From 2D to 3D. Can you tell what it is yet?

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Offline imatfaal

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From 2D to 3D. Can you tell what it is yet?
« on: 10/03/2011 19:24:46 »
A Challenge to the NSRers

To explain, the net of a polyhedron is a plane diagram which shows the edges of a polyhedron which could be folded to create the polyhedron.  As shown below the cube has eleven nets

[attachment=14147]

Now I see no reason that curved shapes should not have nets too - patterns on a piece of paper that when cut out and the edges are stuck together a three dimensional shape is formed. 

The challenge is - what does the below piece of paper become when taped together.  To be clear (it doesnt show in photo) the paper crosses over itself - ie one section goes under the other where is crosses.  I guarantee it can be put together with no cutting or cheating - just quite a few bits of sellotape; and it makes a proper 3d object that encloses a distinct volume

[attachment=14149]

And as a hint - "it's all Geezer's fault"


« Last Edit: 10/03/2011 19:28:11 by imatfaal »
There’s no sense in being precise when you don’t even know what you’re talking about.  John Von Neumann

At the surface, we may appear as intellects, helpful people, friendly staff or protectors of the interwebs. Deep down inside, we're all trolls. CaptainPanic @ sf.n

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Offline Joe L. Ogan

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From 2D to 3D. Can you tell what it is yet?
« Reply #1 on: 10/03/2011 20:11:18 »
Geezer, is someone taking your name in vain?  LOL.  Thanks for comments.  Joe L. Ogan

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Offline RD

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From 2D to 3D. Can you tell what it is yet?
« Reply #2 on: 10/03/2011 21:26:44 »
« Last Edit: 11/03/2011 02:02:29 by RD »

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Offline grizelda

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From 2D to 3D. Can you tell what it is yet?
« Reply #3 on: 10/03/2011 21:53:36 »
A torus wrapped around a wine bottle. Now if we could only get the wine to go on forever.

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Offline Geezer

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From 2D to 3D. Can you tell what it is yet?
« Reply #4 on: 10/03/2011 22:16:42 »
Got it!

It's one of those truss things they advertise in the Sunday Express.
There ain'ta no sanity clause, and there ain'ta no centrifugal force ćther.

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Offline imatfaal

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From 2D to 3D. Can you tell what it is yet?
« Reply #5 on: 11/03/2011 10:39:50 »
"prismatic ring" ?, or is it a prototype for Prince's "symbol" name in the 1990's  [:)]

http://mathworld.wolfram.com/PrismaticRing.html


Nice One RD! If you have time, I would love to know your thought process - or did you recognize it from a previous example?

[attachment=14163]

As you can see it only has one outside face that loops around 3 times and forms a equilateral triangular prismatic ring with a 120deg twist

[attachment=14165]


And, of course, it's all Geezers fault because a few weeks ago he asked  can I also make a Mobius thingy with triangular cross section?
There’s no sense in being precise when you don’t even know what you’re talking about.  John Von Neumann

At the surface, we may appear as intellects, helpful people, friendly staff or protectors of the interwebs. Deep down inside, we're all trolls. CaptainPanic @ sf.n

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Offline Geezer

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From 2D to 3D. Can you tell what it is yet?
« Reply #6 on: 15/03/2011 08:15:13 »
A "few bits of sellotape"! Looks like the whole thing is made of sellotape  [:D]

(I still think the truss idea is better.)
There ain'ta no sanity clause, and there ain'ta no centrifugal force ćther.