Once the centers are solid, a solver works on the edges. Each of the 12 edges of the cube is made of . The goal is to bring these five pieces together to form a single, matching "strip". A technique known as free-slice pairing is often used, where the solver rotates middle layers to match edge pieces without disrupting the already-solved centers.
: One of the few sites that offers a 7x7 solver , though be prepared for a solution that might exceed 2,000 moves .
[5] Demaine, E. D., Demaine, M. L., Eisenstat, S., Lubiw, A., & Winslow, A. (2011). "Algorithms for solving Rubik's cubes". ESA 2011 , 689-700. 7x7 cube solver
The first major phase is grouping all 25 center pieces of the same color onto their respective faces. The standard color order to solve them is . Step 1: The First Two Centers (White and Yellow)
Once you are down to the last four edges, you can no longer use the freeslice technique without breaking your centers. Once the centers are solid, a solver works on the edges
The outer boundary pieces of the 5x5 center grid.
Build 1x5 strips on both faces until you are left with just a few swapped pieces. A technique known as free-slice pairing is often
Align the composite edges around the bottom center.
The first major stage is to build each of the six center faces. On a 7x7, each center is a 5x5 grid. The strategy is to build 1x5 "bars" and then combine them into the larger face. Because the 7x7 has a fixed center piece, you always know which color belongs where, which actually makes this stage easier than on even-layered cubes like the 6x6.
# Apply the white cross algorithm cube = white_cross(cube)
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