HOW TO SOLVE THE 4X4 RUBIK'S CUBE

VERY IMPORTANT: YOU NEED TO KNOW HOW TO SOLVE THE 3X3 CUBE BEFORE TRYING TO SOLVE THE 4X4 CUBE. IF NOT, PLEASE CHECK MY PREVIOUS BLOGS FOR THE 3X3 SOLUTION FIRST.

       So, when you were celebrating about solving the 3x3 cube, you did not know the challenges ahead of you! The 4x4 cube is here, and it will haunt you until you defeat it! But don't worry, this will help you defeat the 4x4 cube. Are you ready? Here we go!

Symbols

       Most symbols will be the same as the 3x3 cube. When I write “R”, that means you twist the right side clockwise. When I write “L”, that means you twist the left side clockwise. When I write “F”, that means you twist the front side clockwise. Same thing with “U”(Up), “D”(Down), and “B”(Back).

But there are a few different symbols from the 3x3. You can move two layers at a time. For that, I will put a * at the end of the letter. Unlike the 3x3 tutorial I made, the counterclockwise symbol is ^.

Quick Summary

       So first, you will have to solve the four middle pieces. After that, you will face a complicated step, which is for making the 4x4 cube look like a scrambled 3x3 cube, but don't worry, you will complete that step. After that step, you just solve it like a normal 3x3 cube. Sometimes, you will face parity, a type of problem that cannot be found on the 3x3 cube. To solve parity, you will have to do a very long algorithm to solve it.

Two Middle Pieces

       The middle pieces are the middle 4 pieces of each side. Let's solve the green side first. As you become better at this cube though, you can start with any color. But just start at the green side this time.

First, you should get two green rectangles (which are basically two green middle pieces right next to each other). Since you already mastered the 3x3 cube, you should be able to get the two green rectangles easily.

After that, you can put the two rectangles together and finish one middle side as shown in Figure I.

Figure I

The next step is to solve the blue side. You should know that the green side and blue side are opposite of each other. Turn the green side to the bottom. First you will get all the four blue middle pieces into the front, left, right, or the back side. You will usually have the pieces already there, but if it is not and the piece(s) are in the top layer, you will turn the top layer to the front and depending on if the blue piece is on the left or the right, you will do these algorithms. Left: L^*, 2U, L*; Right: R*, 2U, R^*. You will keep on doing that until the piece is on the correct layers. We call this as Algorithm One. After that, you can turn the cube again so the green side is back on the bottom.

Then, you can easily put the four blue pieces into two rectangles in vertical positions. If a rectangle is horizontal, all you need is to twist that layer left or right, it doesn't matter. After that, you put one of the vertical rectangles in front of you. We expect to have the other vertical rectangle on the left or the right side. However, if you are not lucky, i.e., the other rectangle is on the back side, then you need another trick to put them adjacent. You should mess up one of the rectangles. Make sure while you are messing it up, you do not break up the other solved rectangle. To do that, you turn both the rectangles horizontal: One horizontal rectangle on the top of the middle layers, and one on the bottom of the middle layers. Then you put them in adjacent sides. Put them vertical and you are done.

Soon, you are in the step that puts the rectangles into the top side, or you should say, the opposite side of green. You need to use Algorithm One taught earlier for each rectangle. So if the rectangle is on the left side, use the left algorithm. Same thing for the right side. Just to tell you, after you finish one rectangle, you need to twist the rectangle in the blue side so it lines up with the other rectangle as shown in Figure II. And then you do the algorithm.  You should now finish both green and blue middle pieces. Check, the blue and green side must be opposites. If not, then you should mess only one side up and then start over.

Figure II

The Other Middle Pieces

       Now it is time to solve the other sides' middle pieces. The first step in doing that is to first put the green and blue side at the sides so that the unsolved sides are in the center wedge. After that, you will try to get all the middle pieces left into rectangles in different colors without messing up the green and blue middle pieces. Basically you can only play with the top layer, the bottom layer and the middle two vertical layers. The key is that once you get a rectangle, you need to put it vertical so when you try to finish the other rectangles, you won't mess up the rectangles you already solved. You might need to do this for a long time, or really fast, but I believe you will get all the rectangles finished as shown in Figure III.

Figure III

After you finish the rectangles, you need to solve one side first by twisting the middle two vertical layers. But which side to solve first, yellow, or black, or orange, or red? Try to find a corner piece that has blue (or green) on it and the piece's blue (or green) side is on its color side, i.e., the blue (or green) side. Then find the other two colors of that corner piece, say black and red. This corner piece is shown in Figure III as well. Choose one of the colors as the side you want to solve first, say red. Then combine the two red vertical rectangles into one side and twist the layer that has the corner piece so that the red piece is on this (red) side, as shown in Figure IV.

Figure IV

Next we will solve the other color side, i.e., the black side in our example, which is indicated by the corner piece already. You can line up the two black rectangles as shown in Figure V, and use Algorithm One just as in the step we solved the blue middle pieces. Please be careful that you need to put the black side on the top and the other black rectangle on the front (as shown in Figure V), when using the algorithm.

Figure V

As you finish your fourth middle part, there will be only two more middle parts unfinished. Just line up the rectangles and use the same algorithm. To figure out which side is which, just look on the opposite side. Opposites: Black (or White if White is in your cube)-Yellow, Orange-Red, and Blue-Green. So when you try to solve the side for example, you know which side should be on the top. And...congrats!  You finished all the middle pieces in the 4x4 cube!

Make it 3x3!

       Now the next step is to make the scrambled 4x4 into a scrambled 3x3! You will have to get two edge pieces of the same color together (an edge piece is a piece on the edge but excluding the corner pieces). Then, you will pretend that two edge pieces that are together are one piece on the 3x3 cube. Therefore one finished middle side can be treated as one piece, the middle piece on the 3x3 cube.

Basically, you will first find two edge pieces of the same color, which are not together yet. You might be wondering: Wait, there are two same edge pieces on the cube? Well yes, there are. Unlike the 3x3 cube, the 4x4 cube has two same edge pieces. So anyway, you find the two same edge pieces. Twist the cube around without breaking up the middle solved pieces until the two same edge pieces are on opposite sides and on different layers, as shown in Figure VI.

Figure VI

Then check that the top layer has at least two unsolved edge pairs. If not, bring other unsolved edge pairs to the top layer. If you can't find another two unsolved edge pairs, I will have an algorithm later to solve that, which will be introduced later.

If the left side piece is in a higher layer than the right side piece, as shown in Figure VI, you do this algorithm: U*^, F^, and then turn the right side to the front. Next, you turn the upper layer until an unsolved edge pair is on the left side of the upper layer. Then you do F, D*, and you are done.

If the right side piece is in a higher layer, as shown in Figure VII, use this algorithm: D*, F^, then turn the right face to the front face, flip the top layer until an unsolved edge pair replaces the edge pair you are trying to solve. Then do L, D*^.

Figure VII

Sometimes, you might see the right side piece is in a same layer as the left side piece, as shown in Figure VIII. In this case, you need to do L^, R, U, F,  U^, L. Then the two pieces will be in different layers, and you can use the previous algorithms to solve it.

Figure VIII

Do the same things for all the edge pieces. Sometimes, the last two edge pairs are not solved yet. Using the above algorithms will not get it solved. For the last two edge pairs, put them on the left and right sides separately. Once you do that, make sure that the two pieces of the same color are in the same layer. If not,  you can use the algorithm introduced for Figure VIII. Then you will have to do this algorithm: D*, R, F^, U, R^, F, D*^. Sometimes, you might not need this algorithm, but usually, you do. After this, you should be able to pair up the edge pairs. Each edge pair is one piece on the 3x3 cube. The other pieces are one piece on the 3x3 cube. Then you solve it as a 3x3 cube, and you should be finished!

Parities

       Parities are a problem on the cube that cannot happen on the 3x3. To solve parities, you need a very long algorithm to solve each. There are 4 kinds of parities in all. Remember: you only need to do the parity algorithm when all the other parts of the cube has been solved.

Parity 1: When an edge pair is switched around

               2R*, 2B, 2U, L*, 2U, R^*, 2U, R*, 2U, 2F, R*, 2F, L^*, 2B, 2R

Parity 2: When opposite corners are in the wrong position.

               2U*, 2L*, 2U, 2L*, 2L, 2U, 2L*, 2U*, R, U^, L, 2U, R^, U, R, L^, U^, L, 2U, R^, U, L^, U

Parity 3: When two edge pairs opposite of each other is                      switched around.

               2r, 2U, 2r, 2U*, 2r, 2u

Parity 4: When two corners on the same side are in the                      wrong position.

              2U*, 2L*, 2U, 2l, 2U, 2L*, 2U* F', U', F, U, F, R', 2F, U, F, U, F', U', F, R

Congratulations! You are finished!

How to solve a rubiks cube 2

Second layer

    Once you solved the first layer and the green side, you need to solve the second layer. Turn the cube upside down so the blue side is up. You look around the up side and you need to find a piece in the cross that does not have a blue color, say, its top color is white and its other side is orange. You twist the top layer until that piece is in its correct side, i.e., the orange side in the example. Then you put that side to the front. Then you need to put that piece in the second layer of the same side. To put it on the right of the middle piece, do U, R, Ui, Ri, Ui, Fi, U, F. To put it on the left of the middle piece, do Ui, Li, U, L, U, F, Ui, Fi. Using these two algorithms, you should solve the entire second layer.

 

Last layer

    To solve the last layer and the entire cube, you need to look at the blue side. The blue side usually should have the backward L as shown in Figure II (note that the backward L is on the top left), the line as shown in Figure III (note that the line is horizontal, not vertical), or the cross as shown in Figure IV.

Figure II

Figure III

Figure IV

The goal is to get it to the cross. If you have the backward L, you first need to get it to the line and then you get it to the cross. If you have the line, you just get it to the cross. When you have the backward L, do F, R, U, Ri, Ui, Fi. You will have the line. Then you repeat the algorithm to get to the cross. Once you got the cross you twist the top layer until at least two edge pieces of this cross are in its correct side. Turn the cube so the two correct edge pieces are on your right side and the opposite side. Then you just do R, U, Ri, U, R, U, U, Ri, U. All the top layer edge pieces will be in their correct positions. Here’s the case when the two correct edge pieces are not next to each other. Then you put one in the front and one in the back, and do this: R, U, Ri, U, R, U, U, Ri. Then you have two correct pieces next to each other, and you can do the normal way.

Figure V

On very rare occasions, you may first have the blue dot as shown on Figure V, instead of backward L, straight line or the cross. In this case, you can do F, R, U, Ri, Ui, Fi on any side to get to the backward L. Then you can follow the above instructions.

 By now, you’ve gotten the edge pieces finished. Then you need to get the corner pieces in their correct position. To do that, you need to find a corner piece in its ready position. For example, a piece with colors blue, red, and yellow needs to be in the corner of the blue, red and yellow side. You put this piece in the right top of the front side. Then you do U, R, Ui, Li, U, Ri, Ui, L once or twice to get all the corner pieces in the ready positions. Sometimes you may not be able to find one piece in its ready position, then just start from any side with the above algorithm.

Then you find a corner piece with blue side not on the top, and turn the cube so that it is on the top right of the front side. Then you do Ri, Di, R, D a few times until all the three colors of this piece are in their correct positions. Remember, in this step, you will ruin the bottom two layers, but don’t panic. Believe me, the cube is going to come back in the end.

Then you keep the front side unchanged, and twist the top layer until another unfinished corner piece is on the top right of the front side. You do Ri, Di, R, D until it is in the right position. You repeat doing that until the corner pieces are all in their correct positions. Then you are just one step from finishing your first rubiks cube!!! I believe that you are smart enough to figure out that easy step by yourself.

Congratulations, and I hope this taught you a lot and you liked it. Thanks for reading!