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
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.
collapsed inline media
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.