Thursday, 22 March 2012

When is a cube not a cube?

..... When it's a tetrahedron...

Master pyramorphix
..... Or when it's a supercube...

4x4x4 Supercube
5x5x5 Supercube
"He's finally gone mad!" I can hear you say, "what on earth is he talking about?"

No, I haven't lost my mind! Well no more than I usually have - although these puzzles really messed with my head. They looked so innocent and I thought they would not be too hard to solve and would look particularly pretty on my shelf. Certainly the latter is true - they are truly lovely to behold but I have not found them to be in the least bit easy to solve.

I bought the Master pyramorphix from puzl where they call it a Super pyraminx, a pillowed version is also available from them called the Mastermorphix. Both are also available from Mefferts and the HKNow store. So why am I talking such rubbish and talking about cubes in the same breath as this obviously tetrahedral (pyramidal) puzzle? Because functionally it is a cube!

Suspend your disbelief for a while! It really is a 3x3x3 cube and if you can solve one of these then you should (??!) be able to solve this puzzle. The blurb on the Puzl website makes absolutely no mention of this odd behaviour of these puzzles. I bought it because I wanted something to complement my Pyraminx (a puzzle as old as the Rubik's cube, designed by Uwe Meffert), I had hoped it would be similar but slightly harder. The Pyraminx is a pretty easy to solve corner turning tetrahedron and I can solve one in under a minute - it really is that simple! When I received the Mastermorphinx I realised that it was radically different - it is an edge turning puzzle. The 2x2 version is the Pyramorphinx and the "master" version of any puzzle is 1 level up. So my puzzle is an edge turning 3x3 tetrahedron - OMG.

Aaaaaargh!
I had absolutely no idea what to do with it! So I put it on the shelf and played with some other goodies that I had bought. However, I kept looking at it and something very odd struck me - if you turn it edge upwards then it resembles a distorted 3x3x3 cube. Have a closer look at the top picture - you will see that the piece with a blue and red triangle on it could be a centre piece. Radiating out from it are 2 red and 2 blue parallelograms - edge pieces forming a cross, and finally the 2 big corners and 2 tiny triangles are corner pieces. Aha! An epiphany had struck me. After twisting bits back and forth, I was convinced I was correct and so I decided that I certainly could solve it, so I scrambled it completely and ..... I think I'm in trouble!!!

In my hands I now had a horrendously shape shifted thing and not only could I not work out how to move the pieces but I also could not even orient myself. Overall this puzzle took me about 8 hours to solve the first time. It really is a cube inside that horrific shape and gradually as you get to orientate yourself, you work out piece by piece what to do. The terribly long solve time is due to the fact that it is very easy to get lost and scramble it by accident and then you must start over. The final face also has some very strange properties - moves that I would usually use on corner orientation are used on the top edge pieces and it really took me a very long time to decide which algorithm to apply to which conformation.

Overall this is a tremendous puzzle - if you are able to solve a 3x3x3 cube and want an extra challenge then go for this. It is also a brilliant one to hand to your non-puzzling friends to watch them recoil in horror when it starts to change shape! Tony and Jas at Puzl provide great service as does Calvin at HKNow store.

Now on to the Supercubes - As you can see from the pictures these are just like normal cubes but with MUCH more colour. In fact Mrs S took one look at these and shuddered, muttering to me that those are enough to cause a severe headache. She is not wrong, they indeed caused me a headache. Not because of the colour but because of the puzzling involved - you have to pay attention to the position and orientation of every single piece.

I bought my two from Rline on the Twisty puzzles forum - he had rather an overstock and wanted to get rid of a few and who am I say no to the offer of new toys. Despite shipping 3 puzzles from Australia to the UK, they arrived in just 5 days. Whilst I mention Rline, if you are struggling with the complexity of all these puzzles and don't feel like interpreting the minimal algorithm approach of Marshall that I mentioned in a previous post then you MUST go to Rline's website. He has taken the Marshall approach and made it understandable and extended it to a huge number of other puzzles. The work he has put in is phenomenal!

So having established that this is not just a 4x4, how do you solve it? Apparently most cubers do not solve it like a normal cube ie layer by layer. Now I am far too old to learn something new! I wanted to use my existing methods and…

The first time I did it with absolutely no problems - it just fell into place! I actually thought "it's a piece of cake, what is everyone worried about?" But I had been lulled into false sense of security!!  There are quite a few real pitfalls:
  1. Getting the final 2 centres together is a bit of a bugger - in fact it fails 5 times out of 6! I had to work out an algorithm to do a 3way swap. I finally managed that after an hour!
  2. Then on to recreating the two piece edges - no problem just the usual last 2 edge issue.
  3. Finally, on to the top layer. Here you still get exactly the same parity problems as a normal 4x4 BUT fixing them caused a bit of a headache. A standard 3 edge cycle causes awful problems on the sides. I did get very confused at one point and had to put it down complaining of a real headache!!! Eventually I realised that the Domino cube (3x3x2) is the secret.
Finally it was solved in about 6 hours - I'm a genius aren't I?

Well, as it happens - no I'm not!!! I immediately tried it again and got into a position where there is a rather unique parity problem and the required 2 edge flip only causes a parity elsewhere! I went to my cubing puzzle pal Jon aka SuperAntoniovivaldi on YouTube - he has a single algorithm to do what I needed and it is horrendous! I could not commit it to memory no matter how hard I tried. I then realised that I must be maturing at this twisty puzzle lark because I developed another approach using only what I knew already and… it worked! An old man like me really doesn't need to learn anything new!!!

I can now do the 4x4 supercube in about 5 minutes. I absolutely LOVE this puzzle - it is so much more challenging and fun than a standard 4x4.

Now onto the 5x5 supercube. Gulp!!

My initial thoughts were firstly to solve it like a standard 5x5 just paying attention to centre positions. Oh no you don't!! This doesn't work at all! Then I tried to just think of it as a 3x3 within a 5x5 and solve the inner cube first - this is sort of the correct approach but the pieces aren't linked internally like a 3x3 so you can't use standard 3x3 algorithms - it is actually easier to work from face to face and then for the final 2 faces. You solve inner edges first (possibly using a 3x3x2 algorithm) and then, using a nifty little 3 corner swap just like on the 4x4 supercube all the faces are done. Next reconstituting the triple edges goes just as a normal 5x5 EXCEPT you MUST avoid the single cubie parity as the standard 5x5 algorithm for rotating it creates parities elsewhere! This can be avoided just by planning out your moves.

From here on you effectively have an odd shaped 3x3 which can be solved in the normal fashion until the top face - again there are some odd parities which can be quite fun to work your way around. This cube was solved in about 1-2 hours!

So, is it worthwhile getting these? I would say that these are even more fun than a standard 4x4 and 5x5 - you really need to pay attention to what you are doing and much of what you have learned before needs to be altered or even thrown away.

Unfortunately it is almost impossible to buy these now. Only Twisty puzzles seems to stock them. But what you could do is buy a decent quality standard cube and resticker it. The stickers are out of stock at CubeSmith but can be found at Oliver's stickers in Hungary. I would definitely say that you should buy a pair of ordinary cubes and resticker them from Oliver's stickers. Be aware that a Vcube 5 is a larger than normal size and should not be used as the base cube!

7 comments:

  1. Kevin,
    It's an old post, I know, but I would be interested in how you did the edge swap on the 4x4. You mention a 3x3x2 - is it a simple as doing cuboid-style edge swap? Would love to know before I scramble up all my hard work so far!!
    Also, just to note - I am solving a Rhombic Dodecahedron puzzle (which is apparently still just a 4x4 supercube), but it may be of interest to you and your readers that the Eastsheen supercubes are still available at www.cube4you.com - I have just received a 4x4 and 5x5 in the post today!

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    1. I honestly cannot remember what I did then! But now when I do a 4x4 supercube I solve it in a way that avoids parities - I reduce to a 2x2 instead of a 3x3. This is a variant on the Bandaged AI cube solution. It is lots more fun!

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    2. Hi, do you have a tutorial on how you do that? I have a problem with the last 2x2x2 block and every tutorial on it is for a normal 4x4 and not the supercube version.

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    3. There is plenty of help from Superantoniovivaldi try this link
      Supercube tutorials

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    4. Superantoniovivaldi is the man for this. I use his intuitive solve for Square-1 but I forgot to look in his videos for this.
      Thanks :)

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  2. I do a different way of solving a 4x4 or 5x5 supercube I start with reducing edges, then solve it without thinking about centers other than orientation for middle center of 5x5 then solving centers. This way when I am fixing parity I will not move something that is solved.

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    Replies
    1. That's a nice way to do it but you will end up with the void cube parity occasionally because you will have solved it in a place where the centres cannot go! Maybe it doesn't work out like that with a 4x4?? I'll have to give it a try myself!

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