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Author Topic: Why the tall spheroconical shape of the typical Western throwing top?  (Read 3623 times)

Jeremy McCreary

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A dumb question for our many world-class throwing top experts, from someone who's never thrown a top...

Unlike the Malaysian gasing and Japanese chongake (chonkake?), the classic Western throwing top commonly has a body made up of an inverted cone below and a cap above, with the cap approximating a portion of a sphere or spheroid. The term "spheroconical" introduced in another recent thread describes this shape well.

The typical Western top is also "tall" in the following sense: If one defines the aspect ratio of a top as L / R, where L = total axial length (cone + cap, excluding tip), and R = maximum radius, then it seems fair to say that L / R > 1 or even L / R > 2 characterizes many if not most Western throwing tops.

Question: What drives this very common high-aspect spheroconical shape?

To put the question in perspective, consider high-performance finger tops designed for very long, very smooth spins. For very sound engineering reasons I won't go into here, these tops tend to consist of a stem, rotor, and tip with the lowest possible center of mass (CM) and as much mass as possible in the rotor itself. The rotor typically approximates a solid or hollow cylinder (or some combination thereof) with L / R < 1, and not uncommonly with L / R << 1.

Long smooth spins are also desirable in throwing tops, but Western throwing tops turn their backs on this geometry in favor of the high-aspect spheroconical shape. What's the rationale? Does it have to do with string handling or the repertoire of tricks one can do with Western tops?

NB: I'm aware that Malaysian gasing closely follow the finger top design, while Japanese chongake might be viewed as falling between the gasing and the Western design. For now, I'm only asking about the last of these.

« Last Edit: September 03, 2016, 12:14:59 PM by Jeremy McCreary »
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Atomic

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #1 on: September 02, 2016, 11:04:44 PM »

Before the pros reply, I'm going to guess the shape allows to for the best mixture of weight and string handling.

Btw, have you seen this video? Also, check out the "one man and his cube vid on the same channel, not really spinning a top in the strict sense, but pretty good spinning the cube object nonetheless.

https://youtu.be/sLYazynm_1M
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Neff

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #2 on: September 02, 2016, 11:18:46 PM »

I have two thoughts, neither answering "why" really, but...

1) For me, taller tops intensify the illusion that the object is standing when it should not be standing.  A low-aspect ratio finger spinner is only tilted slightly when at rest; a tear-drop shape top is laying almost completely sideways when it is at rest.  When it is spinning, not only is it standing up, but it is also upside down with the larger mass on top, defying gravity and being awesome.  The spinning postition of finger spinners is not so unexpected, but they can certainly be mesmerizing, in a meditative way.

2) The tear-drop shape is less stable than a koma or chongake.  When regenerating a chongake you have to turn with it, because it is stable and precesses slowly. Tear-drop tops precess quicker, there is no time to turn your body, you have to continously adjust for the precession, making for faster paced play.

D) The spheroconical shape existed long before acrobatic tricks of today, so "why" it exists is still an excellent question.
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Jeremy McCreary

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #3 on: September 03, 2016, 11:05:37 AM »

Btw, have you seen this video? Also, check out the "one man and his cube vid on the same channel, not really spinning a top in the strict sense, but pretty good spinning the cube object nonetheless.

Yes, but the throwing skill in the video blows me away every time I see it. Will check out the other video later.
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Jeremy McCreary

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #4 on: September 03, 2016, 11:07:16 AM »

I have two thoughts, neither answering "why" really, but.... The spheroconical shape existed long before acrobatic tricks of today, so "why" it exists is still an excellent question.

Both of those ideas make sense to me -- especially if the shape predated the acrobatics.
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ta0

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #5 on: September 03, 2016, 11:14:53 AM »

I agree with point 1 of Chris. The tall top defying gravity is a more surprising and interesting object.

String tricks are a modern invention and I am sure had nothing to do with the origin of the shape.

A string wound around a conical shape makes a gear box: low gear when the string starts pulling at the largest diameter, high gear when it pulls close to the tip. This is more efficient than just winding the string around a stem. Yes, you can do a one layer (pancake) wind with a thicker rope and get a gear effect (as they use on large Malaysian gasings) but it is less stable.

It is possible to have the wrapping cone on the upper part of the top. But once you see one invert you probably want to reproduce that result. Although there are some traditional duration games in the world, most are target and battle games: more fun!
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Jeremy McCreary

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #6 on: September 03, 2016, 12:06:51 PM »

I agree with point 1 of Chris. The tall top defying gravity is a more surprising and interesting object.

String tricks are a modern invention and I am sure had nothing to do with the origin of the shape.

Expanding on the interesting object theory:  Relative to the typical finger top design I mentioned, the tall spheroconical shape increases CM height and transverse moment of inertia (TMI) and reduces the ratio of TMI to axial moment of inertia (AMI). Per basic top mechanics (e.g., Provatidis, 2012), this combination should (i) increase the precession rate as Neff said, (ii) reduce the nutation rate, (iii) increase the nutation amplitude, and (iv) increase the minimum speed for stable sleeping or steady precession. Effects (i) - (iii) would also make for a more animated and less predictable object, especially late in the spin, though at the expense of spin time via (iv).

Another angle:  As underscored by a recent post from Eric, the classic tall spheroconical shape looks a lot like that of an acorn, which is often proposed as the first top. Could that shape be a long-lived echo of such an origin? Wonder how the global distribution of trees producing acorns would compare with the global distribution of the tall spheroconical top shape in ancient cultures?

Interesting string considerations. High-AMI finger tops benefit from tapered stems for similar reasons.
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Kirk

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #7 on: September 03, 2016, 04:55:02 PM »

Ancient whip top designs are not too far from Western tops in shape.  And the Chinese tops in the video posted by Atomic are also similar. Perhaps the "why" is best answered as in the Fiddler on the Roof ..  Tradition

1) For me, taller tops intensify the illusion that the object is standing when it should not be standing.  A low-aspect ratio finger spinner is only tilted slightly when at rest; a tear-drop shape top is laying almost completely sideways when it is at rest.  When it is spinning, not only is it standing up, but it is also upside down with the larger mass on top, defying gravity and being awesome.  The spinning postition of finger spinners is not so unexpected, but they can certainly be mesmerizing, in a meditative way.
Perhaps this is why I usually spin finger spinners stem down. It just seems more fun.
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113

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #8 on: September 04, 2016, 12:55:42 AM »

Dear Jeremy McCReary,


I second Neff's opinion that teardrop shaped tops create the illusion of "standing". Many "finger tops", do not even look as if they are spinning when spinning. Most of them are very close to the ground, and very wide, which makes sense, but for performance value, I suspect that taller teardrop shaped tops create the illusion that Neff has described.

I would say that the teardrop shape also facilitates tricks much better than the "finger top" shape.

Dear ta0,

You say that "tricking" is a relatively modern invention in regards to tops. I trust that you know more about the history of tops, so I just want to see what you think about some things that are running through my mind.

I do not have sources for any of the things I am talking about, but maybe you know what I am talking about.

In my studies of "cicus arts" or "Jongleur" arts, I have come across medieval depictions of what look like yoyos (they could be poi or something like that), spinning plates, and think I have seen spin-tops before... Colombian tops are not something that would have been impossible to exist in medieval times, and diabolo are ancient toys, so isn't it possible that "tricking" or "freestyle" top spinning existed long ago as well? I have even heard that Napoleon played with yoyo's and that french sappers used yoyos as a form of measuring device when digging trenches. 

I would love to know what you think about this.

Thank you,

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ta0

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #9 on: September 04, 2016, 10:28:59 AM »

Quote
You say that "tricking" is a relatively modern invention in regards to tops.

The earliest reference I have seen to regeneration tricks is from 1905 in Chicago.
The boomerang with Western tops is at least 200 years old and probably older.
The Japanese have been doing some string tricks like wire walkers for about 300 years.
If you consider monobolos as tops, they are considerably older.
Pear shaped throw-tops were common in Middle Age Europe although I have not seen references to any string tricks.
Whip tops in that shape are found in Egyptian tombs from 1200 - 2000 BC. So they clearly predate string tricks.
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113

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #10 on: September 04, 2016, 09:39:53 PM »

Dear ta0,

Thank you very much for sharing your knowledge with me. That is exactly what I was looking for...It does seem that spintops are definitely a very old design.

I remember reading that fat and wax were used to make yoyos "slippery".

Would you be surprised, if you discovered that string tricks were done in medieval times? Is it plausible? I do consider monobolos, diabolos and even yoyos to be a form of top.. At least... as much as a top during horizontal regenerative play is still a top...

Thank you again!

113

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Jeremy McCreary

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Re: Why the tall spheroconical shape of the typical Western throwing top?
« Reply #11 on: September 05, 2016, 03:35:51 PM »

Thanks for all the thoughtful replies. Further thoughts...

Maximum diameter height: I tend to use "rotor" or "body" for the bulky portion of a top between the tip and stem (if any). I also think of a rotor's widest section as "high" if centered above the rotor's midpoint along the spin axis. I should have specified a "high" maximum diameter in my original question. Neff mentioned this essential spec, and I'll assume it hereafter.

The vast majority of the throwing tops discussed on this forum carry their widest diameters high, and so do most of the tops shown in D.W. Gould's The Top — Universal Toy, Enduring Pastime. (Gould's tops number in the hundreds and range in age from ancient to modern.) Pocket tops and metal pump tops, on the other hand, are usually widest around the rotor's axial midpoint. Tops with low maximum diameters (e.g., the large LEGO finger top below) were the least common in Gould's book but by no means rare.



Acorn-shaped tops? A good shorthand for "tall spheroconical rotor with a high maximum diameter" would evoke the desired image in everyone's mind right away -- and not just in the minds of top enthusiasts. We've all seen "pear-shaped" and "tear drop-shaped" used in this capacity, but the images first brought to mind are upside down, and even the "conical" in "spheroconical" has this problem. Adding "inverted" clears up the ambiguity, but "inverted pear-shaped top" is still a mouthful and lacks the desired immediacy.


Photo by David Hill via Wikipedia.

So far, the shorthand I like best is "acorn-shaped". (The "-shaped" part could be dropped in some contexts.) Nearly everyone knows how an acorn is shaped and how it's usually oriented. As oak nuts, acorns naturally hang narrow end down and are usually depicted that way off the tree as well. They're also generally depicted with high maximum diameters. The "cupule" (the rough stemmed structure at the upper end) suggests a cap with a weight ring, but acorns without the cupule still have the desired shape. Heck, they even have tips! And though I find speculation about the first top largely a waste of time, the acorn is certainly an oft-cited candidate.

Anyone have a better shorthand?

"Western" tops not so Western: As the video Atomic embedded clearly shows, acorn-shaped tops are by no means unique to the West. In fact, Gould's historical sections suggest that they've long been common if not dominant in many Eastern cultures as well -- perhaps for centuries. Moreover, when and where they originated isn't at all clear. So I'm ditching "Western" as a shorthand, at least in my own mind.

Age and prevalence of acorn-shaped tops: At least half of Gould's tops are acorn-shaped. Some date back to at least 2,000 BCE, as ta0 noted. And as Kirk suggested, many of the oldest examples are whip tops.
« Last Edit: September 05, 2016, 06:16:35 PM by Jeremy McCreary »
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