5x3x3 and 7x3x3 Rubik's Cubes (3x3x5 and 3x3x7 Cuboids)

The 3x3x5 and the 3x3x7 are extended versions of the Rubik's Cube. Seen from above they look like a normal 3x3x3, but they have 5 or 7 layers instead of 3. They are some of the most popular cuboid twisty puzzles, and if you can solve a 3x3x3 and a 3x3x4 Cube, you already know most of what you need.

 
A 3x3x5 and a 3x3x7 cuboid in the solved state

Two Kinds of 3x3x5: Cubic or Cuboid

Not every 3x3x5 looks like a tall block. There are two very different designs, and they behave differently.

The Cubic Version (Thin Layers)

These puzzles are not really fully functional 5x3x3 and 7x3x3 puzzles because there are thinner outer layers. The extra layers are squeezed into the shape of a normal cube, so it looks like a 3x3x3 with a few thin slices on the top and the bottom. The first cubic 3x3x5 was designed by Adam Cowan, printed with rapid prototyping and published in 2007, and the mass production started at the end of 2009.

These Cube4You versions what you can see on the picture come in a DIY kit so you have to put them together and apply the stickers. They have very good quality, and you can choose between white and black bodies. You can play with them without watching any tutorial to see how far you get without help. You can use this puzzle just like a classic Rubik's Cube if you don't mess up the tiny pieces: in fact the cubic design allows some moves that a real 3x3x5 wouldn't, so it behaves more like a bandaged puzzle.

The cubic 3x3x5: the extra layers are thin slices on the top and the bottom

The Real Cuboid (Shapeshifting)

On a real 3x3x5 every layer has the same thickness, so the puzzle is a tall rectangular block, almost twice as high as a Rubik's Cube. The 3x3 layers turn like on a normal cube, but if you turn one of the long sides by 90°, the layer sticks out and the puzzle changes its shape. That's why these cuboids are called shapshifting cuboids. A half turn (180°) keeps the block shape, so if you want to avoid the chaos, turn the long sides only by half turns.

A 90° turn of a long side makes the 3x3x5 change its shape

WitEden released fully proportional 3x3x5 and 3x3x7 cuboids. Their 3x3x7 was the first mass-produced fully functional 3x3x7, where every layer can be turned. If the puzzle loses its shape, the first step of the solution is to turn it back into a block, just like on the Square-1.

Variations of the 7x3x3

There are more complex versions of the 7x3x3 Cube, for example the Super 3x3x7 has a circle in the middle to make it more tricky, and the Full Function 3x3x7 II Cube has got thin pieces in the middle layer too. The WitEden Crazy 3x3x7, sold by Meffert's in 2011, adds a circle where the circle turns with the top layer and the bottom layer turns around it. WitEden also stacked 3x3 layers even higher, up to a 3x3x9.

Pieces and Numbers

Both puzzles have the same 8 corners as the Rubik's Cube. The difference is in the edges and the centers: the four long edges and the four long faces get longer with every extra layer.

On a real cuboid the long faces show 5 or 7 rows of 3 stickers, while the top and the bottom are classic 3x3 grids.

How to Solve the 3x3x5 and the 3x3x7

The solution of a 3x3x7 Cubic Puzzle is like a 3x3x3 and a 3x3x4 Cube combined. As you can see on the picture, the inner thin layer has to be solved like a classic Rubik's Cube watching only the colors of the inner thiny pieces, then the outer layers behave like the outer pieces of the 3x3x4 Cube.

1. Restore the shape if you have a shapeshifting cuboid, so every layer is aligned again.
2. Solve the inner 3x3x3 with the beginner's method, looking only at the inner layers and ignoring the extra slices.
3. Solve the outer layers like the outer pieces of the 3x3x4 Cube, turning the long sides only by half turns.

The 3x3x7 is not harder than the 3x3x5, it just has two more layers to repeat the same steps on. If you get stuck with the half-turn-only moves, practice on the 2x3x3 Domino Cube first: it works with the same restrictions.

It's quite an interesting puzzle, it's worth buying one because it's a 3-in-1 Puzzle and has very good quality. You can find more cuboids from the small 2x2xN towers to the bigger cubes in our twisty puzzle collection.