DC Hobby Motor (130 size, FA-130 / FC-130 etc) mount for interlocking bricks (lego-compatible)

thingiverse

Mount a 130-size motor similar to the FA-130 or FC-130, or opt for one of the numerous knockoff versions. These direct DC motors are widely used in hobbies and feature a flattened cylindrical profile, as seen in the provided image. Don't expect a perfect fit on top studs and bottom holes without adjusting print settings. Some post-printing finishing is necessary to achieve optimal results. Use a 4.8mm drill bit or a 3/16" drill bit (approximately 4.76mm) for refining through-holes if you can't find a 4.8mm. This part pairs well with other designs, including "plus axle" adapters for 2mm axles. Check out the Related Models section for more information. Using this motor in models effectively is quite challenging due to its high speed and low torque characteristics. These motors typically operate at 9k-12k rpm unloaded, 4k-5k rpm loaded, and produce 10-20 g*cm of torque. They also lack stall protection and tend to overheat when stalled. You'll need to create a Lego-compatible gearbox with a large downshift ratio like 10:1 to achieve sensible torque for most applications. However, this approach comes with its own set of limitations, as Lego-compatible gears are often huge and clunky, making it difficult to find suitable combinations for gearbox use. For motor protection, I've experimented with various approaches, including slip drive belts and simple friction clutches. While these methods show promise, they're not yet optimal for delivering satisfying startup torque while avoiding slipping during normal operation. A driver IC would be the ideal solution, but using a gear down approach and placing the slip mechanism on the geared-down side may yield better results. In the end, I opted to switch to ["TT" style gearmotors](https://www.adafruit.com/product/3777) and designed a separate adapter for my project.