[Help Thread] FMC Discussion

[irontwig]

IF still finds a 29 if you check "Other":

Spoiler

1 corner 3-cycle(s) and 1 edge 3-cycle(s) insertion(s) needed

D2 B2 U' R' D B D' B2 D' R' [@1] D R' D' R2 D L U2 L2 D' U2 F R2
Insert at @1: R2 D R2 D'
After the 1st insertion: D2 B2 U' R' D B D' B2 D' R D R D' R2 D [@2] L U2 L2 D' U2 F R2
Insert at @2: D B U' B' D' B U B'
Fewest moves: 29. 5 moves cancelled
The final solution: D2 B2 U' R' D B D' B2 D' R D R D' R2 D2 B U' B' D' B U B' L U2 L2 D' U2 F R2

 

[kbrune]

To the FMC pros. I'm looking to broaden my skills. Some info as to my current skill level. I use currently use Heise/block building to complete F2L. then I use cfop LL with some move optimal pll. I have recently learned to use the premove technique with pseudo blocks. And I have been working on using more of the heise final steps to eventually be able to use 3 corner insertions.

I don't know how to use inverse scramble yet and I don't fully understand what a skeleton is. I usually end up with solves from 40 to 48 moves.

Question:
I was working on this scramble from WC this week.
R2 D2 L' U' B D' B L2 U D2 F B R2 D2 B2 U2 L2 B L2 F2

I managed to get 26 to 4 corners. With these moves
Y2
B' R2 U' R2 L D F' D' L D' 2x2x3
X'
F' L F L' F U' F L F L' F' F2L-1
U2 L' U L U L4C

Are 4 corner cycles a thing? Is it worth keeping this or would an experience FMC solver look for something else instead?

 

[tseitsei]

To the FMC pros. I'm looking to broaden my skills. Some info as to my current skill level. I use currently use Heise/block building to complete F2L. then I use cfop LL with some move optimal pll. I have recently learned to use the premove technique with pseudo blocks. And I have been working on using more of the heise final steps to eventually be able to use 3 corner insertions.

I don't know how to use inverse scramble yet and I don't fully understand what a skeleton is. I usually end up with solves from 40 to 48 moves.

Question:
I was working on this scramble from WC this week.
R2 D2 L' U' B D' B L2 U D2 F B R2 D2 B2 U2 L2 B L2 F2

I managed to get 26 to 4 corners. With these moves
X2
B' R2 U' R2 L D F' D' L D' 2x2x3
X'
F' L F L' F U' F L F L' F' F2L-1
U2 L' U L U L4C

Are 4 corner cycles a thing? Is it worth keeping this or would an experience FMC solver look for something else instead?

Next thing you need to learn is insertions. That just means inserting commutator(s) somewhere in the solve to solve the last few pieces with as few moves as possible. Most common insertions are for 3 corners, 4 corners and 5 corners but also other types are commonly used. Insertions for 4C and 5C are really just doing 2 3C insertions one after another.
http://fmcsolves.cubing.net/fmc_tutorial_ENG.pdf is a very good overall FMC tutorial that also covers insertions very well, I strongly suggest reading it carefully.

Skeleton means the part of your solve that only leaves you with few unsolved pieces that you are going to solve with insertions. So skeleton is your solution before doing insertions.
Partly solution you have written in your post now is a skeleton that leaves 4 corners unsolved (the first X2 should be Y2 in your solution though). But this particular case of 4C is a bad one because one of the corners is in its correct place but twisted (this is always not good since it requires doing 3 3C insertions instead of 2 which obviously adds moves) and you should definitely search for something better.

Although experienced FMC solvers would search for something better even if the 4C case was a good one because 26 moves to 4C isn't that good for more experienced solvers. The general rule of thumb is (at least for me) that the skeleton leaving 3C is obviously best one and takes about 6 moves to solve usually 4C and 5C are almost equal compared to each other (maybe 4C is marginally better) and usually take something like 10-11 moves to solve. These are the numbers I use to decide what skeleton I pick for insertions. Example: I have a 25 move skeleton that leaves 3C and a 22 move skeleton that leaves 5C. My expected movecount for 3C skeleton 25 + 6= 31 and for 5C skeleton 22+10=32 ---> I would first search insertions for 3C skeleton and then if I have time check the 5C skeleton also...

 

[kbrune]

@tseitsei

Thank you for the detailed explanation and the link. Much appreciated!

Fixed the mistake as well thanks.

 

[TeddyKGB]

But this particular case of 4C is a bad one because one of the corners is in its correct place but twisted (this is always not good since it requires doing 3 3C insertions instead of 2

Incorrect.

 

[tseitsei]

Incorrect.

Oh yes you are correct. Stupid me....
With 4C you can have 1 twisted corner and still use just 2 comms to solve it. But no more than 1. With 5C you cant have any twisted corners. I dont know why I messed that up sorry

 

[Daniel Lin]

K for this weekly's FMC I didn't finish

Spoiler

scramble:L U B L' D F' R B D2 R U' D R2 F U' B L2 U' R2 B2

D F R F B'// EO
(B2 R B2)//2 P blocks and a pair

don't know what to do next
i tried this
D F2 L U2 L2 U2 L' U'//4e4c

both edges and corners are pure 4cycles. It might be possible to solve all 8 pieces in one move by putting them all on one layer. Or I could insert an alg. idk what the best option is

can someone pls help?

 

[Cale S]

K for this weekly's FMC I didn't finish

Spoiler

scramble:L U B L' D F' R B D2 R U' D R2 F U' B L2 U' R2 B2

D F R F B'// EO
(B2 R B2)//2 P blocks and a pair

don't know what to do next
i tried this
D F2 L U2 L2 U2 L' U'//4e4c

both edges and corners are pure 4cycles. It might be possible to solve all 8 pieces in one move by putting them all on one layer. Or I could insert an alg. idk what the best option is

can someone pls help?

Spoiler

D F R F B' // EO
(B2 R B2) // blocks and stuff
D F2 L U2 L // F2L - 1 + EO
U L U L' U' L U2 L' U' // to L3C

D F R F B' D F2 L U2 @ L U L U L' U' L U2 L' U' B2 R' B2
@ = [U R U', L2]





edit: here's 13 to 4e3c, IF gives 26

D F R F B' D F2 U2 L U B2 R' B2

 

[Bubtore]

Another good solve together with Emilien (we had the same skeleton).
I inserted and got 21, he solved the corners at the end and got 20, wtf ?!

S // B U2 F2 L D2 L2 F2 U2 F2 U2 L D L B U2 F' L' D2 R2 D2
I // D2 R2 D2 L F U2 B' L' D' L' U2 F2 U2 F2 L2 D2 L' F2 U2 B'

L F' // Pseudo 222
(D2 R' B) // EO
(U' R2 U D' R U R D U') // L3C

Skel // L F' D' * U R' U' R' D U' R2 U B' R D2 - 14

* F2 U' B U F2 U' B' U

Solution // L F' D' F2 U' B U F2 U' B' U2 R' U' R' D U' R2 U B' R D2 - 21

 

[Cale S]

25 for current Weekly FMC

Spoiler

scramble: D' R L2 B2 F2 R' D' B2 R' U2 L2 D2 R L2 F' B L' U' F2 L2

(U' B' L' R F') // EO + 2 pairs
(U R2 U) U // 2x2x2
(D R D' R') // 2x2x3
D' L2 D' L // to 2GLL
(R D R' D R D2 R') // sune
R D R' D R D2 R' D' // sune

Final solution: U D' L2 D' L R D R' D R D2 R' D' R D2 R' D2 U' R2 U' F R' L B U (25)

20 out of the 25 moves were RUD

 

[Bubtore]

Another funny evening with Emilien :
I've "found" this LL-skip, but we acted like retards ...

S // D' B' L2 D L B2 L F' B2 L' U' R D2 B2 D2 L2 U2 L2

U R' U2 D' B' // 123
F' L2 F D // 223
F2 U' R' F' R U2 // F2L-1
F2 R' D' F' D R F // Finish


Solution // U R' U2 D' B' F' L2 F D F2 U' R' F' R U2 F2 R' D' F' D R F - 22 Moves

So actually I had this here : F2 R' F2 R U F' U' F' // Finish, which gives me 23,
and didn't see the other solution even though it's the way I would do EO in a speedsolve.
Nor did Emilien, he looked at it and found a easy way to get to 3E3C and thus gave that to IF.
The programm inserted a 10 moves commutators which cancels all moves and gives the final 22 moves solution ...

edit : today's scrambles are from here
http://iwca.jp/competition/scrambles/competitionId/IranFMC2015/eventId/333fm
Best result for each attempt was 23 (me, should have been 22), 26 (him) and 23 (him) which makes it 24 (or 23.66 without failing) mo3
Funnily enough, our 2 means sum up at 52, and the winner of the comp had 52.33

 

[Emilien]

I really loved the last one, nothing for 40 minutes and in the last 20 ... :

L F' R' F R' L' B2 U' L' D' B U F2 L2 U R2 D2 L2 U' D2

R U B // Eo (3)
(U' R U R U' L' F2 D' B2 R') // L5C (10)

 

[Cale S]

this was pretty nice, lots of block possibilities

L2 U2 B2 L2 B2 R2 B' D2 B' R2 U2 R D' U' L2 U' L' R2 D U2 R2

D' B' // square
(D' L2) // another one
R' D2 F2 // another one
(B' D' R' B2) // pseudo F2L - 1
B U' R U B' R2 B // pseudo F2L + blocks
(B2 U' R' U R B U2) // LL

Final solution: D' B' R' D2 F2 B U' R U B' R2 B U2 B' R' U' R U R D B L2 D
23 moves

 

[porkynator]

[...]
B U' R U B' R2 B // pseudo F2L + blocks
[...]

Wow, really nice! I don't think I would have thought of temporarily destroying the block with 2 moves.

 

[Cale S]

24 for Weekly FMC with only 1 move cancel from insertion

Spoiler

scramble: U2 L2 R2 U' F L B' F L' R2 D L2 B F' D R' F' B' L R'

(D' F) // square
(L' B' L2) // another square
L D L' U2 // 2x2x3 + EO
R2 F2 R F2 R2 F R F' // to L3C

L D L' @ U2 R2 F2 R F2 R2 F R F' L2 B L F' D
@ = [R', U' L2 U]

Final solution: L D L' R' U' L2 U R U' L2 U' R2 F2 R F2 R2 F R F' L2 B L F' D (24)


I tried doing some weird roux stuff with a 3 move 1x2x3 and decent second block stuff but it didn't really work

 

[Attila]

Weekly FMC scramble:
U2 L2 R2 U' F L B' F L' R2 D L2 B F' D R' F' B' L R'

Unfortunately, I ran out of time

Spoiler

F R' D' L' F2 B R' orient corners and orient edges,
(D' F2 B2)
(R' U2 D2 L U' R2 U' B2 U' D LSE

 

[Robert-Y]

Some scramble I got whilst practicing 3x3x3:
R2 D2 B' U2 F D2 R2 F' L2 D2 U L2 F' L D R F' R

 

[Cale S]

Some scramble I got whilst practicing 3x3x3:
R2 D2 B' U2 F D2 R2 F' L2 D2 U L2 F' L D R F' R

D' // 2x2x2
F' // pseudo 2x2x3
L F' // F2L - 1
U' L U2 D' B' @ U' B D L // VLS to L3C

@ = [B, L' F2 L]

Final solution: D' F' L F' U' L U2 D' L' F2 L B' L' F2 L U' B D L
19 moves

3 minute FMC ftw

 

[Lars Petrus]

Hi everyone!

Following NISS solutions is a pain even for those who know how, so I made a web site that does the work for you. I hope people will like it enough to use it, and hate it enough to tell me how it should be improved.

As an example, here is a recent NISS solution from this forum (#3716 by Cale S):

http://birdflu.lar5.com/fmc?s=lublbrqdqruRpnln1rDur&n=pq(pl)Pdf(qpPb)BnRUqrB(bnPURBu)

 

[Mark Boyanowski]

Here are my solves for Mental Breakdown 2016, moves in parenthesis are done on inverse:

Scramble: R' U' F L2 F' D2 F U2 F L2 F' U2 R2 F' D' B U' B F L' R' U' F D R' U' F

Spoiler

(B' L' B U R') // EO + 2 2x2x1s
(U B' F2) // 2x2x3
(F D' F') // Block
(D' R2 D B' D B D2) // 4C

Skeleton: D2 B' D' B D' R2 D F @ D F B U' + R U' B' L B

@ = B' D F D' B D F' D' (Cancels 4)
+ = U' R' D R U R' D' R (Cancels 2)

Final(27): D2 B' D' B D' R2 D F B' D F D' B D B U2 R' D R U R' D' R2 U' B' L B

Unfortunately, I realized with 5 minutes left I could have done (R2 D') instead of the last line to get 12 to 3E3C, optimal 25. At least my insertions for the 17 to 4C were optimal

Scramble: R' U' F L2 D L2 D' U' F2 L2 U F L D U F R2 D L2 B2 D R U2 R' U' F

Spoiler

Ok, this one was a little silly.

(U2 F' R2 B) // 2x2x2
(D') // Pseudo 2x2x3
D // 2x2x3
(D R2 D2 R') // Block
(F2 R D F') // F2L -1
(F R F' R' F R2 F') // How dose you dose this pair?
(D' F D2 B' D2 F' D2 B D' R') // OLL into PLL skip

Final(27): D R D B' D2 F D2 B D2 F' D F R2 F' R F R' D' R' F2 R D2 R2 B' R2 F U2

I also found this:

(U2 F' R2 B) // 2x2x2
(D') // Pseudo 2x2x3
D // 2x2x3
(F' D R' D') // 2x2x2 + 1x2x3
(D' U F D U') // EO
(U R U' R U R2 U' R') // 20 to 3C, optimal 28.

Lastly, I found this:

(U2 F' R2 B) // 2x2x2
(D') // Pseudo 2x2x3
D // 2x2x3
(F' D R' D') // 2x2x2 + 1x2x3
(D' U F' D U') // EO
(U R U' F2 U R' U' F2 R') // Block comm to 2 twisted corners, in total 21 moves. Optimal is 26 I looked at insertions on it quickly near the end, but wasn't very thorough.

Scramble: R' U' F L2 D2 F' L2 B' U2 F U2 R D2 L2 F' D B' D2 R' U R2 D F' R' U' F

Spoiler

(U' B U2) // 2x2x1
(F' R F) // Another 2x2x1
(U' F U' F' U' R2) // 2x2x3
(B2 L' D L) // EO
(D' B2 D B D') // 3C

Skeleton: D B' D' B2 D # L' D' L B2 R2 U F U F' U F' R' F U2 B' U

# = U' L' D' L U L' D L (Cancels 6)

Final(23): D B' D' B2 D U' L' D' L U B2 R2 U F U F' U F' R' F U2 B' U

As you can see, there are a few disappointments for solves 1 and 2, where I could have gotten better solutions, but overall I'm still extremely happy with this mean