# 7x7 centers by reduction



## Stefan (Jul 2, 2008)

An idea to solve the 7x7 centers: Reduce to 5x5 centers.

Step 1) Build 3x3 centers on all sides like you would on a 5x5.
Step 2) Build "center tredges" like you'd build tredges on a 5x5.
Step 3) Solve centers like 5x5 centers.

Hope that's clear, and hope this hasn't been mentioned before. Well, I think it's good and I don't hear Per cursing, so that might be a good sign.

Edit to make it clearer: Steps 1+2 make the centers of each side look like this:


```
ABBBC
DEEEF
DEEEF
DEEEF
GHHHI
```

Step 1 builds the E square, step 2 builds the B/D/H/F triples.


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## masterofthebass (Jul 2, 2008)

This is almost impossible. Have you tried this? The only way to get the outer "tredges" is to use commutators, which isn't very fast.


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## Mike Hughey (Jul 2, 2008)

Have you tried it? How fast were you able to do it?

I'm just awful at 7x7x7 centers (it looks like others have the same problem), so anything like this that might help would be welcome. I'm going to go home and try it tonight for sure.

My current approximate splits (for the 2 solves I've tried so far since solving it BLD):
First 4 centers: 11 minutes
Last 2 centers: 4 minutes
Edge matching: 6 minutes
3x3x3 final solve: 1 minute


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## Gprano (Jul 2, 2008)

That's exactly how i did it when i tried the 777 on gabbasoft.
I matched the tredges like the edges, breaking the 555 centers, exchanging with an unsolved tredge, restoring the 555 centers.
That worked, but i found it very slow...


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## Derrick Eide17 (Jul 2, 2008)

i came up with something like this for the FINAL 2 centers. i think it works well and its how i am going to solve them i think (for now) so like create 3 1x5 bars on 1 face and the other 3 1x5 bars is pretty much almost done. then finish filling in list few centers around outside with commuators (3 at most)
then solve last corner centers just like 5x5 centers.


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## masterofthebass (Jul 3, 2008)

Erik gave me the idea of somewhat doing this. Instead of building 1x5 blocks, you just build the inner 3x3 block. Then you extend that block with a couple of 1x3s and then fill in the 2 outer 1x5s I've been using it and to a degree of success


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## Jack (Jul 3, 2008)

masterofthebass said:


> Erik gave me the idea of somewhat doing this. Instead of building 1x5 blocks, you just build the inner 3x3 block. Then you extend that block with a couple of 1x3s and then fill in the 2 outer 1x5s I've been using it and to a degree of success



That was actually the method I came up with when first trying 6x6 and 7x7 computer cubes. It seems like it could be about as fast as the 1x5 block method.


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## Jason Baum (Jul 3, 2008)

masterofthebass said:


> Erik gave me the idea of somewhat doing this. Instead of building 1x5 blocks, you just build the inner 3x3 block. Then you extend that block with a couple of 1x3s and then fill in the 2 outer 1x5s I've been using it and to a degree of success


That's basically what I've been doing on 6x6x6: build the inner 2x2 block, add a 1x2 block, add two 1x3 blocks, and add the final 1x4 block. It's pretty nice. I like it better than just buildilng four 1x4 blocks.


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## Derrick Eide17 (Jul 3, 2008)

masterofthebass said:


> Erik gave me the idea of somewhat doing this. Instead of building 1x5 blocks, you just build the inner 3x3 block. Then you extend that block with a couple of 1x3s and then fill in the 2 outer 1x5s I've been using it and to a degree of success



lol i told erik one time that thief! nah im prety sure he came up with something like that first. 

*ponders*


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## TimMc (Jul 3, 2008)

My slow method:
- 3x3 centers on each face
- Extend to 4x4 centers on each face (keep them aligned so that you've a slot to work with)
- Complete Down and Upper layers by any means
- Solve the remaining 4 * 4x1 center edges
- Solve the remaining 4 * 5x1 center edges

*shrug*

Tim.


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## masterofthebass (Jul 3, 2008)

On 6x6 I just build the 1x4 blocks, since they are pretty quick. On good solves I get in the 1:30s right now. For the 7x7, my centers are up in the 3:30s  I need to work on speed during centers, as they can be much faster.


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## Erik (Jul 3, 2008)

Derrick Eide17 said:


> masterofthebass said:
> 
> 
> > Erik gave me the idea of somewhat doing this. Instead of building 1x5 blocks, you just build the inner 3x3 block. Then you extend that block with a couple of 1x3s and then fill in the 2 outer 1x5s I've been using it and to a degree of success
> ...



Hey hey, I just gave him the idea, I didn't say it was MY idea, cause in fact it clearly isn't.


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## Stefan (Jul 3, 2008)

masterofthebass said:


> This is almost impossible. Have you tried this? The only way to get the outer "tredges" is to use commutators, which isn't very fast.



No, you can do it just like edges with the usual five moves for pair-replace-otherPair. And you even have more freedom/choices for the replace part.

I have tried it, but not often enough to compare it to building 1x5 blocks (which I've used more often). And my cubes are unlubed and stiff, so I'm pretty slow anyway.

I'm also thinking about just using it for the last two centers. I start those by solving their inner 3x3 centers anyway. Which btw has the benefit that these centers would need pure inner slice commutators while the outer centers can be solved partly with double layer commutators.


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## RobinBloehm (Jul 3, 2008)

StefanPochmann said:


> masterofthebass said:
> 
> 
> > This is almost impossible. Have you tried this? The only way to get the outer "tredges" is to use commutators, which isn't very fast.
> ...



Yes, that's what I do for the last center, too. Swapping two inner center is really annoying, so I build the 3x3 block in the middle, usually being able to add a few pieces while doing that to have almost 3 1x5 blocks instead of only the 3x3, then sometimes swapping two full bars of the remaining 1x5 blocks, and now solving up to 4 single pieces with double layer commutators or maybe two pieces at once if they are on the same slice.


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## aznblur (Jul 3, 2008)

For last 2 centers, its not hard to create 1x5 strips in the middle. But the outer 1x5 strips are harder, and normally there is one piece that is wrong in each of the strips. So for me, I only have to swap 2 center pieces.

But this is an interesting idea, I shall try it out.


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## mrCage (Jul 3, 2008)

OK Stefan, I will curse a little bit 

In all honesty i would instead use as much as possible the same easy technique as for the 5x5x5 centers. For the harder cases use easy commutators. The center commutators are as easy to understand as cotton (!!!) after minimum practice with them :-D Who said a hybrid method is not allowed ??

- Per


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## masterofthebass (Jul 3, 2008)

Guys, for the last 2 centers, I have a maximum of 2 commutators to do, which end up being the oblique centers Everything else can be solved relatively easily. I start off building the center 1x5 block on once face. I then build a 1x5 in the next outermost layer, and then the next, giving me half of the face solved. Then, I pair up the inner 1x3 block just like 5x5 and then attach the 2 outer obliques to it. Then, I attach the outer xcenters with the outer T and then se commutators for the last 2 obliques. It goes really smoothly and has very few commutators.


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## ExoCorsair (Jul 3, 2008)

Meh, just do it freestyle with commutators for the last two.


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## Mike Hughey (Jul 6, 2008)

I just wanted to mention I did try Stefan's original idea as I said I would, and it certainly worked fine, so I really don't understand why Dan said it was impossible. It's a completely successful functioning method. No need for commutators at all - if you use the AVG method of pairing tredges and use the same method here for centers, the same kinds of moves work just fine (except that sometimes you have to do slice moves to get the pieces in place). (Maybe this method just doesn't work with the bigcubes.com edgematching method? It really works fine with AVG.)

However, that being said, my most recent solve prior to trying it was 13 minutes, but my first attempt using Stefan's original suggestion took 23 minutes. (centers: 8 minutes vs. 18 minutes) So it was outrageously S-L-O-W. But it worked just fine.

I would guess that with some practice this could become a much more reasonable method. But I doubt it could ever become really super fast. It's just faster to line up 1x5 blocks, I think.

I will probably keep trying this off and on as I hopefully get more decent at 7x7x7; I'd like to think that someday I can get this method sub-10. It certainly should be possible to do that. The neat thing about that is that then most of the cube is solved with the AVG edgematching method.


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## masterofthebass (Jul 6, 2008)

I thought it was impossible because I couldn't figure out any way to pair up the "edges" Personally, i think it's a very slow idea, so I really didn't put too much effort into figuring out a way to do it.


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## rubiksfriend (Jul 6, 2008)

Actually, I solve a 1x1x5 band, insert two outside 1x1x5 bands, then the remaining inner 1x1x5 centers.


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## Stefan (Jul 6, 2008)

I tried this a few more times and the general version is still slow for me (about 33% more time than my "normal" way). But for the last two centers, I often do this, and like it.


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## Joël (Jul 7, 2008)

masterofthebass said:


> Erik gave me the idea of somewhat doing this. Instead of building 1x5 blocks, you just build the inner 3x3 block. Then you extend that block with a couple of 1x3s and then fill in the 2 outer 1x5s I've been using it and to a degree of success



That's exactly what I have been doing intuitively.  Works for me.


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## Joël (Jul 7, 2008)

I tried your idea once Stefan... I have to get used to it a lot, but it's not a bad idea... I was already used to making one face at a time.


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## mrCage (Jul 7, 2008)

Hmmm ....

I really need my (taxfree this month) salary, and order those cubes. I see thay are constantly re-stocking, not much. Just little by little.

My last 2 checks were as follows

5x5x5:
127, 136

5x5x5(black):
104, 139

6x6x6:
103, 215

7x7x7:
81, 206

Cheers!!

- Per


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## AvGalen (Jul 7, 2008)

I only did a couple of solves (weekly competition) and centers were harder then expected (I suck at commutators during speedsolving. It takes me > 1 minute to "develop" one). I basically tried about 10 things for centers afterwards and the one I liked best was "spiraling out" by doing edge, corner/edge-pair, corner/edge-pair, row:

For 7x7x7 this means you do this (think of the centers as coordinates A1 to E5)
A1 B1 C1 D1 E1
A2 B2 C2 D2 E2
A3 B3 C3 D3 E3
A4 B4 C4 D4 E4
A5 B5 C5 D5 E5

1 dot in the middel (C3) = start
-----
-----
--x--
-----
-----

Attach 1 central edge (B3) = edge
-----
-----
-xx--
-----
-----

Attach 1 central edge + 1 central corner (B2+C2) = corner/edge-pair
-----
-xx--
-xx--
-----
-----

Attach 1 central edge + 1 central corner (D2+D3) = corner/edge-pair
-----
-xxx-
-xxx-
-----
-----

Attach 1 central edge + 2 central corners (D4+C4+B4) = row
-----
-xxx-
-xxx-
-xxx-
-----

Attach 1 outer edge + 2 outer wings (A4+A3+A2) = edge
-----
xxxx-
xxxx-
xxxx-
-----

Attach 1 outer edge + 2 outer wings + 1 outer corner (A1+B1+C1+D1) = corner/edge-pair
xxxx-
xxxx-
xxxx-
xxxx-
-----

Attach 1 outer edge + 2 outer wings + 1 outer corner (E1+E2+E3+E4) = corner/edge-pair
xxxxx
xxxxx
xxxxx
xxxxx
-----

Attach 1 outer edge + 2 outer wings + 2 outer corners (E5+D5+C5+B5+A5) = row
xxxxx
xxxxx
xxxxx
xxxxx
xxxxx

This spiraling allows for a lot of freedom during the solve and you get a lot of "just attach" situations. It also works for even cubes, you just have to add a start piece because those are nog always there.

And most importantly, if you see something nice; Use it! Many times you can get about 50% of the centers done in about 10 moves. Even if you end up breaking/repairing some of that later you save a lot of moves and get better look-ahead.


I also tried and liked "bars/squares inside out"

Start
-----
-----
--x--
-----
-----

Attach 1 edge
-----
-----
--x--
--x--
-----

Attach 1 more edge
-----
--x--
--x--
--x--
-----

Attach 1 row
-----
-xx--
-xx--
-xx--
-----

Atttach 1 more row
-----
-xxx-
-xxx-
-xxx-
-----

Attach 1 edge
-----
-xxx-
-xxx-
-xxx-
-xxx-

Attach 1 more edge
-xxx-
-xxx-
-xxx-
-xxx-
-xxx-

Attach 1 row
xxxx-
xxxx-
xxxx-
xxxx-
xxxx-

Attach 1 more row
xxxxx
xxxxx
xxxxx
xxxxx
xxxxx

And this also works for even sized cubes


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## mrCage (Jul 7, 2008)

Hi 

I have read in many posts already about making those 1x1x5 bars. How is that done (in some detail). What i figure is that they are built on some other layer and then inserted. Does this still work with only 2 unsolved faces to solve ? etc ....

- Per


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## AvGalen (Jul 7, 2008)

mrCage said:


> Hi
> 
> I have read in many posts already about making those 1x1x5 bars. How is that done (in some detail). What i figure is that they are built on some other layer and then inserted. Does this still work with only 2 unsolved faces to solve ? etc ....
> 
> - Per


Yep, you build the bar/line/row on another face and then attach it to the correct face. This doesn't work really well for the last 2 faces. It is basically done like in this video, only with 5 pieces instead of 3. There are no algs, only intuition


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## alexc (Jul 7, 2008)

AvGalen said:


> mrCage said:
> 
> 
> > Hi
> ...



It works for me for the last two faces! I first build the middle 1x5 which is pretty easy because you have room to work with. Then I add on the inner 1x5's which I find is also easy. Then I put in the outer two. The last step is the most difficult. Here's how I do it. I try to connect the outer + center with the two corner centers, at least. (I will connect an oblique too if I can.) The point is I don't need to finish the 1x5 before inserting it. So, say you have the two corners and the outer + center connected. Insert this onto the correct face. Then, to solve the remaining obliques use Rw U' l' U Rw' U' l and its reflection. Repeat for the final 1x5.


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## mrCage (Jul 7, 2008)

Hi 

I'm getting the feeling that this bar-building business is really only a camouflaged commutator. Nothing wrong in that of course 

- Per


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## AvGalen (Jul 7, 2008)

Off course it still works, just not as well as for the first 4 centers. For the first 4 centers it is just "position, move out of the way, restore". For the last 2 centers it is basically a commutator or another type of alg

For the last two centers I have been using this order (only done about 10 solves so probably not the best way to do it)

1: Inner 3x3 centers (B2-D2,B3-D3,B4-D4. This is easy)
2: Most other centers (very easy) using just a couple of moves
3a: Solve remaining outer corners (A1,E1,A5,C5 with wide-sune(s) (Rw U Rw' U Rw U2 Rw')
3b: Solve remaining outer center-edges (C1,A3,E3,C5) using an "alg"/intuition like Rw S U2 S' U2 Rw'
3c: Solve remaining oblique(s) using a simular "alg" (or just intuition as alexc


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## Stefan (Jul 7, 2008)

Arnaud: simular


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## AvGalen (Jul 7, 2008)

StefanPochmann said:


> Arnaud: simular


[checker off]and i forgod an klosing brakket two. Its plane too si dad mine english sugs. im affraid i wil ceep makeing simular misstakes indefiantly.[chekker on][chegger on][checkker on][checker on] => auto-corrected to [/checker off]

What about the actual content of my posts? Do you like any of these reductions?


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## Stefan (Jul 7, 2008)

Yeah, sorry, you just write that quite often, and since it's actually a correct word with a quite different meaning...

Apparently like you, I don't like building five 1x5 blocks. I'm doing it somewhat like you, first I build the inner 3x3 centers square like I'm used to from the 5x5 cube, then I add two opposite 1x3 center tredges, then the remaining two 1x5 blocks. I'll try your spiraling out as well as your above 1/2/3abc, which apparently the fast guys use, too (those I've watched).

Btw, I think the main reason I started this thread was people asking for help because they had trouble solving the last two centers at all. So it was an idea to solve it with a technique they already knew (from solving edges).


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## AvGalen (Jul 7, 2008)

[spelling]I don't mind people correcting my English, but after writing such a detailed post I thought it was weird that your reaction was: "simular"

Somehow I keep messing up the same words over and over
plane/plain
indefinitely (I am not the only one)
then/than
to/too
of/off/offcourse
simular/similar
[/spelling]


> I'm doing it somewhat like you, first I build the inner 3x3 centers square like I'm used to from the 5x5 cube, then I add two opposite 1x3 center tredges, then the remaining two 1x5 blocks.


 I don't think this is "like" me. It is exactly how I described "bars/squares inside out" (unless you do the inner 3x3 differently).

And I didn't understand your topic was about the last two centers. Could you give a scramble and a solution?


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## mrbiggs (Jul 7, 2008)

AvGalen said:


> Off course it still works, just not as well as for the first 4 centers. For the first 4 centers it is just "position, move out of the way, restore". For the last 2 centers it is basically a commutator or another type of alg



I've been using the exact same method you posted earlier for the first four centers, but I used it on the last two as well. I solve the inner 3x3x3 like I would on a 5x5x5. To triple the oblique centers I've been doing something like (I don't have the cube with me so there might be a typo):

3R' U2 F 2R U2 2R' F' 3R

where 3R is the third R slice, 2R is the second, etc.

and now there's a matched up triple on the U face, near L which I can insert the same way I do the inner 3x3x3. It's the same pair, move out of the way concept, just done on two instead of three faces. It's not the fastest method in the world, but I only have to do it about twice per solve.


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## Stefan (Jul 8, 2008)

AvGalen said:


> > I'm doing it somewhat like you, first I build the inner 3x3 centers square like I'm used to from the 5x5 cube, then I add two opposite 1x3 center tredges, then the remaining two 1x5 blocks.
> 
> 
> I don't think this is "like" me. It is exactly how I described "bars/squares inside out" (unless you do the inner 3x3 differently).


Yes, I do the inner 3x3 differently. For example if these are U and F:


```
???
O?O
???

??O
?OO
??O
```

Then M' U M builds a 2x3 centers block on F. And other stuff, too.



> And I didn't understand your topic was about the last two centers. Could you give a scramble and a solution?


It kinda wasn't, at least I didn't present it that way. Rather than typing this, I'd show it on video, but that might have to wait until after US Open. But it's not that special/hard anyway, is it?

Last night I tried the spiraling on the 6x6 and realized I had been violating your "if you see something nice; Use it!" principle. For example after extending the inner 2x2 to a 2x3, I always extended to a 2x4, even if the additional 2x1 was actually a 3x1 so I could've extended to 3x3 rather than 2x4. Now I think that was quite stupid, as it wastes an opportunity and makes further extensions harder.


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## UMichSpeedCubist (Jul 8, 2008)

StefanPochmann said:


> An idea to solve the 7x7 centers: Reduce to 5x5 centers.
> 
> Step 1) Build 3x3 centers on all sides like you would on a 5x5.
> Step 2) Build "center tredges" like you'd build tredges on a 5x5.
> ...


I've been doing this for over 1 year on gabbasoft's 7x7. I had the idea pretty early. And it doesn't show much promise. It's something to add to the arsenal, but the recognition is pretty tough even after I've practiced it for a long time. There are cases when the a center triple is already done, I can place using the "outer-5x5" route and that saves a lot of time.

But in general, it's fairly risky for me and I've switched back to doing full columns now. Making the inner/central 3x3 block is very fast for me since I know almost every optimal case, but then the outer +centers might take a lot of turns for me.

Although I have learned some new tricks this week, perhaps it still has merit. Either way, it's probably the most fun way of solving centers on 7x7! The way I do it is 1 entire face at a time, not all the inner/central ones first and then go back and do the outer stuff.... I think I'd lose a bit of focus if I did it your way. Although I might have tried that once or twice. Need to experiment more for sure.

Btw, I do very little 6x6 solving. It might be really nice way of doing those centers as someone else here said earlier.


-Doug


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## AvGalen (Jul 8, 2008)

[directed to Stefan]
I think we will end up discussing the V-Cubes and their solving methods a lot during the US Open.

Did you like the spiraling idea?
[/directed to Stefan]


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## Stefan (Jul 8, 2008)

Yes, I like spiraling. Although, I might "change direction" at any point. So a better name might be "growing rectangle staying as close to square as possible". Or maybe that's too long.


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## AvGalen (Jul 8, 2008)

I also change direction sometimes so we need to change the name of this method to "growing rectangle staying as close to square as possible while if you see something nice; Use it!". From now on this can be shortened to SPAVG Centers which reflects both you and me while retaining a SPiral like name 

It's a little like a freestyle continously inverted Fermat spiral, but SPAVG Centers sounds good to me


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## shvak1 (Jul 10, 2008)

good idea but you only really need to do that on the last two centers


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## bodom (Jul 10, 2008)

There are algorithms to move just two center pieces (which is technically a three cycle move), but they are slow and not advisable for doing the last two centers.

Stefan has the best approach. It took me a bit to warp my mind around the concept of center tredges, but I'm used to it. Had to keep straight when to do 1, 2, or 3 slice moves. The problem for me now is I have to mirror some of my algorithms as I now have "left" and "right" tredges. I can also mirror them with swapping "forward" and "back" as well.

I could get away with always tredging on one side using edges, because each edge has two sides. But with centers, they are each independent, so I have to do the mirror algorithms as well.

1x5 center matching is not good for long run.

Basically, your plan should be this:
1. 3x3 centers
2. center "left" tredges
3. center "right" tredges
4. 5x5 centers (done just like 3x3 centers)
5. inner edge tredge pairs
6. outer edge tredge pairs
7. do 3x3

Your centers are like this (going one step further)


```
GEDFG
FABAE
DBCBD
EABAF
GFDEG
```

There are 7 separate centers. Each center has four possible locations (outside of the main center (C)). Your 3x3 centers match up your A, B, C centers. I then do the DE tredge pairs. Then I do another 12 pairs for the DF pairs. It's important to differentiate early on between E and F centers. Once you build your DEF tredges, then ABC becomes your super center and the G centers are just like 5x5 corner centers.


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## StachuK1992 (Aug 14, 2008)

I am really having alot of trouble with my new(got it today) 7x7
I have worked with it for 4 hours straight and have gotten this far on my own:
first 4 centers
quintedges
3x3
could someone please supply me with a commutator or 2 that I could play around with
a quick video would be greatly appreciated
ummm. Thanks!


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## StachuK1992 (Aug 14, 2008)

any1???????


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## rjohnson_8ball (Aug 14, 2008)

The methods above for solving the last 2 centers are probably better for real big cubes, but I haven't mastered them yet. Instead, here is a simple algorithm to swap one cubie on the F face with one cubie on the U face:

U? ( r f ' r ' f ) U? ' ( f ' r f r ' )

The r and f indicate the particular slices that contain the bad center cubies.
Before you begin the algorithm, prepare the F and U faces so that the bad cubie on the F face would move to the bad cubie position on the U face if r is done. The first U? moves the bad cubie out of the way on the U face. The (r f' r' f) does a 6 dot pattern. Note the bad cubie on the F face has moved up to the U face. The U?' moves the bad cubie back into position. The (f' r f r') undoes the 6 dot pattern, and returns the bad cubie on the U face to the F face.

I prefer to complete the last 2 centers before connecting edge cubies.


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## AvGalen (Aug 14, 2008)

I just PM'ed this to Stachuk1992. I think it is more usefull to keep this type of info on the forum:

I am making a video tutorial this weekend, but for now you can try these 2 algs:
(3R means the 3 rightmost layers. 3r means the 3rd layer from the right)
R (U' L' U) R' (U' L U)
R (F B') U2 (F' B) R'

Now try doing them on multiple layers (like 2R) or innerslices (like 2r)
3R (U' 3L' U) 3R' (U' 3L U)
3R (U' 2L' U) 3R' (U' 2L U)
3r (U' 3l' U) 3r' (U' 3l U)
3r (U' 2l' U) 3r' (U' 2l U)

3r (3F 3B') U2 (3F' 3B) 3r'
2R (3F 3B') U2 (3F' 3B) 2R'
2R (2F 2B') U2 (2F' 2B) 2R'

And slice-sunes are usefull as well: 
3r U 3r' U 3r U2 3r'
3R U 3R' U 3R U2 3R'


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## StachuK1992 (Aug 14, 2008)

this looks farmilliar
thanks..this really helped alot...and I only tried a few so far


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## LarsN (Aug 17, 2008)

I'm not likely to be one of the fastest on the 7x7 with an average of little more than 9 minutes, but here's how I do the last two centers.

At first I look for simple slice swaps. If a slice has at least 3 wrong centers and there's a similiar slice on the other face with at least 3 wrong centers, I swap them using: slicemove U2 slicemove' 

I do 3 or 4 swaps, and end up having on average 3-5 centers wrong on each face. The I do single centerswaps like in this example:

U-face center:
xxxxx
xxxxo
xxxxx
xxxxx
xxxxx

F-face center:
ooooo
oooox
ooooo
ooooo
ooooo

Usings Arnauds notation
Commutator (or wosname...): 2R' F 3r' F' 2R F 3r

Often you get cases where you can switch more than one center:

U-face center:
xxxxx
xxoxo
xxxxx
xxxxx
xxxxx

F-face center:
ooooo
ooxox
ooooo
ooooo
ooooo

Usings Arnauds notation
Commutator (or wosname...): 2R' M' F 3r' F' 2R M F 3r

I'm not so sure of the 7x7 notation, but I hope it makes sense.


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## mrCage (Aug 19, 2008)

Hi Arnaud 

All of these are intuitive if i have understood notation correctly ...

- Per


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## rachmaninovian (Aug 19, 2008)

i have to do a lot of block cycles while doing centres last  i think i know all of these cases


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