Rubik F2L

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Main page Rubik's cube

Intro

Source: Tutoriel : Résoudre les F2L intuitivement

The principle is to always fall back in one of the 4 basic cases. A basic case is one that requires only 3 moves to solve:

  • Case /R1/: R U' R' and case /L1/: L' U L (mirror)
Pair next to each other, horizontal and left (right) of target slot.
  • Case /R2/: R U R' and case /L2/: L' U' L (mirror)
Corner above target slot, edge on UB. Corner white sticker facing right (left), front sticker same as edge up sticker.


Notes:

  • Always put the corner above the slot, and solve from the right side first, then switch to left if necessary.
  • In algorithm below, whitespaces indicate that we reached a basic case.
  • We can always replace U2 R U' R' with U sledgeR'.
  • Case solve are coded for fast reference. (R2, BR) means we want to get a basic case /R2/ by bringing the corner above BR corner. (R2, BR, rot) means we aim at obtaining a /R2/ case by using the BR corner, but this time with rotation of the corner; this means that the corner is moved above the BR corner not using a U move (followed by R ... R' that would preserve orientation of the corner), but with a R moves that changes orientation of the edge. So rot indicates that the solves change the F2L family.

There are 3 F2L families: sticker UP, sticker FRONT, and sticker RIGHT.

White sticker UP

  • Edge on 2L:
Rb F2LU2Lwrong.png
(2L1) Case 1, edge wrong (matching corner color)
  • Get the pair out, then reinsert R U2' R' y U2 (L' U L) (alt. R U2' R' U' F R' F' R')
  • Faster, FR: U' R' F R F' R U' R'
  • Faster, FL: left SH, or y', the subcase FR above.
  • Faster, BL: Victor uses L U' L' y' L' U2 L (B with RH index).
  • Faster, BR: usual is R' U R' F R F' R, Victor uses R' U R d' R U' R' ({{{1}}}.
Rb F2Lsexysexysexy.png
(2L2) Case 2, edge correct (not matching corner)
  • sexy sexy sexy.
  • Edge on LL, not touching: we get a basic base by (i) bring edge to its color, (ii) raise empty slot, (iii) bring corner above the edge, then (iv) turn back slot. All cases below are identical.
  • (LLBU1) Edge on BU, case 1: U R U2' R' R' F R F'
  • (LLBU2) Edge on BU, case 2: y U2' L' U' L L F' L' F
  • (LLLU1) Edge on LU, case 1: U2 R U R' R' F R F'
  • (LLLU2) Edge on LU, case 2: y U' L' U2 L L F' L' F
  • Edge on LL, touching:
  • (LLRU1) Edge on RU, side color not matching (R2, BR, rot): create a /R2/ case by using BR corner with R move, and U2, R U2' R' U' (R U R').
  • (LLRU2) Edge on RU, side color matching (LLBU2, BR): fall-back to case (LLBU1) using BR corner with U' then R, U' R U' R' U' y L' U' L (L F' L' F).
  • (LLFU1) Edge on FU, side color not matching (L2, FL, rot): create a /L2/ case by using BL corner with y L' move, and U2, y L' U2 L U (L' U' L) y'.
  • (LLFU2) Edge on FU, side color matching (LLLU1, FL): idem, fall-back using BL corner (with y U then L' ), y U L' U L U y' R U R' (R' F R F').

White sticker FRONT

  • Edge on 2LL:
Rb F2LF2Lcorrect.png
Case 1, edge correct
Can this case be be inserted from any angle without cube rotation?
  • (R1, BR) goal is to get a /R1/ using BR corner, U' R U' R' U2 R U' R'.
  • Faster, no y / y' , FR:
Rb F2LF2Lwrong.png
Case 2, edge wrong
  • (L2, BR) goal is to get a /L2/ using BR corner, U' R U R' U y L' U' L.
  • Faster, no y / y' , FL: y U2' L F' L' F U2' L' U' L y'
  • Edge on LL, non-adjacent
  • Case 1, same U color, edge BU (R1, BR): Goal is to get a /R1/ using BR corner, U' R U R' U2 R U' R'
Idem for edge LU (R1, BR): U' R U2 R' U2 R U' R'
  • Case 2, different U color, edge BU (L2, BR): Because U color are different, goal is to get a /L2/ case here using BR corner: y U L' U' L U' L' U' L (or U' R U' R' U y L' U' L).
For edge LU, this time we directly have a /L2/ (L2): y L' U' L
  • Edge on LL, adjacent on RU
  • Case 1, same U color (R1): we have directly a basic case /R1/, U R U' R'.
  • Case 2, different U color (L2, BR): so we want to get a /L2/, using BR corner: U' R U2 R' U y L' U' L.
  • Edge on LL, adjacent on FU
  • Case 1, same U color (R2, FL, rot): we use FL corner to get a /R2/ : y L' U L U2' y' R U R'
  • Case 2, different U color (R2, FL): we use FL corner to get a /L2/: y U L' U L U' L' U' L

White sticker RIGHT

  • Edge on 2LL 2LL:
Rb F2LR2Lcorrect.png
Case 1, edge correct
This case can actually be inserted from any angle without cube rotation.
  • (L1, FL) mirror of above, get a /L1/ using FL corner, and U then L' move: y U L' U L U2' L' U L y'.
  • Faster, no y / y' , FR: U R U R' U2 R U R'
  • Faster, no y / y' , BL: U L U L' U2' L U L'
  • Faster, no y / y' , FL: U L' U L U2' L' U L (alt using sledge: U L' U L L F' L' F, F with thumb)
  • Faster, no y / y' , BR: U R' U R U2' R' U R
Rb F2LR2Lwrong.png
Case 2, edge wrong
  • (R2, FL) mirror of above, get a /R2/ case using FL corner, and U then L' move: y U L' U' L y' U' R U R'
  • Faster, no y / y' : U2 R' F R F' U2 R U R'
  • Edge on LL, non-adjacent
  • Case 1, same U color, edge BU (L1, FL): Here the best is to solve FR then send it to BR y' U R' U' R U' U' R' U R y (alt: y' U R' U' R U' y F R' F' R or y U L' U' L U' L F' L' F y').
idem for edge LU (L1, FL): y' U R' U2 R U' U' R' U R y (alt: y U L' U2 L U' L F' L' F y').
  • Case 2, different U color, edge LU (R2, BR): we need to shift our edge by a single U move: U' R U R' U R U R'
For edge BU (R2): this time we directly get a /R2/: R U R'
  • Edge on LL, adjacent on RU
  • Case 1, same U color (L2, BR, rot): we get a /L2/ case using BR corner and R U' move, R U' R' U2 y L' U' L y'
  • Case 2, different U color (R2, BR): we get a /R2/ case using BR corner and U' R move, U' R U' R' U R U R'
  • Edge on LL, adjacent on FU
  • Case 1, same U color (L1): we directly have a basic case /L1/, L' U L
  • Case 2, different U color (R2, FL): so we want to get a /R2/ case. We can with FL corner, y' U R' U2 R y U' R U R' (or y U L' U2 L U' y' R U R')

Corner on 1L

White sticker DOWN

Rb F2LbelgeFR.png

Le Belge (front right)
  • Beginner solution U R U' R' y U' L' U L y'
  • Using inverse SH U R U' R' F R' F' R

Rb F2LbelgeFL.png

Le Belge (front left)
  • Beginner solution U' L' U L y' U R U' R' y
  • Using inverse SH U' L' U L F' L F L'
Le Belge (front right - alt)

Rb F2LbelgeRF.png

Le Belge (front left - alt)
  • Faster (no y / y') R U' R' U' R U' R' U R U R' (grip: LH F/B, index doing all U' and first U, RH U/D, index 2nd U) (R U' R' to create a known F2L case)
  • Faster (no y / y') U' R' F R F' R U R' (with a sledgehammer, 2nd U with LH index)
White sticker on FRONT / RIGHT face
  • First move edge on its color, then
    • If white sticker is on the SAME face → use a double sexy or sexyL.
    • If white sticker is on DIFFERENT face → use a TRUNCATED double sexy' or sexyL' , where first UP rotation is skipped.
  • Cases are identified by the visible colors on corner and lateral color on the edge. This is useful when solving the F2L in the wrong slot.

Sexysexy.png

col-white R-col

sexy sexy

(alt. U2 L' U L y' R U R')

SexyLsexyL.png

col-white F-col

y sexyL sexyL y'

(alt. U2 R U' R' y L' U' L y')

Rb sexypsexyp alt.png

white-col1-col2

R U' R sexy' (best grip, RH: front/back, index to prepare for U)

(alt. R U' R' R' F R F' or y L' U2 L y' R U2 R')

Rb sexyLpsexyLp alt.png

col2-col1-white

y L' U L sexyL' y'

(alt. R U R' U' F R' F' R)

More tricks

Tutoriel F2L avancés - Partie 1 (déconjugaison intelligente)
  • Déconjugaison intelligente
Tutoriel F2L avancés - Partie 2 (Insertions sous différents angles)
  • Avoid y2 moves, but solve the F2L cases as is (with empty slots in the back).
This is true for all "base" cases, both contiguous and not.
  • y and y' is ok. When choosing between both, favor the one that leads to R and U moves.
For instance, better do y' R' U R than y L' U L to insert a base case.
Tutoriel F2L avancés - Partie 3 (Utilisation des slots libres)
  • Use free slots
Tutoriel F2L avancés - Partie 4 (Eviter les rotations y et y')
  • Goal of this part: Avoid y and y' move whenever possible.
  • Introduce another commutator, the sledgehammer: R' F R F'
F' move must be done with the right thumb!
  • Case: R U' R y L' U2' L y', white sticker UP, FR corner.
Subcase FR. Use sledgehammer U' R' F R F' R U' R'
Subcase FL. Use left sledgehammer, or y' then subcase FR above.
Subcase BL. Use L U' L' y' L' U2 L. Or sledgehammer also possible, but with re-grip (B with right hand index).
Subcase BR. Usual solution is R' U R' F R F' R, but R' U R y U' R U' R' (U' while y) is also ok.
  • Case: U y L' U' L U' y' R U R'
Avoid cube rotation with sledgehammer: U2 R' F R F' U2 R U R'
  • Case: U y L' U L U2' L' U L y'
Can be inserted from any angle. Either pick contiguous base case or separated.
If corner in FR or BL: U R U R' U2 R U R' or U L U L' U2' L U L'.
If corner in FL or BR: U L' U L U2' L' U L (alt using sledge: U L' U L L F' L' F, F with thumb) or U R' U R U2' R' U R
  • Case: corner on D face
See my shortcuts above with sexy moves above.
  • Case: le Belge
When corner in FRD, and correct edge on UR, two solutions:
  • R U' R' U' R U' R' U R U R' (grip: LH F/B, index doing all U' and first U, RH U/D, index 2nd U) (R U' R' to create a known F2L case)
  • U' R' F R F' R U R' (with a sledgehammer)
Android - Fridrich Solver (Algorithms summary)
  • This app shows solutions for all F2L cases.
  • FAST: Use d and d' move instead of y' U or y U'. This happens extremely frequently, and is very useful to solve pair in any slot without turning the cube.