• Welcome to SpeedSolving.com — the world’s largest puzzle community!

    You’re currently browsing as a guest, which means you have limited access to discussions, resources, member profiles, and community features.

    Join 50,000+ cubers and puzzle enthusiasts from around the world to ask questions, share solves, improve faster, and be part of the community.

    Registration is free, fast, and easy — create your account today.

    Already a member? Log in here to hide this message and start participating.

One-Answer 4x4 Question Thread

I can see that people have asked about solving a 4x4x4 by reducing it to a 2x2x2 in this thread, but I did not see any example solves. I also searched the entire (which isn't that long, of course) The 4x4x4 example solve game thread, and I didn't see any such solves there either.

Are there any move-efficient 2x2x2 reduction 4x4x4 solves (typed up) online? I've seen videos like this where someone does it, but I'd rather know how many moves the best of us have achieved with this approach. (Where the amount of time taken doesn't matter.)
 
I can see that people have asked about solving a 4x4x4 by reducing it to a 2x2x2 in this thread, but I did not see any example solves. I also searched the entire (which isn't that long, of course) The 4x4x4 example solve game thread, and I didn't see any such solves there either.

Are there any move-efficient 2x2x2 reduction 4x4x4 solves (typed up) online? I've seen videos like this where someone does it, but I'd rather know how many moves the best of us have achieved with this approach. (Where the amount of time taken doesn't matter.)

J Perm made a video on it
 
I can see that people have asked about solving a 4x4x4 by reducing it to a 2x2x2 in this thread, but I did not see any example solves. I also searched the entire (which isn't that long, of course) The 4x4x4 example solve game thread, and I didn't see any such solves there either.

Are there any move-efficient 2x2x2 reduction 4x4x4 solves (typed up) online? I've seen videos like this where someone does it, but I'd rather know how many moves the best of us have achieved with this approach. (Where the amount of time taken doesn't matter.)
I think that if you know some sort of wing, center, and corner commutator (one of each) then it shouldn’t be too hard. It might not be very move-efficient, though. I haven’t tried it myself.
 
I can see that people have asked about solving a 4x4x4 by reducing it to a 2x2x2 in this thread, but I did not see any example solves. I also searched the entire (which isn't that long, of course) The 4x4x4 example solve game thread, and I didn't see any such solves there either.

Are there any move-efficient 2x2x2 reduction 4x4x4 solves (typed up) online? I've seen videos like this where someone does it, but I'd rather know how many moves the best of us have achieved with this approach. (Where the amount of time taken doesn't matter.)
I'll give this a try; check the example solve thread in a couple of hours. On a handscramble, I managed to get to five grouped corners in around 90 moves, which is already much more than what I need to do reduction+cross, then I got hit with the accursed parity. (Now that I think about it, domino J/T perm should work to solve it. Hmm.)

Thinking out loud: unlike in a normal reduction solve, where the order in which you pair the edges doesn't matter, here, there is freedom to choose which centre pieces to use for which corner blocks, so the order matters! (Probably not a lot, but still.) The ideal seems to be to solve four corner blocks of the same layer first, but if I'm going to do that, why wouldn't I just directly solve two layers (which is way easier, imo) instead of building four corner blocks?

edit: 64 moves to 6 blocks (way better than I expected), but I can't figure out how to do the last two blocks without just spamming commutators.

edit2: Posted a 93-move solution there.
 
Last edited:
So one 4x4 PLL case that I'm running into, but which isn't covered in the CubeSkills beginning tutorials is where everything is solved except two opposite corners need to be swapped. What is the recommended approach to dealing with this?
 
So one 4x4 PLL case that I'm running into, but which isn't covered in the CubeSkills beginning tutorials is where everything is solved except two opposite corners need to be swapped. What is the recommended approach to dealing with this?
adj parity into Y perm would be the easiest and fastest non-algorithmic approach
 
By my count, Nb (17 moves) + parity (6 moves) is two moves shorter than Y perm (17 moves) + parity (6 moves) + a U/U` pair in the middle.
 
By my count, Nb (17 moves) + parity (6 moves) is two moves shorter than Y perm (17 moves) + parity (6 moves) + a U/U` pair in the middle.
Still, Nb perm is complete garbage compared to a Y perm. Drilling both the Y perm with parity in the middle and the Nb followed by parity on my 4x4, I could get the first one sub 3 consistently, but was barely sub 4 on the second one.
 
Well since I don't (yet) know either Y or Nb, I'm not sure I want to confuse myself with learning a variant of Y where I interrupt it mid-execution to insert (U [parity] U'). Using variations on perms you've already mastered in the interests of shaving off a second makes sense to be sure. But as a beginner 4x4 solver who is still barely sub-60 using 4LLL on a 3x3, speed on the 4x4 is not a priority (or even much of a consideration at this point).
 
Well since I don't (yet) know either Y or Nb, I'm not sure I want to confuse myself with learning a variant of Y where I interrupt it mid-execution to insert (U [parity] U'). Using variations on perms you've already mastered in the interests of shaving off a second makes sense to be sure. But as a beginner 4x4 solver who is still barely sub-60 using 4LLL on a 3x3, speed on the 4x4 is not a priority (or even much of a consideration at this point).
You asked why you wouldn't use Nb instead of Y, and we told you.
 
Back
Top