3x3 — Blindfolded
M2 for edges, Old Pochmann for corners, Speffz letters.
Choosing which edges to cycle, one pair of letters at a time. Each pair is one 3-cycle with the buffer UF, built from a commutator in the table below.
Not from your notes: written here and checked with the cube simulator. Buffer
UF (letters C and I), not the DF buffer the Reference and Practice tabs use
for M2. The method on the Corner cycles tab is the same, with edges in place of corners. Every
commutator, flip and exercise here is generated and checked by
log/2026-10-16-bld-cycles-generate.mjs.
1. From a scramble to cycles
- Find the buffer's letters. UF is the buffer. Its stickers are C (U face) and I (F face).
- Follow the buffer. The sticker in the buffer's C spot belongs to an edge. That edge's letter is the first target; the edge at that letter's spot gives the next. Keep going until the chain reaches an edge letter on the buffer's edge again.
- Pair the letters in order: (1st, 2nd), (3rd, 4th), and so on. Each pair is one 3-cycle with the buffer, from the table in section 6.
- An odd number of letters is covered in section 4.
Worked example
Scramble (edges only, slices included):
Letters from the buffer, in order:
Each frame shows the position still to solve after the pairs before it. The coloured outlines follow the edges of each pair.
2. When the cycle closes early
If the chain comes back to the buffer before every edge is solved, start a new chain at an unsolved edge. The first letter of that edge (the break letter, underlined) starts it, and the chain runs on until it reaches a letter on the same edge again. Each unsolved edge has two stickers to choose from.
The rule this site uses: pick the break letter that makes the total cheapest. If you do not remember the table, take the first letter of the edge in letter order (the Practice tab's rule).
Scramble:
Letters (break letters are underlined):
3. Flipped edges
An edge that is in its own place but flipped is left out of the letters. It is fixed at the end
with a flip row. The flip algorithm M' U M' U M' U2 M U M U M U2 flips UF and UB
in place and changes nothing else.
- Each flip row flips exactly two edges: the buffer UF and one other edge K. Each row is a setup that brings K to UB without moving UF, then the flip, then the setup undone.
- The number of flipped edges is always even, so the buffer's flip comes out right once every flipped edge has its row.
4. An odd number of letters
The number of edge letters is odd exactly when the number of corner letters is odd. The parity
algorithm R U R' F' R U R' U' R' F R2 U' R' U' swaps UFR with UBR on the corners and
swaps UF with UR on the edges. Its edge stickers are C ↔ B and I ↔ M.
Corners with an odd count: use the parity step on the Corner cycles tab. It solves every corner in the tests.
Edges with an odd count: not on this page yet. A full solve with an odd count needs a method that has not been checked, so this tab does not teach one.
5. Choosing a setup move
Choose a setup move in the same way as for corners (the Corner cycles tab, section 5). Edges have
one addition: the interchange can be a slice (M, E or S) as well as a face. The commutator
[M', U2] has four moves and is the shortest edge cycle. Its shape is a useful one to
know.
6. Look up a pair
Pick the first and second letter. C and I (the buffer) are not offered, and the second letter is never on the same edge as the first.
7. Exercises: set up, then solve
Start from a solved cube. Apply the setup scramble, look at the edges, and try the solve yourself before opening the solution. Pictures show the edges only; corners are greyed. The exercises are numbered 1 to 8 here: the odd-count exercise is left out until section 4 is settled.