The other day I ordered a new 1kg spool of PLA for my Ultimaker 2 but didn’t think of the spool being bigger in comparison to a standard 0,75 kg spool. I had printed / assembled some bearing supported spool holder + filament guide to fix the prominent Ultimaker 2 filament guiding issues just to realize that the new spool won’t fit on the holder.
I decided to move the spool into the space above my Ultimaker and make some quick and dirty hacks to introduce a well working setup without investing another 1 or 2 days. This would give me the feeling being smart not throwing additional time on something that should have worked out of the box (I’ll write about my experience with the standard filament guide in an separate article).
So first I removed some of the packaging that I usually store in that space and drilled two 8 mm holes about 5mm deep into the sides of the locker. I then cut a 6 mm threaded rod to exactly the width of the locker plus the 2x5mm. The rod flexes a lot so you stick it into one of the holes, bend it a bit and move it into the second one.
This ends up in a situation where the filament is aggressively guided around the sharp edges of the shelf. In terms of friction not any better than the original Ultimaker design.
Since my spool holder is not needed at the moment I though I could used it as an over dimensioned filament guide. This gives me again the good feeling of not having wasted any time on the initial improvements. I took a piece of scrap MDF board and screwed two spacer strips on the backside after I cut the openings for the holder into the board using my drill & jig saw. This is of course not perfect yet as the filamnet still touches the shelf but the remaining friction will not cause filament to break.
However there was still one other issue: The spool was not centered on the rod (have a look at the first picture) and the force necessary to pull the filament off the spool was too high. As a solution I cut a 10 cm piece of 4×4 cm beech tree, drilled a 10mm hole into it and added two 16mm holes for the bearings. The bearing radius is 8,5mm so they sit tight and will to fall off the wood any time soon.
The spool is rotating perfectly now – way better then before.
I haven’t extensively tested this with ultra long print outs (24 hours and above) but 2 hour prints caused zero issues so far. I started to like the idea to generally move filament into that space above the printer which gives me additional comfort turning the printer inside the locker for filament change / maintenance.