Ender 3 Spool Holder Bearing

cults3d

PROBLEM: I kept getting minor extrusion problems when using spools with large inner diameters - The majority of the mass hangs under the point where the spool rests on the holder, meaning the extruder has to work harder to drag the spool round. After months of printing, my axle has now developed divots and flat spots, which is making the problem worse. SOLUTION: I designed this 100% printable fix that means the spool will be nicely centred on the spool holder, and will have a lower-friction bearing to facilitate easy spinning. I found since adding this that I no longer need a filament-guide arm, which will help to fit this into an enclosure. I've also completed 36hr prints with no jamming or sticking. INSTALLATION: Super simple. Snap on two bearing spacers, and then slide on two of the print-in-place bearing. You can add more spacers to stop the two bearings sliding too close together if you need to. They should sit snugly on the axle and spin nice and easily. Then slide the spool holder into your spool if the size matches (if the inner spool diameter is too large, you'll need to print an adaptor sleeve which should be very simple to design in Fusion or TinkerCad). Lastly, you'll notice there is now no lip on the spool holder to keep the spool on - which is why there's a slipguard version of the snap on spacer. If you need to adjust the length of the slipguard, use sidecutters to shorten it along the layer lines. BE AWARE: This requires good tolerances for the bearing part and (for me at least) that meant quite slow speeds. It took me about 8 hours to do both bearings, because I didn't want to take any chances. The snap on pieces can be done quick and dirty though. Also note that THIS WON'T WORK FOR SPOOLS WITH NARROW INNER DIAMETERS, because the bearing will actually be too big to fit(!) This isn't a problem because you shouldn't need this fix in the first place if you're using spools that have smaller inner diameters. Also-also note that this bearing obviously has way more play in it than a 'real' metal bearing. It's not a problem as long as you have two of them to keep the load nice and even, but I really wouldn't try using just one.