Air Filter Updates & The Science of Air Filtration

Damn, guy. Selling the discounted 3D-printed parts and providing free plans is really kind of you. Thank you.

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!

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!!!

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.

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.

Great job and very nice of you showing the plan how to make it - keep up a good work

Can’t wait for the rest of this series!

Can't wait for the next addition to this series and seing the other versions in use

Impressive dedication on your testing rigs. Thank you, truly. That's a public service I know took you some time, effort, and money.

This is awesome! Thank you for making this video. Definitely going to build a few of these for my woodshop.

Top notch information! Thanks

AMAZING VIDEO LOVE THE NEW VIDEOS

Can't wait for the next part.

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.

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

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

Absolutely Amazing~!!

Awesome to see you doubling down on the content that worked for you! Just getting started with taking YouTube 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!

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. https://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.