I first thought of the idea to make a Yin-Yang fidget spinner when I saw a decent rendition of one, though not exceptional by any standards I decided to make one. I call it the SpinTeck Zen. However, I do admit that mine is probably just as bad (or worse!) than the first one I saw, but I like it, and I hope you guys do too.
Step 1: Making Yin and Yang
I made the 3D model in AutoCad software sized to tightly fit a 22m bearing. The total diameter of both Yin and Yang together is 76 mm (Roughly 3 in.) I would recommend using a degreased skate bearing for the center, and metal weights for the outside.
Step 2: Printing the Parts
To bring Yin and Yang into the tangible and physical world, I used a Prusa 3D printer. The layer thickness does not really matter, because there are no vertical curves or complicated shapes.
If you have a dual extruder or multi-color print mode, then I would download the full Yin-Yang files, and if you don't, then it would be best to separately print each side of the spinner, and spray paint one white and one black.
*If you do not own a 3D printer, then you can get 3D printing services (like Shapeways) to print the parts for you.
Step 3: Files for Yin-Yang
Anyway, that's all I have for now. If you have questions/ ways to improve please comment, and I will do my best to fix any problems.
Step 4: Yin-Yang Version 2- Made for a Better Fit
I developed a Version 2 of my Yin-Yang Fidget Spinner after printing the first version, and seeing that the bearings were not centered where the black/white dots should have been. To solve the problem, I increased the diameter of the spinner from 76mm (Roughly 3 in.) to 100mm (Roughly 4 in.)