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Big Cube BLD Discussion

Mike Hughey

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Whenever I hit my buffer face with the second piece in a pair, I just keep going as if I didn't. So I would have done Ubl (which is my starting buffer piece) -> Lub -> Ubr, and then keep going with Ubl as my buffer for the next pair, using the piece that's at Ubr.

If I hit my buffer piece with the first piece in the next pair, I just stop there and start with the new piece as my buffer piece. So I use floating buffers - I move them each time I hit this. I like this because it means I have 1/2 commutator less to do each time this happens. (Of course, it's only really a savings with an even number of them - I have to get 2 cases like this to save a commutator.) But as a result, on a typical 4x4x4 BLD, I seem to average somewhere between 1 and 2 commutators saved. And the way I memorize, it really doesn't cost me anything on memorization. I've tried to convince Chris this is a good way to go, but I can't seem to convince him - I guess with his memory technique, it's not as clearly a win.
 

dbeyer

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Choosing an orientation with less U centers solved would actually heighten the chances of commutators saved (as long as you can find an orientation that solves an equal amount as a dominate U layer orienation). You would have to solve more U centers. Which each U layer center, not permuted has an equal chance of being the middle or the end piece in a cycle.
Such that;
[Buffer -> Middle -> End].
You also still chance that the very last cycle is a 2-swap (But solved in 3-cycles).

Oh guys, check this thought out.
Centers, I know you all probably use U layer centers to for your buffer reference.

Check out this thought.
Perhaps B/F face buffers?
Pros--
Insertions on the L/R face. Such as u'[R]u to insert the R sticker to the Fru.
Toss up cases on the U layer. such as rU2r' to insert the U sticker to the Fru.
Easy interchanging on the u/r slices.
those fast 11 move cases can just be rotated with x to set the Fru to the Urb.
On 4x4 here is a few fast cases.
r' (3F)'l(3F) r (3F)'l'(3F)
u (3L)d'(3L)' u' (3L)d(3L)'

Anyway ...
Later,
DB
 

Jude

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Ok, I have a question about 4x4x4 centre commutators, I hope this is the right place to ask it.

I just solve 2 at a time doing 3 cycles, starting with the buffer Ubl.

My question is, what do I do if my first cycle goes something like Ubl --> Lub --> Ubl? Normally what I do is I make it Ubl --> Lub --> Uxy where Uxy is a piece that is already correct on the U face. For the first time ever today however, I had a scramble where the best place to hold it had 0 correct centres on the U face, so I wasn't sure what to do. In the end I did Ubr (which was a piece of the same colour as Ubl) --> Lub --> Ubl and then started my next cycle with the buffer piece Ubr. However, at the end of the solve I was just 2 centres off (one of which was Ubl) so I thought what I did might not work.

Hope I made that clear, thanks.

You can either start with the next piece over (like Ubr) as your buffer, and then use a three cycle at the end (your U-layer centers will be done at that point). Or you could not change buffers and do a cycle

Ubl --> Lub -->(some random center that needs to be solved).

That's breaking into a new cycle. You just have to remember to close off the cycle at the end with the same (some random center) you started with. You may have to do this more than once:

Ubl --> Lub --> (random center 1)
...
Ubl --> (random center 1 ) --> (random center 2)
...
Ubl --> (blah) --> (random center 2)

Or you may end up with

...
Ubl --> (random center)

at the very end. But if it's at the very end, all the other U face centers will be solved at that point, so you can just use one of those in your last cycle.

That make sense?

Whenever I hit my buffer face with the second piece in a pair, I just keep going as if I didn't. So I would have done Ubl (which is my starting buffer piece) -> Lub -> Ubr, and then keep going with Ubl as my buffer for the next pair, using the piece that's at Ubr.

If I hit my buffer piece with the first piece in the next pair, I just stop there and start with the new piece as my buffer piece. So I use floating buffers - I move them each time I hit this. I like this because it means I have 1/2 commutator less to do each time this happens. (Of course, it's only really a savings with an even number of them - I have to get 2 cases like this to save a commutator.) But as a result, on a typical 4x4x4 BLD, I seem to average somewhere between 1 and 2 commutators saved. And the way I memorize, it really doesn't cost me anything on memorization. I've tried to convince Chris this is a good way to go, but I can't seem to convince him - I guess with his memory technique, it's not as clearly a win.


Ah, thanks very much guys. So (assuming white is on top), if the first white piece we find is only the 2nd in a cycle, we don't put it into Ubl but actually Ubr, then just continue until our cycle is done. Then, when we start the next cycle instead of starting from Ubr as I normally start my 2nd cycle, I start from Ufr (where I start my 3rd). I think as I typed that out it came out wrong and I may have over complicated it, but I understood what you two have said.
 

Mike Hughey

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Oh guys, check this thought out.
Centers, I know you all probably use U layer centers to for your buffer reference.
Yes, I certainly do.

Check out this thought.
Perhaps B/F face buffers?
Pros--
Insertions on the L/R face. Such as u'[R]u to insert the R sticker to the Fru.
Toss up cases on the U layer. such as rU2r' to insert the U sticker to the Fru.
Easy interchanging on the u/r slices.
those fast 11 move cases can just be rotated with x to set the Fru to the Urb.
On 4x4 here is a few fast cases.
r' (3F)'l(3F) r (3F)'l'(3F)
u (3L)d'(3L)' u' (3L)d(3L)'
Cool idea. Not sure I have the energy to research it immediately, but it is a cool idea! Actually, the thing that was most motivating me on that idea earlier was 6x6x6 BLD. I have the mod with the glued pieces, but without the pins, so I have the problem with the center coming out of alignment. The way my cube is rigged, and the way I hold my cube, that means the slice turn around the F/B axis is the one that can get out of alignment. (Which incidentally means I'm always kind of cheating on 6x6x6 BLD - once my inner centers are solved, I can immediately tell whether or not my cube is properly oriented by which slice comes out of alignment. :)) So if I can choose pieces such that I minimize inner f/b slice turns, I win big.
 

peterbat

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Ubl --> (blah) --> (random center 2)
Huh?

Right. But if blah is already solved, shoot to waffle=ijm.

EDIT:

Mike Hughey said:
Whenever I hit my buffer face with the second piece in a pair, I just keep going as if I didn't. So I would have done Ubl (which is my starting buffer piece) -> Lub -> Ubr, and then keep going with Ubl as my buffer for the next pair, using the piece that's at Ubr.

That's what I do too -- I don't know why I just started to describe breaking into a new cycle (which I only do once all the U layer centers are solved). So when all my U layer centers are solved, I start a new cycle somewhere else. Suppose Lfu is unsolved, and has to go to Dbr. I would then *still* use Ubl as my buffer, and perform the commutator Ubl --> Lfu --> Dbr, even though Ubl is already solved. This isn't as efficient as what Mike does (he would just use Lfu as his buffer, if I'm understanding him correctly), but it's marginally more brainless, and I take brainless whenever I can get it (for now at least) :)
 
Last edited:

Sakarie

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Why do you want to change buffer all the time? So when you gets to shoot to another place in your bufferside, let's say the U-face, you might save 1 letter/image for every time, which means that you might save 4 letters. But that's only if they're are the first in a cycle, which means that you in average saves 2 letters/images, saving one commutator.

The cons are that
1. You still have to memorize that you chang buffer, which means that there's still som memorizing to do.

2. You have to learn how to do commutators from all of the U-face centers. It might not be hard, but I would think there's more to gain if you know the commutators from one center very fast, instead of saving very little (in my eyes), for knowing them from everywhere?

I do not use this tecnique myself, so there might be some misunderstanding and misthoughts from my side. Just to make sure, this is no accusation at the method, it's just a question, since I don't understand.
 

Mike Hughey

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It's a good question, and those two reasons are the reasons Chris doesn't do it. (Mainly the first reason.)

But for me:
1. The extra memorization isn't extra at all. I already "waste" a person at each location which tells which buffer it is, and I find that that takes almost zero time to memorize.
2. Since I don't do BH for centers, but instead do intuitive commutators with setup moves, and I've practiced moving buffers for so long, I find that they're just as fast to do from any buffer.

So I guess it needs to be like it is for me in order to pay off any. But I like it.
 

Pitzu

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I was interested in making a statistics like this:
Rubik's Cube: Blindfolded until 2005 All Persons
http://www.worldcubeassociation.org...ars=until+2005&show=All+Persons&single=Single
32 persons

Rubik's Cube: Blindfolded until 2006 All Persons
http://www.worldcubeassociation.org...ars=until+2006&show=All+Persons&single=Single
91 persons

4x4 Cube: Blindfolded until (almost;))2009 All Persons
http://www.worldcubeassociation.org...ars=until+2009&show=All+Persons&single=Single
38 persons

4x4 Cube: Blindfolded until 2010 All Persons
What do you think?
 

MatsBergsten

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I was interested in making a statistics like this:
Rubik's Cube: Blindfolded until 2005 All Persons
32 persons
Rubik's Cube: Blindfolded until 2006 All Persons
91 persons
4x4 Cube: Blindfolded until (almost;))2009 All Persons
38 persons
4x4 Cube: Blindfolded until 2010 All Persons
What do you think?

Do you want to guess / estimate the number of persons that will have solved
the 4x4 BLD after 2010? And do you want my guess or do you want a comment
on whether it is possible to use the statistics from 3x3 BLD as an estimator?

My guess is 50.
My opinion is that the 3x3 statistics does not help much. If you want to use it,
why not take the growth from 2008 to 2009 then?
 

MatsBergsten

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Now, solving the 3 cycles. Its very intuitive, and can be solved using 4 moves, and no cube rotations. We are going to use M and E turns, to solve these other 8 cases.

I have now tried to understand and use this (once in the Forum comp and failed :()

But what I fail to find in your explanations are the cases with parity. To rotate three centres and double along M2/E2/S2 is easy (that is change orientation within the subgroups (?) with/without parity). But how do you swap from a parity case to one without parity during orientation.
 

Sakarie

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Now, solving the 3 cycles. Its very intuitive, and can be solved using 4 moves, and no cube rotations. We are going to use M and E turns, to solve these other 8 cases.

I have now tried to understand and use this (once in the Forum comp and failed :()

But what I fail to find in your explanations are the cases with parity. To rotate three centres and double along M2/E2/S2 is easy (that is change orientation within the subgroups (?) with/without parity). But how do you swap from a parity case to one without parity during orientation.


Why all this talk about orientation? You're not supposed to orient the centers?

To answer what I think is your actual question, I think you just have to apply an algorithm. If you have "centers/corner/middle-edges-parity" (since it's actually the same thing, just variants of on another) you have to not solve the centers, and afterwards apply an algorithm changing the pieces you want to. Changing a fourcycle of centers and two corners ain't that hard, and can be done with the algorithm trying-to-speedcube mentioned Uw Fw' Bw Lw Fw Bw' Uw2 Rw2 Dw Rw Lw' Fw' Rw2.
 

kinch2002

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I'm new to big cube BLD and solved a 4x4x4BLD for the first time yesterday (yay!). Currently I make up phrases using letters for centres and I find that really easy. For edges I've been memorizing number sequences - this takes quite a while (as the numbers go up to 24!), and although it's not a problem for me to recall the numbers it takes far longer than memorizing my centres. I'm worried that if I try doing letters for edges as well I'll start mixing up centes and edges when I recall. Has anyone got any tips for not confusing centre and edge memos whilst using the same memo method for both?
 

MatsBergsten

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I'm new to big cube BLD and solved a 4x4x4BLD for the first time yesterday (yay!). Currently I make up phrases using letters for centres and I find that really easy. For edges I've been memorizing number sequences - this takes quite a while (as the numbers go up to 24!), and although it's not a problem for me to recall the numbers it takes far longer than memorizing my centres. I'm worried that if I try doing letters for edges as well I'll start mixing up centes and edges when I recall. Has anyone got any tips for not confusing centre and edge memos whilst using the same memo method for both?

First: congratulations!
Secondly, I use exactly the scheme with letters for cubies and make silly sentences
on the fly. I also use the same set for both centres and edges (and corners on Multi).
I have not mixed them up, you probably have a little visual help to keep them apart
(at least I have). For 5x5 I use two sets (men / women) for the different types of centres.
Only when I tried 6x6 BLD and 7x7 BLD did it start to get confusing (a little).
 

kinch2002

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Thanks Mats, I'll assign letters to my edges as well and try that system tomorrow. I've had 33 and 26 mins as my two solves but hopefully I'm getting much quicker at setting up/doing commutators every time. I had a think about 5x5x5BLD today and most of it seems pretty similar to 4x4x4BLD so I might even try that in the next few days.
 

joelwong

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how to memo 4x4 edges

since there are two edges, i do not understand how the youtube guy memos the edges. Let us say i hold the cube with green top yellow front the piece in the buffer is red of red green. how do i know which one needs to be solved after it??

help please
 
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Your buffer is DFr, right?

In your head do 2 possible ways to put that piece in its spot; in this case you could do F' R, or you could do D R2. D R2 puts the piece in URf with red on top and green on the right, which isn't what you want. So the correct move would be F' R, which puts the piece in URb with green on top and red on the right. So the piece has to go to URb.
 

LarsN

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memo/execution sequence

Due to a lot of dnf's lately I started thinking about the sequence of which I do memo/execution. At the moment I do it in this order:

Memo:
wingedges
x centers
+ centers
middle edges
corners
(middle centers)

Execution:
(middle centers)
Corners
Middle edges
+ centers
x centers
wingedges
(corner/edge parity)

It happens a lot that I forget part of the memo for wing edges or that I get some huge memo pausing with them. This has caused at least half of my dnf'ing lately.

How are your thoughts on the sequence of memo/execution? Would it be better to execute in the same order as memo?
 

Mike Hughey

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I've always liked going in reverse order, as you do. My order for 5x5x5 BLD is:

Memo:
choose orientation and memorize it (middle centers)
central edges
+ centers
wings
X centers
corners

Execution:
corners
(middle centers)
X centers
wings
+ centers
edge parity
central edges
corner parity

It's a little funny, I guess. I do middle centers after corners because I memorize an image for my middle centers, and it sticks pretty well, while the corners are something I want to have be purely short-term memory, so I don't want anything between memorizing and executing them. I should probably execute + centers before wings, but I've gotten used to this and I haven't bothered to change. With 7x7x7 BLD, I always do all the centers first and then the wings, so I can do edge parity right away after doing the wings (so I don't have to remember to do it later). I might try that on my next 5x5x5 BLD solve - it shouldn't be that hard to switch.
 
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