Summary I created this mounting system so I could change out the filament easily on the Prusa i3 MK2. This design allows the filament to unroll naturally with barely any friction. It also puts a lot less pressure on the x-motor so it doesn't have to apply so much force on the filament roll. I use this design with a 5mm all thread and my universal filament spool shown in the link below. http://www.thingiverse.com/thing:2303240 Overall, I can take the spool off a lot easier and my prints have a lot less mistakes to them. Let me know if you have any questions. I would be happy to answer them. Print Settings Printer Brand: Prusa Printer: Prusa Mk2 Rafts: No Supports: No Resolution: .15 Infill: 20 Notes: Any resolution will work.