PCMS

PCMS method Information about the method Proposer(s): Kenneth Gustavsson Proposed: 2008 Alt Names: KC (Kennth's Columns) Variants: Columns first No. Steps: 2 mayor, 2+3 sub steps No. Algs: 63 Avg Moves: ~45-50 STM Purpose(s): Speedsolving

PCMS (pairs, CLL, M and S slices) is an advanced method for speedsolving using columns first, designed by Kenneth Gustavsson in late 2008. The method compromises between easy look ahead and low move count (slice metric), and the result is 'decent' for both parts.

Steps:

1. Columns
   1. Solve 4 CE pairs using intuition
   2. CMSLL (42 algs), something between 2x2 CLL and CMLL (see CxLL)
2. Slices
   1. Solve centres and the RD, LD and BD edges using intuition (3x centre/edge pairs actually)
   2. Solve the FD edge and the LL edges (see E35)
      1. Orientation (5 algs minumum but here you can add more to force easier permutations)
      2. Permutation (16 algs)

Pairs:

The move count is dependendant on how well the first step is solved, if you add some extra look ahead and pair up more than one pair before you start to place them you can get as low as 10 turns for all four pairs at times. But!, the number of moves is not that important if you are speedsolving, the gripping while solving the pairs is the part where you can gain speed in this step, rather place a pair using U Rw U R' than (y') R' U R, that to avoid cube orientations. If you are speeding 15-17 turns is not uncommon, rather normal.

Pairing up is done a bit diffrent from what is used in Fridrich F2L, first find a pair, preferably one where the corner is unoriented in the U-layer and the edge is in the D-layer. If the edge is not there, then one in the U-layer is a second choise because it is easy to place in D using a single slice move. Orient the cube so that the edge is in FD or BD position, move the corner to position using a U move and then the pair is built using the M-slice. For the pairs where the corner or the edge is in bad position you have to do some setup turns to fix that, or simply use the CFOP alg for the same pair.

Example:

Scramble:

1. L2 B F U2 F' L2 B' D F' U2 R D2 L F2 L' D' B2 F U2

• p1; pieces are good, just do M2 to pair up and (z') to place.
• p2; because only one pair is solved here we can do the next from bottom and up like this: U L2 to pair and R' U (x) to place it.
• p3; nice corner, edge in U-layer so setup that one first using (y) M' then U M2 to pair up and U2 B' to place it (temporarly move the B-side to U before the B turn).
• p4; both pieces in position so: (y) U2 M2 to pair up and U R' U2 R to place.

16 moves not counting puzzle rotations, pretty normal.

CMSLL:

CMSLL is pretty much the same as CLL for 2x2x2 (or CF) but in some cases you need to use double layer turns to preserve the pairs, for example R U' R' U F' U F becomes R U' Rw' U' F' U F. In cases where that does not work any alg optimal for CMLL will do fine but with the advantage that you dont have to AUF the case so it fits with the empty M-slice, here the S-slice is equally good to use.

External links

• PCMS at Kenneth's Swedish cube page