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Roux 4b to 4c Transition

Athefre

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For years the 3-cycle recognition in Roux 4c was my least favorite part of the method. It seems I'm not alone because I sometimes see users, even the fastest ones, mention or ask about delays in recognizing the 3-cycles. No one ever gives a satisfying answer. I have a way that works. Everything you need is visible several moves before the end of 4b. With a short time of practice you'll be able to predict the first three moves of 4c before you've finished 4b.

While finishing 4b, there will be a sticker on the U layer in the corner slot you're trying to solve. Remember its color and it will go to the D layer when you're finished. There is another sticker on the U layer that matches it. It will stay on the U layer. When you've finished 4b, adjust the U layer so that the matching U layer edge you found is on the opposite side of the cube from the D edge. Finally, one of the edges on the U-layer doesn't match the U center. Bring it towards the U layer with MU2 or M'U2.

Many thanks to PandaCuber for the video.

Text Examples:
  1. U' M U' M2 U2 M2 U2 M U' M' U M2 U2 M U2 M U M U2 M U' M' U2 M2 U2
    • UMU'M'U'
    • You know that next you will do M'U2M'. Before doing that, look at the sticker at UB and you know it will go to DF afterwards. Then, while doing M'U2M', you find the edge sticker on U that matches the sticker that is going to DF. It is at UR and will end up at UL.
    • Now do U to place that U edge on the opposite side of the cube from DF. M to bring the edge that doesn’t match the U center towards U. U2M to finish.
  2. U M' U2 M2 U' M' U' M2 U M' U' M2 U2 M' U2 M U M2 U2 M U' M2 U'
    • MU'M'U2MUM'U
    • Of course next comes MU2M. Before doing that, look at the color of the sticker at UF and know that it goes to DB. While doing MU2M find the sticker on U that matches the sticker going to DB. It is at UL and will end up at UR.
    • U to place the U edge on the opposite side of the cube as the D edge. M to bring the edge that doesn’t match the U center towards U. U2MU2 to finish.

  3. U2 M U M' U' M2 U2 M' U2 M U' M2 U M' U2 M U' M' U M' U M U' M
    • You know to do MUM. You should have noticed, before starting, that L and R will be solved during this orientation. So while doing this, you watch the sticker that is at RU. It goes to DF. And you know to watch for its matching U sticker. It ends up at UR.
    • Solved.
    • U’ to place the U edge on the opposite side of the cube. M’ to bring the edge that doesn’t match the U center towards U. Finish with U2M’U2.
Extra:
  • This will not interfere with your strategy for anticipating cases other than the 3-cycles.
  • The two 3-cycles that start with M2U2 are solved with a total of one U2 more.
  • Rarely you'll come across the orientation sequence MUM' solving 4b along with it. In this case it's impossible to see either D sticker. You can check LU or mix in another strategy.
 
Last edited by a moderator:

Athefre

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Yeah I have got a strategy similar to this. I identify BU sticker as I insert LR edges.

How do you know which edge belongs at BU? After 4b, the corners are positioned so that the only edge at BU is L or R. One motivation I had for posting this topic is you mentioned in irc that you have to do things like U'U2 for some cases.
 

5BLD

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I did mention that, it was the case until I came up with the strategy I use now.
What I meant was I look literally at the edge coming to BU AFTER 4b, during step 4b. You see the BU edge comin into place as you do the last move at the end of 4b which is almost always a U move. If LR skip, fine, I'll have to do UU' to recog but I can predict 4b skips and see the BU edge before it goes there anyway.
 

Athefre

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How do you know which direction to adjust U? What I'm presenting here is a way to not have to think about how to adjust the U layer after 4b and to not have to think about in which direction to bring M.
 

Athefre

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The great thing about this is that you will never have to look at F, R, L, B, or D. Not even LU, RU, FU, FD, etc. It is done completely by looking at two stickers on the U face and the U center if you want. Once you've done that, you can look away from the rest of the solve up until the final two moves.
 

Athefre

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M' U2 M U' M' U M2 U2 M' U2 M2 U M U' M2 U M2 U M U' M U' M U'

a. MU'M'U2MUMU2

b+c. Now, before slotting the two LR edges, notice the sticker at UB, which will go to DF, and its match at UR, which will go to UL after M2. You can also notice that the U center doesn't match those two stickers. So do M2 then U' to place the matching stickers on opposite sides of the cube. If you paid attention to the U center like I mentioned, you already know to do M'. If not, you can spend your time here finding the edge that doesn't match the U center. U2MU2M2 to finish.

M2 U M U2 M2 U2 M' U' M' U M U M2 U2 M U M U2 M' U' M U2 M' U2 M'

a. U'MU'M'U

b+c. Notice the matching stickers at UB, which will go to DF, and UR, which will go to UL after M'U2M'. You could also notice that the center matches those two stickers and know that after you do M'U2M', the matching sticker still on the U layer will be the one that needs to be brought towards U. So do M'U2M' then U to place the matching U layer sticker on the opposite side of the cube then M to bring it toward U since it doesnt' match the U center. U2MU2M2 to finish.

M U' M2 U M2 U' M U' M U' M2 U' M U2 M' U M U M' U M U' M U M

a. UM'UM'U2MU'MU

b+c. Matching stickers at UB, which will go to DF, and UL, which will go to UR after you do M'U2M'. So do M'U2M' then U' to place the matching U layer sticker on the opposite side of the cube from it's matching D sticker. If you paid attention to the U center earlier you know to do M' because the edge at UF doesn't match the U center. U2M' to finish.
 

chardison1980

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ive been going through these as i have gotten into roux as my primary method still transitioning over from waterman,

do you think you can make a couple videos showing this by any chance
 

chardison1980

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I did mention that, it was the case until I came up with the strategy I use now.
What I meant was I look literally at the edge coming to BU AFTER 4b, during step 4b. You see the BU edge comin into place as you do the last move at the end of 4b which is almost always a U move. If LR skip, fine, I'll have to do UU' to recog but I can predict 4b skips and see the BU edge before it goes there anyway.
is there a chance that you will be adding your new strategy that you use now to the ROUX site in a video? thanks
 

Athefre

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I'm unable to make a video. All I can do is say that I know what I'm talking about. I used many different techniques, including user suggestions and others of my own, for 5 years and wasn't satisfied. I've been using this for close to a year and it feels perfect.

To everyone: Try it. Use this for a while. Maybe even just give it 30 solves to get used to it.
 

chardison1980

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I'm unable to make a video. All I can do is say that I know what I'm talking about. I used many different techniques, including user suggestions and others of my own, for 5 years and wasn't satisfied. I've been using this for close to a year and it feels perfect.

To everyone: Try it. Use this for a while. Maybe even just give it 30 solves to get used to it.

its still a little confusing to me, but im messing with it alot now, trying to get it to click. but im still relalivly new at ROUX also.
 

Athefre

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Our methods are similar but with a different approach...

From what I've seen, it doesn't seem similar at all. What is similar to mine is Donovan's. He doesn't provide any kind of look ahead planning like I've described to get to the goal, but in his tutorial video, his idea is exactly the same as mine.

[youtube]ac6L6x-NEm8&feature=related#t=8m24s[/youtube]
Skip to 8:24.

The difference is that I have developed a look ahead strategy to avoid having to find those pieces after 4b. You know how 4a and 4b are like one step? With what I'm describing, 4b and 4c are like one step. No AUF hesitation and no first M direction hesitation.
 
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The really cool thing of Athefre idea (IMHO) is that lookahead for 4c starts during 4b.

EDIT: I edited this post to reflect my current knowledge.

NEW Titel: (Donovan's) Singleton Prediction System

I just watched the video from Post 16 and now discribe (extend) the Step 4c prediction system, that is used there.

During 4b there is the "double slot-in move", that's when UR edge und UL edge are brought into position together.
exsample: let 4b be M'U2M' then the bold M' is the "double slot-in move"

It starts directly BEFORE the "double slot-in move".

Ia) The double slot-in move" can be M, M' or M2 - lookout for a "Singleton" that will be moved to the D-LAYER.
Ib) Remember where in the D layer the singleton will be.

A "Singleton" is an edge that has not the same sticker color than "ALL VISIBLE" adjacent centers stickers. In our case we only see
the U and F center.

(math pedantic: from this definition a Singleton is no Singleton any more when moved to D layer, but for simplycicity I
will still call it that way)

Ia advanced) if the double slot-in move is M or M' the singleton is allowed to be DF, or if no singleton is visible then DB becomes the singleton.

Ib advanced) BLOCKS RULE - just this: if you spot a big block (3 same colored stickers in a row, two centers and there edge), you must use that knowledge to shortcut the solving.

II) after the "double slot-in move" look for a new "singleton" and do U layer turn to position it directly vertical above
the singleton from step I ; then do an slice move to bring both songletons in the U layer.

III) continue with 4c like normal.

PROs (not why this kind of methode is good just whats good at singleton):
- while double slot-in move your brain really has no other dutis.
- no cube twists
- if solving the dot-case with out E you save a move

CONTRAS
- Very new/rare, maybe additonal bad cases exist
- Setup: M' U2 M' U' M - this seems to be a bad case with for the singleton system.

QUESTIONS
Sometime there is no first singleton in U (in conjunction with M/ M' ), ... I just treat the other D edge as singleton in this cases. (yes, answer of my own)

So far I haven't checked completely, but there are situation where no (second) singleton exists, but that seems to be the U2M2U2 case wich is quite easy to recognize? (just go on and solve the cube)

Also I feel like doing 1 or 2 additional moves on average? (but therefor no cube twist or look arounds are necessary)


The great thing about this is that you will never have to look at F, R, L, B, or D. Not even LU, RU, FU, FD, etc. It is done completely by looking at two stickers on the U face and the U center if you want. Once you've done that, you can look away from the rest of the solve up until the final two moves.

You say you don't look at F,FU ... if UF and UB both don't have the same color as U (slot-in move is M2) ... FU, U tells me wich one could be a real singleton - how do you know this ?
 
Last edited:

LarsN

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Maybe it's just a force of habit, but it seems way more easy to look at RU and LU while doing what ever M-move in the end of 4b.

This way there are no additional moves, except for the dot case, which should be easy to recognize before the wasted move.
 

Athefre

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LarsN said:
Maybe it's just a force of habit, but it seems way more easy to look at RU and LU while doing what ever M-move in the end of 4b.

That's the point of my 3-cycle lookahead. There is no thinking about pieces at the end of 4b. All of the thinking was done 3 moves before the end of 4b.

oll+phase+sync said:
So far I haven't checked completely, but there are situation where no (second) singleton exists, but that seems to be the U2M2U2 case wich is quite easy to recognize?

Yes, I pointed out in my first post that my 3-cycle lookahead method doesn't interfere with those cases. You know if you will have a 3-cycle case or not before it is important to know.

oll+phase+sync said:
Also I feel like doing 1 or 2 additional moves on average?

I noted in my first post that the M2U2 3-cycles require one additional U2. It will not raise your movecount average by any significant number.

oll+phase+sync said:
You say you don't look at F,FU ... if UF and UB both don't have the same color as U (slot-in move is M2) ... FU, U tells me wich one could be a real singleton - how do you know this ?

There is no looking at FU. It is all done looking at two same colored stickers on U. Three if you incorporate the U center. The U center is how you know which piece is your "singleton".
 
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