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 app