[Help Thread] Big Cubes Discussion

[EvilGnome6]

Hey guys, I'm pretty skrub at big cubes. I average 20 seconds on 3x3, 3 minutes on 5x5, and 12 minutes on 7x7. Is that proportionate at all? What do you guys average on 5 and 7? I use freeslice for both, but I feel like my 7x7 times are terrible and I don't know what to work on.

I think your 7x7 is lagging a bit but in my experience, the bigger the cube, the longer it takes to develop the dexterity to be fluid with it. Here are my singles and average from 2x2 - 7x7:

Single / Ao100:
2x2: 1.27 / 7.60
3x3: 18.69 / 27.33
4x4: 59.44 / 1:24.54
5x5: 2:14.05 / 2:46.26
6x6: 4:15/90 / 5:31.58
7x7: 6:54.69

 

[Ninja Storm]

Hey guys, I'm pretty skrub at big cubes. I average 20 seconds on 3x3, 3 minutes on 5x5, and 12 minutes on 7x7. Is that proportionate at all? What do you guys average on 5 and 7? I use freeslice for both, but I feel like my 7x7 times are terrible and I don't know what to work on.

3x3: 9.2ish
5x5: 1:18ish
7x7: sub4 somewhere lol

 

[Tgrede]

So I don't know if this is the correct place to ask this, I didn't want to start a whole new thread but I am not speedcubing big cubes, I collect and just like to learn how to solve. I recently got my 7x7 and can always get to the last 2 edges and I am wondering how to get my last 2 edges out of its current state, I can solve last 2 edges on my 4x4 and 5x5 but for some reason I cant use that knowledge for this 7x7. Are they completely different? or if I know one should I know the other, Also would knowledge of commutators/conjugates help with the edges I have? or is this something separate that I just have to know an algorithm for? I don't want to just know the algorithm, I want to actually know how to derive the algorithm and solve these last edges in an easy to understand way that will make it more intuitive the next time I come across this, any help will be appreciated.

 

[TheCoolMinxer]

Hey guys, I'm pretty skrub at big cubes. I average 20 seconds on 3x3, 3 minutes on 5x5, and 12 minutes on 7x7. Is that proportionate at all? What do you guys average on 5 and 7? I use freeslice for both, but I feel like my 7x7 times are terrible and I don't know what to work on.

3x3: 10.4ish
5x5: 1:25
6x6: 2:45
7x7: 4:25

 

[Tgrede]

How to derive my own algorithm to finish this cube

Hello, I have searched around and found about nothing about the edge parity issues on big cubes. I can find a ton of sources about how to fix it using a common algorithm but can anyone explain the theory behind the algorithm. for example I have my 7x7 solved to this point as you can see everything is correct, just the 2 inside outer layers on the blue and orange face are swapped. I don't want to just have an algorithm memorized I want to be able to derive my own solution to this. Is this a simple case of commutators and conjugates? because I haven't applied that to big cubes yet, only small so I am unsure how to apply commutators and conjugates here if necessary. Any help from anyone?

 

[PenguinsDontFly]

That should not be a case you get...you probably messed up your edge pairing during reduction...

 

[Tgrede]

well I can very easily just move the edges around to get them opposite of each other. my question is if I was edge paring how would I fix it. Here is the same case except now I just have to pair the edges which is the part I'm trying to figure out, I just figured it would be easier to see the case if I solved everything else, but yes I know I need to pair edges which is what I'm wondering how to figure out how to do.

 

[TDM]

well I can very easily just move the edges around to get them opposite of each other. my question is if I was edge paring how would I fix it. View attachment 5359 Here is the same case except now I just have to pair the edges which is the part I'm trying to figure out, I just figured it would be easier to see the case if I solved everything else, but yes I know I need to pair edges which is what I'm wondering how to figure out how to do.

From that position, try:
Uw' R U R' F R' F' R Uw // slice, flip edge, slice back
then
y' Uw R U R' F R' F' R Uw' // slice, flip edge, slice back (again)

I don't have a 7x7 to try it on but I'm fairly sure that will work.

 

[cmhardw]

How to derive my own algorithm to finish this cube.

Hello, I have searched around and found about nothing about the edge parity issues on big cubes. I can find a ton of sources about how to fix it using a common algorithm but can anyone explain the theory behind the algorithm. for example I have my 7x7 solved to this point View attachment 5358 as you can see everything is correct, just the 2 inside outer layers on the blue and orange face are swapped. I don't want to just have an algorithm memorized I want to be able to derive my own solution to this. Is this a simple case of commutators and conjugates? because I haven't applied that to big cubes yet, only small so I am unsure how to apply commutators and conjugates here if necessary. Any help from anyone?

Yes, this case can be easily solved with two commutators, possible even more efficiently if you choose the commutators in ways that cancel moves.

If Orange is the F face and blue the R face you can do something like:
F' f' to setup to an 8 move commutator.
U2 to interchange the two pieces
R d2 R' to place the lone piece into the slice
U2 to undo the interchange
R d2 R' to undo the place the lone piece to the slice
F f to undo the setup

Now the second commutator would be
R r to setup to an 8 move commutator
F' d2 F to insert the lone piece to the slice
U2 to interchange the pieces
F' d2 F to undo the placement
U2 to undo the interchange
R' r' to undo the setup

 

[Berd]

So I don't know if this is the correct place to ask this, I didn't want to start a whole new thread but I am not speedcubing big cubes, I collect and just like to learn how to solve. I recently got my 7x7 and can always get to the last 2 edges and I am wondering how to get my last 2 edges out of its current state, I can solve last 2 edges on my 4x4 and 5x5 but for some reason I cant use that knowledge for this 7x7. Are they completely different? or if I know one should I know the other, Also would knowledge of commutators/conjugates help with the edges I have? or is this something separate that I just have to know an algorithm for? View attachment 5356 I don't want to just know the algorithm, I want to actually know how to derive the algorithm and solve these last edges in an easy to understand way that will make it more intuitive the next time I come across this, any help will be appreciated.

You just need to pair them fully. Solve 1 full edge of the last two edges, the last one will either be solved or have parity. With parity do the 5x5 parity alg or the red bull alg.

 

[Tgrede]

Yes, this case can be easily solved with two commutators, possible even more efficiently if you choose the commutators in ways that cancel moves.

If Orange is the F face and blue the R face you can do something like:
F' f' to setup to an 8 move commutator.
U2 to interchange the two pieces
R d2 R' to place the lone piece into the slice
U2 to undo the interchange
R d2 R' to undo the place the lone piece to the slice
F f to undo the setup

Now the second commutator would be
R r to setup to an 8 move commutator
F' d2 F to insert the lone piece to the slice
U2 to interchange the pieces
F' d2 F to undo the placement
U2 to undo the interchange
R' r' to undo the setup

Thank you this actually helped a lot, I never was sure how to apply commutators and conjugates to bigger cubes but this definitely helps my understand more.

 

[NeilH]

Thanks for responding guys, I'll focus more on 7x7 for the next week and update you with my stats.

 

[Dene]

Thanks for responding guys, I'll focus more on 7x7 for the next week and update you with my stats.

I'd give it more than a week . Way back in the day I used to spend an hour or more on 6x6 and 7x7 pretty much every day. Took months to get down to decent times (although that was in the days of the first V-cubes).

 

[MennoniteCuber1]

Does anyone know how many cases there are for 4x4 l4e? Since there aren't many cases for l3e, I was just wondering how many for last 4.

 

[Mrsii]

My first timed 7x7 solve was 11:36. Is that terrible? How long did it take you guys to get sub-6 on a 7x7?
That's my goal til' the end of the year

 

[TDM]

My first timed 7x7 solve was 11:36. Is that terrible? How long did it take you guys to get sub-6 on a 7x7?
That's my goal til' the end of the year

Well mine was 13:44, so it's not bad at all! I've not done a second solve on one though

How fast you'll improve depends on how much you practise bigcubes - some people might find sub-6 easy to do in a few weeks, others might take a few months. But I think that even if you've not done bigcubes much, with a bit of practise every day or so you should be able to get sub-6 by the end of the year.

 

[guysensei1]

For someone who is around 2:30 for 6x6, what is the expected first 2 centers time? I usually aim to get mine sub-30
What about sub-4 7x7? I try to sub-1 minute by F2C.

 

[Berd]

For someone who is around 2:30 for 6x6, what is the expected first 2 centers time? I usually aim to get mine sub-30
What about sub-4 7x7? I try to sub-1 minute by F2C.

I average around 7 on 7x7 and nearly have sub 1 centers.

 

[guysensei1]

I average around 7 on 7x7 and nearly have sub 1 centers.

Uhh... Either your everything else is unusually slow or my everything else is unusually fast...

 

[Berd]

Uhh... Either your everything else is unusually slow or my everything else is unusually fast...

Yeah I'm just bad, ignore me.