MicroDrive Extruder

Having spare clone parts from BMG Mini dual drive, I decided to design a smallest direct drive extruder I was able to.

The extruder accomodates an e3d V6 hotend in the direct drive mode, allows for a pass-through 4 mm (external) PTFE from the dual drive gears for maximum constraint on the filament path.
The feed can be done with a use of another PTFE - the housing accomodates a snap-in bowden-style holder (it was necessairy for one of my printers - I only have space to feed it from the table-level, hence ptfe feed to direct drive)

You wil need a set of original gears from BMG mini dual drive, or a set of clones (should work with the links below):

https://www.aliexpress.com/item/4000354822120.html
https://www.aliexpress.com/item/4000021186440.html


As per BOM:
1x 33 mm M3 screw (30 mm thread)
2x 38 mm M3 screw (35 mm thread)
1x 43 mm M3 screw (40 mm thread)
1x 15 mm M3 screw (12 mm thread)
2x M3 hex nut
1x snap-in ptfe collar holder
appropriate PTFE tubing
1x