Big Cube BLD Discussion

[Goosly]

My question is this: are centres (typically 16-18 targets) too much information for fast, short term audio memo? Should I just keep practising, or am I on the wrong path using audio for this?

IMO, it's too much. But I'm a noob in BLD, so my opinion doesn't really matter

 

[mark49152]

IMO, it's too much. But I'm a noob in BLD, so my opinion doesn't really matter

Yeah I'm wondering if any BigBLD ninjas have tried it and what their experience is.

 

[mark49152]

At Exeter Open 2016, I struggled so badly with the second 4BLD scramble that I threw the solve away. However, everyone else who had a success got it on that scramble! So I reconstructed to see why I found it so difficult.

B R2 U2 F U2 F L2 D2 F D B' D' F' D' R2 D L R' F' D2 Fw2 R' Uw2 D Rw2 Uw2 R' L2 D Fw2 B2 U L' Fw' L F' D U F' Uw' Fw L2 Uw Rw2 U' R2 z' y'

Using the orientation I chose in comp (three yellows on top, white at Ubr) I couldn't do it at home either. I had to write down the wing memo to find my mistake. It was 28 targets, 5 breaks. Awful. So I tried it with the white at Ufr. Wing memo was now easy - 24 with 1 break. (I guessed that's the orientation the others would most likely have chosen as it gave more solved centres overall; I had traded two side centres for not having to solve any U-face centres ).

That taught me something I didn't realize about 4BLD. Because centres are not fixed, wing and corner cycles depend on orientation, unlike 3BLD. (It should have been obvious to me because there are simple examples, like two wings swapped in place no longer being an isolated 2-cycle if you change the orientation.)

So now I am curious whether any experienced 4BLDers use this in choosing an orientation? I have always looked at centres only, but it seems just as valid to take into account solved wings or corners, corner twists, or even avoiding obvious 2-cycles on wings or corners.

And a related question - can orientation affect wing or corner parity? My thinking is no, because a quarter rotation would be equivalent to two quarter moves on opposite faces... but I might be wrong.

 

[Goosly]

So now I am curious whether any experienced 4BLDers use this in choosing an orientation? I have always looked at centres only, but it seems just as valid to take into account solved wings or corners, corner twists, or even avoiding obvious 2-cycles on wings or corners.

Only looking at centers is, on average, the best way to get an overall faster memo time because re-orienting to get an 'easy' memo is part of memo.
If you also look at wings/corners, you'll just loose more time than you gain, on average.

 

[Jacck]

And a related question - can orientation affect wing or corner parity? My thinking is no, because a quarter rotation would be equivalent to two quarter moves on opposite faces... but I might be wrong.

Corner parity: yes! Take a scrambled 4x4 and count the corners to be solved, then make a "y" and try it again. You will see, that one is with parity and the other not. But checking the corners-parity first isn't faster than solving the parity. Except: if you have an annoying scramble and you have only found two not at all good ways to hold it in a too long time, you may check for the parity to feel better
Edit (after bobthegiraffemonkey's explanation): the previous text is nonsense, I don't know, how I got to this (and how I checked it on my 4x4). I think - like the wing parity - corner parity is only depending on the number of 90°-face-turns in the scramble.

Wing parity: in my opinion, no. I'm pretty sure, you have wing parity, when there is an odd number of 90°-innerslice-moves in the scramble.

 

[bobthegiraffemonkey]

And a related question - can orientation affect wing or corner parity? My thinking is no, because a quarter rotation would be equivalent to two quarter moves on opposite faces... but I might be wrong.

Yup, you're right, you just need to count the number of 4-cycles in a rotation such as y. Corners: two 4-cycles, wings: six 4-cycles, both are even so neither have an effect on parity. By induction no rotation will have an effect on parity.

 

[Hari]

I was going through Ollie's list for big BLD algs and found many X- centers algs like this: [r' U r U', l2]. This is for BU. And [2Lw: [r2, U' l' U]] for BV. Why not the simpler 8 movers for these cases? I could give more examples for BT,BJ,etc. Am I missing out on something? And same question for +centers. Isn't Ul-Ub-Bd easier as [x'; [M', U' l' U] ] rather than y rotation to an 8 mover?

 

[tseitsei]

I was going through Ollie's list for big BLD algs and found many X- centers algs like this: [r' U r U', l2]. This is for BU. And for BV. Why not the simpler 8 movers for these cases? I could give more examples for BT,BJ,etc. Am I missing out on something? And same question for +centers. Isn't Ul-Ub-Bd easier as [x'; [M', U' l' U] ] rather than y rotation to an 8 mover?

[r' U r U', l2]
This is what I do. Mostly because all the 8-movers I can find are simply slower to execute. If you have a good one please share

[2Lw: [r2, U' l' U]]
Not sure about this... probably he finds it faster to execute because less inner layer turns but I would just do [r2, U' l U]

for + centers I have a different buffer so I dunno.

 

[Shiv3r]

Hey guys for even puzzles like the 4x4 and 6x6, edges(after pairing) can be solved without disturbing any other pieces, which means less algs than Old pochmann for 3x3. I think that for 4x4 that will be the method I use for BLD.

 

[Cale S]

Hey guys for even puzzles like the 4x4 and 6x6, edges(after pairing) can be solved without disturbing any other pieces, which means less algs than Old pochmann for 3x3. I think that for 4x4 that will be the method I use for BLD.

I don't understand what you mean

 

[Shiv3r]

for a 4x4 you can swap the edge pairs across one face like a T-permutation but without swapping the corners, am I right?

 

[qaz]

for a 4x4 you can swap the edge pairs across one face like a T-permutation but without swapping the corners, am I right?

Correct, but BLD solvers don't pair up edges before putting them in the correct place so this would have limited usefulness.

 

[Shiv3r]

huh.
so what would the old-pochmann style algorithms look like? a t-perm with only one of the two slices?

 

[qaz]

huh.
so what would the old-pochmann style algorithms look like? a t-perm with only one of the two slices?

You could use something like l' U2 l' U2 F2 l' F2 r U2 r' U2 l2 to swap 2 wedges at a time I suppose

 

[Shiv3r]

also, the r2 method's only online explanation is on eriks website, which has been down since I started cubing. so what is the Idea of ir?

 

[qaz]

also, the r2 method's only online explanation is on eriks website, which has been down since I started cubing. so what is the Idea of ir?

Do you know M2?

 

[Shiv3r]

yes. very. and Im also very dissatisfied with all BLd corners methods out there, none are easy to remember (even OP), so I use Boomerang method for corners.

 

[qaz]

yes. very. and Im also very dissatisfied with all BLd corners methods out there, none are easy to remember (even OP), so I use Boomerang method for corners.

r2 is essentially M2 except only using one slice. It's a bit more difficult since each wedge has a unique letter instead of two letters, one for each orientation, as M2 has, but it's the same concept.

 

[Shiv3r]

and what about the centers? would I just use the same Idea as cage methods?

 

[h2f]

and what about the centers? would I just use the same Idea as cage methods?

The method called U2. Very easy. Only 3 algs needed to know for centers on D and U.