3-Color Method

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3-Color method
3-Color-Method.png
Information about the method
Proposer(s): Michael Feather
Proposed: 1980
Alt Names:
Variants:
No. Steps: 4
No. Algs: 12
Avg Moves: 75 ± 2
Purpose(s): Entertainment


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

Steps

There are 2 steps for a 3-Color Cube and 4 steps for a 6-Color Cube with the same set of algorithms (which can be found in the External Links section below if needed).

Solving the 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 a 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 on a 6-Color Cube, three possible cases can be reached using half turns only:

2a. Corners can be solved in both layers.

2b. Corners can be solved in one layer, diagonal swap of corners is required in the other layer.

2c. Corners can be solved in neither layers.

Convert 2b or 2c to 2a using an algorithm (Michael Feather calls them Waterwheel Sequence for 2b and Parallel Sequence for 2c), then continue by solving the edges (or apply 2a first and continue by solving the edges).

Solving the 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 all solving sequences.

After finishing this step, a 3-Color Cube will be solved and a 6-Color Cube will be solvable using half turns only.

4. On a 6-Color Cube, restore corners and permute edges.

Average move count in STM

Step 1 ~ 14.
Step 2 ~   9 (or ~ 12 if applying 2a).
Step 3 ~ 31.
Step 4 ~ 17.

Pros

  • Concept of edge orientation, generally perceived as being hard for beginners to understand, is avoided
  • Low number of algorithms
  • Short algorithms; average number of moves per algorithm: 5.7

Cons

  • Thinking of a 6-Color Cube as a 3-Color Cube could seem rather unintuitive at first
  • It's not always possible to exactly match the setup for a solving sequence
  • Suitable for neither speed solving nor fewest moves solving (when considering the method as it is)

Example Solves

See also

External Links