Recognizing these PLLs

[pjk]

These are the last PLLs I need to learn. I can always recognize that I need to use one of these four, but to pick which one it is can be hard sometimes. What do you speedcubers use to recognize them? Thanks

 

[mgwallisa]

I look at the the two corner stickers of the same color on the one side and put those in the back. Looking for the 1x1x2 block (connected corner edge pair) will have a unique position for all four PLLs. It's a lot easier to recognize than all those arrows would have you to believe on the diagram.

 

[pjk]

I understand that it is easier. The way I have been doing it is lining up the 1x1x2 block, and that account for the blank spot, and then see whether it is clockwise or counter-clockwise. But that way is taking too long. I'll try putting the two same-colored stickers on the back. Thanks

 

[mgwallisa]

I just like them in the back because it puts the 1x1x2 block in the front. The right or left would be just as well for you maybe, depending on what you're comfortable with and the algortithms you like. But definately I would say it's pretty simple to recognize if you standardize the two corner stickers.

 

[gillesvdp]

Actually I use the block recognition instead of the corners recognition because then my image of the PLL is completely messed up (parity problem with the edges if you only consider the edges).

But that might be the reason why I am a bit slow at recognising it. I will try the corner recognition too.

Thanks

 

[cmhardw]

I understand that it is easier. The way I have been doing it is lining up the 1x1x2 block, and that account for the blank spot, and then see whether it is clockwise or counter-clockwise. But that way is taking too long. I'll try putting the two same-colored stickers on the back. Thanks

I use the block technique for that 1x1x2 block. It's really not that slow, just think about it like this. Find the 1x1x2 block. You don't have to line it up, just spot it. Then look at the side sticker of the edge that forms a 2x2x1 block with the 1x1x2 block. Then compare that to the side sticker of the edge in the 1x1x2 block. Knowing if those two stickers are opposite colors to eachother or not tells you which case you have.

All of my algs start with the 1x1x2 block at the front, which is why I do it that way, and personally those PLLs are among my favorite cases to see.

Just a thought,
Chris

 

[Scott]

The way I memorize it is, you always have the 1x1x2 block in the RFU position.

Then, if the FU edge is not solved, then that takes away two options. And if it is, then where does the FLU corner have to go. To either the BRU slot or the BLU slot. And the same goes for if the FU edge is solved, you just do it with the other 2 algorithms.

 

[raoul st. texas]

this is how i memorized these. 2 cases have a corner and the edge to the left and 2 cases have a corner and the edge to the right. That's easy to recognize.

now for deciding which of the 2 appropriate algs to use, look at the next logical corner piece and determine if the 2 colors (not including the top layer color) have a match on the L (for cases 1 & 4) or R (for cases 2&3) face.

For your cases you show here it would go (in order as they appear):
#1 LEFT - MATCH
#2 RIGHT - MATCH
#3 RIGHT - NO MATCH
#4 LEFT - NO MATCH

i hope this makes some bit of sense.