3-Color Method

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3-Color method
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Information about the method
Proposer(s): Michael Feather
Proposed: 1980
Alt Names:
Variants:
No. Steps: 4
No. Algs: Basic method: ~ 12, Advanced method: hundreds?
Avg Moves:
Purpose(s):


3-Color Method is unique solving 3x3x3 method developed independently by Michael Feather in 1980. Method name is derived from the 3-Color Cube, which is a Rubik's Cube having tri-color scheme that uses the same colors on opposite faces.

Steps

Solve corners

1. Orient corners: either think of the puzzle as a 3-Color Cube (i.e. Red=Orange, Blue=Green, Yellow=White in case of BOY color scheme) and solve corners as such, or think of the puzzle as a 6-Color Cube and orient all corner stickers in a way that they are matching either the center color or that of the opposite face.

2. Permute corners. After solving the corners as a 3-Color Cube, there are three possible cases that can be reached using half turns only:

2a. Corners can be solved on all sides (corners can be be solved in both layers of a 6-Color Cube)
2b. Corners can be solved on one pair of opposite faces only (corners in one layer of a 6-Color Cube can be solved, diagonal swap of corners is required in the other layer) 
2c. No faces can be solved (corners can be solved in neither layers of a 6-Color Cube)

For case 2b use Waterwheel sequence (R' D2' L2' F2) R (F2' L2 D2 R). For case 2c use Parallel sequence (R D2 R D2) R (L D2 L D2) L.

Solve edges

3. Orient edges: either think of the puzzle as a 3-Color Cube and solve edges as such, or think of the puzzle as a 6-Color Cube and orient all edge stickers in a way that they are matching either the center color or that of the opposite face.

Use only half turns and/or cube rotations as setup moves between every solving sequences.

When you finish this substep, the cube will be solvable using only half turns.

Restore corners using half turns.

4. Permute edges: solve the puzzle using only half turns or shorter algorithms containing quarter turns.

Pros

  • Low number of algorithms
  • Short algorithms
  • Relative low move count with a room for further improvement

Cons

  • Not suitable for speed: a lot of cube rotations
  • Each setup move must be planned beforehand, almost no room for look ahead
  • "Switching minds" between 3-Color and 6-Color Cubes takes some time to beginner

Example Solves

Similarities with Human Thistlethwaite Algorithm (HTA)

While the 3-Color Method is very different from HTA, there are some obvious similarities in that both start by solving as a 3-Color Cube and both finish by reaching a configuration that can be solved with half turns only. The 3-Color Method can be modified to work a bit more like HTA by doing the following.

After solving the corners on two opposite faces (like the 3-Color Cube), instead of solving the corners on the remaining faces, solve the edges on the two faces with the solved corners.

An advantage of doing it this way is that after solving the corners & edges on two opposite faces (as 3-Color Cube) the setups for the 3-color edge sequences can always be matched exactly when solving the rest of the cube, no need to make partial matches where only some of the misplaced facelets/stickers get fixed. Another advantage is that the cases in which no misplaced facelets can be fixed are avoided.

One other difference is with the solve order of 6-color corners in relation to 3-color edges. When solving this way, the corners should only be solved after the edges otherwise the above advantages have exceptions.

External Links