Filament Spool Holder for 4040 Profile 8

You can use this spoolholder on a HypeCube 4040, so build with a 4040 Profile 8 frame

The mount facilitates a M8 100mm bolt with wing nut and the Spool Holder from

http://www.thingiverse.com/thing:2084725

I've designed the holder to allow for 2 of these to be placed on one rib.
And it is symetrical too...

The design frame inside distance is 450mm.
I've assumed a 1kg/D20cm filament spool.