Tiny Flex Extruder NEMA14 Variant

This is a very simple Direct-Drive Extruder for 1.75mm Filament optimized for Flexible Filaments and easy Filament change.

This is the NEMA14 version. For the NEMA17 Version see http://www.thingiverse.com/thing:615465

Other required parts:
Merlin Hotend: http://reprap.org/wiki/Merlin_Hotend
Drive Gear 8mm OD 13mm length: http://reprapteile.de/mechanisch/direct-drive-geraendelter-pulley-drive-gear.html
Nema 14 Motor
624 Bearing
2x M3x12
1x M3x25
1x M4x10
1x Spring 7mm OD 30mm length