Tiny Flex Extruder Bowden Variant

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

Other required parts:
4mm OD Bowden Tube
Drive Gear 8mm OD 13mm length: http://reprapteile.de/mechanisch/direct-drive-geraendelter-pulley-drive-gear.html
Nema 17 Motor
624 Bearing
2x M3x12
1x M3x25
1x M4x10
4x M3 Hex Nut
4x M3x16
1x Spring 7mm OD 30mm length