Fixing Mirror Cube Centers

SilentSolver

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Oct 27, 2013
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Greetings all! If there is already a thread discussing this I apologize, when I searched all I found were questions about purchasing and popping pieces and what not, so here it goes; I own the ShengShou Mirror Blocks, and the stickers are designed to imitate brushed metal, with striations running side to side (or up and down), and upon solving sometimes the grooves do not line up properly, so the cube is solved but the way the light reflects off of the the centers makes it obvious they are not oriented correctly. Superficial I know but I think it makes the solve look slightly more impressive and 'clean'. I have watched a few videos and only one has really discussed this issue and I learned a couple of algorithms to turn them 90 degrees when they are directly across from each other (M2 U M2 U')x3 or one on the front face and the other on the top face (M' U M U')x5, but I have run into scenarios several times where three are incorrect, and when I use the algorithms I can correct two of them, but I am almost always left with just one out of place. I wanted to find out if there is something I need to keep in mind to either avoid this altogether, or if there is an algorithm(s) that can fix it? I hope I have given a concise explanation of my problem and that you fine people can help me. Thanks!
 
You can either turn (only) one center with 180 degrees or turn (only) two centers with 90 degrees, and the combination of those (e.g., turning 4 centers with 90 degrees).

Here is an algorithm for turning the U center with 180 degrees and leaves everything else:
(U R L U2 R' L')2

Turning just one center with 90 degrees is impossible. If you want to do that, search another center which you can turn with 90 degrees with it.
 
Renslay posted a good alg for when there is 1 center twisted 180 degrees.

When 2 centers have to rotate 90 degrees, use a commutator:

For 2 adjacent centers:
U (M E M') U' (M E' M')

For 2 opposite centers:
U (M E2 M') U' (M E2' M')
 
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Joël's turning two faces thing is a commutator so it can also be tweaked to turn two centers 180.

U2 (M E M') U2 (M E' M') = 180 two adjacent centers (U and L centers)

U2 (M E2 M') U2 (M E2 M') = 180 two opposite centers (U and D centers)

Not that turning an mirror cube center 180 does much I just enjoy this variation on the commutator for picture cubes and whatnot.
 
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Thank you all for the help, and forgive me if I'm a bit dense at first, I'm still fairly new to twisty puzzles, but wouldn't rotating one center 180 degrees be redundant and solve nothing? Because if a center is 90 degrees out of alignment, then rotating it 180 degrees is a perpetual half-circle that constantly un-solves it. So as I see it now, it is impossible to correct one solitary center when all others are solved? Now if two centers are not oriented correctly, then the algs I have and these new ones you gave me to correct them will obviously work, but I think having three unsolved simultaneously will just have to be avoided by orientation at the beginning of the solve. Please correct me if I'm wrong, I guess I just don't see what you see yet.
 
On a brushed metal mirror cube rotating a center 180 does effectively nothing. Rotating a single center (or as I chimed in two centers) 180 is a very handy alg for a picture cube where a picture or pattern is on each side and having a center out of alignment makes the picture wrong.

If you really have only one center out of alignment perhaps the cap for that center was put on wrong. As long as it's not the top (thinnest layer) of you mirror cube try to pry off the center cap and pop that on right. If the out of alignment center is the top most thin layer pry a different center cap off, assemble it 90 degrees out of whack and apply some of the algs. The thinest layer center in many mirror cubes does not have a cap but is a solid piece riveted on so trying to pop it could break the puzzle.

You will not get 3 centers or your case 1 center 90 degrees out of whack on a properly assembled cube. The total center twists possible on a solved 3x3 is always an even number of 90 degree turns. So a 180 is possible on one center but not a single 90 like you have. Three centers 90 degrees out of whack is another situation that shouldn't happen on a properly assembled cube.
 
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On a brushed metal mirror cube rotating a center 180 does effectively nothing.
If you really have only one center out of alignment perhaps the cap for that center was put on wrong.

Precisely, thanks. I was beginning to suspect that to be the case as it happened more often then not. I feel a little stupid for not giving it more thought sooner but live and learn. Aside from that I did learn a few new algorithms so I would say mission accomplished. Thanks again guys I really appreciate it. I'm sure I will have many more questions on my journey of cubing and I'll make sure to come to these forums. Started cubing a little over a month ago and got myself to about a 1:30 AO 5 in about two weeks then started learning some new techniques to get faster so my goal is to get to sub-60 secs, more precisely around 0:45. Thank you all again, you guys are awesome!
 
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