U perm

U Perms (Revisited)

Adventures in Cubing11 Comments
Slow-Motion videos of these algorithms are available here.

U Perms. Round 3. I sort of accidentally learned the U Perm (edge cycling) through the Beginner’s Method and its clunky final algorithm: F2 U(’) R’ L F2 R L’ U(’) F2. Then I started learning PLLs and wrote about the more efficient approaches I had found (now-stricken in the table below). When I did my foozled PLL time attack, that Ua was my fastest with Ub second. But those still involved a lot of moves, and Ub had a sort of clunky flow.

When I learned double M flicks, I started doing Ua with the new M/U algorithm. But I couldn’t get Ub figured out, with my hands mis-positioned for the U’ turns. Then I stumbled onto Anotine Cantin’s video on how to fingertrick Ub. A little awkward at first with the right index finger pulling left to right for U’, but it wound up being pretty easy after a little practice. Here’s my video showing both:

Once I got the finger-tricks figured out, these wound up having a really nice flow. And, in contrast to the older versions, there’s an elegant symmetry to the clockwise and counter-clockwise algorithms.

U PERM (Edge Cycle)

Ua PLL
Counter-Clockwise

M2 U M U2 M’ U M2

(R U’ R U) (R U) (R U’) (R’ U’ R2)

Ub PLL
Clockwise

M2 U’ M U2 M’ U’ M2

(R2 U) (R U R’ U’) (R’ U’) (R’ U R’)

Onward….

PLL edge cycles (U Perm)

Adventures in Cubing9 Comments
UPDATE: I’ve replaced this set of algs with M-slice versions.

Over the past couple months, I’ve tried to exorcise all remnants of the Beginner’s Method. F2L replaced the corner-first/edge-next approach a while ago, and several OLLs have made top-layer orientation a (generally) single-algorithm affair. But my PLLs were still a bit all over the place. I got to the two-look stage pretty easily (with no illusions about being able to one-look it for a while still), but realized that I was still using the Beginner’s Method algorithm for edge cycling — to wit, F2 U(’) R’ L F2 R L’ U(’) F2. Although I got freakishly quick at that algorithm, it required all sorts of awkward hand movements and lent itself to no finger tricks.

Since almost every one of my solves requires an edge cycle — with H and Z perms or the rare PLL skip as the lone exceptions — this bull-in-a-china-shop algorithm had to go. Enter the U perm:

U Perm (Edge Cycles)

Ua PLL(COUNTER-CLOCKWISE)

(R U’ R U) (R U)(R U’) (R’ U’ R2)

Ub PLL(CLOCKWISE)

(R2 U) (R U R’ U’)(R’ U’) (R’ U R’)

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