The Fidget Spinner

Inspiration

Yeah, I don't know why I built this. There were plenty of other things I could've done with my time.

How does it work?

If we look closely, all the gears on the center is encased inside. But wait. ISNT THAT IMPOSSIBLE? No, silly goose.

Everything is incased in the 3-D print because of the beauty of Fused deposition modeling (FDM). There are two kinds of 3D printers. Those with dual extruders that use support material and then normal material, and those that use a single extruder and simply use the normal material as structural support with a lower infill in order to create that support. Ones with dual extruders usually have dissolvable support, which means you can encase materials inside of each other.

Process

Started out with a simple CAD drawing. This was one of the first things I ever did, so it's p bad. If I had to do this again, I'd probably make the handle a little bigger.
First, I tried just using the Ultimaker 2, which only has the single extruder.
This is what the Gear looks like if you don't use dual extruder printers with dissolvable support. The webbed support material makes everything look really gross.
This baby is called the Stratus. It's beautiful. Simply print something on it, drop that into acetone, and watch the support material dissolve away. Then you have something that is impossible incased.

Conclusion

When it was all done, it worked like a charm. The code on the arduino is fairly simple (it was like 50 lines of code), but basically we just used fading and then I used a boolean variable that constantly switched between fading the addressable LED strip and fading the non-addressable LED strip. If I went back, I'd probably just add more sequences to the LED strip, add a bypass capacitor to the LEDs, and clean up the board on the back of the image.