Cheap Air Filtration/Dust Mitigation

I’ve been soaking in all sorts of great advice here, I want to try and contribute something that may be new to y’all.

I read an article a while ago about an engineer who came up with a cheap way for people in China to purify the air in their homes. A box fan with a furnace filter taped to it.

I’ve been running these two for a while, I’ve probably changed the filters 4 or 5 times. This last time was the longest I’d ever gone. So long I forgot what color they were supposed to be. These are definitely helping with the dust in the garage (shop). While I think it’s best to still wear a mask, or use something that actually vents, I think these are still a benefit. Especially with how cheap you can set them up for.


*Edit, I haven’t googled this setup in while, there’s a lot of info on it now. I plan on cleaning up my configuration, but I’m still working on my garage remodel for all the big stuff I need to find a way to store.

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Yeah I don’t know. I run my stuff in my shop/garage usually with the garage door open. It’s a two car garage with an extra door and area off to the side for laundry/storage. I’m not sure how much filtration of the moveable air would actually occur with that setup. It seems you would have to direct the air flow specifically. Like, only air comes through a window with your setup on it, and then gets pulled out another window via a fan. However with a garage I’m not sure how well that could happen.

Of course these are just my thoughts. I have no intelligence to back it up.

I use a box fan behind my powder coating booth with an air filter on it. It draws the air outside a window of my garage. This way I don’t have to smell the fumes in the garage and it has worked surprisingly well.

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You can actually watch smoke get drawn up to the fans while they are running. The filters and the inside of the fans were caked with metal dust, it all picked up off the driveway with my magnetic broom. They are definitely catching some crap. They aren’t the game changing solution, but I think they’re worth it.

For me their primary use is wintertime when I have to keep the door closed, but I have run them with the door open as well. Especially when blowing out the garage.

We use a lot of these HEPA filter units at work. It does 1350/1900 CFM…The boss was going to throw this “not working” one out. He says “by the time I pay you to fix it etc…etc.” and so on…

I said, “I’ll take it…”

Long story short…It’s getting a new on/off switch and motor run capacitor next week to the tune of about $25bux…Should purr like a kitten…

Trying to decide on keeping it (space considerations!! ) or, sell it and buy a few more tools… We’ll see… New, these things go for around $1000 :wink:

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Why are you filtering the air leaving the shop? Wouldn’t that cut down on airflow

I don’t advocate killing the outdoors, just curious (is it to keep the metal dust off vehicles?)

I use a box fan and filter like Gunny to keep over spray off stuff outdoors

I’m seriously thinking on adding a small room on to the side of my shop just to run my table in and vent it outside or be collected in a metal dust collector I’ve purchased from grizzly .Whatever is left will be isolated to the small room instead of my entire shop.I have a brown coating on my metal walls and dust everywhere.

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My shop doubles for metal and wood work. Welding/grinding/etc leaves a coat of nasty dust on my racked raw materials. I’m going to set up an enclosure inside my shop, surrounding the plasma table and belt grinder and put that enclosure under negative pressure and through particulate filtering. has some (relatively) inexpensive light channel we have used at the lab (day job) to set up temporary clean rooms. Probably cheaper than an external structure.

Here is a link to their Quick Frame product:

Not as sexy as the T Slot profile most people are familiar with.

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Nice! I have a harbor freight 8in ventilator that vents outside. I have the long flexible hose on it to snake it where I need it.

The box fans hang on my ceiling and are meant to catch all the crap that ends up floating up above and settling on all my storage stuff and bikes and what not. I found little magnets across the garage with a fine coating of metal dust and it got my paranoid. Seeing as how these loaded up with dust while hanging from the ceiling, I feel like there’s a benefit. Seems like if it were t for the fans that giant coating of dust would have ended up elsewhere.

I see how it looked weird with the photos I took. Those were just the clean out photos. I’ll take one of them hanging a bit later.

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Its obvious you are collecting some of it with your method. It cant hurt that’s for sure.

The 80/20 extrusion is all the rage for off road roof racks these days. I absolutely love it. Some of the stuff I’ll be making on my table are brackets that will bolt to the 80/20. I’d be more tempted to build an enclosure out of 1x1 tubing to save money, but the 80/20 would be a sweet setup.

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This is what the idea was based on.

I figured the metal dust particles would meet the same fate as the allergens. Here’s where I run them.


This looks quite intriguing to try. Could it actually allow you to replace the HVAC in your house? I’m up for grabs when it comes to alternatives that might prove cheaper. I’m really hesitant to buy a new system as they have become absurdly expensive now and I don’t even get it. So far I have preferred to get a duct repair service inTralalgon and it has suited me quite well. They have managed to keep the HVAC running fine even after 10 years of daily usage and I will try to prolong it as much as possible.

Pareto would be pleased. Another example of 80% of the work done with 20% of the effort. I’m going to put one or two of these together, can’t get much cheaper or easier, and I think mounted at the rear of the machine they would work decently for very little investment in time or money. It’s not HEPA rated, but I can definitely see it helping the dust situation considerably.