I'm currently upgrading my Ultimaker II with a "Low friction UM2 spoolholder" the YouMagine user IRobertI.
As I print a lot, I use huge and heavy Colorfabb 2.2Kg spools.
So when a spool is fresh and heavy, there is a lot of friction involved that the extruder needs to overcome.
My hope is to reduce this friction a great deal with this simple upgrade.
- Print "608 mount" ith lots of infill, a large nozzle and thick layers. It needs to be strong.
- M8x140 is plenty of length. It should have a hex head, so you only need 2 M8 nuts
- You can use counter nuts (4 in total), so the nuts stay in place even with lots of vibration over a long time period
- Use a bolt that has threads all the way (no smooth shaf and only threads at the tip)
- Clean up the inside of "608 Core2 90mm" and "core 1", so a 608 bearing can be inserted into the far end
- check the order of assembly:
- insert M8x100 hex headed bolt into "608 mount
- add M8 nut and 608 (skateboard) bearing, so "core 1" has a small air-gap wi "608 mount"
- add "core 1"
- add spacer
- add another 608 bearing and M8 nut (don't overrighten)
- add "608 Core2 90mm"
- add final "608 nut"