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4x4 Edges

pjk

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This is similar to the other thread, but I have a quick question about pairing up edges quickly on the 4x4. What is the best place to learn how to do this? It takes me around 3-4 minutes to pair up the edges, and I know it can be done in well under a minute. What do I need to learn? Thanks
 

pjk

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I was working with the 2-at-a-time method. I watched Franks video, but I couldnt understand it 100%. He said you replace the solved pair and when it slices back, it will solve. But when I try to replace the pair, it messes up the centers, so I am doing it incorrectly. What algs. are there to replace them, etc? When you are replace a pair, is the other pair being moved to a certain position? Thanks
 

dougreed

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Originally posted by PJK@Apr 30 2006, 06:46 PM
What algs. are there to replace them, etc? When you are replace a pair, is the other pair being moved to a certain position?
There's nothing magical about pairing two edges at once.

The idea is this: Say you have two unpaired edges in the FR and FL positions such that doing d' pairs up an edge is the FL position. To preserve this edge, you have to kick it out into either the U or D layer and move in an unsolved edge. Say, for sake of example, that the UF edge is unsolved. Simply doing a L' U L from this position will move the FL edge to the U layer and move the unsolved UF edge into the FL position, so you can undo your initial d' with a d and fix the centers.

Hopefully that made sense. Well, the 2-edge approach is essentially the same thing, except after you fix your first edge (with, say, a d') you replace the FL edge with the unsolved edge that will fix the FR edge when you undo your initial move (which in this case was a d') with a d.

-Doug
 

pjk

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Okay, I still cant get it. I understand the concept, but it isnt working for some reason. On the video off bigcubes about the 2-at-a-time, he first gets them lined so that a slice will pair them up. I can do that. Then when he pairs them, all the centers are messed up, and I understand that a back-slice will fix it. But how do you get the back-slice setup? When I do the slice to pair up, and then replace it so a back-slice will fix it, I end up rotating one or two of the centers. Maybe I should practice a little more. It just looks real easy, yet I cant get it.
 
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