I recently stayed in an apartment that didnt have central air so I created a corsi-rosenthal box since the smoke from the Canadian wildfires were so bad.
After 30 days of continuous use, with very minimal periods of it being turned off, this is what the filters look like!
It’s disgusting yet also so satisfying to see the filters get darker from debris, dust, and dirt.
Edit: typos
Post a new one for comparison.
You can eference the outer edges for a satisfying before/after.
I’m viewing this post with the Thunder app and I only see one photo: a box with a fan on top. I see no filter. Is there supposed to be a second photo?
The box is the filter
What you see are 4 hepa filter plates taped together into a box, with a fan on top. The fan blows air upwards, thus creating a low pressure environment inside the box, which sucks the air through the filters - which are originally starch white.
Yep and if you want to get really fancy, ya can put the box on stilts and put a 5th filter on the bottom!
Ok. I’ve been looking into this a lil and there are better options than a cr box.
Housefresh has been looking into this and they recommend the nukit tempest or luggable XL or another one - think it was a Canadian brand - as the cheapest total costs over time and lowest sound and most efficient purification. All of those use regular HVAC filters which cuts down on operating cost and are quite big which cuts down electricity and sound.
So recommend getting one of those for long term use, if you have the space for it.
There’s also an open source tempest that you can use a CNC for and customize to your liking with a script. https://github.com/opennukit/Nukit-Open-Air-Purifier/tree/main/Nukit Open Air Purifier-W(all) v1.0
I have an unfinished project to make a nukit with a power knob.
I got a cardboard proof of concept working but need to make my mark 1 out of plywood or something else.
Duct tape an electrical knob device to the front and call it a day?
My loft is so freaking hot I’m sweltering. Could something like this keep my loft cooler, the window unit is struggling to cool it off until late at night
No. This actually will heat up your apartment by a measurable amount. This is purely an air quality type thing.
*measurable if you have some damn good instruments.
It will put off about as much heat as a single incandescent light bulb
Fair, and I would say < an incandescent bulb. Cause I’m damn near 40 and remember getting a good MiB experience touching one.
We did one with just one filter on the intake side. Kinda like this one better. But it takes up more room than mine. I’ll have to do some experimenting.
Corsi-rosenthal box is stupid efficient.
I’ve put an air filter in the bedroom next to the bed. Makes nice white noise too. I also have one next to the cat’s litter box. I’m thinking of putting one in the bathroom because the toilet paper makes an insane amount of lint that builds up everywhere.
I’m just amazed it apparently took two people to think of taping 4 air filters together with a fan on top.
Curious why it’s not 5 filters with some little toilet paper tubes or something for legs. Was it found that the fifth filter is diminishing returns?
Sounds like an argument that would take at least two meetings and a dozen emails if this were done by a company lol.
They may not have been the ones who first thought of it, but the first people to publish research that shows that taping 4 air filters together with a fan works decently compared to other, non-DIY filters (where “worked decently” means does a good enough job that it’s worth doing if you want a filter but can’t/won’t buy or build a more complex filtering system, even if it isn’t as good as “proper” filtering systems)
(Tangent: I’m reminded of the “Cox-Zucker machine”, a random maths thing that Cox and Zucker made together because when Cox and Zucker met at university, they realised that their names, when combined in the traditional, alphabetical order, sounded “delightfully obscene”. )
OP likes it dirty!
I built one back when I lived in California during fire season, and then again during the pandemic. They do such a nice job making the air less gross.
I think that’s about what mine looked like after 3 or 4 weeks too…
Can you put a bag of ice in this for simple ac?
You would have to go out and buy ice, if you use your own fridge to make the ice you will have a net negative energy also just buy a cheap AC, it would save so, so much energy.
Oh, leaving the house? Yeah sorry i don’t put pants on anymore. Good call.
Just get the ice delivered from the local grocery store.
Oh, that’s an interesting idea, not too much different from a swamp cooler actually so ya I think it would work.
My question is, where would be the optimal spot for the ice/icepacks:
- Inside, at the bottom
- Inside, suspended in the middle
- Inside, at the top near the fan
Hey, I have that same rug
It really ties the room together
Yeah, well, you know, that’s just, like, your opinion, man.
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I got it from my parents after they didn’t want it anymore, but I think they got it from IKEA
You’re not a true lemmy unless you own The Rug
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I have the same box fan
i have the same duct tape
Will all of you get out of my house?!?!
Nope, the air is good here. Have any beer?
I saw a couple left in the fridge. Will you grab more chips while you’re up, please?
Link? Used to have one like that but now I can’t find another one
These are great, but if you’re looking for something slightly less bulky, there’s a dude selling kits online using pc fans. I’ve got two and they’re pretty much a CR box in its final form. Kits come with laser cut panels, fans, grates, etc. only need to supply two filters. Way quieter than a box fan. They’re a bit pricey but worth since they can pretty much be placed anywhere.
google clean air kits.
For that money, you can buy actual air filtration units. The box fan may be noisy, but something that big is going to have massive surface area and provide a lot of filtration.
Can you talk about how you made this
UC Davis has a video on how to build one.
It’s literally what you see in the picture. Just household furnace filters taped into a box with a fan. You can pick your level of filtration with the type of filters you buy.
Does the fan suck or blow, and why? I seem to recall that the motor will burn out if you face it the wrong way.
It is setup to pull in air through the filters into the box and push it up through the top.
In that pic it’s blowing up, sucking intake through the filters and blowing filtered air into the room.
Looks like it’s sucking air through the filters.
I would imagine it blows upwards, so it sucks in air through the filters and blows clean air up.
Replacing those has got to be a pain with the amount of duct tape you used. And why is there tape on the bottom?
I used the box from the box fan to create a bottom to make it a bit more sturdy for moving around and ensure more air flows through the filters instead of slipping in under the filters.
It also helped making the CR Box easier. I used it as a mount point for each filter.
I duct taped the filter to the bottom piece creating a sort of hinge that let the filter lay flat outward.
I then would prop up two filters creating a corner and tape them on the inside and outside.
Then I’d do the same with the two remaining filters. Then finally tape the final two corners.
The next step i do is optional, but it made taping the fan on top easier. I created a fan shield, which is like the bottom but a big hole in the middle. Tape that on top.
Finally, place the fan on top tape it and try to seal any gaps.
You can just cut the tape at the top along the fan, than peel the left over tape off the fan and start again. The tape on the bottom is for either a 5th filter or just a peice of cardboard across the bottom for stability.
You just cut the tape off. They last a pretty long time. I’ve got one going for two years intermittently here. If it looks too rough, you can take it out side and use a vacuum or air compressor to remove a lot of the surface dust.
Tape on the bottom is for the bottom panel. Usually it’s just a cardboard sheet.
I totally did not realize how much real science was behind these things. I mean this design is so simple and obvious, it seems like something I would throw together because it just looks like it “should” work. And according to the research I just read they are very efficient and effective. Super cool!!!
I think the science comes in showing that it does actually work. Like, this is so simple of an idea that I would be skeptical of if it would work if I had had the idea by myself. I’m glad that I live in a world where, if I had thought of this and wondered “is this a good idea, or am I just being dumb for thinking something so simple could work?”, I am able to go online and find information and guides on this and other diy filters
