Flex3Drive is flexible driveshaft based extruder system with some speed in it

Flex3Drive is a complete end to end, flexible driveshaft based extruder system offering several key advantages over other systems, including:

• a lighter X carriage 
• faster print and travel speeds 
• reduced retraction distances 
• increased retract speeds 

The extruder motor is mounted remotely from the extruder itself and attached to the frame or x ends of a printer allowing the extruder to move faster with less vibrations. Flex3DriveTM is also fully compatible with Delta type machines.

Technical specifications:

• Weight: 45 grams without hot end
• Envelope: 50 x 45 x 45mm x y z
• Gear Ratio: 40:1
• Gear Type: Nylon IM (QDrive) Worm Wheel gear set
• Hobb diameter: 11 x 8,5mm
• Filament siameter: 3mm or 1,75 no extruder change required
• Tested Filaments: ABS, PLA, Nylon (various), Laywood, NinjaFlex, Laybrick, Acetal - tglasse  and more ...
• Price: £95 + Shipping

Flex3Drive homepage with much more information:

http://mutley3d.com/Flex3Drive/

Here is a RepRap forum about it: http://forums.reprap.org/read.php?1,356635

Here are some videos of Flex3Drive in action:




Here is an overview of the mechanism:




Here is real-time retraction test: