Monday, January 11, 2010

Step 4: Five Corner Pieces

At this point, we have placed and oriented all 12 edge pieces. The corners remain. In this step, we use a number of Corner Piece Series to place and orient 5 corner pieces. These can be any 5. It makes no difference where they are, or what colours. As long as there are 5 positioned correctly, it's good.


Recall from The Corner Piece Series discussion that


Three corners on the upper face will move in order about a triangle on the top face


If the first upper face turn is clockwise
  • the corners move anticlockwise
  • the upper front right corner doesn't move
If the first upper face turn is anticlockwise
  • the corners move clockwise
  • the upper front left corner doesn't move
Generally, it's a good idea to look for any corner piece which can roll over a cube edge into place. Here is a video showing a number of examples of placing corners.







Once 5 corners have been placed, it's time to move to the End Game.

12 comments:

  1. This is far clearer than Phillip Marshall's page. But one question: What is the easiest/best way to handle when you have a corner piece in the correct position, but with the wrong orientation?

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  2. @Marc: When you get two such corners that need to twist in opposite directions, you do a routine that twists two corners in opposite directions. Alternately, you can move the twisted corner out of place and put it back oriented correctly. Which is best? It depends on if you know how to twist corners or not! :D

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  3. @Marc,

    Bud's second way is easiest. Just find a corner which does need to move and do that one. Eventually, if you have 3 corners left and all 3 are in position but wrongly twisted, just do a CPS with those 3, which will move them around. Then, you'll be able to do the end game.

    Remember, on a 3x3x3, you can't get down to only 1 corner needing to be twisted. You can get the case of two corners being in position but twisted. If that happens, do a CPS using those two and another (solved) corner. Then you'll be able to do the end game.

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  4. This was the easiest and most fun section yet. :)

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  5. I have a problem where 4 pieces remain unsolved and none can roll over an edge piece into position.

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  6. @zachary

    There are two options.

    1) Simply do any corner piece series using any 3 of the 4 corners available. This will almost certainly provide a corner which can roll over.

    2) Find a corner which will cross the diagonal. Treat this as piece 1. Then find two others which will complete the series.

    I've updated the page to reflect this.

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  7. Whenever I move my corners around, they are in they are in the right place, but never flipped the right way! How do I fix that?

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    Replies
    1. Hi,
      It sounds to me as though you may not have read, or understood the page "What's a Corner Piece Series". You just need to read and view that so that you understand how to make a corner land in the orientation you need it to.

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  8. Hi there,

    very interesting method of solving the cube. I begun solving the cube by myself without any help a year ago. After I solved him I searched for methods. I learned the Beginner method and Roux. Speedcubing is uninteresting for me, so I searched for a method where solving the cube more intuitively than with algorithms was needed. Then I found this method.
    It's very hard not to think in algorithms, but yesterday I was busy with the cube for 3 hours to understand this method. The last week I gave up at this step because I couldn't understand him. But the method is very addicting so I kept myself busy yesterday and I think I got it.

    I have one (maybe two ;)) questions...
    There're 8 corners in total. How do you start? Do you look at every single corner and when you've found one, do you place the corner directly?

    If you have one corner on top and one at the bottom in the right slots. There're 3 left to make. Now it's a bit difficult how to archive this goal.
    You've to watch not to destroy the already placed corners. I think that's the challenge in this method to "see" what to do. When I do this step correctly (takes some time), there's still one corner left. What am I doing now without destroying the other 2 solved corners at top and bottom?
    What are the steps you use to place the corners? Or do you just do? :)
    As you can see... Starting with algorhitms and methods which require algorithms is a (in my opinion) huge drawback in learning such an intuitive method.

    Hope to hear from you!
    Best regards
    Ben

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    Replies
    1. Hi Ben
      Great questions.

      When you start on the corners, all you're doing is looking for any corner which will roll along an edge into place. There's bound to be at least one of them, probably more. Once you've found that corner, that corner becomes piece 1, and the position it rolls into becomes piece 2. Then just use any other corner for piece 3.

      Keep going like that until you're down to 3 or 4. If you can't find a corner which rolls along an edge into place, a corner which needs to go across a diagonal into place is also fine.

      Once you've completed some corners, the only thing you need to do so as not to undo them, is to make sure you don't involve them in the next corner piece series. You can always just move the corners done at top and bottom out of the way temporarily. If you can't remember what moves you did to move them out the way, write it out. Initially, I had to write down my setups. Now I never have to because it becomes ingrained.

      Once you're down to 3 corners, you go to the endgame step. If you happen to overshoot and find only 2 corners left, in place but not oriented correctly, just use those two corners and one other corner and do a corner piece series. This will leave you with 3 corners left and the endgame.

      Does this help?

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    2. Hi chareaves,

      yes you helped me out, thanks. The crucial point was the 'hiding' of the already solved corners. I forgot that setup move completely :D. At the moment I've 3 corners solved... Let's see if I can get further :).

      The case where the piece has to move along the diagonal of the triangle, I never encountered before. It seems that case ain't that often right!?

      I know how hard it is to explain this technic, but you do very well!!!
      If there're problems, I'll write in here.

      Thank you and I try to get the 4th corner now ;)

      Best regards
      Ben

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