University of Michigan Medicine published an instructional video on this in 2011[4] and there are many online discussions and DIY blog posts predating 2020[5]
Both those links are about 1-filter designs though. This is a five filter design which performs better than the sum of its parts. Couldn’t find any sources on that existing earlier, should be added to the article if so
at work I hang them fan blowing down under the top tier of the pallet racking which has about a half pallet width of extra space that would otherwise be wasted. The spaces below are low enough to be feasible to use as shelving but the top one made a great out of the way filter location. Another one is attached to the outside of the mezzanine railing blowing sideways away from the mez.
Is your workshop tall enough to hang one overhead or on a wall? The fan doesn’t have to blow upwards judging by how mine always have absolutely loaded filters on all sides when I replace them.
No, I unfortunately have low ceilings or else I would definitely have hung it.
I also have it blowing into the box and expelling through the filters. I could have gone the other way but since it’s floor standing, I can use it as a huge vacuum basically. I can keep it beside where I’m sanding something and it sucks up a huge amount of the dust.
Pushing into the box also avoids the high velocity airflow that kicks up dust (though you could argue that kicking up dust makes it available for the filter to catch later).
Indeed.
Both those links are about 1-filter designs though. This is a five filter design which performs better than the sum of its parts. Couldn’t find any sources on that existing earlier, should be added to the article if so
Edit: found an imgur from 2018. https://imgur.com/gallery/hepa-filter-companion-cube-box-fan-jtECP9C
Found a triangle from 2012 https://marshallhansendesign.com/2012/01/02/studio-operations/
Unfortunately both those sources are not sufficient for Wikipedia
I have one of these for my woodworking shop. It takes up substantial space in my small shop, but massively improves the air quality.
at work I hang them fan blowing down under the top tier of the pallet racking which has about a half pallet width of extra space that would otherwise be wasted. The spaces below are low enough to be feasible to use as shelving but the top one made a great out of the way filter location. Another one is attached to the outside of the mezzanine railing blowing sideways away from the mez.
Is your workshop tall enough to hang one overhead or on a wall? The fan doesn’t have to blow upwards judging by how mine always have absolutely loaded filters on all sides when I replace them.
No, I unfortunately have low ceilings or else I would definitely have hung it.
I also have it blowing into the box and expelling through the filters. I could have gone the other way but since it’s floor standing, I can use it as a huge vacuum basically. I can keep it beside where I’m sanding something and it sucks up a huge amount of the dust.
Pushing into the box also avoids the high velocity airflow that kicks up dust (though you could argue that kicking up dust makes it available for the filter to catch later).
I built it based on this guy’s testing: https://youtu.be/FDroqRfWiWE