Big Cube BLD Discussion

[Cubenovice]

My noobish perspective:

I solve them Clockwise starting from my buffer piece Ul
I find that Ul buffer gives me nice comms with plenty of r and M moves

For lettering: same scheme as x centers (makes them easy to grasp since you solve them similar to the x centers)

Here’s an example solve including parity that I wrote on the previous page
http://www.speedsolving.com/forum/s...BLD-Discussion&p=766589&viewfull=1#post766589

solving order
x centers - comms
+ centers - comms
Wings – r2
Midges – M2
Corners – Old Pochmann

In case of parity in the M2 / OP part:
Solve M2 edges
Parity fix U' F2 U M2 U' F2 U fixes M slice but swaps UL and UB Midges
Solve Corners Old Pochmann: you are now left with a 2+2 wing swap on UL and UB
parity fix y2 R U R' U' Rw2 F2 U2 r2 U2 F2 Rw2 U R U' R'

y2 R U R' U' - sexy move places the 2+2 wing swap opposite of eachother
Rw2 F2 U2 r2 U2 F2 Rw2 - opposite 2+2 wing swap
U R U' R' – undo sexy

 

[AbstractAlg]

Yes that is the order that I'm doing currently and I do exact same things, so it means no prettier way of dealing with M2 parity? Oh, well. :|

 

[Cubenovice]

Just yesterday I considered doing corners first on a 5BLD attempt (to save on memo time) but when I found 7 corner targets this seemed waaaaaay to complcated.

For 4BLD I have switched to corners first because there the parity and center rotations are still managable.
For 5BLD I will have to study a bit more to determine all the scenarios for corners first.

 

[bobthegiraffemonkey]

For UL UB wing switching on 5x5 I prefer: 4r2' U' r2' U2 F2 2R2 F2 U2 r2 U 4r2', but maybe I'm weird.

 

[AbstractAlg]

Just yesterday I considered doing corners first on a 5BLD attempt (to save on memo time) but when I found 7 corner targets this seemed waaaaaay to complcated.

For 4BLD I have switched to corners first because there the parity and center rotations are still managable.
For 5BLD I will have to study a bit more to determine all the scenarios for corners first.

Use comms.

For UL UB wing switching on 5x5 I prefer: 4r2' U' r2' U2 F2 2R2 F2 U2 r2 U 4r2', but maybe I'm weird.

That is weird, yet helpful.

 

[Ollie]

For UL UB wing switching on 5x5 I prefer: 4r2' U' r2' U2 F2 2R2 F2 U2 r2 U 4r2', but maybe I'm weird.

What's 4r2? :/

 

[vcuber13]

i dont have a cube but i assume turn the 4 rightmost layers 180°, L2 x2 on 5x5

 

[drewsopchak]

What 3cycles of corners aren't center safe? Are R2 U R2 U' R2, D style comms center safe? Sorry, but I don't have a supercube.... shame on me.

 

[bobthegiraffemonkey]

i dont have a cube but i assume turn the 4 rightmost layers 180°, L2 x2 on 5x5

Yes, in SiGN notation assuming I used it correctly.

 

[Renslay]

What 3cycles of corners aren't center safe? Are R2 U R2 U' R2, D style comms center safe? Sorry, but I don't have a supercube.... shame on me.

You don't have to own a supercube. Just count the number of the turns in a side. That algorithm has the following moves, in a different order: R2R2R2R2R2R2, UU'UU', DD'. None of them rotate centers overall.

If I'm not wrong, a PQP'Q' commutator does not affect on centers, because of its structure: every "center-rotating movements" have their inverse. But you can check any algorithm with that method; not just 3-cycles. E.g., The A-perm "B L' B R2 B' L B R2 B2" has this moves: BBB'BB2 L'L R2R2 -> it is also center safe.

But this PLL:
(R U R' U') (R' F) (R2 U') (R' U' R U) (R' F')
has:
RR'R'R2R'RR': no center turning
UU'U'U'U -> It turns the U side center ccw
FF': no center turning

So, if you do this PLL twice, you get back the solved cube, however, you did a 180 degree turn on the U face (and only the U face).

Note that if your algorithm has M (or similar slice move), you have to be careful with the counting, which movement turns which center. I think you can figure it out yourself from here.

 

[drewsopchak]

You don't have to own a supercube. Just count the number of the turns in a side.
FF': no center turning

Yes, but I spontaneously generate comms for big cubes. I suppose all opt to use pure BH and A-perm conjugates.

 

[Renslay]

As I mentioned, I think a commutator (because of its PQP'Q' structure) does not rotate any centers overall.

 

[Ollie]

Yes, but I spontaneously generate comms for big cubes. I suppose all opt to use pure BH and A-perm conjugates.

Commutators are centre safe, inc other pieces like wings, midges and centres. BH is mostly commutators and A9s which are based around comms (I think they include set-ups to a commutator and cancellations to make 9 moves) so you'll be safe with that.

Old Pochmann corners is NOT safe.

 

[vcuber13]

what about [M E M', U]?

 

[qqwref]

Comms are not necessarily center-safe. [M,U2] is the most obvious example.

 

[JasonK]

Am I wrong in saying that all corner comms are centre-safe? Because that's what was originally asked about.

 

[AbstractAlg]

All corner commutators are center safe.

 

[TMOY]

But you can check any algorithm with that method; not just 3-cycles. E.g., The A-perm "B L' B R2 B' L B R2 B2" m here.

SInce when has the A-perm ceased to be a 3-cycle ?

And yes, every comm using only outer layer turns is center-safe. This includes the corner comms, but not [M,U2] or things like this. (But [M,U2]^2 happens to be center-safe. This is useful for midges: when a 3-cycle can be solved by a [M,U2]-like comm, just do it twice in the opposite direction.)

 

[DrKorbin]

Wings: DFr > RFd > FRu.
Could anyone share a nice alg for this case, please?

 

[TMOY]

Uw' x' R2 U' r' U R2 U' r U x Uw