20 Inch Box Fan Air Filter – modified

thingiverse

20 Inch Box Fan Air Filter – modified still a work in progress, but actually prints very well. just check its fit for your fan. Big thanks to https://www.thingiverse.com/thing:968923 , AtomicFix This attachment for 20 inch box fan, to attach filter, is great for workshop ! I can keep it running, and it picks up stray dust as I am cutting wood (this does NOT replace a dust collector !) His style clips onto the box fan. But, my box fan does NOT have a square front corner, the edges are tapered, so his clipped style won’t hook onto my fan without assistance. So, I modified his style, cut down the sides, added a couple wings to allow better screw holding (1 / 2 inch screws are adequate, sheet metal, they don’t hit the fan blade). The bottom, I made to support the filter itself. I mounted them about 1 / 2 inch above floor level, that way they are not getting banged against ground. You can put TOP and BOTTOM into slicer, rotoate them so thy are flat (second slicer image), and then MIRROR them for the other side of fan. For the BOTTOM, there is space below it in one section, so I just added a small wing to the outer edge, so it hits the printbed, and that was enough to eliminate need for supports, for me. Hope this s of help to others