# [UWR] 128x128x128 solve



## qqwref (Nov 4, 2014)

Tomorrow I'm planning to start a 128x128x128 cube solve, which will be a world record for the largest cube ever completed. I estimate it will take about 40 hours, which I will NOT do in one sitting, but in multiple sessions over the course of a few weeks. I will use pretty much the same method as the 111x111x111 solve I did in 2013, just with some minor improvements.

I'm planning to livestream it a http://www.twitch.tv/qqwref. I won't have a mic, since I don't generally talk much when doing stuff like this, but you're all welcome to pop in and say hi in the chat  I'll also post picture updates in this thread to show how it's going.


EDIT: It's done! Lots of info in this post: https://www.speedsolving.com/forum/...8-solve-soon&p=1034593&viewfull=1#post1034593


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## biscuit (Nov 4, 2014)

wow... hope to be able to pop in some time! GL


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## IRNjuggle28 (Nov 4, 2014)

Mmmm. You're nuts. Find some good music, or something to listen to during all that. ^_^


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## donal56 (Nov 4, 2014)

Which program do you use to emulate that cube ? Wow


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## JasonDL13 (Nov 4, 2014)

I will defiantly come and watch for a bit.

However: It would be a good idea to have a mic so you can talk to people in the chat.

Good luck.


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## blade740 (Nov 4, 2014)

What a badass.


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## Randomno (Nov 4, 2014)

JasonDL13 said:


> I will defiantly come and watch for a bit.
> 
> However: It would be a good idea to have a mic so you can talk to people in the chat.
> 
> Good luck.



http://www.d-e-f-i-n-i-t-e-l-y.com/

Can you try the cube in a cube^128?


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## TDM (Nov 4, 2014)

Good luck!


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## szalejot (Nov 4, 2014)

This is crazy.

Good luck. Hope to have not so many parities


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## megaminxwin (Nov 4, 2014)

You're stupid. I love it. Good luck!


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## Coolster01 (Nov 4, 2014)

Randomno said:


> http://www.d-e-f-i-n-i-t-e-l-y.com/
> 
> Can you try the cube in a cube^128?



Looool that website. 

I hope you get double parity ;D


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## guysensei1 (Nov 4, 2014)

Coolster01 said:


> Looool that website.
> 
> I hope you get double parity ;D



Why not triple parity? 

Although it wouldn't be that hard to just execute the alg right?


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## Randomno (Nov 4, 2014)

Coolster01 said:


> Looool that website.



Found it several years ago. Can be pretty useful.


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## cmhardw (Nov 4, 2014)

Go Michael! This is exciting, I plan to follow along with the live stream


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## Robert-Y (Nov 4, 2014)

Good luck!

Would it be possible to see some statistics during the solve? e.g. time for first half of white centres


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## Randomno (Nov 4, 2014)

Gonna be funny how unproportional the sections will be...

Centers: 10 hours
Edges: 29.9 hours
3x3: Few minutes max.


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## AlexMaass (Nov 4, 2014)

Randomno said:


> Gonna be funny how unproportional the sections will be...
> 
> Centers: 10 hours
> Edges: 29.9 hours
> 3x3: Few minutes max.


Parity: 5 minutes


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## Randomno (Nov 4, 2014)

AlexMaass said:


> Parity: 5 minutes



That as well I guess...


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## Rocky0701 (Nov 4, 2014)

Wow! I didn't know that you have done a 111x111 solve either. This is completely insane to me! Good luck, and be careful not to hit the reset button.


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## hawkmp4 (Nov 4, 2014)

Still with the computer puzzles, huh? Some things never change. I'm excited for the streams.


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## qqwref (Nov 4, 2014)

First part later tonight (let's say 7pm Eastern). I'm starting with edges, which is roughly an hour, and then I'll move onto clearing the white center.



donal56 said:


> Which program do you use to emulate that cube ? Wow


IsoCubeSim



JasonDL13 said:


> However: It would be a good idea to have a mic so you can talk to people in the chat.


I can type stuff, it doesn't waste much time (and I don't usually get that many people in chat when I'm streaming stuff ). And since I don't talk often normally, you'd just be hearing clicking most of the time. Probably better to just let people listen to whatever they want.



Randomno said:


> Can you try the cube in a cube^128?


If you mean a super-supercube, that would take about 21.5 times as long as this one (and there's no sim that can handle anything even remotely close to that anyway). If you just mean the pretty pattern, I could do this one and a few others at the end, sure 



szalejot said:


> Good luck. Hope to have not so many parities


Hehe, don't worry, I do all the OLL parities at once  The algorithm I use is r2 U2 r' U2 r' [flip UB] r' [unflip UB].



Robert-Y said:


> Would it be possible to see some statistics during the solve? e.g. time for first half of white centres


Sure, I'll keep track of the time at each major section.



Randomno said:


> Gonna be funny how unproportional the sections will be...
> 
> Centers: 10 hours
> Edges: 29.9 hours
> 3x3: Few minutes max.


More like:
Edges: 1 hour
Centers: 39 hours


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## JasonDL13 (Nov 4, 2014)

Randomno said:


> http://www.d-e-f-i-n-i-t-e-l-y.com/



I blame my auto correct in chrome http://prntscr.com/534kty


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## Randomno (Nov 5, 2014)

JasonDL13 said:


> I blame my auto correct in chrome http://prntscr.com/534kty



That's defenitely wrong.


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## atouchofgeek (Nov 5, 2014)

That's some determination, atleast you'll be able to say you did it when it's over!


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## ComputerGuy365 (Nov 5, 2014)

Good luck mate.


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## AlGoreRhythm (Nov 5, 2014)

> > Quote Originally Posted by JasonDL13
> > I blame my auto correct in chrome http://prntscr.com/534kty
> 
> 
> That's *defenitely* wrong.



Did you spell that wrong as a joke?


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## qqwref (Nov 5, 2014)

Finished edges and 3x3x3 at 1:21:58.421 seconds, in 2951 moves. That's 0.600 moves per second, 1.941 moves per piece, and 3.236 seconds per piece. (The seconds per piece will be much lower later.)






First session done, so far 2:33:22.515 and 7415 moves. About a third of the white center is cleared.


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## Deathranger999 (Nov 5, 2014)

Great start Michael! Looking awesome so far.


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## IRNjuggle28 (Nov 5, 2014)

Randomno said:


> Gonna be funny how unproportional the sections will be...
> 
> Centers: 10 hours
> Edges: 29.9 hours
> 3x3: Few minutes max.



The centers will take way longer than the edges.

EDIT: should've read thread before posting


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## Rocky0701 (Nov 5, 2014)

AlGoreRhythm said:


> Did you spell that wrong as a joke?


Lol he defiantly did.



qqwref said:


> Finished edges and 3x3x3 at 1:21:58.421 seconds, in 2951 moves. That's 0.600 moves per second, 1.941 moves per piece, and 3.236 seconds per piece. (The seconds per piece will be much lower later.)
> http://i.imgur.com/9lbYJhD.jpg
> 
> First session done, so far 2:33:22.515 and 7415 moves. About a third of the white center is cleared.
> http://i.imgur.com/I6lxTaV.jpg


How do you tell each layer apart? It looks impossible to see. Are you able to zoom in on the program?


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## szalejot (Nov 5, 2014)

qqwref said:


> Finished edges and 3x3x3



Do you start with edges and 3x3?
What kind of method is that?


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## irontwig (Nov 5, 2014)

szalejot said:


> Do you start with edges and 3x3?
> What kind of method is that?



(A type of) cage method.


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## Randomno (Nov 5, 2014)

qqwref said:


> Finished edges and 3x3x3 at 1:21:58.421 seconds, in 2951 moves. That's 0.600 moves per second, 1.941 moves per piece, and 3.236 seconds per piece. (The seconds per piece will be much lower later.)
> http://i.imgur.com/9lbYJhD.jpg
> 
> First session done, so far 2:33:22.515 and 7415 moves. About a third of the white center is cleared.
> http://i.imgur.com/I6lxTaV.jpg



I think I've seen an image like that.

Oh yeah, a compressed JPEG.


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## qqwref (Nov 6, 2014)

For some reason there were a few null characters in my save and it was breaking when I tried to load the save again (a disturbing amount of the cube was showing as solved because it just stopped reading the stickers partway through). I managed to fix that, and also improved the saving part so it doesn't take forever. Download updated version here. Dunno why this problem never showed up before, but I could have fixed the save thing at any time, I just hadn't looked at the program since mid 2013.

I'm going to be starting the second stream for real soon.



Rocky0701 said:


> How do you tell each layer apart? It looks impossible to see. Are you able to zoom in on the program?


Yeah, when I do my solve I'm zoomed in a lot. The zoom out is to make it easier for anyone watching the topic to see progress.



szalejot said:


> Do you start with edges and 3x3?
> What kind of method is that?


A cage method  It's actually quite optimized and for very large cubes I think it's significantly faster than reduction, and more efficient too unless you are incredible at finding pieces. The description in the 111x111x111 topic is pretty close to what I use, although I have changed some details since then.


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## brian724080 (Nov 6, 2014)

How big is your screen?


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## qqwref (Nov 6, 2014)

After the second session, I have finished clearing the white center. Total time 4:33:48.109, and 16367 moves. That means that since edges+3x3x3 I have done moves at 1.166 moves/second. Clearing solves about 63.5% of the white centers (and 1/6 are solved already) so I solved about 7439 additional centers (don't know the exact number) at a rate of about 1.803 moves per piece or about 1.547 seconds per piece.







brian724080 said:


> How big is your screen?


Overall 1680x1050... but I don't fill it all with the cube. I also have stuff like twitch chat open. Having it fullscreen wouldn't save much time since I spend most of the time looking at a single column anyway.


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## brian724080 (Nov 6, 2014)

qqwref said:


> Overall 1680x1050... but I don't fill it all with the cube. I also have stuff like twitch chat open. Having it fullscreen wouldn't save much time since I spend most of the time looking at a single column anyway.



I see, but don't you find it annoying that you can only see so much of the cube?


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## mark49152 (Nov 6, 2014)

Just curious, but at what size do you think it becomes more efficient to use the cage approach than centres-first reduction? If you were solving a physical 11x11 or 8x8, what would you use?


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## qqwref (Nov 7, 2014)

I'm dumb so no progress today. Oh well.



brian724080 said:


> I see, but don't you find it annoying that you can only see so much of the cube?


With this method, it doesn't hurt. It also keeps down lag.



mark49152 said:


> Just curious, but at what size do you think it becomes more efficient to use the cage approach than centres-first reduction? If you were solving a physical 11x11 or 8x8, what would you use?


It's hard to tell and it definitely depends on how good someone is on each method. Comparing cage on Iso vs reduction on Iso, cage is faster starting on the 10x10x10; comparing cage on Iso vs reduction on qcube, cage is faster starting on the 12x12x12. For physical cubes I think you'd need a really really big cube for cage to be worthwhile because slice turns are such a pain.


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## qqwref (Nov 8, 2014)

White center solved! Yay!

Total time 7:51:14.623, and 39775 moves. Since clearing I have done moves at 1.976 moves/second. I don't know exactly how many white center pieces were solved since then, but it should be about 5791. That gives me a solving rate of about 4.042 moves per piece (as expected since almost all the new pieces were solved with 4-move commutators) or about 2.046 seconds per piece.


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## Artic (Nov 8, 2014)

You sir, are one sick puppy  Seriously thought, that's amazing.


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## qqwref (Nov 9, 2014)

I'm now a little over halfway done clearing the yellow center. When the clearing is done, I expect about 71.8% of the yellow centers will be solved. In this session I did about 1.403 moves per second.


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## IRNjuggle28 (Nov 9, 2014)

qqwref said:


> stuff


...the E layer edges aren't solved anymore?


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## qqwref (Nov 9, 2014)

They're one ATM move from solved (that is, turn every u slice by some amount). That is supposed to happen during clearing, and I'll fix them very quickly later. It's like what happens to the centers during freeslice edges.


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## qqwref (Nov 11, 2014)

Finished clearing the yellow center, at 11:00:36.467 and 56233 moves. Since solving the white center, I estimate that I have solved an additional 8228 centers (the yellow center should be about 71.8% done). So the yellow center clearing stage involved 1.449 moves/second, about 1.381 seconds/piece, and about 2.000 moves/piece.





And this is how far I've gotten in ~50 minutes since then, with the face opposite white cleared of yellow pieces, and working on the other three...


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## IRNjuggle28 (Nov 11, 2014)

Great progress! Wow.


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## Artic (Nov 11, 2014)

This is insane heheh


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## cmhardw (Nov 12, 2014)

Very cool! I love the updates and pictures!


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## qqwref (Nov 13, 2014)

Thanks Chris, glad the stuff I'm posting is interesting 


The yellow center is now done - two down, four to go. The time is now at 13:42:01.983, with 74087 moves. Since I finished clearing yellow, I've solved about 4473 more centers. Thus the final yellow solving involved 1.843 moves/second, about 2.165 seconds/piece, and about 3.992 moves/piece (again, 4-move commutators).





In total, the yellow center took me about 5 hours 51 minutes and 34312 moves. The whole center was 1.630 moves/second, about 1.657 seconds/piece, and about 2.702 moves/piece. If I can solve the 3rd, 4th, and 5th centers in the same time - the 6th doesn't need to be solved - I'll finish at 31 hours 15 minutes and 177023 moves. That's quite a bit ahead of my initial estimate!


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## biscuit (Nov 13, 2014)

Ok so I blame chrome to... Or my own incompetence. Spelling never has been my strong suit. Also that is amazing! This is what everyone should do.


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## qqwref (Nov 14, 2014)

Orange center clearing is done! This is the last real clearing step, which means that from now on I'll be finishing each center in one step. About 60.7% of this center should be solved now (with about 25% of it solved initially), so in this part I solved about 5670 centers. This step was done at 1.944 moves/second, about 2.080 moves/piece, and about 1.070 seconds/piece.


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## qqwref (Nov 15, 2014)

Here's my progress today. I'm at 17:48:02.734 with 102944 moves, so since last time I did moves at 1.962 moves/second. The scrambled center in the image is the last one I have to move lots of oranges from, and then it's just catching the remaining stragglers and orange will be finished.


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## Owen (Nov 15, 2014)

qq, you're an unsung hero of our time.


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## Bindedsa (Nov 15, 2014)

Owen said:


> qq, you're an unsung hero of our time.



Unsung? People are always talking about how awesome he is.


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## stoic (Nov 15, 2014)

Incredible stuff. Keep the updates coming!


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## Owen (Nov 15, 2014)

Bindedsa said:


> Unsung? People are always talking about how awesome he is.



Not outside the cubing community.


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## qqwref (Nov 16, 2014)

Thanks guys 

The orange center is done, at 18:45:51.625 and 109971 moves. Since I finished clearing, I've solved about 6237 centers, which means I did that segment with 1.981 moves/second, about 3.862 moves/piece, and about 1.950 seconds/piece.





I also started work on the blue center. There's no clearing stage here - I'm bringing all the blue pieces from both F and B up to U, one column at a time. So I'm about 20-25% done with this part. Since doing the orange center I've been going at 1.478 moves/second.


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## mns112 (Nov 16, 2014)

How do you even see the pieces? Do you Zoom in or use a very large screen?
Amazing man!!


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## qqwref (Nov 16, 2014)

I zoom in a lot when actually solving, and then I zoom out to take pictures


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## Arman2405 (Nov 16, 2014)

WOW!!!! Good luck


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## qqwref (Nov 17, 2014)

Still working on the blue center  I'm now at 21:49:52.452 and 127141 moves. I did this part at 1.596 moves/second.






EDIT: Something weird happened with the movecount (it wasn't supposed to be 138620). I loaded the save and got a new screenshot. I thought 3.191 moves/second was unrealistic!


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## mns112 (Nov 17, 2014)

You should rename this thread to [WARNING: Amazing stuff is going on in here]


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## qqwref (Nov 18, 2014)

I'm now done with the blue center! The time is 23:33:13.796, and I've done 137779 moves. This session was done at 1.715 moves/second. After finishing orange, about 1/3 of blue was already solved, so I solved about 10584 centers. That means that I did the blue center stage at 1.613 moves/second, about 2.627 moves/piece, and about 1.629 seconds/piece.


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## TraciAG (Nov 18, 2014)

how many breaks have you taken so far?


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## IRNjuggle28 (Nov 18, 2014)

I have a feeling this UWR will stand for quite a while...

Out of curiosity, what made you choose 128?


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## guysensei1 (Nov 18, 2014)

IRNjuggle28 said:


> I have a feeling this UWR will stand for quite a while...
> 
> Out of curiosity, what made you choose 128?



2^7?


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## qqwref (Nov 18, 2014)

TraciAG said:


> how many breaks have you taken so far?


I've been doing it in roughly-2-hour chunks once a day (with some days skipped due to technical difficulties or a competition). I couldn't do something like this in one sitting, I would worry about repetitive motion injury.



IRNjuggle28 said:


> I have a feeling this UWR will stand for quite a while...
> 
> Out of curiosity, what made you choose 128?


We'll have to see, the 111 only stood for like 6 months 

I wanted to do an even cube this time (since they're easier with my method), and it had to be above the 121, but not too big. 128 seemed like a nice number since it's not too much higher and (as guysensei1 said) it's also a power of 2.


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## mns112 (Nov 18, 2014)

At the start you said you did something called clearing.
What was that?


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## qqwref (Nov 19, 2014)

mns112: Clearing is basically a step that has the goal of quickly solving a large portion of the center in relatively few moves. It does that by only solving centers that are in particular positions on the cube. Solving the center in two steps (clearing and then any pieces not solved yet) turns out to be significantly faster and more efficient than just solving all the pieces directly with commutators.

I'm now roughly 2/3 through the last 2 centers, at 25:32:13.765 and 151220 moves. I did this part at about 1.883 moves/second. There should be about an hour left at this point, so I should be done tomorrow (and then I might show off a pretty pattern or two ).


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## Cube Is Life (Nov 19, 2014)

You should do a tutorial for extra big cubes.


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## IRNjuggle28 (Nov 19, 2014)

Cube Is Life said:


> You should do a tutorial for extra big cubes.


How about just a walkthrough solve with the cage method you use (I want to name it the "qqage method.  "qqage" is pronounced "cage") on an 8x8 computer cube?


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## szalejot (Nov 19, 2014)

IRNjuggle28 said:


> How about just a walkthrough solve with the cage method you use (I want to name it the "qqage method.  "qqage" is pronounced "cage") on an 8x8 computer cube?



That would be great


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## qqwref (Nov 20, 2014)

I'm done!  The final result was 26:25:18.515 and 157318 moves. I'll post some more detailed statistics later but for now here's what I got...

The last two centers were done in just under 3 hours and 19539 moves. About 7938 green centers needed to be solved, so I was solving green at a rate of 2.039 moves/second, about 2.459 moves/piece, and about 1.206 seconds/piece. Of course that is only taking into account the unsolved green centers, so if you count all 31752 green and red center pieces, you get much better numbers 





I also made a cube in cube pattern for Randomno 


Spoiler


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## Thatoneguy2 (Nov 20, 2014)

Wow congrats! Can't believe you have that much determination to be able to finish that, it's really impressive.


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## Stefan (Nov 20, 2014)

Congrats. Now finally update the thread title 

And next time sub-24h? What's the record for largest cube solved on one day?


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## qqwref (Nov 22, 2014)

Imgur album of progress: http://imgur.com/a/izVLF

Youtube playlist of the entire solve: https://www.youtube.com/playlist?list=PLEeuqKEdptAM0DpOuhWpsi6HRkrTRcHHc

Updated historical WR list:


Spoiler



2x2x2 - January 12, 2000, by David Barr, in 35.600
3x3x3 - January 12, 2000, by David Barr, in 1:23.600
4x4x4 - January 12, 2000, by David Barr, in 5:52.460
5x5x5 - January 12, 2000, by David Barr, in 9:20.180
6x6x6 - January 13, 2000, by David Barr, in 16:42.830
7x7x7 - January 21, 2000, by David Barr, in 23:33.450
11x11x11 - March 12, 2000, by David Barr, in 1:20:15.566
11x11x11 - June 12, 2000, by Chris Hardwick, in 56:32.298
11x11x11 - February 20, 2001, by fl, in 5:24:40.242
11x11x11 - April 11, 2001, by fl, in 6:57:35.728
11x11x11 - May 25, 2001, by fl, in 2:23:04.975
11x11x11 - May 31, 2001, by vfr, in 1:36:03.768
20x20x20 - June 12, 2001, by Chris Hardwick, in 4:24:54 (solving time) or 8:13:56 (total time)
20x20x20 - March 16, 2002, by Richard Carr, in 3:53:39.573
20x20x20 - June 25, 2002, by Richard Carr, in 3:05:27.722
20x20x20 - September 7, 2002, by Richard Carr, in 2:46:48.822
21x21x21 - October 28, 2002, by Grant Tregay, in 72:38:11.378
31x31x31 - January 1, 2003, by Richard Carr, in 7:43:15.493
35x35x35 - October 1, 2003, by Joe Allen, in 103:26:10.140
39x39x39 - October 8, 2003, by Joe Allen, in 113:48:13.052
40x40x40 - February 17, 2004, by Chris Moyer-Grice, in 23:35:xx (solving time)
55x55x55 - March 18, 2004, by Joe Allen, in 23:00:24 (solving time)
100x100x100 - December 20, 2008, by Ravi Fernando and Peter Greenwood, in 820:13:11.220
111x111x111 - May 19, 2013, by Michael Gottlieb, in 29:51:02.641 (solving time) or 246:48:xx (total time)
121x121x121 - September 30, 2013, by Adrian Acosta, in 89:02:26.601 (solving time) or ~2106 hours (total time)
*128x128x128 - November 19, 2014, by Michael Gottlieb, in 26:25:18.515 (solving time) or 361:36:xx (total time)*



Whole-cube statistics:


Spoiler



- Total solve time: 26:25:18.515, or 95,118.515 seconds
- Total moves: 157,318
- Number of pieces: 96,776
- Number of positions: 7.8 * 10^63054
- Seconds per piece: 0.983 (compared to 1.480 for the 111)
- Moves per piece: 1.626 (compared to 2.781 for the 111)
- Moves per second: 1.654 (compared to 1.878 for the 111)
- Real time spent: about 15 days 1 hour 36 minutes (from 7:09 PM on the 4th, until 8:45 PM on the 19th)
- Percent of time spent working: 7.3%



Stage by stage statistics:


Spoiler



Note that for "pieces solved" here I mean the number of new pieces I deliberately solved in this stage. There are many pieces which accidentally solve themselves - for instance, the entire sixth center, or about 1/6th of all centers which are solved after edges. I didn't include those here because just keeping track of the pieces I solved on purpose gives more useful numbers for moves/piece and time/piece.


```
Stage           Time          Moves   Pieces  mov/sec mov/pc  sec/pc
Edges + 3x3x3   1:21:58.421   2951     1520   0.600   1.941   3.236
1st Clearing    3:11:49.688   13416   ~7439   1.166   1.803   1.547
1st Finishing   3:17:26.514   23408   ~5791   1.976   4.042   2.046
2nd Clearing    3:09:21.844   16458   ~8228   1.449   2.000   1.381
2nd Finishing   2:41:25.516   17854   ~4473   1.843   3.992   2.165
3rd Clearing    1:41:08.375   11796   ~5670   1.944   2.080   1.070
3rd Finishing   3:22:41.267   24088   ~6237   1.980   3.862   1.950
4th             4:47:22.171   27808   ~10584  1.613   2.627   1.629
5th & 6th       2:52:04.719   19539   ~7938   1.892   2.461   1.301
```

And if we combine the clearing+finishing stages to get a better sense of how long each center took:


```
Stage           Time          Moves   Pieces  mov/sec mov/pc  sec/pc
Edges + 3x3x3   1:21:58.421   2951     1520   0.600   1.941   3.236
1st             6:29:16.202   36824   ~13230  1.577   2.783   1.765
2nd             5:50:47.360   34312   ~12701  1.630   2.702   1.657
3rd             5:03:47.642   35884   ~11907  1.968   3.014   1.531
4th             4:47:22.171   27808   ~10584  1.613   2.627   1.629
5th & 6th       2:52:04.719   19539   ~7938   1.892   2.461   1.301
```




The method I used:


Spoiler



Anything underlined is new since the 111x111x111. The rest is the same.

First, some basics. I solved most faces in two steps: "clearing" and finishing up. The idea of clearing a face is to solve as many pieces as possible as quickly as possible. After that step, which typically solves 50% or more of the face, I can go through the longer step of putting each of the remaining pieces of that color into the center, one at a time or in blocks. As for notation, I'll be using something like SiGN (xR means turn the xth layer on the R face, or the first layer if x is absent), except that I'll also be using lowercase p and q as variables to better describe classes of commutators.

1) Solve the edges. I do edges first for large computer cubes because reduction (centers first) scales badly, and because having solved edges actually lets me use them to keep track what part of the puzzle I'm working on. A lot of the time I do a pR' move or something to start working on a row of one center, and the incorrect edge reminds me which row it is. With so many layers it's impossible to do it by counting or visual inspection alone. Anyway, for the first 9 edges I did basically the same thing as with other cubes. For the last three edges I used moves like pR U2 pR' (for the 10th edge only), pR2 U2 pR U2 pR2, and pR' F U' R F' U pR. Instead of solving one orbit at a time like on my keyboard solves, I went for an edge at a time and solved pieces in the same position in groups. For instance on the last 3 edges there are only 6 possible positions for each piece, so with 126 pieces in each edge there are a lot of pieces in the same position which can be solved in the same way, all at once, by replacing a pR move with a whole bunch of slice moves along the same layer. This took about an hour and twenty minutes in total.

2) Clean the first center. I used white. Hold the white face on U, and then for each row (perpendicular to the F face), we do something like this: move white centers out of the way on the corresponding row on F using pU moves, then qR', then solve as many white centers into that layer as possible using only pU-axis moves, then qR. By "solve as many white centers ... as possible" I mean I basically look at that row on R, B, and L, and for every white center I see, move that layer the right amount. Note that these rows are vertical, which is something I did because of the way Iso is set up (when zoomed in, it's easy to scroll through a vertical row on F or R using just the up/down arrow keys). You could do any of this from a different angle if you wanted. A typical layer might be something like (2U 4U 7U ...) 3R' y (3U 6U 8U ...) y (U2 4U2 8U2 ...) y (2U' 3U' 4U' ...) y 3R. Each center on white corresponds to 5 stickers, and a white center on any of those 5 stickers means the center gets solved. About 63.5% of the center ends up solved.

3) Finish the first center. Now I can hold the center on F and look at R. If I see a white center anywhere, I can solve it using pF qU' pF' qU. Four-move commutators are fast! However, I can't just do that randomly, but instead, I have to do it so that the center moves into a place on the white center that didn't have a solved center already. I often do y' y to see what pieces can be moved into holes in the white center, and a lot of pieces can be solved this way before I need to rotate the white center and check again. You'll see this type of checking often as I continue. Note that this requires centers to be adjacent, and since we're solving from all five, we have to swap two adjacent centers. On the 4x4x4 the algorithm for this is r U2 r' l' U2 l, which you then have to properly undo later.

4) Clear the second center. I used yellow. This is the same idea as the first center - hold yellow on U (so, white on D) and proceed row by row. However, instead of using pR' moves to move a row onto the F face, I used pR U2 pR' moves. This does solve the layers in a different order, but that's okay. For the middle layer I used U pR U' pR'. Each center on yellow again corresponds to 5 stickers (any yellow piece in one of those 5 places means that piece gets solved), and about 71.8% of the center ends up solved after this.

5) Finish the second center. Again I swap yellow with another center, so I can hold yellow on F, white on U, and the solved center on R. The commutator this time is pF2 qU' pF2 qU (or pF2 qU pF2 qU' for the mirror). Since I can't just do x rotations and keep going, I have to do some extra center swaps to bring each of the four non-white/yellow centers into the right place. There was also plenty of y' y to check if there's room to put a piece.

6) Clear the third center. I used orange (for visibility). Place orange on U and white/yellow on L/R. Now we can do pU2 moves but not pU moves. So I do something like the white center clearing, where I do pU2 moves to move orange centers out of the way, then a qR' move to bring the row down, then do more pU2 moves to solve as many orange centers as possible, then a qR move. A typical row clear might look something like (2U2 4U2 7U2 ...) 3R' y2 (2U2 3U2 4U2 ...) y2 3R. Each center on orange corresponds to only 3 stickers, solving about 60.7% of the center.

7) Solve the third center. This is just like what I do on yellow, with the pF2 qU' pF2 qU moves, since they keep U and D solved, and again I use plenty of y' y moves. In fact, there are fewer center swaps than last time, since the D center can stay where it is.

8) Solve the fourth center. As a general rule you want this to be adjacent to the third center, so I chose blue. However, I want to set up the blue center opposite orange for the algorithms I use, so I do a center swap. Now the idea is to move all blue centers out of both F and B, one column at a time. I use pU2 moves to move as many blue centers as possible off F, then qR U2 qR' to move a column of the blue center down to F, and then more pU2 moves to bring as many blue centers onto that colun as possible. Then I undo the qR U2 qR' to put the blue center column back, and do a U turn. This is a lot like the clearing stages, except that for each column we repeat the process as necessary (at most 4 times, for the 4 possible orientations of the U center) to solve all blue centers on that column. Then we just move onto the next column, and so on until all blue centers are on U.

9) Solve the last two centers. Swap the fourth center back into place first, so the two centers are adjacent. Place blue on F, red on U, and green on B; we again want to solve one center (green) column by column. Do a qR' y2 to bring a row down, and then use a pU2 move on all the red centers in that column, and then a y2 again. Now you have a lot of unsolved rows with red pieces in that column. Do qR U qR', and if you see any green centers in that column on one of those unsolved rows, solve it with a pU2. Repeat the same thing two more times, and almost all of those rows should be solved. The remaining rows are ones where no amount of qR U qR' will put a green center there. There are a few ways to fix this; for this solve I did y2 (U2 qR U2 qR'), then pU2 moves to solve all the rows at once, then (qR U2 qR' U2) y2. Then just do a qR to finish that column, and you can start the next column by bringing a row down. Once all the columns are done, everything is solved and you just have to fix the U face.





Stefan said:


> And next time sub-24h? What's the record for largest cube solved on one day?


As far as I know, the record for solving within one real day is 40x40x40 (by Joe Allen (in 8 hours in 2006) and me (in 2.6 hours in 2013)) and the record for solving in <= 24 hours of solving time is 55x55x55 (by Joe Allen (in 23 hours over a few weeks in 2004)). Neither of these records are particularly hard to beat though. The one-hour limit record is a bit more optimized though: I did a 24x24x24.


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## szalejot (Dec 1, 2014)

Congratulations. Lot of work


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## Randomno (Dec 6, 2014)

I feel there should be some sort of rules/time limits for higher order cubes. I could start on a ridiculously massive cube, and spend several hundred hours total time solving it, and if I did it over a long time (say year), it wouldn't really be too much effort.


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## Mollerz (Dec 6, 2014)

Randomno said:


> I feel there should be some sort of rules/time limits for higher order cubes. I could start on a ridiculously massive cube, and spend several hundred hours total time solving it, and if I did it over a long time (say year), it wouldn't really be too much effort.



Go on then.


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## Randomno (Dec 6, 2014)

Mollerz said:


> Go on then.



Nah, my laptop would burn up just trying to download IsoCubeSim.


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## IRNjuggle28 (Dec 6, 2014)

Randomno said:


> Nah, my laptop would burn up just trying to download IsoCubeSim.


That's the challenge, though. Finding a circumstance where you can actually attempt the puzzle, and not giving up just because it takes forever. We all know that solving a 128 layer cube is pretty easy conceptually. That is not, and never has been, the challenging part of solving a really big cube. If qq ever gets some competition, maybe he'll start actually speedsolving them and spend 3 straight days solving.


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## cmhardw (Dec 6, 2014)

Congratulations! This is an exciting UWR! Thanks for posting your progress and for the link to your clearing method for centers!

Very cool!


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## Randomno (Dec 6, 2014)

IRNjuggle28 said:


> That's the challenge, though. Finding a circumstance where you can actually attempt the puzzle, and not giving up just because it takes forever. We all know that solving a 128 layer cube is pretty easy conceptually. That is not, and never has been, the challenging part of solving a really big cube. If qq ever gets some competition, maybe he'll start actually speedsolving them and spend 3 straight days solving.



As long as your computer doesn't try to shut down the cube simulator every week, you can repeatedly spend a short amount of time over a long period and it wouldn't feel like much of a challenge.


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## qqwref (Dec 6, 2014)

Thanks Chris! I hope some people can find some of the stuff I posted useful, perhaps other people who want to solve something big. Even 20x20x20 is a good start.



Randomno said:


> I feel there should be some sort of rules/time limits for higher order cubes. I could start on a ridiculously massive cube, and spend several hundred hours total time solving it, and if I did it over a long time (say year), it wouldn't really be too much effort.


Well, that's the point, isn't it? It's partially a contest of who is willing to put the most time into it, although of course it's also partially skill-based since being faster will save a lot of time. If it was so easy to spend a couple hundred hours on a single solve, I can only assume it would've been done a few times by now.



IRNjuggle28 said:


> If qq ever gets some competition, maybe he'll start actually speedsolving them and spend 3 straight days solving.


Haha, no way. I would worry about getting some kind of repetitive stress injury. Maybe there's some way to avoid that, but I'm not an expert on this stuff. And there's no competition anyway. For now, the biggest cube I'd consider doing in one sitting is a 50x50x50 or so.


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## WinterCub3r (Dec 6, 2014)

what a waste of time.


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## guysensei1 (Dec 6, 2014)

WinterCub3r said:


> what a waste of time.



Not sure if sarcasm or real


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