My latest Reuleaux top -- and a very accurate one at that!
Worried that it might not hold together well given all the outward-pointing connections. But I can twirl it fast enough for a 40 s spin time with nothing even starting to unseat!
Balance is perfect when all parts are fully seated, but most spins suffer from a slight flexure wobble.
Took this LEGO
Reuleaux triangle solution from the video below by Akiyuki -- IMO, the greatest designer and builder of working LEGO machines on the planet. (But pretty sure not
of this planet. Just watch some of his videos. The guy's gotta be an alien from an advanced LEGO-building civilization.)
https://youtu.be/hC0QjGbMUHIAs the video clearly shows, the Reuleaux triangle turns out to be a very special mechanical element.
My own Reuleaux top from 2015 (right) used a completely different construction method. Not as good a geometric approximation as Akiyuki's Reuleaux, but in the ballpark and
much sturdier.
This one stays up ~15 s by hand and ~20 s with a ribbon-pull starter. The triangular rotor makes for some pretty cool video effects at speed...
https://www.youtube.com/watch?v=2a6UvZjsyboSome wild effects in still photos as well...
And the top has 2 more distinct personas — one when viewed directly, and the other under a variable-speed strobe.