One-Answer 4x4 Question Thread

[mafergut]

I've just been trying to learn Yau via JKC's tutorial (can be found here), and in the scramble she provides, there are some weird 2Rw and 2Rw2 moves...
Pretty sure that isn't proper notation...

What are these?
Are they equivalent to a certain move, or are they something else...?

Thanks!

From the regulations

12a2) Outer Block Moves (outer slice plus adjacent inner slices; n is defined as total number of slices to move; n may be omitted for two slices):
12a2a) Clockwise, 90 degrees: nFw, nBw, nRw, nLw, nUw, nDw.
12a2b) Anti-clockwise, 90 degrees: nFw', nBw', nRw', nLw', nUw', nDw'.
12a2c) 180 degrees: nFw2, nBw2, nRw2, nLw2, nUw2, nDw2.

In short, 2Rw2 = Rw2

 

[MattyAB]

cool thanks

So, what is a 2Rw, then?

 

[Cristobal]

Hi, I've just started 4x4x4 this week and managed to solve it yesterday (2 or 3 times), and then I got stuck at the end. The method I use, consists in placing the centers, building the edge pairs and solving it like a 3x3x3 with the beginner's method. However, no matter how many times I repeat the alg (RU' RU RU RU' R'U' R2), I got either 2 headlights + 2 solved sides (opposite or adjacent) or 4 headlights. The cube didn't pop and the pieces of the cube haven't moved. I really don't understand what's wrong. I scrambled the cube twice to start again, and always end up like this:

 

[hamfaceman]

You have parity, my good man. Read this page for more information.
https://www.speedsolving.com/wiki/index.php/4x4x4_Parity_Algorithms

 

[Cristobal]

OK, this is new to me. Thanks mate!

 

[mafergut]

Unfortunately you need to use the parity alg if there are two flipped wings on either side of a midge and the rest of the edges are solved.



You should only put lube on a few pieces, not the entire cube. Usually you can do two pieces on one side of the cube, and 2 pieces on the other. But you should put a small amount at first, and put more in as you see fit rather than putting a ton of lube in.



For when the corners are diagonally swapped:
So if you know the PLL parity alg (I use Uw2 Lw2 U2 l2 U2 Lw2 U2, or you can replace any moves involving the left side with the right) you simply do that alg, then an N-perm. You can also do a Y-perm, U2, R U R' U', PLL parity alg, U R U' R'.

For when the corners are adjacently swapped:
Position the two incorrect corners so that they're in the front, then do the PLL parity alg, U', and then a T perm.

Alternatively, if you don't know full PLL, then just do the PLL parity alg whenever you have parity with the corners and solve PLL from there.

Alternatively, for opposite corners you can do the 1st half of Y perm (until you get the T case OLL) then U, PLL parity alg, U' and now just finish Y perm. @TDM recommended this some days ago and it is less moves.

Sent from my Nexus 4 with Tapatalk

 

[Drad]

Can someone explain solving 4x4 with centers first when you build them how do you not mess-up other sides and how do you solve the rest or link me to a decent tutorial.

 

[One Wheel]

Can someone explain solving 4x4 with centers first when you build them how do you not mess-up other sides and how do you solve the rest or link me to a decent tutorial.

Basically you make bars, and then match the bars together. You should be able to just slice the first center together, then slice to bring the piece or bar that needs to be replaced in the center you're solving into an unsolved center and rotate that face to replace the correct piece into that slot, then slice back. Once you finish solving 5 centers, the sixth one must be solved. Does that make any sense? For reduction pairing you pick an axis and slice to pair up pieces, then replace the paired pieces with unpaired pieces, and either pair up the unpaired pieces or re-solve the centers (ideally both at the same time). To replace the paired edges you need to use some variant of F R' F' R or R U R' so that you don't mess up the orientation of the centers. If the unpaired edge is in the right place but upside down use both of those algorithms: R U R' F R' F' R. Once everything's paired solve it like a 3x3, except you will run into parity sooner or later.

I have a totally unrelated question: From the solve videos I've seen it seems that especially for big cubes really fast cubers prefer white plastic. Is this my imagination? Is there a reason for it? I have a crazy theory as to why it might be the case, but I'd be curious if anybody knows, and if my crazy theory might actually be true.

 

[Dene]

Nope, not true, just crazy.

 

[Drad]

I'm trying to learn 4x4 i get weird cases i don't know how do i fix it http://tinypic.com/r/5wi5x0/9

 

[One Wheel]

I'm trying to learn 4x4 i get weird cases i don't know how do i fix it http://tinypic.com/r/5wi5x0/9

Looks like you haven't finished edge pairing. Edge pairing generally needs to be finished before you start 3x3 stage. There are methods for fixing just the last layer in a case like that, but I don't know them. K4, maybe?

 

[Drad]

Looks like you haven't finished edge pairing. Edge pairing generally needs to be finished before you start 3x3 stage. There are methods for fixing just the last layer in a case like that, but I don't know them. K4, maybe?

I have my edge pairing done thats 3x3 stage

 

[One Wheel]

I have my edge pairing done thats 3x3 stage

Edge pairing means all 12 edges are paired, and in the picture you linked to at least two edges are not paired. I can't tell for sure what the other stickers are, but it looks like 3 or 4 edges aren't paired. You clearly have 8 edges paired, but some or all of your yellow edges are not paired.

 

[Drad]

Edge pairing means all 12 edges are paired, and in the picture you linked to at least two edges are not paired. I can't tell for sure what the other stickers are, but it looks like 3 or 4 edges aren't paired. You clearly have 8 edges paired, but some or all of your yellow edges are not paired.

Could you tell me how to do last four edges or send me a good yt vid about it

 

[One Wheel]

Could you tell me how to do last four edges or send me a good yt vid about it

I'm sure you can search for a good video, but basically you just need to be a little creative with slicing, flipping, and slicing back. You can flip the FR edge with R U R' F R' F' R.

 

[One Wheel]

i can't seem to find a good tutorial if you could send me the link to the one you used it would be much appreciated

I don't think I used a video tutorial for learning reduction. I looked up algs instead. Assuming that you can solve a 3x3, the additional algs that you need to know for 4x4 are:

Edge flip: R U R' F R' F' R flips the FR edge

OLL parity: Lw' U2 x (rotate cube so F becomes U) Lw' U2 Lw' U2 Lw U2 Rw' U2 Lw U2 Lw' U2 Lw U2 Lw when you finish f2l and there are 1 or 3 edge pairs oriented correctly in the last layer.

PLL parity: l2 (inner slice move. r or l doesn't matter, just do the same one for the whole alg) U2 l2 Uw2 l2 Uw2. Recognizing PLL parity can be a little tricky. If you have the last layer oriented correctly, the rules are:

No bars: either there are headlights all around, or no headlights, not both.
Bars and single pieces (not sure what term to use there): bars cannot touch, and cannot be diagonal from each other. 2 bars when there are single corners or edge pairs that do not match up with edges or corners of their own color are either
A. On adjacent sides with a single corner between them (Y-perm)
B. Directly across from each other (T-perm)

I think that covers all cases. If you run into something that doesn't follow those rules, do the PLL parity alg and you should end up with something that follows those rules.

Once I figured out reduction I learned Yau from these videos:

 

[Drad]

I don't think I used a video tutorial for learning reduction. I looked up algs instead. Assuming that you can solve a 3x3, the additional algs that you need to know for 4x4 are:

Edge flip: R U R' F R' F' R flips the FR edge

OLL parity: Lw' U2 x (rotate cube so F becomes U) Lw' U2 Lw' U2 Lw U2 Rw' U2 Lw U2 Lw' U2 Lw U2 Lw when you finish f2l and there are 1 or 3 edge pairs oriented correctly in the last layer.

PLL parity: l2 (inner slice move. r or l doesn't matter, just do the same one for the whole alg) U2 l2 Uw2 l2 Uw2. Recognizing PLL parity can be a little tricky. If you have the last layer oriented correctly, the rules are:

No bars: either there are headlights all around, or no headlights, not both.
Bars and single pieces (not sure what term to use there): bars cannot touch, and cannot be diagonal from each other. 2 bars when there are single corners or edge pairs that do not match up with edges or corners of their own color are either
A. On adjacent sides with a single corner between them (Y-perm)
B. Directly across from each other (T-perm)

I think that covers all cases. If you run into something that doesn't follow those rules, do the PLL parity alg and you should end up with something that follows those rules.

Once I figured out reduction I learned Yau from these videos:

ty I did my first 4x4 solve just now

 

[One Wheel]

ty I did my first 4x4 solve just now

Congrats! The first of many I'm sure. 4x4 is my favorite puzzle, although 5x5 and 6x6 have an opportunity to overtake it in the future.

 

[Lykos]

Reasonable goal for 4x4 for the year.

I like setting goals for speedcubing. For the 3x3, I want to be able to do a sub-20 avg100 until the end of the year. Currently I am at 24-30.

What would be a reasonable goal for the 4x4? Currently I am at 2:15 to 2:30, but I really have no idea what would be a reachable, but slightly ambitious goal. I don't intent to practice 4x4 as much as 3x3, but a tiny bit of ambition is always good.

Sent from my Nexus 6P using Tapatalk

 

[supercavitation]

Reasonable goal for 4x4 for the year.

I like setting goals for speedcubing. For the 3x3, I want to be able to do a sub-20 avg100 until the end of the year. Currently I am at 24-30.

What would be a reasonable goal for the 4x4? Currently I am at 2:15 to 2:30, but I really have no idea what would be a reachable, but slightly ambitious goal. I don't intent to practice 4x4 as much as 3x3, but a tiny bit of ambition is always good.

I averaged about 1:05 at sub-20, though I practice 4x4 a lot more than I practice 3x3. If you'd rather practice 3x3 more, maybe aim for 1:15-1:20?