Quick Change Filament Filter

thingiverse

This is a fully parametric quick-change filament filter designed to prevent dust on the filament from entering your extruder and clogging it up. It was inspired by the CreativeTools Universal Filter, but trying to force a sponge into that closed filter just didn't make sense to me. So instead I used OpenSCAD to design a two-piece threaded filter that screws together easily, and put slits on the side so it could be slipped onto and off of the filament without disconnecting from the extruder. Then I added tabs on the side so it could still be unscrewed even if it got a little lubricating oil on the side. After creating this, I found Kezat's filter which followed the same philosophy, so I listed this as a remix since he had the idea first. I added 1.75mm and 3mm versions, because changing only one variable makes sense. I only tested the 1.75mm version, but if there are any problems with the 3mm version, let me know in the comments. It's essential to choose a soft sponge for inside so it tightly wraps around the filament. You should then add a little lubricating oil to the sponge before inserting it, to help it flow smoothly and grip the filament tightly. CreativeTools recommended mineral oil, but I ran out of that and found grapeseed oil worked fine at PLA-printing temperatures. If you experiment with alternates, intentionally stay above the oil's smoke point. After the first print, very little oil passes through into the print. After assembling it, make sure it slides freely up and down on the filament, but with an obvious grip of the sponge around the filament. Note: The OpenSCAD file uses my threading library for the threaded rod feature that forms the basic structure of this. It's just a hollowed out threaded rod with a slit and tabs. http://www.thingiverse.com/thing:1686322 Update 2016-07-28: My wife pointed out that the top and bottom of this were not obvious during filament changes. Therefore version 2 is now labeled "IN" and "OUT" on the two sides. It makes a difference if you turn it around and push the dirt you filtered back out the input side, so this is an important distinction. Also, change your sponges once in a while if you want to see evidence that these actually work. Update 2017-12-24: Something changed in Cura that made the connection of the external threads to the base print out much thinner than before, so version 3 has this thickened slightly. Printer: HICTOP 3DP-11 Rafts: No Supports: No Resolution: 0.5 x/y, 0.2 z, 1.5 perimeter, 1.0 top/bottom Infill: 50% Notes: Infill doesn't matter much since this object is mostly perimeter anyway. But I recommend at least two layers for the perimeter so that the threads don't snap off if you tighten it down too tightly. I used three layers and 50% and found it very sturdy.