So, yeah, I’m still cross training, although I don’t expect to harvest any significant improvement for a while. In the meanwhile, I decided to learn a couple more OLLs that seem to crop up frequently — the single dot cases. The two cases (OLLs ##1 and 2 on the speedsolving.com wiki) are mathematically somewhat rare — with their probabilities at 1/108 and 1/54 respectively. That’s the equivalent of a 1-in-36 (or about a 2.8%) chance of having either of these cases arise during a solve. They seem to occur more frequently for me, probably just because not knowing how to one-look them made them more conspicuous.
I don’t usually post about each OLL or PLL I learn. But there seemed to be a dearth of tutorials on these two cases, with the few videos I found online lacking any technique focus or finger-trick explanations. Also, both of these OLLs seemed vulnerable to simplifying alternations to make them more accessible to beginners or novices. Here’s my short video tutorial:
Because OLL 2 is so much easier than OLL 1, I approached them in reverse order. The two cases look the same from the top, with only the center of the U face oriented. And both have a bar of three outward oriented U colors (with the edge and both corners pointing to the side), which bar should be placed facing left. If there is an opposite parallel bar of U colors on the right, it is OLL 1. If the there is a right-facing U color for the edge but the corners face front and back, it is OLL 2:
OLL #2 F (R U R’ U’) S (R U R’ U’ f’) |
OLL #1 R U (x’ U’ R U) (Lw’ R’) U’ (R’ F R F’) |
OLL 2
The first alg from here is the most common and is pretty straightforward. It’s basically two Sexy Moves, each with an F to setup and an F’ to complete. The only difference is that the first setup uses a single-layer F and the second set is a double-layer/wide F:
F (R U R’ U’) F’ Fw (R U R’ U’) Fw’
Because that F’ Fw is partially self-reversing (and clunky), I find it easier to simplify them into an S move (turn the layer sandwiched between F and B in the same direction as an F).
OLL 1
Per the wiki, there are two common algorithms for this case:
– (R U2) (R2′ F R F’ U2′) (R’ F R F’)
– R U B’ R B R2 U’ R’ F R F’
The first doesn’t lend itself to a rhythm (at least didn’t for me) and the second has those insufferable B moves. I was about to give up on this case altogether when I stumbled upon this good OLL video with the second algorithm at 3:10. His approach jettisons the second B by converting the R B R2 portion to Lw U Lw’ R’. That gave me the idea of dispensing with the first B’ as well. Since a B’ is the equivalent of x’ U’, and since the x’ would make the Lw’ just an R, it could all be reduced to this much simpler version, with no B turns: R U (x’ U’ R U) (Lw’ R’) U’ (R’ F R F’). Here is a bit more algebraically:
↓
R U B’ Lw U Lw’ R’ U’ R’F R F’
»
R U B’ Lw U Lw’ R’ U’ R’F R F’
↓
R U x’ U’ R U Lw’ R’ U’ R’ F R F’
»
R U (x’ U’ R U) (Lw’ R’) U’ (R’ F R F’)
I’ve only had a couple days to play with these, so far, but they’re both relatively fast and natural at this point. Two more OLLs in the quiver….
2 thoughts on “OLL Dot Cases (##1, 2)”