Step 4: Twist the edges of the last layer
The first step of the last layer is twisting the last layer edge so that they all point up. Don't lake a look at the corners yet, that's the next step.
Again you can also watch the video from Arnaud on the right.
Now, you are probably wondering. Ok I can do 2 layers now. But how can I fix the last one without messing up the rest! This is indeed a hard task to do without help, you don't have much space to move. However with some tricks it's not that hard to solve it.
The next task is to make a + of yellow edges on the U-layer/top layer. There are 4 different possibilities for this. BUT, you can solve them all with one principle.
First you need to know what good and bad edges are. Good edges are the ones that are already twisted with yellow pointing up. The bad edges are the ones with yellow pointing sideways.
On the picture you see a cube with 2 good edges and 2 bad edges. The good ones on right and left. And the bad ones on back and front. You could also see the top layer as telephone keys. Then number 2 and number 8 are bad and number 4 and 6 are good. I will use the telephone system further to point out which cubies I'm talking about.
The algorithm
Now I will give you another algorithm, actually you already know this algorithm. It is only 2 moves extra. The algorithm is: F sexy move F' in other terms F RUR'U' F'. Note that I put a space between them to show this algorithm is build up by 2 things. You probably don't know what an F would do. You can see this on the applet below. Just like the R and the U the F moves is a clockwise turn of the front side of the cube. Of course an F' would be an anti-clockwise turn of the front side.The principle
What you must try to do on your cube is to get a good edge at the 4 (remember the telephone trick? This would be the edge on the left). And you want a bad edge at the 8 (this would be the edge on the front of the U-layer). As a matter of fact. The cube in the picture is already in the right position. If you reached this you have to do the algorithm (F sexy move F'). If not all edges are good yet, repeat this.If you have no edges pointing up yet, just do the algorithm anyway and there will be 2 twisted. Of course if all edges are already good, just move on to the next step.
good edge on 4, bad edge on 8
Here are some examples of how to apply this principle. Again this is just to show how the principle works. Don't learn the moves here, only learn the algorithm (F sexy move F').
Apparently there are some problems again with the applets. The first applet that shows the algorithm works but now it solves the whole cube which of course it mostly doesn't (or you have to be very lucky).
However you can see how the algorithm should be performed and you will also see that the edges will twist. I hope you understand it this way.
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F RUR'U' F' |
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Example 1 |
Example 2 |
Example 3 |
Sometimes you are lucky! |