Loose Thrust-like Bearing

thingiverse

UPDATE: I made two key modifications: I added hex shafts, enabling things to turn properly, and a small snap mechanism so balls won't fall out when closed. The snap piece is slightly oversized, but since I only need one, I didn't adjust the file. I needed a thrust bearing type component for my Lego BB-8 gyro/pendulum/hamster. Although I had purchased a small bearing, it wouldn't work, and I had some 1/4" Acetal balls lying around, so I made upper & lower races for them. It's challenging to see this in action, so I created a video of the spinning components: https://youtu.be/8dvflMZPUWg, and another one that doesn't provide much insight: https://youtu.be/s5WQSzcg234 - feel free to visit the advertisers to support my endeavors :). The intended load is on top of the balls. Loads applied to the end of the upper ring will cause it to rub against the bottom. The bottom race's inner wall is lower, and the upper race's outer wall is shorter. My thinking is that maybe the balls get pushed to the outside, and the top gets pushed toward the center. However, I'm unsure if this actually happens; perhaps a more oval cross-section would have been needed. You'll need about 19 Acetal (Delrin) 1/4" bearings. The race is slightly larger due to my printer error, but you might need to scale it slightly (very slightly). You don't want the race completely packed with bearings - 18 or 19 should be sufficient. I purchased bearings from McMaster-Carr. Print Settings: Printer: FlashForge Rafts: Yes Supports: Yes Resolution: .2mm (Standard) Infill: 20% (expecting a load) / 4 shells Notes: Both STL's are upside down, sorry. This is not intended to be useful as-is. However, it might work if you need it. The bottom race is designed for a hole in a board, but I expect most folks will want to modify the SketchUp files or integrate them into more practical housings. Indeed, the top is just a test piece; my actual part will be more complex for my requirements. My prototype had a nice small gap, but if yours rubs, you might want to adjust the files to trim some of the lips. I filed down the lip of the snap on the top one so it could snap into the bottom because it was slightly oversized. That ridge is just to prevent accidental disassembly.