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Anonymous10/11/25, 08:09No.2950162
I recently moved to an apartment that's second floor street side, and the amount of dust I get is insane. I have to vacuum every day, sometimes twice a day.
I heard about Corsi Rosenthal boxes as DIY air purifiers and figured I'd give them a try since I think a conventional air purifier with my budget wouldn't do much, but I've encountered two roadblocks.
1. Box fans seem to be virtually non-existent in Europe. I've only found a 30cm desk one, though the guides online seem to recommend at least 50cm wide ones. Instead we got those circular ones, though I guess I could use cardboard to make a square frame for it.
2. Merv 13 filters which were recommended seem to also be an US thing, getting them in Europe costs me twice as much. I've read that HEPA filters don't work as well because of airflow pressure stuff that I'm too dumb to understand, so I don't know if there's an european Merv 13 equivalent.
So my question is, are there any europeans here who made CR boxes? And if so, what did you use, and did you manage to stay in a $200 budget?
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Anon10/11/25, 13:24No.2950189
>Corsi Rosenthal boxes
stop calling them that
>though I guess I could use cardboard to make a square frame for it.
makes sense. box fan blades don't scribe a square, they are also a circle cut into a square frame
>I've read that HEPA filters don't work as well
iirc hepa is not a single filter, it describes a range of filters which exceed some particle size filtration.
the smaller the filter grid, the smaller particles it will catch, however it will also clog much faster and require a more powerful fan. and presumably the cost will be affected.
i would suggest you start with as large a filter as you think will help and if it doesn't, replace with a smaller one.
i would suggest bang for buck fan wise look at 10 to 12 inch duct fans, flat pancake style which work on centrifugal principle will overcome a lot of pressure issues with high filtration, at the cost of noise.
suggest you look at the flow/pressure curve of the fan and the impedance of the filter and work out from there how many room air volume changes per hour you will achieve. shitting together some crap from a box shed is easy, doing it properly and efficiently takes some amount of effort.
remember the curve is important. a 2000cmf desk fan will achieve nowhere near that figure once you add filter impedance. you need to know the fan curve.
you can always make your box much larger if you can afford more filter area.
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Anon10/11/25, 13:58No.2950192
Not OP but would a screen cover work for keeping out some of the dust?
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Anon10/11/25, 14:27No.2950195
> Box fans seem to be virtually non-existent in Europe
Good. In the depicted orientation, the bearings on the fan can destroy themselves quickly—they weren’t designed for that orientation.
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Anon10/11/25, 20:20No.2950228
My old window intake compatible design
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Anon10/11/25, 21:39No.2950262
Merv 13 is something like an f7 or ISO EPM1 filter in europe.
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Anon10/12/25, 10:05No.2950359
OP here. Searching around I came across this sort of PC case where you can put two ikea filters on the side and blow the air with 4 fans. (The Nukit Tempest Euro)
https://cybernightmarket.com/products/the-nukit-tempest-euro-pc-fan-air-purifier-kit
Price wise, $150 plus 4 fans would put me right at the limit of my budget, and I think it would filter less air than the classic 20 inch CR box, but getting ikea filters is cheaper and easier for me long term.
Opinions?
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Anon10/13/25, 12:52No.2950533
These are great
Though, I do a triple layer, Merv 5, 8, and 13
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Anon10/15/25, 15:22No.2950965
brake dust is likely kevlar and metal. conductive materials, look into ionic purifiers maybe install a foot switch for easier maintance.hepa filters rip almost immediately, they are a clean room thing, for use after the air has been heavily filter.
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Anon10/15/25, 15:37No.2950966
Checked diy and found a thread with a similar situation here (i'm in SEA). Looking for something that will deal with VOCs because nigs are chain vaping a sauna around my apartment. Also can I say vaping is completely retarded here with kids putting ketamine and anasthetics in their chink vapes.
Apparently carbon soaks fast from the 3d printing guys so thats a no go. If I can find cheap hepa filters here that'd be the best solution and replace them every couple months but they're non existent here. So I've been looking at these long term filters like the Daikin Streamer which I think uses electrostatic tech? Why do japanese filter brands last 10 years while others need frequent rechanging?
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Anon10/15/25, 15:49No.2950967
Also OP and /diy/ could take a look at this made from a table fan. Is it even comparable to a fan attached to a MERV filter? But maybe if you're just looking at large particle filtration this might work for you.
https://witonosfreestyle.wordpress.com/2015/09/26/diy-air-purifier-in-less-than-15min/
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Anon10/15/25, 20:21No.2951033
how about making the filters yourself?
get some fabric and sew a long sock that you attach to your fan.
If you need the sock to hold it's shape you use wire or some kind of basket (wire trash can, milk crate with holes, etc)
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Anon10/16/25, 00:16No.2951061
>merv
bagagwa
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Anon10/18/25, 07:35No.2951464
i can't imagine these perform worse than something like pic related. i have one just like this and i've not changed the filter in like 6 years, but it does have a pre-filter that i take out and rinse off. it's mostly for white noise to keep the tinnitus away.
the problem is that a box fan with HVAC filters taped to it looks like shit. i can have pic related in my room and not look like a broke nigga
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Anon10/18/25, 09:20No.2951475
If you feel the need to vacuum the dust particles are big. That shit in your pic is for small dust.
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Anon10/18/25, 21:39No.2951608
Just buy an AirFanta 3Pro. Widely available in Europe, uses much more efficient HEPA filters, uses silent PC fans, and it is cheaper.
