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[ortwin]

Spinning and a bit dangerous?
This is not Ms. Skimpy in chains that Jeremy is going to make a video of, but it another video from the same German university where we saw that container with oil and water spinning.
https://videoportal.uni-freiburg.de/video/A-617-stabilisation-einer-fahrradkette/0e7e994543c17df03469e9d553ae4f8c

[ta0]

Yep, that looks like a somewhat dangerous demonstration to do in class nowadays. But this is exactly the same demonstration described on the 1890 Spinning Tops book by John Perry, including the running off the table and bouncing on the floor:

[Jeremy McCreary]

Hmmm, this principle could be the basis of a fun new kind of bowling, but lane maintenance would be a nightmare.

I feel a LEGO knock-off coming on.

[Jeremy McCreary]

Chain bowling, anyone?



When launched at ~7,800 RPM, the short chain loops used for bowling can roll up to 3.5 m before collapsing.

A related chain accelerator running at up to 3,300 RPM enters at 3:43. See video description for details.

[ortwin]

Excellent Jeremy!
And you tell your wife the dog scratched the floor?
In science centers the big version of that standing chain is one of my favorites to play with.

[the Earl of Whirl]

That is hilarious!!!

Good job in putting that all together.

[ta0]

Perfect LEGO implementation! And you made it fast!

[ortwin]

....And you made it fast!

You really believe that ta0? 
I don't! 
I think Jeremy knows all those things already, built the LEGO  counterparts long time ago and now he is just pulling them out of cupboards as soon as we mention them.
Come on, time after time its like ten minutes later and Jeremy comes around the corner : " Oh, and by the way, I came up with a LEGO knock off of this."
Okay, once in a while like with the "blackbird vehicle" he admits that he had it build long time ago, but that I believe is just to cover up the many other instances!

[Jeremy McCreary]

Yeah, I pull things off the shelf a lot -- mainly because a lot of top ideas are, well, just inevitable. But I had the chain bowling up and running from scratch 2 days before I shot the video.

Modular construction + many parts on hand + many years building + decent feel for mechanics + very rapid guess-and-check cycles -> quick knock-offs. Fun to be able to fool around with good ideas when you see them!

[the Earl of Whirl]

You are a creativity champ!!!

[ta0]

EDIT: Merged with old topic
=============================

I was watching magic videos yesterday and I found of a guy spinning rubber bands like wheels. It remind me the spinning chain from Perry's classic Spinning Tops book.

It's at about 10:00 on this video (he spins a coin on his hand just before, what is also cool):



I need to learn this.

[ta0]

I could read his name tag on the video: he is Andrew Eland, originally from South Africa and that specific trick is called The Boomerang Band.



Edit: I mostly had it figured out from the youtube video but I decided to support the magician by purchasing a download of his DVD teaching this routine and others for $13 from this link.

[Jeremy McCreary]

I was watching magic videos yesterday and I found of a guy spinning rubber bands like wheels. It remind me this from Perry's classic Spinning Tops book....

Perry was definitely onto something.

But hard to imagine making this work by hand.

[ta0]

I had forgotten about the old topic with the spinning chains, so I merged both.