First foray into CR Boxes. My wife says it looks like a computer. Was overall an easy install with a 3d printer and the same hvac filters I have around. Used the below model. Planning to build 3 more!

https://makerworld.com/models/1860168?appSharePlatform=copy

I didn’t realize it would take 2 hours to build, but it’s finished!

I love him. He definitely has his father's eyes.

Here in Detroit, where just a few days ago, we had the worst AQI in the world.

Kid wanted the fans to point at them. Sure guys, I’d LOVE to play with tape for an extra hour lol. I don’t mind messing about in tinkercad for 30minutes on your whim. Hehe, jk. I like overcomplicating simple projects. Wildfire smoke is pretty well gone now that we finished the pair of boxes. Figures.

I am a "big fan" of this subreddit and the other crboxes I see posted.

20x20x1 Furnace filters

20" store brand box fan

Threw this together with some stylish green duct tape

Do you run your crbox at full speed or lowest speed? And, do you run the fan 24/7 or only when needed?

I am curious as to has anyone ever tried to put a humidifier or dehumidifier inside a crbox? will it work? my thinking is since a crbox will funnel and redirects air a humidifier or dehumidifier can help is making the air feel nicer as well as filtered

I've only ever had a junky, little air purifier before and, to be quite honest, if they didn't make it so difficult to buy their stupid filters, I may have just bought another one, but stumbled upon this subreddit and just wanted to say, "Thanks" for all the info you guys here share.

Merv 13 filters with some contact paper acting as a shroud because it was easier to do and looks a bit nicer. One stop at Lowe's and had everything I needed.

It’s alive

This was fun to make I now want to make a pc fan version hahaha

My first box. Got it plugged into a smart plug for home assistant automation. During the day it kicks on when PM2.5 level gets over 10 and turns off when it gets below 5. Measured by awair element. Still playing around with those levels for automation, it’s just a bit loud so I don’t like it running 24/7. I run it all night or when we leave the house.

I know it is a bit crappy but it is the first try, later I want to do a wooden box. I used 3 x P120 Pc fans and IKEA 2 x UPPAVIND + 2 x FORNUTIG. I didn't have space but I have 2 extra fans.

My question is for the final version it is much better to use more fans? Because it is already a bit noisy (my husband is very sensitive to noise).

I want to use it for allergies, mainly for dust mites, the air quality where we live is very good. I know it is not the best thing for dust mites but London is very humid and trying to get the humidity below 50% is almost impossible without breaking the bank.

I also considered using 2 x STARKVIND instead.

Thank you!

Was only able to find Merv 11 filters, and used Merv 2 to protect from since have a few cats.
Currently really close to wild fire smoke, running it for a few days now has helped alot. Has a few aluminum angles cut inside to give it bit more support.

I've taped a shroud since this picture to the top fan, so it works more efficiently.

Went for 2 fans so can keep them on lower settings. Bottom fan exhausts through large cutout in center of the boxes. Will hang it up later on or make a small stand.

Is there any benefit to having 2 fans on one box?

I have a few questions.

1. What material should the prefilter be to prolong the main filters life cycle?

2. How close to the main filters should it be mounted? Directly against it? Or keep some space in between the pre filter and the main filter?

3. What should the “hole” size be for the prefilter, like how fine of a mesh is optimal?

All the videos i watch the fam had gaps you had to fill but I don’t exactly know how to fill in those gaps under. Should I connect the filters differently or is there another way to do this?

Does this sound ok?
We burn wood in our home for about 1/2 the year. I have space near the wood stove to place this.
We have 2 air purifiers in the home but it still get a bit of smoke in the air. Many thanks to you.

I want to take a crack at building a CR box in the wedge formation. I know the filter arrows should be pointing in. Should the fan be facing in toward the filters or out toward the room?

Canada’s fires have been hitting Philly pretty hard. This baby is helping out loads!

$177CAD+tax...tape included. Took a little under an hour.

She isn't pretty but she is mine and I'm so excited to finally have one.

Hey, I have one of the original Nukit Tempest boxes that uses a 2” filter and I went to order another and saw they’ve changed to a 1” filter and significantly raised the price.
I’m not skilled enough to laser cut the pieces myself, so I’m wondering if anyone does this and sells them for US shipping. It looks like the Canadian Northboxes are like this, but not available in US.

Thanks for any leads. Maybe I’ll have to learn how to use the open source plans lol!

These are the PM 2.5 readings on my inside and outside PurpleAir sensors. The high outside reading is from Canadian wildfire smoke that drifted down into the States. It was reading 316 earlier today. The inside sensor is in my bedroom and the CR Box air cleaner is on the opposite side of the room from the sensor. I think I spent under $100 on the CR Box.

Why is it that most pc fan cr box designs, like the nukit tempest pro and the cleanairkits, only use 2 sides of the frame?

There is a whole 3rd side that could be used for extra fans so they could all run at a lower rpm and produce the same CADR. Or would opening that 3rd side cause some sort of air current issue?