Modular 40mm NATO / RD40 canister adapter kit for Dirt Devil F2 HEPA filter

thingiverse

For testing purposes only. Use at your own risk. Wanted to make a better adapter than my previous one. Made it in pieces so that it would be easier to customize and print. It comes in four pieces: 40mm lid.stl - the top part with the rd40 thread, requiring support filter.adapter.stl - interfaces with the Dirt Devil F2 filter, needing supports canister.stl - threaded cylinder to enclose the F2 filter, no support required bottom.stl - bottom piece that threads onto the cylinder, with a hole for air intake, no support needed You will need to make your own gasket. I had rubber sheets on hand and it was easy to cut one out from a trace of the filter flange. The material is roughly equivalent to bicycle inner tube material. Initial fit and seal seem very good. My understanding is there are different flange heights depending on which brand F2 filter you have. I am currently using 3M Filtrete branded from Amazon. The threads attaching the pieces together should also be sealed to ensure that it is airtight. I am considering using caulk, teflon tape, hot glue, or silicone tape. V2 is my first working version. V3: Changed thread location on the filter adapter part. It's more stable now, but will require supports to print. Use shorter V3 canister file for a more compact unit. 2020.06.25: Just got "Green Label" brand filters from Amazon (4 for $12). They are noticeably inferior in quality compared to 3M (less pleat density 56 vs 40) and they fit tightly on the adapter without any gasket. You could probably apply a thin layer of silicone caulk on the filter, which will be enough. 2020.06.26: Uploaded V3 canister STL. 2020.07.06: Added bot.plug.stl, it's a press-on cap for the intake hole at the bottom. I messed around with sealing large threads using teflon tape and silicone, but think the easiest way was to simply wrap the entire canister with transparent weatherseal tape that I already had from Home Depot. This guarantees the entire thing is airtight.