Bondtech BMG Dual Drive Extruder


A dual drive extruder allows for the best grip and most accurate feeding possible.  I got this for my CR-10, but it is the perfect addition to any direct drive setup.  I reviewed this in this video:

The Bondtech BMG extruder is a lightweight, powerful dual-drive extruder capable of operating in direct drive or bowden 3D printers. The BMG features a 3:1 gear ratio, the perfect combination of speed for high flow applications and precision for tiny nozzle, high resolution parts.

Note that this extruder is sold without a motor, add one on if you need it!



Two drive wheels grip the filament from both sides, providing a strong and reliable feed into the hotend. From common materials like PLA and ABS to flexibles like PRO Series Flex or Ninjaflex, the dual-drive gears of the Bondtech BMG will deliver a consistent flow of filament in either direct drive or bowden configurations.


The BMG is designed with a door on the side which holds one of the dual-drive gears. This door is held closed with a spring-tensioned thumbscrew. This thumbscrew enables precision tensioning of the drive gears for the perfect hold on filament, as well as the ability to release the tension and easily load or unload filament. All you need to do is press away from the extruder and the spring will compress just enough to release the material, letting you freely feed it directly into the hotend.


Bowden? Direct drive? The Bondtech BMG is built for either setup with a mounting slot on the bottom for a E3D hotend or a groove mount for bowden tubes. The lightweight design of the BMG makes it perfect for direct drive configurations because it reduces toolhead weight. Having a lighter toolhead means the printer can move faster without sacrificing precision or print quality due to wobble.


  • Filament diameter supported: 1.75mm
  • Weight (without motor): 75g
  • E-step value: 415
  • Compatible stepper motor: Nema17 (5mm shaft)
  • Gearing: 3:1


  • Bondtech BMG Extruder
  • Thumbscrew tensioner
  • Interface gear (mounts on stepper shaft)
  • 3 mounting screws