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 that would block the puzzle. The side faces can make only double turns, so the top and the bottom stickers can only be yellow and white. That's the reason why we never have to orient the pieces while solving the Domino Cube. 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 layer by layer method. On the picture you can see the steps of the solution. Note that the U and D turns are 90° rotations and the F, R, B, L are all 180°.
Please read the notation if you don't know what the letters mean.
1. White corners
We have to collect the white corners around the white center. This step can be done intuitively, just make sure the color of the side stickers match. If you need help then here's an algorithm to switch the FRU and FRD corners while the marked white corners in the bottom stay in place:
R U R U' R
2. Yellow Corners
To solve the yellow corners you can swap two corner pieces on the back of the top layer with this algorithm:
(R F U F) U' (R U F U' R)
3. Edges to their layers
Every yellow piece needs to be grouped on one layer and the white pieces to the other according to the color of the center pieces. Swap the left-bottom and the top-right edges using this algorithm:
(R D2 F) D2 (F D2 F R)
4. Swap edges
In the last step we have to put all edges to their final position. For this we can use two algorithms depending on the position of the pieces we want to switch.
1: Edges on opposite sides (back and front): R U2 R U2 R U2
2: Next to each other (left and front): (F D R F U2) F U2 (F U2 R U' R)
Congratulations, you have solved your 2x3x3 Domino Cube in four easy steps. Keep practicing and lower your solution times.