Flex Filament Direct Drive Extruder (Max Micron and other Prusa i3's )

** note- Updated ExtruderV4_1 uploaded Feb 9 2017- there are some minor changes that can improve the performance, but also note the tolerances in the filament path are MUCH tighter so make sure your printer is building very accurately**

Seen a bunch of extruder mods for flex Filament, some probably better. But I wanted to design my own and make it a exact swap out for my stock one. Honestly it's almost the same basic design with just a few tweaks to get flex filament to feed better and not ha