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 Post subject: Octagonal Prism
PostPosted: Fri Jan 18, 2008 3:49 am 
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A while back I posted a few pictures of a hexagonal prism mod, and added a few pictures of a very rough octagonal prism. I gave up on the octagonal prism for a few months as I didn't think I could make masters accurately enough to be worth producing the puzzle as the pieces are quite complicated. Finally I got back to it and after three attempts am reasonably happy with the results. I have stickered up the finished article. I am still having problems with sticker bubbling on eurethane resin, but am fairly convinced that if the resin is allowed to cure for several weeks, it is ok.


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File comment: Scrambled 2
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PostPosted: Fri Jan 18, 2008 4:00 am 
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Beautifully done. Clever work.

I love the half turn shapes.

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PostPosted: Fri Jan 18, 2008 9:08 am 
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Awesome and creative!

So what is the mech?

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3x3x3 . . . PB: 11.32 Avg: 17.33
4x4x4 . . . PB: 1:11.32 Avg: 1:27
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PostPosted: Fri Jan 18, 2008 10:18 am 
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Siraj A. wrote:
Awesome and creative!

So what is the mech?
Skewb. Just look at it.

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PostPosted: Fri Jan 18, 2008 11:44 am 
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I'm not good at distinguishing mechs. The olny ones that I am always sure about are 3x3 and the Pyraminx.

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2x2x2 . . . PB: 1.65 Avg: 5.32
3x3x3 . . . PB: 11.32 Avg: 17.33
4x4x4 . . . PB: 1:11.32 Avg: 1:27
5x5x5 . . . PB: 2:26.47 Avg: 2:36.04
Pyraminx . PB: 4.18 Avg: 8.43


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 Post subject:
PostPosted: Fri Jan 18, 2008 7:35 pm 
Siraj A. wrote:
I'm not good at distinguishing mechs. The olny ones that I am always sure about are 3x3 and the Pyraminx.


Pyraminx=skewb


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PostPosted: Fri Jan 18, 2008 7:52 pm 
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Ethan Rosen wrote:
Pyraminx=skewb


Pyraminx ≠ skewb

True they both have a 4-axis mechanism, but I don't really think the same puzzles can be made from it.

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2x2x2 . . . PB: 1.65 Avg: 5.32
3x3x3 . . . PB: 11.32 Avg: 17.33
4x4x4 . . . PB: 1:11.32 Avg: 1:27
5x5x5 . . . PB: 2:26.47 Avg: 2:36.04
Pyraminx . PB: 4.18 Avg: 8.43


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PostPosted: Fri Jan 18, 2008 8:12 pm 
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Siraj A. wrote:
Ethan Rosen wrote:
Pyraminx=skewb


Pyraminx ≠ skewb

True they both have a 4-axis mechanism, but I don't really think the same puzzles can be made from it.


It's a pyraminx with floating corners.

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 Post subject:
PostPosted: Fri Jan 18, 2008 8:47 pm 
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The relationship between Pyraminx and Skewb was debated in a previous topic about Higher Order Twisty Puzzles.

Noah's explanation is schematically accurate: the Skewb just adds four pieces to the Pyraminx, but doesn't add any new moves. That doesn't mean they're exactly the same puzzle, but they're more alike than different.

This holds true of the whole family: Pyraminx, Tetraminx, Skewb, Skewb Diamond, Skewb Ultimate. They look different, but they all have the same basic movements.

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 Post subject:
PostPosted: Fri Jan 18, 2008 10:05 pm 
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VeryWetPaint wrote:
The relationship between Pyraminx and Skewb was debated in a previous topic about Higher Order Twisty Puzzles.

Noah's explanation is schematically accurate: the Skewb just adds four pieces to the Pyraminx, but doesn't add any new moves. That doesn't mean they're exactly the same puzzle, but they're more alike than different.

This holds true of the whole family: Pyraminx, Tetraminx, Skewb, Skewb Diamond, Skewb Ultimate. They look different, but they all have the same basic movements.


Ok you guys win Ethan and Noah. (and VeryWetPaint)
:D

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2x2x2 . . . PB: 1.65 Avg: 5.32
3x3x3 . . . PB: 11.32 Avg: 17.33
4x4x4 . . . PB: 1:11.32 Avg: 1:27
5x5x5 . . . PB: 2:26.47 Avg: 2:36.04
Pyraminx . PB: 4.18 Avg: 8.43


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PostPosted: Sat Jan 19, 2008 3:19 am 
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Taylor wrote:
Dude,that is an awesome puzzles.


Also correct!

(Sorry I forget to mention this earlier!)

Not only is that an excellent piece of workmanship, the photos were insightfully chosen to demonstrate the puzzle's novel behavior, especially the half-turn pictures.


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 Post subject:
PostPosted: Mon Jan 21, 2008 12:01 pm 
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Siraj A. wrote:
Ethan Rosen wrote:
Pyraminx=skewb


Pyraminx ≠ skewb

True they both have a 4-axis mechanism, but I don't really think the same puzzles can be made from it.


However, the Master Pyraminx can be made from a skewb. ;)

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 Post subject:
PostPosted: Mon Jan 21, 2008 12:09 pm 
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reeeech wrote:
Siraj A. wrote:
Ethan Rosen wrote:
Pyraminx=skewb


Pyraminx ≠ skewb

True they both have a 4-axis mechanism, but I don't really think the same puzzles can be made from it.


However, the Master Pyraminx can be made from a skewb. ;)


Are you serious? Dang. I would have never guessed. Actually, I would have never knew the mech of the Master Pyraminx. Also, isn't the Offset skewb made from a pyraminx?

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2x2x2 . . . PB: 1.65 Avg: 5.32
3x3x3 . . . PB: 11.32 Avg: 17.33
4x4x4 . . . PB: 1:11.32 Avg: 1:27
5x5x5 . . . PB: 2:26.47 Avg: 2:36.04
Pyraminx . PB: 4.18 Avg: 8.43


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PostPosted: Mon Jan 21, 2008 3:23 pm 
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thats awesome

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PostPosted: Mon Jan 21, 2008 3:55 pm 
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The pyraminx and skewb both have a 4 axis core, which automatically makes them similar in some way.

That is a very well crafted puzzle. Kudos to you.

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PostPosted: Mon Jan 21, 2008 4:01 pm 
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I hope this helps you see how the Master Pyraminx is built.

It's such a great puzzle. I'm glad I got a chance to play with it.

First, you need to see how the Skewb goes into the H-M Tetrahedron. I'll leave that up to you.


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temp.jpg
temp.jpg [ 17.36 KiB | Viewed 4347 times ]

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 Post subject:
PostPosted: Tue Jan 22, 2008 5:52 am 
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While the pyraminx looks quite similar to the H-M pyramid, they are quite different because the skewb core and the pyraminx core operate differently.

In a nutshell the skewb has four axis of rotation that all slice the puzzle exactly in half. (I.e. the rotation planes all meet at the same point in the middle of the puzzle). This is not so for the pyraminx where the planes of rotation are all off-centre. In fact if you were to draw all the planes of rotation they would form a small tetrahedron at the centre of the puzzle rather than meet at a point at the centre.

This causes problems for modding the pyraminx because "holes" form on any extended shape which are not part of any of the puzzle pieces. This is why so many mods are made from a skewb and very few from a pyraminx despite both being freely available.

I think this is correct! Anyone feel free to correct me if I am wrong.

By the way, thanks for the kind compliments!

Tim


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PostPosted: Wed Jan 23, 2008 6:17 am 
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I was thinking about this a bit more, and its is reasonably obvious that 3 rotation planes meet in in the centre of each pyraminx face. If you connect these points together (inside the pyraminx) they form the tetrahedron as mentioned in the previous post. If you extend the planes beyond the pyraminx face (as you do when you mod by building outwards), they form a triangular cone shaped "hole" in the extended shape. If you want to build in this "hole" you have no pyraminx piece to attach to. I did consider a while back building a piece to fit in the hole with "hook" pieces to clip into the pyraminx (like rainbow cube/ dino cube pieces fit in) I am sure this is possible, but have never got round to trying it. I doubt if my building skills are yet up to it anyway!

The picture attached shows how these cone-shaped holes form. I hope it helps.

Any more experienced builders got any ideas on this and possible mods that might be made?

[Edit.] Would this make it exactly equivalent to a skewb and therefore pointless? I am having difficulty thinking about it!

[Edit.] Even if it was equivalent puzzle-wise, the mods would LOOK different to skewb puzzles so might be worthwhile.


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File comment: "Hole" Picture
pyraminx.jpg
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 Post subject:
PostPosted: Wed Jan 23, 2008 7:36 am 
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timselkirk wrote:
[Edit.] Would this make it exactly equivalent to a skewb and therefore pointless? I am having difficulty thinking about it!

It would make it equivalent to the skewb, but I'd hesitate to call it pointless.


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PostPosted: Wed Jan 23, 2008 8:16 am 
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No, I don't think it would be equivalent to the Skewb. A Skewb is a deepcut puzzle. A Pyraminx isn't. I believe you would create something like the Offset Skewb.


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 Post subject:
PostPosted: Wed Jan 23, 2008 8:37 am 
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But aren't the skweb and offset skewb functionally equivalent? I know they look different, but I can't see how the offset skweb could actually function differently from the normal skewb.


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PostPosted: Wed Jan 23, 2008 2:40 pm 
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timselkirk wrote:
I was thinking about this a bit more, and its is reasonably obvious that 3 rotation planes meet in in the centre of each pyraminx face. If you connect these points together (inside the pyraminx) they form the tetrahedron as mentioned in the previous post. If you extend the planes beyond the pyraminx face (as you do when you mod by building outwards), they form a triangular cone shaped "hole" in the extended shape. If you want to build in this "hole" you have no pyraminx piece to attach to. I did consider a while back building a piece to fit in the hole with "hook" pieces to clip into the pyraminx (like rainbow cube/ dino cube pieces fit in) I am sure this is possible, but have never got round to trying it. I doubt if my building skills are yet up to it anyway!

Any more experienced builders got any ideas on this and possible mods that might be made?


Yes, those would be functionally the same parts as a Skewb, disregarding Pyraminx's free spinning corners (which don't really do anything).

Jaap has an excellent explanation of the relationship between Pyraminx and Skewb, using the Halpern-Meier pyramid as a halfway point for discussion. Here's an excerpt:

Jaap wrote:
The Skewb is closely related to the Pyraminx, which also has 4 axes of rotation. The six edge pieces of the pyraminx correspond to the 6 square faces of the Skewb, and the four corner pieces (without the tips) correspond to four of the corners of the Skewb. On the Halpern-Meier pyramid the 4 centres correspond to the other 4 Skewb corners except that rotation of the centres is not visible. Note that the solutions below will only use turns of 4 non-adjacent of the corners of the Skewb, i.e. four which correspond to the corners of the pyraminx.


That's a clever illustration. It's straightforward to show the relationship between Skewb and Halpern-Meier pyramid, and it's straightforward to show the relationship between Halpern-Meier pyramid and a Skewb.

If it's still hard to grasp, here's something that might help: fiddle with your skewb, squeeze the corners into the cube until you identify which four corners are solidly anchored to the core and which four corners are "floating." Now observe that whenever you make a turn, the four anchored corners behave like the corners on Pyraminx did: three go right, one goes left. The four floating corners mirror that: one goes right, three go left.

The Offset Skewb provides another illustration of the same thing. In fact, it makes it easier to distinguish the two groups of corners, yet it behaves exactly like a conventional Skewb.


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PostPosted: Thu Jan 24, 2008 3:40 am 
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That all makes sense, when you take a skewb apart, the four-arm spindle clearly shows that the four "fixed" corners and the four "floating" corners are non-interchangeable in their relative positions.

I am pretty convinced that an "extended" pyraminx mod with floating pieces where the "holes" appear in the middle of each face would be equivalent in terms of solution to a skewb ultimate, i.e. the moves would be the same.

However, the look and feel of the pyraminx mod would be different to the equivalent skewb mod as the rotation planes meet in a different way. The "cuts" and stickers on the surface would change, and so there might be some very pretty puzzle variations out there for people to find and build; if the "floating" pieces can somehow be attached safely.


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PostPosted: Thu Jan 24, 2008 11:59 pm 
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timselkirk wrote:
In a nutshell the skewb has four axis of rotation that all slice the puzzle exactly in half. (I.e. the rotation planes all meet at the same point in the middle of the puzzle). This is not so for the pyraminx where the planes of rotation are all off-centre. In fact if you were to draw all the planes of rotation they would form a small tetrahedron at the centre of the puzzle rather than meet at a point at the centre.




that's exactly the images that i have in my mind just before falling asleep everynight,
that small tetrahedron in the center getting smaller and smaller to finally become one and unique interssection point of those four axis, that's cool :)

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PostPosted: Fri Jan 25, 2008 12:04 am 
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the puzzle is beautifull!!

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PostPosted: Fri Jan 25, 2008 3:04 am 
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frederic plateus wrote:
that's exactly the images that i have in my mind just before falling asleep everynight,
that small tetrahedron in the center getting smaller and smaller to finally become one and unique interssection point of those four axis, that's cool :)


Those of us who can't afford sleeping pills have to sometimes resort to extreme methods!

Actually, I do sometimes find that my life is so sad that I do wake up at night with a puzzle idea in my head! Perhaps I should not admit this.


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PostPosted: Fri Jan 25, 2008 3:38 am 
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timselkirk wrote:
Actually, I do sometimes find that my life is so sad that I do wake up at night with a puzzle idea in my head! Perhaps I should not admit this.

On this forum such things are celebrated, not something to be ashamed of :)
Great work, and Welcome!

Dave


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PostPosted: Thu Jan 31, 2008 5:39 pm 
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most of my sudden inspirations come while im in the shower, at least you can get up and start working then if its something big, I have to rinse and towel off before i can do anything

almost forgot to say get dressed, puzzle making in the nude would probably not be a good idea, especially w/ superglue and sharp tools


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PostPosted: Thu Jan 31, 2008 7:55 pm 
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QUINBLZ wrote:
most of my sudden inspirations come while im in the shower, at least you can get up and start working then if its something big, I have to rinse and towel off before i can do anything


The book Patent it Yourself claims "sudden insight" inventions often occur in the shower. It's a pleasant but boring activity (eg: there's nothing to read) so the mind tends to wander. Back to the Future got that one (almost) right.

QUINBLZ wrote:
almost forgot to say get dressed, puzzle making in the nude would probably not be a good idea, especially w/ superglue and sharp tools


At least the superglue would enable you to reattach anything you inadvertently . . . uh . . . never mind. It's simpler to just get dressed first.

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PostPosted: Thu Jan 31, 2008 8:19 pm 
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wasnt he sitting upside down on a toilet when he figured out how to make the time machine?


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PostPosted: Thu Jan 31, 2008 8:27 pm 
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QUINBLZ wrote:
wasnt he sitting upside down on a toilet when he figured out how to make the time machine?


Yeah, that's why I said it was "almost" right. Not quite. Almost.

Doc Brown fell and hit his head while hanging a clock. I think he might have been standing on the toilet, but I don't remember anything about being upside-down.

Oh well, you caught me in a slight fib.


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PostPosted: Thu Feb 07, 2008 9:34 am 
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I have been asked to put a few more detailed pictures of this puzzle up that are less compressed than the first ones. I have included a couple of more detailed pictures of earlier puzzles too rather than dig up an old thread.


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Oct 1.jpg
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Oct 2.jpg
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Oct 3.jpg
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Hex 1.jpeg
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Hex 2.jpg
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Hex 3.jpg
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Skewskewb 1.jpg
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Skewskewb 2.jpg
Skewskewb 2.jpg [ 47.69 KiB | Viewed 2757 times ]
Skewskewb 3.jpg
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PostPosted: Thu Feb 07, 2008 11:08 am 
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The SkewbSkewb is a very nice design. I like that one the most.

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PostPosted: Thu Feb 07, 2008 1:29 pm 
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beautiful cubes! I can't wait to see more

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