the bottom of the filter where the wind speed is highest in this configuration the flow is at 60% of it's rated capacity (based on 3M MERV 13 specs). I would think that if there were only 4 16x20x1 filters in this unit, the acceptable thresholds for the fan and the filters would be breached, but that is not the case.
I was stretching things a bit with the test stand info. There wasn't much that I could find and I was leaning a bit to much on the info from a commenter. The fan curves for industrial fans, specifically blower motors are easier to come by, but box fans not so much. In the end if the fan is used in a DIY filter box, it's helpful to know how it preforms in that scenario vs. a test stand.
I am working on a new video that tests air filters against one another and I tried to improve my test stand by lifting it up off of the ground for more free air flow. I can only test these on their side as the my wind tunnel is taller than the garage I am testing in. Hopefully this gives more realistic results. Performance has climbed a bit but no more than about 10% over the testing done for this video. What I figure is that if the filter is pushed up next to a wall you can expect a 10% performance drop and 20% if it's close to a corner.
Thanks for the comment! I will try to work in a correction of some kind into to the next video!
Looks like there is a fabric wrapping over the filters. Is there? And if so, what is it? I don't see it in the parts. I am asking because I am going to construct your design myself.
Awesome. That's a good question on the mesh. It's hard to find the exact right option on Amazon. I bought my fabric from a fabric store. I just looked for a non-stretch synthetic mesh fabric material that has holes that are about .5mm wide.
This is the most similar material but the sheet size isn't quite right and the price is high amzn.to/3b3B6Oy
This material is the right sheet size but the holes are to small and would reduce air flow. It would keep the filters more clean for longer tho.
amzn.to/3OAGxT1
Let me know if you end up getting one of those and how they work!
With the fan blowing down into the filter chamber, doesn’t it kick up the dust it had already previously trapped?
I'm sure it does do that inside the filter chamber but the incoming stream of air is far to powerful to allow any of it to escape. Any of that dust would just get trapped in the filter again.
Im trying to decide if I should use furnace filters vs some like a Wynn filter. Any thoughts on why you chose furnace filters?
Excellent question! I am actually experimenting with canister filters including the Wynn at the moment. MERV 15 is as close to HEPA as you can get for the shop and that's nothing to turn your back on. The unit in this video (now called the Model A) can actually support a inline fan system that has a lot of benefits, especially in a 100-200sq.ft work space. This setup allows for a large canister filter to be inserted into it without any modification (I need to check the CAD for this, I know it's possible with the CNC version but I'm less certain about the downloadable design). I will be running these designs through the same smoke test that I did for the other HVAC filters in one of my last videos.
I've started to add to this page the current results from testing the3dhandyman.com/what-is-the-best-air-filter/
More results to come on that list in about 2 weeks after I finish the latest round of testing. These tests will include canister filter tests. I have modifications for the Model-A and Model-B that make use of a second layer of filtration with the addition of the canisters. I also have a pre-filter video in the works where you can add a 3rd layer of easily vacuumed surface to your filters for extremely long life, low cost, heavy dust collection. Canister filters are great, but they get dirty, very fast. My aim with the next video series is to design an air filter ecosystem that makes the $300 Wynn last for years without cleaning.
I have been extensively testing these new designs in a heavy dust environment and I've been able to really dial things in just in the last few days. Ducting the air away from the filter seem to be a real game changer but there is a catch or two to the setup. Videos will be out as soon as possible on all this... but that might take 2 months at the current rate. I know that's a long time, but I assure you, it will be worth it.
Spent 3 years I. A commercial cabinetry and furniture shop and dust collection physics and mathematical formulas can become wildly complicated quick. Nice video and use a push stick always
You ain't kidding. It easy to have a lot of power loss throughout the system. I've been working at a small sized woodshop and the massive dust collector is only putting minimal airflow through the ports by the tools. So many leaks and bends!
do you have plans for the beastie boy? what's the difference with that one vs. the tall one? I'm gong to build one. just got a CNC and even with vac it's dusty.
I don't have the plans yet but will early next year and will be making one for the shop featured in the Filter Kit videos. The main difference is the fan that they use. I cant say whether or not the standard wall/cage fan is all that great for the task until I test it. Generally having a ducted fan, like the one in this video is preferable.
I wans going to build this for a new shop space but the deal never went through. I think the concept might work well for your space th-cam.com/video/OhVWsnTm8iU/w-d-xo.html
A prefilter may also help make the filters last longer. I will be doing a video on this in the future.
What do you think about adding it on top of the harbor freight dust collector? The Wynn filter is very expensive for a small hobby shop.
I love the idea! Hopefully I can experiment with this some time next year.
begs also the question of electro static filters.. the metal ones that should last like 10 years
any thoughts about that one
I tested some K&N washable filters that should last 10 years or so. They preform around the low end of MERV 11 filters but the reusable aspect is a huge plus. I'll be making a video that uses them a few weeks or so.
As for the metal ones, the ones I've seen have very low MERV ratings and are only good for large dust. Got any I should take a look at?
@@The3DHandyman I've a couple of air (scrubber/ purifyer) used to help clean up the air. Family with bad sinuses and allergies that this helps. So i'm looking for custom made filters like that of particular sizes. any thoughts? would it work? or are there people who do something like this?
@@sspaceforce I haven't seen it yet. I'd like to give it a shot at some point but I wont have time for quite a while. If you want to filter the air with basic materials you will probably need A LOT of filter surface area to come close to the performance of a disposable filter or even the K&N home filters. These filters are highly engineered for the task.
The cheapest method is really to tape a filter to the back of a box fan. The 4" filters should last 1-2 years under normal conditions. For allergies a MERV 11 filter might be all that you need. Allergies tend to be larger particles than other pollutants.
True on the allergens being larger particles. That's sort of why I'd like to test the basic filter concept. For a lot of people, that might be all they need.
I have to say, this video, and more to come, are very interesting. I suspect one advantage of the "cylinder" fan relative to the box fan is that the latter has corners through which airflow can return around to the intake side. Also, when you connect a fan to a duct, that duct creates some resistance to airflow, so the resulting flow rate will be less than for the unducted fan, possibly explaining your noted discrpancies? Indeed, if your tests include a measurement of the pressure generated by the fan (or vacuum for sucking), that would result in much more meaningful comparisons between fans, and between filter arrangements. Hmmm, I can't help feeling this is probably already a topic of study by home-filter-builder enthusiasts :-).
You are definitely right about the the cylindrical housing around the fan helping to improve efficiency. I will test a Corsi-Rosenthal filter in the next video and that placing a circular cover over the box fan does increase performance.
I was thinking that the duct likely plays a role in the numbers I'm getting. This is the industry standard for testing but the pink foam that I used may create an undesirable static charge in the wind tunnel that could slow down the air. There are also other factors as well but I will get into those in the video... still trying to collect my thoughts.
Testing static pressure would be a nice addition to the video but I'm not sure how that would work in a system that is not a closed loop like an HVAC system. I will look into that.
Thanks for the comments and ideas!
i think to better capture the true air speed from a fan, the tunnel should be at least 1 ft wider than the fan to eliminate as much boundary layer as possible so that the centre of the tunnel is closer to the real world air speed without boundary.
For the latest pass on this I used 2 anemometers inside of the tunnel to get a better representation of the real world speed. You are right about the boundary layer though, air at the edges does move more slowly. It's tough making the prefect wind tunnel for each size of fan, so I may just settle for a good test rather than a great test.
At this point I am also more focused on finding out which filter preforms best will smoke and other super tiny particles. I will be showing CARD number for all of these some time soon. Air speed is a big factor in filtration but there are more variables to consider when finding the best design for your use case.
Looking to build your 4000 cfm fan. Have you measured the decibles of the fan at 4000 cfm (real world)?
Yes, here is the sound data for all the fans I've tested
Background sound 40db
Lasko @1ft - 63, 60, 55
Air King @1ft - 68, 66, 61
Air doctor HEPA @1ft - 64, 58, 52, 45
Maxx air @1ft - 71, 67, 57
Caterpillar @1ft - 71, 67, 63, 57
Do you have a build list for this? Also, any reason you ahem the fan blowing in rather than pulling through the filters?
Yes I do, here's the build th-cam.com/video/fixd7LqnWow/w-d-xo.html
For what I'm working on at the moment having the air blow in to the filter helps to keep local dust down at my workstation. If I was working with tools that are more likely to blast dust out into the room, the "pull configuration" might be best. The build video goes through some tests with this. Overall the "push config" seemed to yield the best results.
Thanks for the comments!
This is amazing an thorough.
Would these reduce pet odors?
Thanks! Yes, they should reduce dander and pet hair which are a big contributor to the smell. I will have a video with some modifications to this design that use inline fans as well. You can run a duct to the them and install a huge charcoal filter on them to further eliminate smells, but the system does get pretty large at that point.
Great videos. Do you know when your next one in the series will be published? What type of fan are you using in the "compact" and "beastie boy" units you preview? Do you have plans for them you would be willing to share?
Thanks! The video for these new units will take 2 weeks or so for me to get out. The construction style will be identical to my floor model filter so watch that for general construction concepts. I will be making a version that uses only plywood as well. Hopefully I can get those drawings done tomorrow.
Plywood/2x4 Construction Drawings:
the3dhandyman.com/workshop-air-filter-series/
Here are the Fans and Filters I am going to use:
24in fan for "beastie boy" 5850cfm
amzn.to/37q96CV
merv 14 filters - 20x30x1
amzn.to/3vSWQnW
18in fan for "compact" 3190cfm
amzn.to/3kS9YmS
merv 14 16x25x1
amzn.to/3w9r98R
There are cheaper fans out there but I am trying to source fans made all or in part in the USA.
Here is an "8800CFM" version that is not USA made. I can not possibly imagine that it is capable of producing anywhere close to 8800CFM. It is the same size as the TPI fan but has 20% less horsepower. This one should work fine with "beastie boy" but there are no posted dimensions, so I can not say for sure.
amzn.to/3ymA6hV
Not sure if you will get a notification for my edited comment, so check out the last comment for the link. Let me know if there are any issues.
@Jason Shapiro
Hi Jason. Sorry for the delay getting the next videos out. I'm currently working to fulfill order for the mushroom castings that are featured on this channel. Hopefully the next videos in this series will be out in the next few weeks 🤞
@@The3DHandyman LIES! Lol. Just kidding. :)
Looking forward to the next video on this!
Lol, yeah. I need to give this some time but the workload the last 2 months has been off the charts. The next video in the series is filmed but I need to cut it together. The builds will take until next month. Sorry for the wait, and thanks for your patience!!!
Although you like pull mode, is there an advantage of pull vs push.
Good question! The air coming out of the unit is at a much lower velocity in push mode. That allows for better local circulation and a reduction in fine dust being picked up in the fan's wind stream and deposited all over the shop. This works great if you are working right next to the unit and not throwing dust at a high velocity in the first place. If you are using a saw or grinder, etc and the dust is already flying, pull mode is fine for filtering the ambient air as any standard air filter would. Push mode is not going to move air around the workspace quite like pull mode does.
Hope that clears things up 👍
Can you run the filters in series so a lower HEPA filter picks up the bigger particles, and is backed up by a higher HEPA filter. That would decrease the need to change the more costly higher rated filters? You may have already addressed this, but I could not find it.
You most definitely can do this. Technically the term HEPA is reserved for HVAC filters over MERV 17. So if you are using a HEPA filter, it should be the last one in the series. Before the dust reached the HEPA though, you can use lower MERV filters to filter out a lot of particulate.
I will be putting out a video on this concept next month. In it I'll show off a new setup for the filter in this video (now called the Model-A) that allows for 3 layers of filtration and more.
@@The3DHandyman Thank you for the rapid response. I really enjoy your videos, especially the scientific break-down. Looking forward to seeing your next one.
Is there a reason you didn't add another filter at the bottom would it reduce the air flow? or increase?
Good question! After the last round of tests, I think I can confidently say that an extra filter on the bottom would not change the output of the device. There is simply not enough free air underneath the bottom of the device. It's likely that 95% of the air that would be pulled in through the bottom would get pulled in through the side filters.
The 4 and 5 filter (one on bottom) corsi-rosenthal designs I tested had the same output unless the 5 filter design was raised at least 3 feet off the ground.
AMAZING VIDEO
LOVE THE NEW VIDEOS
Ah very nice / okay I appreciate the great videos !
I take it this video answered your your question :)
Glad you are enjoying them! More air filter content on the way, including a video about this concept specifically.
@@The3DHandyman Thank you very much. I am building a 12" version of this. also a seprate project of using a 4" duct + duct fan, to draw the heat out and away from my PC witha custom boot/hood that fits over the top of the system. kind of a cool idea
@@TwistedLogicGaming I am working on a desktop edition of filter and I love the idea of blowing the filtered air into my PC. Maybe I'll make a video on the PC cooling option at some point!
Really, really awesome! 👍 Thanks for investing the time to gather all this data and information then sharing it with us. I'm "blowing"💨on over to your next video! 😂Take care and have a good one, Adios!👊
Thanks for watching! I'll have a new series on air filtration out in a month or two. I just need to find the time to work on it! Then some day I'll make more non-air filter videos 😎
@@The3DHandyman I'd like to "clear the air", I see nothing wrong with this content, it is such an important topic. Sorry, sometimes I just can't help myself. 😉
Isn't the push confirmation a pain to clean the inside of box? Or am I missing something.?
You don't have to clean it ever. At least I never have. The dust gets stuck to the filters and you just throw them away. I collected 1lb of ultra fine dust on the 8 filters before air flow dropped noticeably.
If you run the fan in the pull configuration then the dust builds up on the outside of the filters which is arguably worse because you can knock it off if you bump into it.
I'll do a detailed video on just this concept some time.
Top notch information! Thanks
Great job and very nice of you showing the plan how to make it - keep up a good work
Thank you!
Do you think the fan matters that much? ie could I use my 30in harbor freight fan (6500 to 9540 CFM) in a modified beastie boy?
Most fans are pretty much the same, so anything goes for that type of design.
A good rule for filter sizing might be to add about 5 or 6in to the diameter of your fan. That number will be the long side of the air filter. For the base beastie boy design the fan is 25.5in wide and the filters are 30". If your fan is 32in in diameter then the ideal filter might be 38"?
Do you think a furnace blower is better than a regular fan?
Did you design any other layouts for this yet? Like a ceiling mounted one?
I have not but this design as it is can be mounted to a ceiling. There is a new 4 filter design that I haven't made a video on yet. It's pretty much the same as the 8 filter design, just a bit easier to make. Plans are here the3dhandyman.com/diymodelb/
Thinking about building the ceiling mounted versions and hanging them from my 92" garage ceilings (kinda low). Just looked at the plan and it looks like the fans are pointed up (towards the ceiling). Wouldn't it make more sense that they're facing downwards, where there's a greater volume of air to pull in?
Good point. The extension legs could be mounted on either side. At the time I made this I hadn't made any printed parts for holding the fan in the sideways or upside down configs. I just printed the first batch and I will have them available for download/ purchase on etsy by this weekend.
With these you can make legs or just screw the unit on to the wall and go with 6 filters. The performance would be reduced a bit but you would probably still get 800-1000 cfm and save some floor space while you are at it.
The clamps are now ready for download. I should have these ready to buy this weekend.
Print link
www.thingiverse.com/thing:5501226
What would happen if your caterpillar configuration included another fan at the other end of the filter box? A push/pull configuration.
The fans would both need to be pointing out or pointing in for the air to be filtered. A push/push or pull/pull config. If you did either one of those you should add a lot more filters to accommodate for the extra air flow. Double fan, double filters would be good. That would certainly filter a lot of air! You could also run 2 separate filters and accomplish the same thing, tho.
I hope that answers your question!
@@The3DHandyman OK, thanks!
I wish a pulmonologist would chime in and explain how dust can cause nodules in the lungs. People tend to think if they aren't coughing when they encounter dust, there body is handling things just fine. Unfortunately, that isn't how it works. Wear your dust masks folks, and get something / build something that will eliminate the particles from the air when possible.
Good thought! I would have to say that despite all the air filters I run, if I'm doing something dusty, I always wear a mask.
@@The3DHandyman I went to a pulmonologist and he showed me my x-ray and I thought I had cancer. I had nodules all over my lungs. He said "did you grow up in a dusty environment?" I thought about it a while and I realized I used to ride dirt bikes as a kid and it was always crazy dusty. He said well that will do it. Will those nodules turn into cancer? Who knows, but if I knew then what I knew now I would have been more careful. Every time I see a video like yours I really appreciate what you are doing showing people how to filter the air so their lungs dont have to take the brunt of it. Especially when you are sanding on man made materials with bonders...
@@MrBobbybrady I hope those stay benign! Scary stuff. I appreciate the comment. Stay safe and healthy my friend!
How big is the smallest sawdust particle?
The internet says that they are between 10-30 microns on average, however using an air pollution monitor around a saw will show particles from 10-.03 microns as well. My newest video is about filtering super small particles. I will also make a video in the next month or two about adding pre-filters to capture most sawdust and help extend the life of your more expensive filters.
Thank you I am building one of your designs.
Awesome! Any one in particular stand out to you?
have you looked at the Wynn filters. they are merv 15, and cleanable. at a good price.
I have not! Thanks for the idea. Do you have a link? All I'm seeing is MERV 8s
I just got 4 K&N washable filters to test but they only come in at MERV11
I found the video you are talking about! He didnt say the cfm output but he did put an anemometer on the outflow and the Wynn+Ducted fan design appears to put out 500cfm on the dot for about a $350 price tag. MERV 15 and cleanable is a huge benefit but I think I still prefer the higher airflow.
What do you think?
Did you end up building a filter for the fan motor itself?
I did not. I've switched over to the Caterpillar fan exclusively thanks to the enclosed motor instead.
Can't wait for the next addition to this series and seing the other versions in use
Thanks I will have the next video in the series out in a week or so. I hope to test the other versions next month!
The industry (at least in EU) usually use HEPA filters (MERV 17 and above) and because they use these filters, they also need to use centrifugal fans to create enough pressure to actually pull enough air through these filters. You totally ignored this aspect when you compared your purifier to other purifiers on the market. Also, you didn't measure the smallest particles in the air. As you've mentioned, these particles are actually the dangerous part of the dust. You've maybe created cheaper air purifier, but it's looks like it's not good enough to protect your lungs from fine particles.
When I found your video I was really enthusiastic. I wanted to copy your design but with custom made filters because I don't want to rely on some replacement filters with pre-defined sizes sold online and I also want to capture more fine particles that MERV14 filters do. I wanted to use HEPA filters. So I went to a company that makes them. The first thing an engineer in the company asked me was if I already have a fan, how much of pressure does the fan produce and how much particles do I produce in my workshop. I told him about the Caterpillar fan and he told me that this is not a good fan since it doesn't produce enough air pressure and that the CFM is not the metric they need to make a filter. As I said, they need to know the pressure and the number of particles (of different sizes) in the workshop.
@@noID457 The Caterpillar fan or any axial fan is not ideal for use in high static pressure environments. HEPA filters certainly produce more static pressure than disposable HVAC filters. The work around with my designs is to reduce static pressure (with new filters) to near zero in my designs so that the fans can run as they would normally without any filters attached. It's not what an air filter manufacturer is going to choose because they are not interested in DIY design concepts.
Although airflow (cfm) is not necessarily their main consideration in designing a filter system, it is absolutely a factor in determining the number of air changes per hour. This is an important metric when determining the efficiency of the system.
If you want to use HEPA filters, Inline fans may be a better option. I have been using these for a while and I am making a few videos about them now. They are better at dealing with static pressure but are less costly and power hungry than centrifugal blowers.
You can use any fan you want for a design as long as you have enough filters to allow it to function properly. Just look at the "corsi-rosenthal" design, a manufacturer will never choose a box fan as a power plant for an air filter, but it still works well.
Here is a breakdown of fine particle removal with various filter brands that I did. HEPA will of course be better, but you will need more of them or a fan type that can better handle high static pressure, or even better, both of those things th-cam.com/video/XAJ__E-hIJc/w-d-xo.html
for a mold issue, would it be better to suck in or suck out? I have activated plus carbon and merv 13 2 inch
Pointing the fan into the frame seems to work better in houses. It cleans the air through doorways a bit more effectively. If the fan is pointed upwards then the fan will stay more clean from spores. That would be a different sort of benefit. It's up to you
@@The3DHandyman yea I'm learning more by nerding out on these videos, 2 inch will capture more dust overtime but 1 inch is more efficient with good airflow . I'm looking at the 14 inch CAT fan for killer CFM and Merv 14 if I can afford it.
I'm eagerly following this filter series! Im interested for the potential of low cost DIY air purifiers for general home use. Ive not had luck finding a fan thats ideally affordable, powerful, quiet, and energy efficient. The centrifugal fan in the Coway Airmega 400s purifier is pretty good, whatever that one is. Rated at 410CFM of HEPA processed air drawing 69 watts. The downside is the ~$400 price tag and high replacement filter cost times having one in each room.
Your videos are giving me good info.
Awesome! I was plaining on testing a home HEPA filter for this next video. I know someone with an "air doctor". Retail about $500. Apparently it's rated at 373CFM max. I'll see if it can even pull that off. You are right, I think the HEPA filter replacement is a huge long term expense.
I will also test out a Corsi-Rosental box with 4 and 5 20in filters. It's not super attractive but I suspect it will preform fairly well. Are you looking for something nice looking? That might be an interesting project.
I found this great centrifugal fan section on Grainger. I was thinking about using one for a paint booth but it could also be used as an air purifier fan. Not the least expensive approach tho. The drum fan in this video would move more air for less money but it is quite large for in home use.
www.grainger.com/category/hvac-and-refrigeration/ventilation-equipment/oem-specialty-blowers
@@The3DHandyman Yes, to save money one can utilize the washable MERV 13 air filters which are $40 per unit or $80 for two or $169 for four of them; when one considers that Filtrete MERV 13 air filters go for $23 apiece at Lowe's one breaks even quite literally at the one year mark if one changes their MERV 13 air filters every three months typically.
I'm getting my materials ready to build this. I looked through comments but haven't seen anything: what's the mesh screen you have around the outside of the unit? Or is it just my imagination haha.
Nice catch! Sorry for the late reply, was out of town. That is a .5mm (500micron) mesh screen. I just bent to a fabric store to get that. I talk about it in this video th-cam.com/video/fixd7LqnWow/w-d-xo.html
If you can go to a store to pick something out, that would be preferable but if you have to find something on line, I have recommended these 2 products before but I have not tested them myself.
amzn.to/3b3B6Oy
amzn.to/3OAGxT1
I am making a kit for this version and I hope to get a seamstress to make filter covers for the units to make this an easy addition for people. It definitely helps prolong the life of the filters
Haha, ok yeah I thought you did mention it but then I couldn't find it again. Anyway, thanks so much for responding. I love the idea of filter covers.
My filters arrived yesterday and the fan arrived today - seems like my weekend is planned!
Thanks again for all your help!
@@toddsennholtz7305 Any time. Let me know if you think the design can be improved in any way, otherwise, enjoy!
I built box fan filters using 4 inch filters instead of 1, and they seem to do the job well enough, best budget option. You can even use more filters if you want more airflow.
Extremely well researched and very well done, thank you for this! I would love to build the downdraft version - I think it would work well for flying dust from mitre and table saws. Do you have plans available for that version? Thank you.
Awesome! I don't have any plans drawn up for that one yet. I can make some for the next video but that will take a little while. There is a lot going on at the moment. It's essentially the original design flipped upside down with framed legs if you want to give it a shot. If you do, let me know how it works!
Here is a link to the plans for the "Original Air Filter"
the3dhandyman.com/workshop-air-filter-series/
@@The3DHandyman Thank you, will definitely give it a shot! Just have to source similar merv 13 or merv 14 filters in Canada. I stupidly cut some mdf boards in my basement with just basic dust collection and regretted it instantly.
@@shafror Awesome! I would love to see some pictures if you would like to send them my way.
Not sure if it is too late to ask but what is the depth of that fan? Trying to figure out if I build this exact system if it will fit where I want to store it.
Thank you!
It's not too late! If the legs are not included, the depth of the fan is 10.5"
@@The3DHandyman thank you
@@mghtymous21 Any time!
Do you have a filter box build guide?
Yes I do! Here are the drawings and the build video the3dhandyman.com/workshop-air-filter-drawings/
Let me know if you have any questions
Hello! Why is the fan not installed backwards, because then it would not be clogged with dust?
When the fan is blowing out of the filter it causes some of the local dust to get caught up in the air stream leaving the filter box. From there it ends up spread all over the shop. I talk a bit about it in this video th-cam.com/video/fixd7LqnWow/w-d-xo.html
@@The3DHandyman Do you think it is possible to use car engine air filters at home?
@@artyk242 That's an interesting idea! I'm not sure if an engine air filters comply with MERV ratings though. They are designed to be high air flow and function in dirty environments so they may not be good enough for respiration. Project Farm did a video where they tested engine filters and at a quick glance it looks like particles up to 5 microns were slipping through some of the filters tested.
If you buy a filter for a 6 cylinder of above it should be able to handle a 2000 CFM, so that check out at least.
Cabin air filters might be a fine alternative to engine filters.
What kind of mask at around the 4:30 mark?
That's called a 9205 N95 Aura Particulate Disposable Respirator. Overall a pretty good seal and comfort level. It doesn't touch your mouth when you talk. The nose bridge isn't the best after several hours of wear. amzn.to/397LCTx
Awesome to see you doubling down on the content that worked for you! Just getting started with taking TH-cam seriously and the 3D printed kits/parts for my projects was an avenue I was considering. It would be cool to hear about how well this works out for you on a monetary level and how you balance the workload of making videos and these parts/kits. Thanks for sharing!
I figured it was time. It's definitely my bread and butter over here. I'll be setting up an Etsy shop for the prints, they take a big but help reduce shipping costs. Should be interesting to see if there are any takers. In the past I referred people to Make XYZ but never realized the prices on that platform have gone through the roof lately. I couldn't believe the price they wanted for the power inverter case. Ask me again in a few months and I can give you an update!
@@The3DHandyman update?
@@j._7054 Sure! Sales on 3D printed parts have been steady but don't generate a whole lot of income. Typically less than $100 per month. I am launching a line of wooden air filter kits that I hope will increase this a bit but between the cost of shipping, manufacturing, and Esty fees they are probably going to be out of the price range of many people.
I have a lot of air filter related content on the way and the videos are preforming well but they are time consuming and costly to produce. Ad revenue at this point really doesn't even cover the cost of video production. So to sum things up, monetizing the channel at a level above "side hustle" can be a real challenge.
@@The3DHandyman i hear u. I ordered one of those "4000 CFM" caterpillar fans yesterday using your Amazon link. My garage looks forward to some much improved dust collection/air filtration soon thanks to your vids
@@j._7054 Awesome! Thanks very much for your support.
how is filters make a paint work area?
I would like to build one of those at some point. I see you are painting some car parts with HVLP sprayer. Very nice!
I once spent the day in a paint booth for semi trucks and they had a system sort of like the one I plan on building for my new workspace. Here is a 3D video on that subject. I have not built it yet. th-cam.com/video/OhVWsnTm8iU/w-d-xo.html
Over the top of the filters you should use "Paint Booth Exhaust Filters ". Google those. They are cheap but wont filter out all of the paint particles. They just help to keep the air filters clean for longer.
Keep in mind, that it's best to exhaust the air to the outside of the workspace. You can blow it out one window and put another air filter in different window to make sure you are not pulling dust into the open window. This should help avoid paint defects.
You could use the design in this video and wrap it with the paint booth exhaust filters. Point the fan up so that the air is filtered before it does through the fan. Just be sure to have great ventilation. The fan motor can get very hot when its 95F or 35C or hotter.