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In teamsolves, (not blindfold teamsolve, the one where people alternate turns) would M count as a single turn performed by one person, or should it be an R turn by one and then L' by the partner? I know this an unofficial event and there is no set rule, but is there a general consensus about it?
 
I just got a QJ 4x4. It locks up very much. It also pops frequently. First time a center piece fell off with a couple of other pieces, and i managed to fix it, but it has happened again, and i don't know how to place the center piece back.

Also, how can i stop the locking up and popping. I was told that QJ is a very decent cube.
 
Chapuunka, PM Jai about removing ball bearings. He took them out from his edison and got NAR with it.
 
Um, the speed of a PLL time attack has nothing to do with your actual 3x3 speed. I get like 45 and I'm sub 15. qqwref has a 35.xx on video and he's maybe a couple seconds faster than me (dunno for sure)

Yes, but I would think that there would be a general correlation between PLL speed and average speed. I would think that there would be a "If you average X, then most people would get Y for their PLL time attacks." Saying that a 40 second PLL time attack is normal for a 30 second average would make me think that Ben and I are huge outliers when it comes to PLL speed for our time. Both of us are below 30 seconds, yet neither of us are at 40 seconds for a PLL time attack, which is apparently what people as high as 30 seconds should be getting.

Somebody asked what time attacks they should be getting at 30 seconds. One person answered 40 seconds and another said 50.

You, Ben, and I are all sub 20 cubers, yet we all fall into the 40-50 second mark for time attacks. My point is that the two answerers are wrong because a 40-50 second time attack for 30 seconds seems to be unusual. All three of us are far below 30 seconds yet none of us are below what the "30 second norm" for a PLL time attack is.
 
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Average speeds also differ between F2L speed vs PLL speed, so if you for some reason have a lightning quick F2L but slow LL, your PLL attack would be slower than someone with a slower F2L but faster LL. I'd also think practicing PLL time attacks for the transition, etc. would affect it greatly.

So I, averaging low 20's, have ~60s PLL time attacks, but I don't practice them.
 
I'm just saying that it seems extreme to be suggesting that a 40-50 second time attack is necessary for a 30 second average. It was said by two people that 40 or 50 seconds is the time attack you should be getting at 30 seconds, but you too have shown that at a marginally, lower time many people are within or above 40-50 seconds.
 
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For algs, they're how many faces they use. So 2-gen algs are algs that only use <R,U> or <M,U>, etc. 3-Gen would be <R,U,F>, etc.

Well, Kirjava said that <M, U> isn't actually 2 gen.

My question: What is the actually definition of "_ gen"?
 
For algs, they're how many faces they use. So 2-gen algs are algs that only use <R,U> or <M,U>, etc. 3-Gen would be <R,U,F>, etc.

Well, Kirjava said that <M, U> isn't actually 2 gen.

My question: What is the actually definition of "_ gen"?

2 gen is 2 generator, so like, only two algs i thought?
 
I just got a QJ 4x4. It locks up very much. It also pops frequently. First time a center piece fell off with a couple of other pieces, and i managed to fix it, but it has happened again, and i don't know how to place the center piece back.

Also, how can i stop the locking up and popping. I was told that QJ is a very decent cube.

How does a center FALL OFF? It's hooked onto the core. That's something I gotta see :D

From what I see, you're prolly handling the QJ too rough. Be kind to it, and it shall reward you. And break it in(do a lot of solves to loosen it up) alogn with lubing it if you want to bring it to its full potential.
 
Two things I found:

http://akbar.marlboro.edu/~mahoney/courses/Spr00/rubik.html said:
How many positions are there in the subgroup generated by only the R and F moves? (the "2-face" subgroup)

http://akbar.marlboro.edu/~mahoney/courses/Spr00/rubik.html said:
Group Generators
Given a group G (and in this section, we’ll almost always use Rubik’s group R as our group),
then if S ⊂ G is any subset of the group, then the subgroup H generated by S is the smallest
subgroup of G that contains all the elements of S.
Surely such a subgroup exists. If any collection of different subgroups contain all the members
of S, then their intersection (which is also guaranteed to be a subgroup) also contains all the elements of S and is contained in all of them. The group G is a subgroup of itself, so there is at
least one group in that intersection.
Intuitively, the subgroup generated by S is the collection of all the elements you can get to
by repeatedly multiplying members of S or their inverses together. In the case of R, it’s the set
of all positions you can arrive at, starting with the jumbled cube and applying only that subset of
moves in any order.
For example, the subgroup of R generated by { F } contains four members. If you’re only
allowed to turn the right face, you can only get to four different cube configurations. The subgroup
generated by { FF } is even smaller: two positions. In other words, if you’re only allowed
to make half-turns of one face, there are only two possible positions you can achieve starting
from solved.
Obviously, the group generated by { F, B, R, L, U, D } is the entire group R—just a small
number of generators can generate a huge group. We are interested, of course, in subgroups that
fall between the extremes mentioned in this and the previous paragraph.

The first one only talks about "2-face" subgroup (which would obviosly exclude slices), and the second one does not mention slices... I'm stuck. Does "2-gen" actually refer to slice moves?
 
In terms of speedcubing, I think slices could be part of 2-gen stuff, but in more strict theory, it wouldn't. But that's just practicality; how many of use would say the (normal 2H) H-Perm isn't 2-gen?
 
In terms of speedcubing, I think slices could be part of 2-gen stuff, but in more strict theory, it wouldn't. But that's just practicality; how many of use would say the (normal 2H) H-Perm isn't 2-gen?

The Wiki does say that it refers to "sides or slices of the puzzle", so I'm guessing that while "2-face" refers to only sides, "2-gen" does in fact refer to slices as well.
 
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