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5×5: Centres and Edge Pairing

Fixed centers hand you the color scheme back — build them in bars, then pair every edge with freeslice.

≈ 14 minAfter: 4×4: Edge Pairing

What you'll learn

The 5×5 is your 4×4 toolkit with one gift attached: an odd layer count. Odd cubes have a true middle layer everywhere, so every face carries a fixed center sticker again — just like the 3×3. Same plan as the 4×4: build centers, pair edges, solve as a 3×3. Only the sizes changed.

One notation addition: a number in front of a wide move widens the grab. Rw still turns two layers; 3Rw turns three.

3Rw on a 5×5 — three layers in from the right, turning as one.

Centers: three bars each

A 5×5 center is a 3×3 block of nine stickers — one fixed, eight to place. Don’t place them one by one; build bars:

  1. Middle bar — a line of three through the fixed center.
  2. Side bars — build a line of three on a free face, attach it beside the middle bar. Repeat on the other side.

Order: white → yellow → the ring. Solve white, then yellow directly opposite. Then hold white and yellow on left and right — the four remaining faces form a ring around the cube, and every move you make stays on unsolved faces. Finish the ring one center at a time; the last two complete together.

The insert: taking a piece away and putting it back

Sooner or later a centre piece you need is on a face you have already finished, and you cannot just turn that face to fetch it. The move is always the same shape: take a column away, do the one turn you actually wanted, put the column back.

Rw U Rw' — lift a column of the front centre into the top, turn the top, lower it home.

Why it is safe: Rw carries a whole column away, U only touches the top layer, Rw' carries the column back. Every piece the grab moved that the middle turn did not touch returns to the exact slot it left — measured, the R, L, B and D centres come back untouched. The only pieces that end up somewhere new are the one you wanted to move and the one you displaced to make room.

Those three beats are the whole tool, and the only thing you choose is the grab: Rw, 2R, M and Lw' all give the same shape, and which one you reach for is decided by the column your piece has to land in. That is searched rather than claimed — on a 5×5, nothing shorter than three moves moves a piece between two centres while leaving the other four whole.

The last bar: grab twice

One grab always throws something out. Usually you do not care, because the target face is still half-built and the piece it displaced was going to move anyway. On the last bar you do care: the only thing left to displace is part of the bar you just finished.

The answer is the same insert twice, in two different layers — and this is the pattern J Perm walks through move by move rather than naming, because there is no single string to name:

  1. Line the piece up on top, over the column it has to land in, and grab it down.
  2. Turn the top so that what you just displaced sits over a different column.
  3. Grab that column down too.
  4. Turn the top back, then undo both grabs — first one, then the other.

The second grab is the whole trick. It parks the first grab’s damage in a column that gets restored on the way back out, so both unfinished faces come back whole apart from the one piece you meant to move. Aim it the same way every time and it works for any piece, which is exactly why it is worth learning as a shape and not as a sequence.

Edges: a midge and two wings

Each edge slot holds three pieces: the midge in the middle — this is your 3×3 edge — and two wings flanking it. An edge is paired when both wings sit beside their midge, matching colors on both faces. Twelve edges to pair, then the cube reduces to a 3×3.

Freeslice pairing

Pair edges with inner-slice turns, and don’t repair the centers in between — that’s the “free”:

R U R' F R' F' R — the front-right group turns over in place. The four top groups move one place round, intact.

You already know most of it: the last four moves are the second insert above, and the first three are the first insert with the middle turn reversed. Seven outer turns, and that is what makes it safe — an outer turn carries both wings of a group together, so this algorithm is mechanically incapable of breaking a pair you have already made. Fire it whenever a wing faces the wrong way. It is also the same seven moves on a 4×4 — nothing in it counts layers, so there is no wide-move trap to fall into.

The top and bottom layers hold eight finished edges between them; the rest pair in the middle as you go. When only two unpaired edges remain, there is nowhere left to store spares — the last two groups get their own treatment, next lesson — the same flip, aimed by hand.

Cases in this lesson

Practice

Set the trainer to 5×5 and drill centres alone: scramble, solve all six, scramble again. Centres are often half the solve, so this buys more time than any algorithm in the course.