Part 1: In this step
you're going to finish making your scrambled 4x4x4 cube into a scrambled
3x3x3 cube. In this step you're going put all the edge pieces next to their
corresponding edge pieces and make one solid edge group for each pair. Once
you've solved all the edge groups you'll be able to solve your cube as if it
were a normal rubik's cube (3x3x3), except for a few situations which I will
tell you how to fix in step 3. This step will not take long to explain as it
is basically the same idea done repeatedly. First you have to know what parts
of the cube are going to do what.
Edge Groups
This diagram shows where all the edge groups are on your
cube once it is solved
Although it may seem like this step is going to complicated
it actually the easiest one in my opinion. First of all here is how you
should "view" the cube when you look at it.
Any edge groups in the U or D faces you should
think of as stored. In the first step when you set a center
piece row in the u slice this is the same type thing for this step.
Once you solve an edge group put it into the U or D face. Once
an edge is in either the U or D face then make sure not to use
it again. Once they are stored you can just leave them alone. The stored
edges are represented by the medium dark gray in the diagram. All the dark
gray edge groups are the working edges. These are the ones that you are going
to do the actual work with. It is in this "middle section" of the d
and u slices where you will solve the edge groups. Now on to the moves
for solving the edges.
Part 2: Before we even
start you need to store any solved edge groups that you have (put them in
either the D or U faces). Now you need to solve all the other
edge groups. Basically what you need to do is get two pieces, that are
seperated, from the same edge group and put one in the u slice and one
in the d slice and then solve them from there. The basic strategy for
this step is to solve an edge group and store it in either the U or
D face. Then just pick two more edge pieces, which belong in the same
edge group, and solve them. Each time you solve an edge group and store it
then just move on to another edge group. Once you've solved all the edges
except for the four working edges you'll need to use another set of moves to
solve the last four and then you'll be ready to move on to step 3.
1. To put a solved edge group into the
D or U face there are two moves you need to know.
The darker gray edge pieces in this diagram and in the
following diagrams represents an unsolved edge
group
Make sure when doing this move that you have an
unsolved edge group in the same position as the dark gray edge pieces in
the diagram. Now from here do the move L ' U ' L. This will move the
solved edge group to the U face and then replace it with an unsolved
edge group.
Make sure when doing this move that you have an
unsolved edge group in the same position as the dark gray edge pieces in
the diagram. Now from here do the move L D L '. This will move the
solved edge group to the D face and then replace it with an unsolved
edge group. The d slice is moved a lot during this step and at times
your cube will not have the centers solved but in rows. Once you've solved
all but the working edges will you solve the centers again. Just make sure to
do the moves carefully or the rows will be split into their original pieces
and then you have to solve the centers again.
From here hold the cube as in the front view diagram. Now do
the move d R U ' R ' d '. What this move does is to solve the edge
group, then move it to the U face and replace it with an unsolved edge
group. Finally the last moves restores the centers. Your cube should now look
like this,
Front View
Back View
Now you're done with this edge group so don't even pay
attention to it anymore and move on to the next group that needs to be
solved.
While holding the cube as in the front view diagram do the
move d ² R U ' R ' d ². This move does the same thing as the
one above which is to first solve the edge group, then move it to the
U face and replace it with an unsolved edge group. Then the last moves
restores the centers.
Your pieces may not look exactly like the diagram but if they
are in the same layer, either the d or u face, then hold your
cube so one of the edges is in the darker gray area on the diagram below (it
will either be in the u or d face but make sure it is still in
the position of the darker gray area),
Now do the move L ' F U ' L F '. This move will flip the
edge group so that now the edge piece should be in the other layer. If it was
in the d slice it should now be in the u slice and vice versa.
Now just do the move above that corresponds to your cube.
III. In the above two diagrams the edge
piece that is not in the U face may be in the d face
instead of the u face. If this should happen then use one of the two
moves above to get the edge piece from the U face into the middle
section. After a few times of doing these moves you'll learn which one works
for which scenario. If for any reason when you move a piece from the top
layer to the middle section and it is flipped from the way you need it to be
then do the move from #4
6. Now you should have 8 edge groups
solved and spread out in the U and D faces. These next moves
will show you how to solve the working edges. The basic strategy is to solve
two of the edges and then to use a certain move to solve the last two at the
same time. Before you do any of these moves make sure that you've solved the
centers back. Sometimes while solving the first 8 edge groups the centers
will be split apart (but only in rows if you do it right). After you've
solved the first 8 edge groups turn the d slice to fix them again. If
for some reason the centers got mixed up and they aren't in rows anymore then
you have to go back to step 1 and fix them all
over again :-(
*NOTE* In the following diagrams the darker gray now
symbolizes a solved edge group
Front View
Right Face View
Now hold your cube as in the front view diagram and do the
move d R F ' U R ' F d '. This move will move the blue-yellow piece
from the edge group on the left over to the right, then the next few moves
flips the edge group on the right, once it is flipped the last move will
restore the centers and it will solve both edges at the same time. Now you
only have the last two edge groups to solve so go to
#7.
Your cube may be in the same position as above except one of
the edges is flipped like this,
From here do the move from #4 to
flip the edge on the left then solve it with the move above.
II. Your cube may already have one of the last four edge groups solved so that now you only
have three scrambled edge groups. First you need to pick one of the edge groups, any one of them, and choose one of the pieces (for the move to solve
the edge group both pieces need to be in the u face so it helps to choose a piece already in the u face so you don't have to flip it). In
the diagram say I chose the orange-blue piece. Now you need to find the other edge of the same color and put it in the u slice as well (if
it is in the d face just do the move from #4 to flip it). Once you've done that hold your cube as in the front/left
view diagram and do the move d ' L ' F U ' L F ' d. This will move the bottom piece from the right side edge group over to the left and replace it with the other blue-orange
piece. The last moves solves the edge groups and restores the centers.
From here hold the cube as in the front view diagram and do the move d ² R F ' U R ' F d ². Don't worry if you don't see
the solved edge group it is on the other diagonal of the cube now. What this move does is put the piece on the front right edge group and move it next to
the one on the diagonal edge of the cube to solve it. Now you're about finished, go to #7.
7.Now you only have one move left and you'll be done with step 2. Your cube will now look something
like this with only two edge groups left to solve (*NOTE* the colors on your cube may be different as you may have solved different edge groups in the
process of this step but the move will still work). Your last two edges will either be adjacent to each other or on opposite edges of the cube.
I.If your cube has the last two edge groups adjacent to each other then using the
move from #4 get the last two edges to look like this
Front/Left View
Front/Right View
From here hold the cube as in the Front/Right View diagram and do the move d R F ' U R ' F d '. This will move the white orange
piece to edge group on the right then flip that edge group. The last move restores the centers and solves the edge groups.
II. If your cube had the last two edges on the opposite diagonals of the cube then using the move from #4 get the last two edges to look like this
Front View
Back View
From here hold the cube as in the Front view diagram and do
the move d ² R F ' U R ' F d ². This will move the white
orange piece to the other edge group, then flip that edge group, the last
move restores the centers and solves the edge groups.
Overview
Your cube should now look something like this,
Front-Top View
Back-Bottom View
Your cube is now a scrambled 3x3x3 cube. There are a couple
of positions that can't occur on a normal 3x3x3 that I will go over with in
step 3. You've made it this far, only one more step to go!