My Hobbyking Fabrikator prints just nice but there are times when the build volume is just not big enough. So why not use the capabilitys of the MPCNC for that? I used the MK8 Extruder and mount from Ryan and designed a compact spool holder that uses leftover parts I had from the CNC build. In my case those are two M8 metric screws with a length of 70mm, a nut and two 608 bearings. Combined it looked like this:
The clamp for 25mm tubes is fastened with four M3 *16 and nylock nuts. It can be rotated to aim at the printhead. For now it is available for center holes of 53mm and a width of 53 mm spools.
It can be downloaded here: http://www.thingiverse.com/thing:2002909