An Easy Guide to an Inutitive Fridrich F2L
Introduction: What is the Fridrich F2L?
For starters, I am by no means an expert on the Fridrich F2L, or any other aspect of cubing for that matter. As of today, June 2, 2004, I can average less than 27 seconds using a version of the Fridrich F2L that I have taught myself. This will be explained later in more detail. To simplify things, I will explain this method of solving the F2L (First Two Layers) with a simple 2-step process:
The concept of the Corner/Edge pair will be explained later.
The C/E Pair Concept
The thing that makes the Fridrich method different than other methods is what happens after you make the cross. If you cannot get that far on your own, I suggest you go find more literature on that, as I will be skipping this step in this document.
Back to what happens after the cross. Immediately after forming the cross, generally either on the bottom or on the side (many prefer the left, although I myself prefer the bottom), you being your hunt for a Corner/Edge pair. On a cube with a solved F2L, a Corner/Edge pair would be, for instance, the G/R/W corner + the GR edge, the B/O/W corner + the B/O edge, etc. Any corner and edge that go together, basically. The main thing you want to look for is that the edge is not backwards and that the corner is not rotated abnormally.
Easy F2L Pairs
Take a look at fig. 1:
Notice that Case #1 of fig. 1 is correct. The colors match up perfectly on the Corner/Edge pair. Case #2 and #3 are both incorrect, since the colors don't match up. Case #1 (and its mirror) is the simplest F2L case you will ever come across, so learn how to spot it. The solution algorithm for the first case, which should be fairly obvious, is U R U' R'. Do this slowly to see how it works. Here's another simple case you should be able to recognize:
These look like different cases to begin with, but in reality they are the same. These cases are only mirrors of each other. Likewise, R U R' will solve Case #1, and (y) L' U' L will solve Case #2. These are the second most fundamental moves you need to know. Learn these very well.
Putting It All Together
These two cases take care of just about everything you will run into, with slight modifications. Unfortunately, a randomly scrambled cube will very rarely present you with cases like this, so they take some 'molding'. Take a look at these next cases, which can all fit into those shown in fig. 1 and fig. 2.
All of the following cases can be molded into the first two cases (fig. 1 and fig. 2). Try to figure out the move on your own cube first, then highlight the answers below (you won’t see them until highlighted) and compare them to those you came up with.
1) y U2 L' U2 L U2
2) y L' U' L U
3) U' R U R' U
4) U' R U' R' U
5) y U L' U L U’
6) y U L' U' L U’
If you can get this far, then you pretty much have it made. However, there is one last case that you need to know that thus far I haven't been able to find a good way to bend to my rules. Here it is:
There it is, and it will cause you grief if you don't learn an alg for it. Here is the only F2L case I would recommend learning a specific alg for, but it is very easy:
(R U R' U') x 3
There is no substitute for practice, especially if you are trying to teach yourself an entire method intuitively. Except for the last case, I would advise everyone reading this to take nothing to heart. The best F2L you can perform is one you understand completely so keep that in mind. If you got this far, I would suggest you practice your F2L over and over with random cases, not just those presented here. There are many, many more that I didn't cover, but I think that just leaves more to be explored. Remember that this method is intuitive.