SummaryNot really created by me but by Josef Prusa. I only fixed and adapted it to use a particular type of hotend off eBay. Being GPLd I have no other choice than to license it the same :-) All the fixes I've done are issues reported in the Prusa3 github too https://github.com/josefprusa/Prusa3.InstructionsPrint it, attach your hotend and off you go. Idler will need a 608 bearing, shaft can be some leftover from your 8mm studding. M3 bolts with springs will press the idler against the body to press the filament against the gear drive. Hotend is like this: http://www.ebay.es/itm/2x-HotEnd-Fully-Assembled-and-Wired-FREE-Hobbed-Bolt-RepRap-3D-Printer-Hot-End-/281065376447?pt=LH_DefaultDomain_3