Vertical support for -Heavy duty printable filament spool-

Yet another spool holder :P

I'm using the mini one http://www.thingiverse.com/thing:11898 when making short demos with the Huxley, but I needed a big one when in "production mode" at the FabLab.
Thus I made this vertical support (inspired by a bow holder) which is compatible with the hub of the "Heavy Duty" kind of spool :)