Tony M - you’re not the only one! I did the same thing. Built that box from the original design as well, and my box fan was too big to fit. Glue, nails and screws....and enuf swear words that Hubby came running out to the garage asking what the matter was. Had to pry one side off before the glue dried just to salvage at least half the build. Already knew that I would need to build a shroud as well and accommodated my measurements to fit that shroud out of quarter inch hardboard.... so instead of this fan working overnight to clean my garage from all my glitter (er sawdust), I have to wait until tomorrow.

Thank you!

Thank YOU for watching? Have you seen my guitar videos?

Something I learned in R&D, a time comes when a design must be taken from the engineers and sold to a customer. There must also be a balance between cost and functionality. Things can always be improved.

Thank you! Cost vs benefit is a constant struggle, and I appreciate you acknowledging it and taking the time to comment. Cheers!

And curious based on your experiences using your DIY shop air filter, how dirty does the exhaust filter get compared to your #1, #2 and or #3 intake filters? Where's most of your dust being captured?

I change the exhaust filter once every 9 or 10 months.

I agree ha

Your confidence in my mediocrity is inspiring! You are officially invited to comment on all my videos.

That "internet troll" gave him the motivation to upgrade his air filtration system to excellence. The first "mediocre" version was awesome when you have little time, limited energy and a busy life to live as It beats not building anything at all, but the second version is way more efficient. This is why freedom of speech is so important, it may create baseless "Verbal flatulence" as you call it but exposure to it pushes creative people to outdo themselves.

@@FranklinWoodWorks2016 Bill Gates said he would always hire lazy people as they will find a faster more efficient way of doing something because they don't want to put forth the effort. (Paraphrasing)

Franklin, you're doing a great thing there. I don't have time or money for a fancy air filter, so I taped a 20" filter to a box fan. Big difference in air quality! I applaud you for upgrading yours for your own health. I will too, when I can. But, I urge you not to listen to those negative people out there. That's a kind of pollution that needs it's own kind of filter 😉

@@MAXAREUOS *bump* I had to comment, because you have explained adversity and its usefulness in human growth and learning. I just really appreciate seeing this in the world. Thanks :)

Richard, the difference is astonishing. I plan on doing a "shop update" video as a followup on some of my projects, and I'm going to include the improved dust filter. And, you have no idea how much I appreciate your support of the channel.

He got 15-20% improvement by taking the advice of the "trolls". Sounds like a good deal.

Utilizing the Bernoulli Effect increasing airflow

"I am...inevitable." Thanos

and even more by using the vortex the fan would create in such a circular duct to generate double force. so basically using a circular duct makes it more efficient because the air coming out of the fan can rotate freely the way it wants and doesn't get to much turbulence due to inbalance in the shape, a square shape would cause a lot of inbalance since the rotating airflow from the fan would need to make angles of 90 degrees which is inefficient and creates huge amouns of turbulence. there also indeed is a small part which comes directly from the changing of the volume of air since in the places where it goes into the fan and just behind it that would also generate a sudden increase and fall generating a lot of turbulence, however on the contrary something is also true. the bigger the area of the filters you use the less friction they give, and that would be a rather significant loss. so we should want to keep the parts where the filters are mounted nice and big and square in the shape of the filters. but to optimize the airflow and not waste the energy from the vortex to turbulence the fan itself should be inside of a circular pipe around 3 times the length of the fan, but more is possible. and to counter the vortex twist before it hits the square part and to convert that twist into a airflow and pressure boost we should add fins in the circular shape just a while after the fan, not to far, not to close, to far and you lose energy, to close and you also lose energy in pulses, in general keeping around enough space for another propellor in between should work well. those fins should be aimed in the opposite direction of the fans blades. if you first measure it and calculate it you can calculate the perfect angles and such. but right now we can just make them the opposite angle of the propellor blades, or since we run it at a low speed and pressure we can make them less steap and more in the direction of how we want the flow of the wind already, that way we can be sure they aren't to steep and so they won't cause a restriction in air flow, and ofcource these blades are connected to the outside instead of inside, since this is a low pressure and speed device we shouldn't go all the way to the middle, we should also use as thin as possible blades for this, since they don't need to move anyway and only need to steer the wind. while just simple blades are enough, if we want to be sure of high efficienty we can make those blades bend and slightly go through straight with the desired wind direction until the air exits the circular conduit. now that should when done right double the airflow and/or pressure for such a fan when you run it on the same RPM which would greatly decrease noice and also decently decrease power usage. but we forgot one thing and that is where the filters are. this system has one filter in front of the fan and a few behind it. this means that we should add some extra space in front and behind of the fan to make that transition from a big square to a smaller cylindrical conduit, since the airflow isn't to big in that system the intake side doesn't need much of such a smoothening transition, it is just to prevent the turbulence from that 90 degree angle. so we can make it around 45 degrees or less steep, with one exception which I will discuss later in this. on the exit you want it slightly bigger to make sure the transition from round to square, and from small to big are smooth so it won't cause turbulence. both on the inlet and exit this can be done with a specialized plastic or metal part, but it could also be done with duct tape, with wood if you are capable and willing to finish it decently, or with a material like tempex, which is probably the most simple option, you can add some tape or plastic over it to make sure it doesn't get damaged to much over the years, but it should keep up just fine since it has been used more often in such things, just make sure to cut it with a hot wire or such or to use something like a hot plate or hot air gun to make it smooth where it will touch the air. bare tempex also brings a advantage and draw in one since it likes to accumulate a static charge, and a strong one, when you keep blowing wind past it. this static charge will work as a filter for big and insanely fine particles, however it will only filter around the outsides close to the tempex, luckily due to the vortex most dust will be in the outsides first, however remember we canceled that vortex out to get more efficiency, so now the dust will spread more even through the system. luckily this tempex part is close enough to the cylindrical conduit that most dust will still be on the outsides, and on the top we should mostly see specifically the super fine dust which normal filters won't capture making it a nice extra filter step. but there was a draw, and the draw is that the air also gets a slight electric charge, this means it will be atracted to it as well which causes some friction, luckily this frinction is insanely small, especially at these low speeds, so the friction due to this should be comparable to the friction due to the inconsistency in the wood, but there is another draw, and that is that tempex likes to stay static, there isn't really a easy way to rapily make it non static, which means it might be hard to clean of all the dust from it. again all over the draws it has are mostly draws to the pros, and the prose can be quite nice, so using tempex for such a low speed system would be great. but I said I would come back on something and that was for the inlet, right now we altered the inlet to prevent losing airflow, however we can actually use that same size difference with a altered inlet smoother to gain extra windspeed. to do this we just need to make some kind of duct like a ducted fan. this way it will work like a airfoil, this will increase the tota airflow and will also prevent some of the air which tries to come back using the outsides of the fan. but again we don't want to many sharp edges in such a system, so just around the edge of that duct we again add something to even it out and prevent those sharp angles. normally that wouldn not be a problem if the size difference was big enough. but right now the square is only a little bigger than the cylindrical conduit, so we get more efficiency by also including that smoothening.

😮

That's a great idea.

Lloyd you and I would likely be good friends / neighbors, no harm in learning is a good and constructive position in life. Iv'e been doing woodwork for 55 years and continue to learn things everyday as well as make plenty of mistakes. But I would correct what you so nicely said " passive-aggressive" no no not passive in any way but just down right aggressive arrogance coming from the opioids of their own prideful brain cells. Hey I'm just saying! lol

Bill Smithem same here!

Me too, but there is a lot of turbulence in the corners. The baffle is supposed to help with that, I’ve been told. Not sure what the big box accomplishes. Might try it and see. As for the mediocrity comments, 80 years on the rock has taught me that perfection is in very short supply. Make something that works and get on with it; we’re burning daylight here.

Stuck a filter on my dehumidifier. Think I'll stick one on my box fan too, just run it when I'm not home.....copd ... btw pretty sure the Correct quote is"religion is the opium of the people", Karl Marx .

I taped a furnace filter to a 20” box fan as a temporary air filter until I can build a unit like this. It worked but burnt out the fan the first day, so I am a little apprehensive to build a unit like this.

@@Donski96 Interesting. Mine has been working just fine for three years.

I think your right but would the box begin to swing slightly from the breeze it creates or centrifugal force? I'd prefer that box being secured if that happens.

or how bout L brackets on the side so it can be secure.

I don’t think there is one.

Well then you're wasting your time here. This is a NO KILL ZONE. Franklin is just, thoughtful, innovative, inexpensive, straight forward, no BS, works as intended and a damn far cry from mediocrity.

It would be great if you could show us some of your exemplary competence. I hope you understand that we would be justified to be as sharp with our judgements with your work as you are here. How are you contributing to this being a "competent" solution? Be a man. You are just envious. Richard is doing something useful. You are just bickering.

I don't have any plans for version 2. But, the dimensions for the pieces will be based on the internal span of the box and the design of the particular fan you use. I bet you can do this.

Or for less the 50 dollars more he could get another air cleaner. Wow.....

@@SW-zu7ve I don't believe you can buy an effective air cleaner for $50. A particle meter is worth the investment for anyone who wants to take healthy air seriously. The particles that are most dangerous to your health are too small to see so without a meter you are just guessing. For example, I bought a discount air filter that was rated as MERV 12 (relatively high filtration efficiency) to save some $$. I tested it and it was filtering at closer to a MERV 6 filter which essentially passes 95% of the most dangerous particles straight through. It still got dirty and filtered the big particles but those aren't the ones that get deep into your lungs. If he uses a MERV 11 or equivalent filter then this system will effective. However, a meter is great for figuring out what does and doesn't work for mods to dust collection ports or to see if your dust collector filter is cleaning the air or actually making it worse which is the case for many types of filter bags. A meter is cheap insurance (awareness) for a slow killer. Long term wood dust exposure isn't much different than smoking. Over time it has very similar effects.

@@SW-zu7ve I think Jose had you in mind when he wrote his comment.

@@markw3598 And what verbal flatulence Mark? Did you even read my comment? Do you even know what I was commenting on? Do you even know who I was commenting to? Anyway I think you just trolled me.

@@shophacks Where did I say 50 dollars gets you a good air cleaner? I said ADD 50 dollars meaning to the 150 you are saying to spend. So 200 dollar will get you an adequate air cleaner.

Agreed. But wouldn't that really impact the cost? Remember this is for a wood shop, so I think the gain in efficiency would be offset by the increased cost.

FranklinWoodWorks Well because there is less pressure drop you can filter the same amount of air with less electrical cost. The motor doesn’t have to fight so hard. Although because the airflow will be higher at the same speed setting it will draw more electrical current. So it depends on how you’re running it. The filter cost would be less. Just for a quick comparison I found “Aerostar” brand filters on amazon. A MERV 11 1” is $5.55 and the MERV 4” is $7.71.

Since the airflow is higher you could run it less and then you’d save on electricity with the same amount of filtration. Likely with how cheap the electricity is on this you’d just run it the same and it’d filter quicker. I’d imagine the money saved on filers might offset the electrical cost. Although I might be even more inclined to this since I can get the filters wholesale for about half price. 🤫

If you haven't seen it, watch my video (shop lighting upgrade) that will show you why I use the lights I have. There are so many great options out there now, but I think I was able to save many $$ with the approach I took.

You, sir, have won the comment of the month award. Folks that subscribe to my channel seem to have figured me out well enough to know that what you see me making is generally the first time I've ever made it. No testing, no rehearsal, what you see is what you get. That being said, my goal in all of my videos is not to show you that absolute best way to do something, or the best design, or the best anything (although some of the titles may lead you to believe otherwise). It's to show the viewer something new I've discovered, or a different way to do an operation, or to make something yourself (tools, jigs), saving a ton of money while accomplishing the same thing. I also never publish plans. Although the Sawdust Maker made plans for this original build, if I look at plans, it's only to see how a thing is made. I make the dimensions my own to fit my needs. I expect most DIYers would want to do the same. Plus, I want to inspire others to use their brain, think outside of the box, and get creative. Thank you for your encouragement - it was well received, and sorely needed.

Don't think so. Matthias Wandel did a video where he experimented with baffle placement. Wrong placement will actually make it worse.

Half inch ply wood be fine. I used 3/4 Baltic Birch because 1. that's what I had in the shop, and 2. I'm well known for over doing things.

Whoa brother, I may be the worst person to answer that question. That being said, I would think the main issue would be to get the air to the fan without the dead space that a rectangular enclosure creates with a round fan(s). If you can create a baffle that fits the fan(s), then it will be fine. And, I'd also think that the more area you have covered by fan blades, the better, although it would be dependent on the efficiency of your baffle system.

It's not a dust collector - I have that attached to all of my tools with the exception of my lathe. But even with good dust collection, there is still fine dust that gets in the air. That's what this unit is for. The idea of multiple filters is to cut down on cost. With several cheap filters with low MERV numbers, I can replace one cheap filter a month ($1) by rotating them as opposed to one expensive filter per month ($20). It's simply a cost saving measure.

I didn't, but I relied on Matthias Wandel to do it for me. He experimented and found that the baffle should be just slightly forward of the fan. I mounted mine where most of the blade is slightly forward of the baffle.

Very nice of you to say. Thanks for the info.

If you look carefully at 2:44, you can see that the blades are in fact, right in the center of the baffle. The camera angle may be misleading. What you see about one inch behind the blades are the motor mounts. The one inch spacers I talked about in the video is what allowed me to put the blades where they needed to be. Apologies if all of that was confusing. It's difficult sometimes to write a script explaining things since in my head I know what I did. That last sentence was probably confusing too.

She's a BOSS!

Well it would be, but then I wouldn't have been able to build t out of scrap. Remember, this wasn't about the best design possible, it was about the best design possible with what I had on hand

Good question. I've actually done some research on this. The best solution is to get a really efficient fan, like a squirrel cage fan. Those things can really move some air, but unless you can salvage one from somewhere, you're going to pay. But, that's not what you asked. Based on my research, if I had two box fans, it would be much more efficient to use them separately - increasing the surface area of your filter materials by 100%. Putting the two fans in series (one in front of the other with both blowing in the same direction) will get you about 25-30% increase in efficiency, but you'll still be stuck with the same filtering surface. How all that works out mathematically is way beyond me, but it would appear that two fans working separately would be more efficient.

I wondered about the filter in front also. I agree with you Sashimi-X that's probably a wasted detriment instead of a help?? I'm also wondering if you had more surface of filter....like a box with 3 sides (with filters on the 3 sides), wouldn't that give you better filtration (more surface area) than 3 stacked in series?? Or at least filter more air volume faster??? Don't get me wrong Mr. Franklin, your project and ideas were excellent and quite honestly I dunno nothing about woodworking compared to you, I am just inquisitive and asking opinions. If I do something like this it will take me forever as sorry as I am with woodworking, that's why when I do it I want to do it as good as I possibly can. My concern with my idea of putting 3 filters around the outside tho is ......can you make the box strong enought doing it that way??? It might be best to give up the 3 side filter box for Sashimi-X idea with your basic theory. Any comments would be appreciated.