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The FMC thread

Kit Clement

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A typical but lucky FMC attempt

L2 D2 B D2 // 2x2x2 Block
U' B2 D' B U B' // 2x2x3 Block
R D R' D2 // F2L '1
F' R F R2 F' R2 F //F2L
R2 B' R' B' D B D' R B //OLL
R' F2 R U D' F2 U' D R F2 R2 //3e

41 ETM

Ending F2L differently,

L2 D2 B D2 // 2x2x2 Block
U' B2 D' B U B' // 2x2x3 Block
R D R' D2 // F2L '1
D R D' R' F D' F' D //F2L
D R2 D2 F D F' D R2 D' //OLL
D2 r' D R' D R D' r D2 B R' B' // 3c3e

43 ETM

critique this please
First off, including the scrambles always helps. I made one with cube explorer: R2 D2 B R B R2 L2 U' F U R2 B' R B (14 optimal? Are you generating purposefully easy scrambles?)

First: why did you AUF on OLL? You could have cancelled 3 moves between F2L/OLL and another 3 between OLL/PLL for a 35:

L2 D2 B D2 // 2x2x2 Block
U' B2 D' B U B' // 2x2x3 Block
R D R' D2 // F2L '1
F' R F R2 F' R2 F //F2L
F' R' F' U F U' R F //OLL
F' R F' R' F' R' F' R F2 R' //PLL

Going earlier, note that you have a 2x2x2 block far sooner than you say:

L2 //2x2x2 block

After this, you seem to want to extend the 2x2x3 normally, but it comes at making one of your pairs (blue-orange-yellow) difficult to preserve later. I think it's easier to work on this 2x2x1 extension first:

B2 D2 //+square

And then pace the blue-orange-white pair. You can now use this 1x2x3 to create a PS-F2L

U' B' U B' //PS F2L

You're now incredibly close to getting a skeleton, we can now focus on solving the green-red edge in a way that solves all edges:

D2 F D F' D' B //5c

This leaves 13 to 5 corners, which is a pretty good solve. Insertion finder gets a 25 for this when only using pure comms (24 if you use longer comms): https://fewestmov.es/if/8d5dd489479f724c7211bec0865266b7

Another interesting finish is by seeing some pseudo-slotting stuff at the PS F2L - notice you have a pseudo-pair built one move before the PS F2L-1 is built, so if you pick up after that step, you can first insert the edge, then insert the pseudo-pair and leave 3c in 16 moves:

L2 //2x2x2 block
B2 D2 //+square
U' B' U //F2L-1.5
D B' D B U F D2 F' U' D2 //3c

Insertion finder gives this an optimal finish of 23: https://fewestmov.es/if/779b0a88e58ddd1deaac4066f98eb262

I would try to give you advice using the F2L-1 that you gave, but the EO is just not good in that state to get good finishes. If we back up a bit to this point though:

L2 D2 B D2 // 2x2x2 Block

Notice that you're 1 move away from a 2x2x3. In your solution, you do:

U' B2 D' B U B' // 2x2x3 Block

Which is 6 moves to make a 2x2x3 instead, just to preserve a pair. Additionally, just doing the 1 move to finish the 2x2x3 and breaking the pair gives you much better EO (only 2 bad edges from Petrus orientation) so using 5 moves for a pair and bad edges is definitely not worthwhile. If we try that start instead:

L2 // 2x2x2 Block
D2 B D2 B2 // 2x2x3 Block

Notice that there are a lot of ways to finish the Petrus EO and get some pairs along the way too. One example:

D' F D2 F' // EO+pair

This is only 4 extra moves and is a lot easier to work with this EO. The parity is bad on this case though, so it doesn't lead to a great finish (that I can see, at least), but all other things considered equal, this is much better to work with than your 2x2x3 marked substep.

Also, if you don't know how to use NISS yet, you should. I didn't use it in any of these examples (mostly because this scramble was super easy already to find continuations on) but it will make your options for continuations much more plentiful and make it easier to work with pseudo-blocks.
 

trangium

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If I learn one method just for FMC, should it be Petrus, ZZ, Roux, or something else?
Most of the top solvers use Domino Reduction in most of their solves, so learn Domino Reduction. A guide for Domino Reduction can be found at
 

xyzzy

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2016XYZZ01
Hey guys, I tried DR for the first time. I achieved DR but I don't know where to go
U R D2 U' F2 R2 D //p222 U... (cubing.net)

can anyone end this and get a sub 50??
I kinda doubt you can start from a 44-move DR and finish in only 6 more moves…

Here's my own DR attempt for that scramble:
U (B2 U') // EO on U-D axis (3/3)
F // orient most of red face & solve two S-slice edges (1/4)
(R L' B' L' B) // left with 3 twisted corners and one S-slice edge (5/9)
(L F' L' F') // easy DR case (4/13)
(R U2 R' L' F2 R L2 U2) // orange layer (8/21)
(U2 F' U' F U R F R' F' U2 R' U R U' L') // F perm (15−2/34)

(I'm still pretty bad at DR (both in getting to DR, and in continuing after DR) so take this with a grain of salt.)

If you're going to do DR, it's not that useful to have a purely blockbuilding start because that locks out most of the moves you'd want to use to influence EO. For example, with a 2×2×2 block in DBL, that leaves the U, R, F faces free, and you get to use the F move for EO. At first glance it might seem like you get to flip four edge pieces at once with F moves, so there's no difference with doing EO right at the start, but the difference is that now you can no longer directly move bad edges to the DF or LF positions to flip them because the block is in the way. Also, even if you are going to blockbuild, you don't need to build "real" blocks; you can just build blocks out of oriented pieces and ignore the actual colours on them.

The power of DR comes from how you can affect corner orientation in very few moves when you don't have to preserve the belt. In normal solving, Sunes seem like pretty fast algs (7 moves makes it the shortest ZBLL), but with DR, you have even shorter "algs" for changing corner orientation: R U R', R U' R', and R U2 R' (3 moves).
 

xyzzy

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Another question:

Should I solve a belt right after EO and preserve it while doing CO or should I try to solve the belt after solving CO?
Solve 3/4 of the belt after EO, while forcing 3 or 4 twisted corners, then solve the last belt piece together with CO. If you know NISS, it's usually not too hard to set up to one of the 3-move cases.
 

Kit Clement

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Another question:

Should I solve a belt right after EO and preserve it while doing CO or should I try to solve the belt after solving CO?
Solving the belt directly is a waste of time given that you need to break it to finish CO. Using the simple triggers that xyzzy mentioned and setting up to those is the simplest way to go from EO to DR.
 
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R B2 U2 F //EO(Somewhat) D2... (cubing.net)
I got stuck again.....please help me
Btw I don't know NISS and I get confused whenever I sit down to learn it.

E: I got DR:

R B2 U2 F //EO(Somewhat)
D2 R' U2 F2 U' F' L' B L B' //belt + force CO on top+ break EO(accidentally)
U' R' L F R L' //fix EO
(F R' U2 R F') D2 (F R' U2 R F') D2 //DR
U2 R L' B2 R' L F' B L2 F B' //223
U F2 U2 F2 //47 to 6c2e(I highly doubt this) lol

I'm stuck here
 
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