Adjustable Filament Holder (which may also be used as pulleys)
by idea_beans, published
The filament holder that came with my UP! Plus printer didn't quite work for me because I have got so many different filaments sourced from different suppliers, some spools are thicker with smaller holes and some spools are thinner but with bigger holes.
I searched on Thingiverse to find a new filament holder that'll suit all these different spools, but there were only 2 adjustable ones I could find. I decided to design one myself that I can print in one go without any assembling.
I've replaced the filament guide to this one I found on Thingiverse (http://www.thingiverse.com/thing:31961) because the original filament holder/guide from UP was in one piece.
Print 2x the STL file, exactly as it was uploaded.
Remove the support structure carefully to free the wheels.
For stability, use 2x BBQ skewer sticks to join the 2 sides together, as shown in the photos.
Adjust the width to suit different size of filament spools. :)