Icosahedron 92

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Pio2001
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Icosahedron 92

Post by Pio2001 » February 27th, 2014, 12:50 pm

I recently posted about some Vinco puzzles that I had ordered in late 2013. I kept the best one for the end : the Icosahedron 92.

Image

This puzzle has been available for some time with beautiful colours. But I had to wait for christmas in order to get one, and the copy that was then available was all in beech. The advantage is that, with all the balls in the same colour, the challenge is the hardest.

In his french puzzle blog, my friend Jean-Baptiste writes about it "At first sight, I wouldn't have given a dime for this thing. But it appears to be extremely interesting".
http://jeu-et-casse-tete.blogspot.fr/20 ... laume.html

Indeed, one would be mistaken to think that this puzzle is just a bunch of balls put together by means of identical rods. A picture showing the puzzle with some pieces removed reveals the internal structure.

Image

There are four different kind of pieces. The structure is based on a cube made of 8 balls linked with 12 rods. Around this central cube, come 42 pieces made of two balls glued at both ends of a rod. There are three kind of these : small, medium and large.

The way an icosahedron can be related to a cube is not easy to visualize to begin with. I disassembled the puzzle without looking what I was doing. Then, I decided to use the picture of the assembled puzzle as a guide in order to rebuild it. Fortunately, the picture is printed on the box, because I lost the solution among all the christmas papers that were at home !
I spent about two hours just staring at the picture, mentally trying to find a way to fit every piece into the final shape. After having found a way that seemed correct, I tried to assemble everything, but failed. Two times... until I noticed that putting together given groups of pieces first helped stabilize the construction. That was the good solution. The puzzle must be assembled following the proper method, inserting every piece at the right moment.
This is an original, and quite brillant puzzle in my opinion !

The puzzle has also been made with various colour schemes. Some should help finding the solution, some not.

Václav told me that he wrote an article about his Icosahedrons in the CFF magazine. Has someone read it ?

The smallest icosahedron made by Vinco is the Kiss, but it has nothing in common with Icosahedron 92. The Icosahedron 42 (42 balls) takes advantage of the same geometric properties as the Icosahedron 92, but the puzzle looks much more basic, with 6 pieces only, each piece featuring 7 balls glued together.
Above the 92, there are Icosahedron 162, Icosahedron 252, Icosahedron 362 and Icosahedron 492, with respectively 5, 6, 7 and 8 balls on each edge of the icosahedron. I didn't see any of them, but I think that they are natural extensions of the Icosahedron 92, that is the smallest one taking full advantage of the structure discovered by Vinco.

Summary : Original, complex puzzle combining cubic, hexagonal and icosahedral geometries.

Type : Interlocking
Difficulty level :
Beginners and casual puzzlists should disassemble the puzzle watching carefully what happens.
Expert puzzlists can try and assemble the puzzle from scratch. Expect several hours.
My rating : 5/5

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