Cube 7x7x7???

[poptheman1]

Is it possible to make a 7x7x7 un-pillowed if you extend the pieces? Im curious'

P.s. Sorry if this is in the wrong forum.

 

[jcuber]

It belongs in the hardware area, and you are right, it is possible. However there is more torque on the corners and it is more likely to break. With cubes 7x7 (and higher in the future), I find the pillowing makes it fit your hands better.

 

[calekewbs]

yes? lol but the peices wouldn't be nearly the same size.

Edit: and i agree with Jcuber. it actually makes it feel more secure to me.

 

[rjohnson_8ball]

Yes, but the pieces might not be equal area. Imagine adding material onto a pillowed 7x7. I want to get my hands on a pillowed 3x3 or 4x4... As just said, the torque on the pieces would be different.

 

[poptheman1]

It would be like a v-cube 6, right? Its centers are 10x10 mm, edges are 10x13 mm, corners are 13x13 mm.

 

[calekewbs]

no. lol it would be bigger... i think. lol don't quote me on it.

 

[TomZ]

Torque and having the corners break (I'm not cutting into the actual mechanism, am I?) have fairly little do with this. If I redesigned the puzzle from scratch the corners could end up breaking but a little cutting into it or extending isn't going to affect their strength.

If I extended the V-cube pieces as is, you would get something similar to the V6 - unequal cubies.

On the other hand, if I sanded down to make it cubic, I would get something similar to this:

That could then be modified using some thin plastic to behave like the floppy cube, making it (look like) a fully proportionate 7x7.

 

[panyan]

no. lol it would be bigger... i think. lol don't quote me on it.

it would be bigger

i had to quote you

 

[Ton]

There is a concept of Max Caley see my article from 2004
http://www.speedcubing.com/ton/Archive/News2004_2.htm

 

[LNZ]

No. If you rotated a perfectly cube shaped 7x7x7 45 degrees, one edge piece will fall out as there's nothing to hold it in place. Fore the 6x6x6, this edge piece is just held in place bt the other pieces.

Here's the equation:

L*sqrt(2)-L = sqrt(2)*(2*L/N)

Where: N= Cube order, L= Cube raduis.

N is equal to 4+sqrt(8)=6.83 (aprox)

So for N=7 or higher, the cube must bepillow shaped to keep it stable.

 

[TomZ]

LNZ, it most certainly is possible to construct a cube shaped 7x7, in more ways than one.

Firstly it is possible to make the outer layers thicker and achieve the same results. If you actually thought up the equation you posted yourself you would see this. This technique is used on the 6x6 as it is just barely possible but they choose pillowing on the 7x7 because the thicker layers would be awkward.

Secondly, it is possible to do as I showed in my earlier post, curving the center pieces. Thirdly, this method can be modified to achieve a "floppy" 7x7.

 

[LNZ]

I do know there are multiple ways to create a cube shape 7x7. But the reason I showed in my last post was the reason that cubes 6x6 or higher were declared "impossible" to make commercially for over 20 years.

Verdes worked out a way to get past this problem by making the 7x7 cube pillow shaped instead.

You can make a cube shaped 7x7 by using magnets. I saw a Youtube video on some making a fully functional 3x3x3 cube using magnets.

On another Youtube video, someone makes a 1x1x2 cube and a 2x2x1 cube by again using magnets.

And I will soon be solving a 1x3x3 cube. I ordered one off Ebay about 3 days ago.