42.5: Non-Circular Planetary Gear Created
Mathnetism Has Succeeded..
.. in designing a planetary gear set, with non-circular planet gears, using only magnet spheres. This was an expert build, of a genius design. $300 Zen Awarded.
Here’s his demo video:
And here’s our recreation of Mathnetism’s design, to confirm form and function:
The video above is already in red/cyan, since YouTube 3D seems less consistent with it’s YT3D feature. In case YT3D is working for you, here’s the same video in side-by-side format.
We followed Mathnetism’s tutorial video (here) the best we could, but what he does on camera in ten minutes, literally took us hours to recreate.
Creating the exterior ring gear was so much harder than Mathnetism’s tutorial makes it look. Starting with a wobbly 9 sheet, and converting it into a solid rigid configuration by laying down a precise line of magnets, is insane. Don’t even attempt it if you don’t have good chain manipulation habits, because your dominant hand will need to have a continuous feed of magnets that must not attach anywhere unintended. The base structure for the ring gear, built in the first four minutes of Mathnetism’s tutorial video, literally took us 2 hours to make, and we had to use a different method. We couldn’t get past solidifying the 3rd section of the ring gear without making a terminal error; in the end we built the sections individually and connected them. It was messy.
The planetary gears are a relief to construct, compared to the ring gear. Though, again, at 8:25, is wizardry that is beyond our skill level. “Whoa what the hell is going on.” The manner in which he shifts two columns of magnets in a ring, consistently, for a loop that is decreasing in diameter with every shift, is mind-blowing. Or perhaps our fingers are fat, and we never realized it until now.
To top it all off, Mathnetism slides the sun gear in there with a little bit of jiggling, as if a brain-surgeon’s precision isn’t a big deal. A few centimeters error in this part, will probably result in unfix-able situation that wastes some time.
Once everything is together, you’re still not out of the woods. The sun gears like some configurations better than others, and certain combinations of planetary gear position/rotation will result in slippage, which will then result is a gear that breaks itself. But there do exist positions that the planetary gears can be in that will allow the gearset to continue operating indefinitely.
Mathnetism makes this using only his two hands. No cards, no tools, no 3rd hard. That’s crazy. If you are up for a challenge and have a mandala set (or specifically 1206 magnets) give this try. It was a humbling experience for us. Our skills are apparently rusty. Or Mathnetism is a freaking magnet magician. Or both.