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 Post subject: Starminx(I) Edge Help
PostPosted: Mon Feb 14, 2011 5:48 am 
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Joined: Mon Jun 14, 2010 6:59 pm
Location: Crestwood, IL
Does anyone have any algorithms for solving the edges of a Starminx(I)? I thought you would solve them like pyraminx crystal edges but that messes up the centers. Help!


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 Post subject: Re: Starminx(I) Edge Help
PostPosted: Mon Feb 14, 2011 7:16 am 
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I haven't gotten my stickers, so I'm not sure how to solve it, but what about saving the centers for after the edges? Just a thought.

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 Post subject: Re: Starminx(I) Edge Help
PostPosted: Mon Feb 14, 2011 8:02 am 
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Joined: Mon Jun 07, 2010 8:37 am
Location: Waco, TX and South Bend, IN
In solving the Starminx, I have found pure algorithms for the edges, triangle-face pieces, and centers all. However, having only solved it once, there could be much better and more optimable ways of solving it than I do.

I solve one face edges using intuition. I do this for about the bottom half of the puzzle. Then, to cycle three edges (nonpure, meaning other things get messed up), I do L', R, L, R'. [I'm not sure of proper notation, so I will explain how it should look - you hold the Starminx with a pentagonal face facing you, with one of its vertices pointing down. There are six faces you can turn now - U, R, DR, DL, L, in counter clockwise order from the top, and F for turning the front. Doing L', R, L, R' will cycle the top, bottom right, and bottom left edges on the front face.

Sorry if this is confusing, I cannot show pictures at this time. Hope it helps!

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 Post subject: Re: Starminx(I) Edge Help
PostPosted: Mon Feb 14, 2011 9:37 am 
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Joined: Thu Sep 17, 2009 6:07 am
Location: Germany, Bavaria
77mouser wrote:
Does anyone have any algorithms for solving the edges of a Starminx(I)? I thought you would solve them like pyraminx crystal edges but that messes up the centers. Help!
I have done a partial solve yesterday, so far: 1. edges as on a Pyraminx Crystal 2. Centres (I could find a (4,1) commutator for a 3-cycle of centres pretty easily. It is non-pure, but it leaves the edges intact. Small hint: {Try Gelatinbrain 1.1.5 and do: R L' R' L - those are the 4 moves in the commutator and look for an appropriate move for the 1 move in the commutator} 3. the little triangles (=star tips) with a (3,1) commutator.
Originally, I had planned to do it 1. centres 2.edges 3. star tips
In this outline I would use a (3,1) commutator for a pure 3-cycle of the edges.
I think, my new outline saves solves in the first two steps, as there are 12 centres and 30 edges.
And my Pyraminx Crystal solve is based on a 4 move un-pure 3-cycle.

The most tedious part is the star tips solving and this is completely identical in the two outlines.
I have finished this half way, because I have other priorities right now.

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 Post subject: Re: Starminx(I) Edge Help
PostPosted: Mon Feb 14, 2011 3:24 pm 
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Joined: Thu Jul 23, 2009 5:06 pm
Location: Berkeley, CA, USA
I use a [3,1] algo for edges. This algo uses slice moves extensively. I believe you could find it.

In Gelatinbrain 1.1.5, the algo is:

C&2,F'&2,C'&2,
F',
C&2,F&2,C'&2,
F,


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 Post subject: Re: Starminx(I) Edge Help
PostPosted: Wed Feb 16, 2011 1:48 pm 
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Joined: Thu Sep 17, 2009 6:07 am
Location: Germany, Bavaria
@77mouser: Could you solve the Starminx (V1) with the hints so far? What kind of Starminx do you solve (e.g. TomZ's Mini Starminx)?

I do still blieve that it is easier to do the edges in step 1, solving it as a Pyraminx Crystal. Without counting setup moves, a 3 cycle of edges costs 4 moves only, while a pure 3-cycle costs 8 moves. I have a different (3,1) commutator for the edges, but do not need it.

More hints:
{First Notation:
Image
The left two pictures show Gelatinbrain notation, if you orient the dodecahedron as in the picture. The pair of pictures at the left shows 6 faces looking from the front, at the right the 6 faces looking at the backside.
The right pair shows my own notation. I denote inner layer turns with small letters, outer layer turns with capitals (There are a few combinations, though e.g. Br = Back right).

As an example schuma's algoritm above in Gelatinbrain notation is: C&2,F'&2,C'&2,F',C&2,F&2,C'&2,F,
In my notation it is: r2, l‘2, r‘2, R‘, r2, l2, r‘2, R
Here is a picture (out of Gelatinbrain 1.1.5) how the result of schuma's algorithm looks, on a solved Starminx
Image

You would not need an edges algorithm at all, if you start solving the edges like on a Pyraminx Crystal.

In case my hint above was not sufficient, here is an impure (4,1) commutator for the centres:
R L‘ R‘ L Br L‘ R L R‘ Br‘ (Gelatinbrain: C,F',C',F, G, F',C,F,C', G',
shortened to (3,1) R L‘ R‘ Br R L R‘ Br‘ (Gelatinbrain: C,F',C', G, C,F,C', G'with the result:

Image

The most tedious part is solving the startips in step 3. Here is a (3,1) commutator for a pure 3-cycle
R‘2, L2, R2, l‘, R‘2, L‘2, R2, l (Gelatinbrain: C'2, F2,C2,F'&2,C'2,F'2,C2,F&2,)
Image
Close to the end, setup moves become a bit harder. Here is a 10 move algorithm that I have adopted from my Pentultimate solution. It is another 3-cycle with two startips on one face. (It exchanges seemingly two startips.):
L‘ F2 R L‘ U2 L U‘2 R‘ L F‘2 (Gelatinbrain: F',A2,C,F',B2,F,B'2,C',F,A'2,)
Image
}
EDIT: Corrected a typo.

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 Post subject: Re: Starminx(I) Edge Help
PostPosted: Sat Feb 19, 2011 10:28 am 
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Joined: Mon Jun 14, 2010 6:59 pm
Location: Crestwood, IL
Thanks for all the help! I got it. I think maybe I will solve it edges first next time though.
Konrad-I have a TomZ Starminx(not a good turning one :( but it still turns)


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