Printrbot Play Adjustable Width Spool Holder

**UPDATE 4/28/16:
I have designed a filament guide that can be used in conjunction with this spool holder to help prevent the spool from being pulled off if the filament binds. The filament guide can be found here: http://www.thingiverse.com/thing:1526925.

**UPDATE 4/24/16:
WARNING: The filament may have a tendency to bind on your spool, and the extruder could pull the spool off of this spool holder. I ran a long unattended print last night, and somewhere around the 2 hour mark, it appears that the filament on the spool got bound up a bit, and the spool was pulled off of the holder. I will be designing a fix for this in the near future, but in the meantime, just be aware of this issue. (credit to jdalemarrowstone for pointing out this issue).

**UPDATE 4/13/16:
I uploaded the files for the modified version that uses 608 skateboard bearings. Just choose the appropriate files for the bearings you want to use. However, i should note that I have not tried printing the 608