Not satisfied with the specs of off-the-shelf brushless DC motors? Looking to up the difficulty level on your next quadcopter build? Or perhaps you just define “DIY” as rigorously as possible? If any of those are true, you might want to check out this hand-wound, 3D-printed brushless DC motor.
There might be another reason behind [Christoph Laimer]’s build — moar power! The BLDC he created looks more like a ceiling fan motor than something you’d see on a quad, and clocks in at a respectable 600 watts and 80% efficiency. The motor uses 3D-printed parts for the rotor, stator, and stator mount. The rotor is printed from PETG, while the stator uses magnetic PLA to increase the flux and handle the heat better. Neodymium magnets are slipped into slots in the rotor in a Halbach arrangement to increase the magnetic field inside the rotor. Balancing the weights and strengths of the magnets and winding the stator seem like tedious jobs, but [Cristoph] provides detailed instructions that should see you through these processes. The videos below shows an impressive test of the motor. Even limited to 8,000 rpm from its theoretical 15k max, it’s a bit scary.
Looking for a more educational that practical BLDC build? Try one cobbled from PVC pipes, or even this see-through scrap-bin BLDC.
Continue reading “Powerful, Professional Brushless Motor From 3D-Printed Parts”



A single motor runs the entire drive chain using linkages that will look familiar to anyone who has taken an elliptical trainer apart, and there’s not a computer or sensor on board. The PER keeps its balance by what the team calls “reactive resilience”: torsion springs between the drive sprocket and cranks automatically modulate the power to both the landing leg and the swing leg to confer stability during a run. The video below shows this well if you single-frame it starting at 2:03; note the variable angles of the crank arms as the robot works through its stride.
[VijeMiller] has aluminum extrusion tastes on a cardboard budget, but don’t let that put you off this clever build. The idea is pretty simple: a two-axis plotter that moves a rotary-action business end to any point within a V-shaped work envelope. The Arduino in the base talks to a smartphone app that lets you point to exactly the spot in need of attention on what for most of us would be an incredibly optimistic photorealistic map of the dorsal aspect of the body (mildly NSFW photo in the link above dips below the posterior border). Point, click, sweet relief.

[Nick] is designing a new kind of RepRap, 