Big cubes: 4x4 and 5x5
Goal: Turn a 4x4 into a 3x3 and solve the parities.
Hold your cube like the one on screen (yellow on top) and repeat the moves of each case.
Use the cube on the page: watch the cases, then practice. Turn layers by dragging a piece or with the keyboard (U D R L F B and M, Shift = prime). Rw is R + M'.
Big cubes are solved by reduction: you group their pieces until they behave like a 3x3, and then solve it with what you already know.
- Centers: on a 4x4 each center is 4 pieces. Do two opposite centers first (white and yellow), then the other four.
- Edges: each edge is 2 pieces (3 on a 5x5). Pair them up without breaking the centers.
- Like a 3x3: solve it with CFOP using only the outer faces.
The parities
On a 4x4 two situations can appear that are impossible on a 3x3. They have their own algorithm (in this notation, r and l are only the second layer, and u the second layer from the top):
On a 5x5 PLL parity doesn't exist, and the OLL one shows up when pairing the last two edges. To swap individual pieces on any cube up to 7x7, use the Kubixel swapper.