No Clunk Gears for Gravity Spool Holder - MMU2S

prusaprinters

Like many I found the Gravity Spool holder by Michal Fanta to be a superb design, with one annoying feature for me.  The ‘clunk’ as it hits the top was annoying especially for long prints which go at night.  Highrise Workshop came up with a design to combat this and although I like the idea it introduced further potential issues and variables for me.  Having to get the grip on the spool just right to be tight enough for the gears to work yet allow slip at the top.  Multiply this by 5 spools and with all the struggles of the MMU2S I wanted to find a different solution, one I think builds on the design but is more reliable.  I therefore take the stopper from the NoClunk design and use a two part/dual material slip gear.  I have tried PLA and PETG for the centre, I'm using TPU for the outer gears.  There is a potential for variance in my design, so I include step files in case you need to tweak the outer gears centre diameter.  It needs to be tight enough to grip sufficiently to turn with the spool and ride up yet then slip once it hits the stoppers.  I found 18.2mm to be ideal which is the size in the STL's.  Printed on my MK3S.The centres I printed at 0.2mm layers, 15% infil.  The outer gears 0.2mm and 0% infil.Hopefully my design works for you but if not tweak it.  The benefit of this approach is once you have the right fit then you can print a set and have a consistent result (hopefully).Video of them in action, it’s not very exciting…..