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.

Beautifully done. Clever work.

I love the half turn shapes.

Awesome and creative!

So what is the mech?

Skewb. Just look at it.

I'm not good at distinguishing mechs. The olny ones that I am always sure about are 3x3 and the Pyraminx.

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.

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)

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.

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?

thats awesome

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.

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.

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

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.

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

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.





Thomas

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.

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:



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.

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.

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

the puzzle is beautifull!!

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.

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

Dave

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

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.



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

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.

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.

The SkewbSkewb is a very nice design. I like that one the most.

beautiful cubes! I can't wait to see more