Rolling-Screw Extruder Goes Brushless

In the name of saving weight and pushing plastic, it’s nice to see continuous tweaks on 3D printer extruders from folks in their spare time. And to go where no extruder has gone before, [wayne dalton] has managed to combine the rolling screw thread extruder concept directly onto a brushless pancake motor. The result is a filament pushing mechanism weighing in at just under 90 grams. What’s more, this modification arrives a few weeks weeks after we first saw an open source version of the rolling screw thread extruder land on Thingiverse back in September.

Getting a direct-drive BLDC extruder off the ground comes with a number of geometry challenges. First, filament needs to be fed through a motor with a hollow shaft. Since this motor will be operated under closed loop control via an ODrive, the motor also requires an encoder with a hole down the middle too. [wayne dalton] patiently walks us through all the changes made over seven iterations to produce a setup that will eventually mount onto a machine and start printing. But for that last step we’ll need to check back a bit later. Finally, this progress comes with the promise of a possible open source release of the design files, so we’re pretty eager to stay tuned for future videos.

In the last few years, we’ve seen state-of-the-art extruders move away from NEMA 17 motors in favor of more compact solutions like planetary gears and even lasers to push printers faster. We’re excited to see that folks keep trying to set the bar higher.

Thanks to [ImpC] for the tip!