iTopSpin

We have talked before about origami tops, in particular the finger top designed by Manpei Arai (I had limited success with that one but Jim gave me a nice one.) I know Mark Magyar, daveid and others like origami so here are two more: a nice dreidel and a blow top, both designed by certain Yami Yamauchi.

Now my challenge to the origami people on the board is to make an origami top that can be boomeranged! It should be possible. Double (or triple) points if it is made from a single piece of paper.

That ta0. Always pushing us!!!

Thanks very much for sharing. The diagrams for these tops can be found here: http://www.marigami.com/yami.shtml
and here's another top from Yami-san : http://www.youtube.com/watch?v=A5aMNTAcKLs&feature=mfu_in_order&list=UL

Yesterday night I saw an excellent documentary on the PBS show Independence Lens: "Between the Folds." The Origami they show is completely amazing. I recommend watching the whole show (it is available in parts on youtube or you can order the DVD form Amazon), but at least you need to see the top that appears at 2:44 on this section:

Between the Folds, Part 4/6 www.youtube.com/watch?v=oHs5WW2aE-A
http://www.youtube.com/watch?v=oHs5WW2aE-A

Super cool top! But, is the law of conservation of momentum violated?

ta0 wrote:
Super cool top! But, is the law of conservation of momentum violated?

My guess is no.

That is also my guess, but this top challenged my faith!
I will try to build a simpler one for which I found instructions (Origami Flasher by Jeremy Shafer) and do some experiments.

Here is another one that is probably simpler than the one by Chris Palmer on the documentary but spins for a full 20 seconds!:

Self-Winding' Flashing Spinning Origami www.youtube.com/watch?v=ANT5vDuPr8k
http://www.youtube.com/watch?v=ANT5vDuPr8k

I happened to catch this program last night on PBS. As cool as the top is, the one that amazed me was the dragon that the college student spent more than a hundred hours to fold. He definitely has more patience than I do.

That is some serious Origami.......much more detailed and many more possibilities than I could have ever imagined. I'd love to jump right in and do some of this but I have the sneaking suspicion that it will take more understanding and training that I now have.

That dragon was amazing, specially because he said it was made from one single piece of paper, not cuts.

I made my first Jeremy Shafer´s origami flasher (instructions). Although mine is not very good it does work. Not so much on a table as the tip is pretty bad, but if you let it fall in the air it spins nicely. You should try it Mike, it is not that difficult.

I played with it for a while, really surprised how the whole thing ended up spinning in one direction without apparently any external torque. I certainly did not have the impression I was giving it any spin. Where was the conservation of angular momentum? It did not come from friction with the table as it spun in the air. It didn't seem possible that aerodinamic effects could give it a spin (but I don't have a vacuum bell jar to test it, yet ). So it had to be the fingers. But the action was too fast and I could not tell.

So I did the following experiment. I threaded each end of a piece of sewing thread to each side of the spinner. I pulled with the thread to stretch and open the spinner and put the thread over two posts to keep it that way. Then I used scissors to cut the thread:



(I took that photo after all the playing and testing: the top was in better shape at the beginning )
My hope was that this way the release of the tension on both sides was simultaneous and no moment could be transferred to the spinner. I repeated the experiment 3 times and there was no net spin: the top remained still after it collapsed. So it seems it was the fingers after all. But I need to make better spinners and confirm this. Perhaps some slow motion video.

I recently once again went to the page of Yami Yamauchi -Yami's Corner : http://www.spitenet.com/origami/yami.shtml
I went to get the spin top diagrams and downloaded some of the how to videos to watch later.
For a surprise, the 'Origami Square Spinners with spiral and color-changer graphics' book ebook mentioned on the bottom of the page is now available for free. different optical illusion design diagrams in the book.
http://www.lulu.com/product/ebook/origami-square-spinners-with-spiral-and-color-changing-graphics/15991572

Thanks Mark for the heads up. I downloaded the little ebook.

Here are nice diagrams of the Manpei Arai's spinning top:

https://www.youtube.com/watch?v=zJ6F6ZUlfVw
BYE LUDO

Very good tuto
Slow but easy to follow

TX

bro_jim

Yes, thanks for this. I am always fascinated with what can be done with paper and making things that spin with it are especially exciting!