Rubik's Cubes

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I started with algorithm, and now I found how to do it without any algorithm.

There are several methods do to the first two layers without any algorithm, for example Fridrich or Petrus method. You somehow get pairs of cubies that you put together to obtain the two layers.

With Fridirch method, it does not matter if you start with a cross or not. You can improvise. If a corner or an edge is already placed, you can turn the bottom face to an empty slot and fill it from there.

When there is only one empty slot left, i.e. the two layers are done except one pair (corner+edge), you need to orient the edges. You can do it before that, but well, you can also do it just at this moment. To do so, use the top (not done) face, and the two faces around the empty slot. The edges are oriented relative to two particular faces if they are either with the right color on one face, or with the opposite color on the side.

Finally, put the last pair using the two faces that you have used as a reference for orienting the edges. You are left with a cross that is well oriented.

Now, to avoid algorithm, you can use conjugates of commutators.

Oh I love Rubik's Cubes! I've got a 3x3x3, a 4x4x4 and a 5x5x5. The 3x3x3 is my favourite and I solve it daily.

I've always been horrible at Rubik's I am really good at Words With Friends, though.

I have yet to solve more than two sides of the Rubik's cube without dismantling it and putting it together again. I tried the instructions given but I only managed about half the cube before I would get to frustrated about messing up the work I had already done in order to solve the parts I still needed to do. However I can solve most metal brain teaser puzzles with ease.

[Moved from General Autism Discussion to Random Discussion]

Well, the simplest method I think is Friedrich one. Build a "plus" on one side, with edge aligned to the centers of the 4 faces around. Then put the "plus" at the bottom. Then you can turn the upper face without disturbing what you've done. And you can turn one of the 4 faces with one quarter turn, then the upper face, then put the face back. This way you can get pairs (corner+edge) out of the bottom two layers or put pairs in the bottom two layers.

I used to be able to do it -- totally freaked out my ex and his friends.

. . .but that was years ago. I'd have to study up on it all over again to do it now.

Actually, one of the last things you do in the Friedrich method is the bottom cross. Trying to do the top and bottom crosses at the beginning only wastes time. The Friedrich method involves solving the top cross, then the top corners. Then solve the middle layer. Then the bottom cross and corners, which then solves the entire bottom layer. I solve my cube at least 10-20 times a day, and that's the method I use.

I suppose you misunderstood me. When you do the plus, you do it on the top face. Then, you can put this face in the "down" direction because you don't need to look at it anymore.

After that, I do not agree with what you say about doing the first face and then the middle layer. In Friedrich method you do it at once, building a pair on the free face (the top one) and then putting it into the slot.

If you solve the top corners first, you need special moves to insert the missing edge of the pair, or at least use a conjugate to temporarily place the empty edge with an empty corner. This is not Friedrich method, but some classical method.

Yes, and the Friedrich method uses certain algorithms to efficiently place things exactly where you need them. Past that, it's up to you to make it as efficient for you as possible. I never flip the cube until I'm at the bottom layer. And, technically, if I'm paying attention, I don't ever need to flip it at all.

If you like difficulty, you can. For me, it's clearly easier to turn the cube around after the first "+".

Some people do it blindfolded. Personally I can't.

Yeah, I've seen people do it blindfolded, as well as one-handed. The world record holder can do it in 5.66 seconds with two hands, and approximately 11 seconds with one. Insane.

Anyway, do you use pairs for the first two layers or something else ?

Please explain what you mean by "pairs."

By pair I mean an edge cubie and a corner cubie together and well oriented relative to each other. Basically in Fridrich method, you build a pair and then put it into an empty slot.

I do that on occasion, but sometimes I find it faster not to.