[#1 updated the design slightly with a tapered ptfe tube hole to allow it to slide in better]
[#2 updated it a little more to make it smoother to accept filament]

An easy print to enable you to attach a wide filament spool to the side of the machine.  I've also added a hole for some 4mm OD PTFE tube to make it really easy to load it.  It's been designed with a slight angle which means the spool should always slide toward the machine. 

I used some M3x20mm screws to attach it, using the original filament spool holder fixings holes.

I've done my test print in PLA 30% infill, 0.2 height but with 5 walls / 5 top / 5 bottom, so it's near enough solid.  Seems strong enough but time will tell.