Vectric Customer

Ok, this is COOL. It's called a Rattleback and it is one of the best things I have carved yet using Aspire. Why? Because I could download the STL, put a chunk of Walnut in my machine and an hour later had this Physics-defying toy. You heard me: it ONLY spins to the LEFT. If you try to spin it to the right, it does ~2 turns, wobbles and REVERSES course ... North of the Equator that is.

If you want the full-on physics explanation, try this:

If you want to make one of your own, simply search for Rattleback STL and go to town. As I understand it, it is an Australian toy...wow!

wood_fly wrote: ↑

Tue Jun 01, 2021 8:07 pm

Physics-defying toy…

If you want the full-on physics explanation, try this….

Not physics defying but human intuition defying. If it was physics defying there wouldn’t be a “full-on physics explanation” of why it works.

In 1985 Fine Woodworking magazine featured making one: https://www.sfu.ca/phys/demos/demoind ... celt.html

My grade 8 science teacher had one back 40-odd years ago and it was called a “celt” then.

So I packed it in my bag and took it on a recent flight to Rio ... any guesses on the effect on spin?

That was fun to watch the passengers get confounded in the back <g>