2x3x3 Domino Cube
The 2x3x3 Domino Cube is the 3x3x2 version of the Rubik's Cube. Having only two layers, some faces can't be turned 90o because this would block the puzzle. Four faces can make just double turns, so the top and the bottom faces are always yellow and white. That's the reason why we never have to orient the pieces. The same applies to the 3x3x4 cube too.
The classic Domino Cube in the 1980's had dots on it instead of stickers. That's where its name comes from. The new QJ model has got stickers and nowadays this is the most common type.
The mechanism of the Domino Cube is quite interesting. Iside the Rubik's Cube is a 6 headed core, the 3x3x2 Cube has only 4 and the pieces are built around this. If you want to take it apart remove the cover from the white and yellow center piece and take out the screws.
Solving a Domino Cube is easier than a classic 3x3x3 solution because it has less pieces and you don't have to worry about the orientation either. There are many methods for solving the Domino Cube, here I will present an easy one. This is a layer by layer method. On the picture you can see the order of the operations and which pieces are changed with each algorithm. Note that the U and D turns are 90o rotations and the F, R, B, L are all 180o.
1. White corners - This step can be done intuitively, if you need help, here's an algorithm to switch the FRU and FRB corners:
R U R U' R
2. Yellow Corners- With this algorithm you can switch two corner pieces on the back of the top layer:
(R F U F) U' (R U F U' R)
3. Every piece to its layer- Every yellow piece needs to be grouped on one layer and the white pieces to the other according to the center pieces. Switch two edges bringing them to the other layer using this algorithm:
(R 2D F) 2D (F 2D F R)
4. Switch edges- In the last step we have to put all the edge pieces to the right spot. For this we can use two algorithms depending on the position of the pieces we want to switch.
Facing each other: R 2U R 2U R 2U
Next to each other: (F D R F 2U) F 2U (F 2U R U' R)
And we solved our 2x3x3 Domino Cube in four easy steps. Keep practicing and lower your solving time.