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 Post subject: Re: Dayan Gem IV (Dino Skewb truncated octahedron) Available
PostPosted: Tue Jan 10, 2012 4:31 am 
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About the Nature of the Gem iV

I had a constructive PM discussion with RubixFreakGreg about the closest relationship of the Gem iV with either the Dino Skewb or the Compy Skewb.
(I asked Greg for permission to quote him.)

I vote for the Compy Skewb and Greg for the Dino Skewb. :)
When I asked Tom for his opinion he answered
TomZ wrote:
Hi Konrad,

I can't say much other than that it's a mix of both. The Dino Skewb is a subset of the Gem which is a subset of the Compy Skewb.
Mechanically (other than the not-trivial tips) they're the same as both the Dino as the Compy Skewb so it really can be a shapemod of either one.

The cuts on the Gem meet up precisely where the Skewb faces are, so it could be said to be closer to a Dino Skewb. However, if you truncated the square faces inward the cuts would no longer meet precisely and it'd be closer to a Compy. Again, it's all a matter of shapemodding (and changing the mech size accordingly).

Though, a shapemod into a Dino Skewb would be far more feasible than on in to a Compy Skewb.

Best regards,
Tom
Is it possible that the standpoint of a designer and the standpoint of a solver produce different results?
When I started to solve the Gem iV I recognized immediately that my Compy Skewb method is sufficient to solve the Gem iV, while the Dino Skewb method is lacking a lot. The Gem iV has 32 pieces and two piece types more than the Dino Skewb.
I agree that the Gem iV is between the Dino Skewb and the Compy Skewb. Solvingwise it is for me closer to the Compy.
My argument is, you can grade down the Compy solution immediately to the Gem iV solution, while you need some additional strategies to upgrade a Dino Skewb method.

I guess it is fair to say that two different points of views are possible, the modder and the solver standpoint.
Please build your own opinion.

Before I go on, let me say that I like both TomZ puzzles the Dino Skewb and the Compy Skewb. The Compy is one of my favourites though. :D It looks like a cubic Elite Skewb and solving it is fun. BTW, in some sense the inventor :idea: of this puzzle is Carl Hoff.

Here follows some history of our PM discussion:

RubixFreakGreg wrote:
Konrad wrote:
because you have given the name to this thread, you can possibly answer my question:
Was this puzzle ever made before?
I tried Google and looked at all octahedra in the museum, but I found no reference.
This puzzle was never made before.

When I studied the depth of the cuts, I noticed on the cuts coincide on the square faces, just like on the dino cube, so it is equivalent to the dino cube.

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Konrad wrote:
How did you come up with the name `Dino Skewb truncated octahedron`?
Since it is a dino skewb, all that's left is the shape.
Konrad wrote:
Do you agree that a Compy Cube reference is a bit closer?
No, not really (see the link on top).
I beg to disagree :) To me the Compy Skewb is closer for two reasons.

1. A Compy Cube is a shallow cut Dino Cube.
A Compy Skewb is a shallow cut Dino Skewb.
So far we should all have agreement.

The Dino cuts on the Gem iV are shallow in the sense that they do not go through the middle of three other centres of rotation as on a Dino Cube or a Dino Skewb.
If you look at Gelatinbrain 4.1.7 which is the not truncated Gem iV, the Dino cuts go neither through the middle of a hexagonal centre (which are the vertices of the dual cube) nor through the middle of a corner (which correspond to the face centres of the dual cube)

2. Looking at it from the viewpoint of a solver:
When can we say that two puzzles correspond to each other and are shape modifications only?
I would say a direct correspondence requires a 1:1 relationships between visible piece types, the pieces the solver has to care about.
Let's enumerate the three puzzles Dino Skewb, Gem iV and Compy Skewb
Dino Skewb:
24 corner tips
24 faces
48 total

Compy Skewb as in Gelatinbrain 3.2.11 with 8 undivided corners. (Tom's Compy has additional non-trivial tips = Skewb corners)
8 corners
6 Skewb faces
24 Dino Skewb faces
24 X faces (called Tetrahedral Twin edges by Carl)
24 Dino Skewb edges
86 total
Gem iV
8 centres
24 corners
24 face triangles
24 edge triangles
80 total

All three are not directly equivalent shape modifications, but regarding a solution method there is a close relationship between the Compy Skewb and the Gem iV. Only the 6 Skewb centres are missing on the Gem iV.
In other words I can solve the Gem iV because I know how to solve the Compy Skewb.
I cannot solve the Gem iV if I know a Dino Skewb method only.
Naming proposal for Gem iV pieces
Image
I call a turn of a hexagonal face a Dino turn, while a turn through the centre of the puzzle is a Skewb turn.
A Dino turn will not affect any grouped Dino edges.

Mapping between Gem iV and Compy Skewb pieces
Image
Only the Skewb centres do not exist (are not visible anyway) on the Gem iV.

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 Post subject: Re: Dayan Gem IV (Dino Skewb truncated octahedron) Available
PostPosted: Tue Jan 10, 2012 1:39 pm 
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I like the discussion of correspondence / equivalence between the puzzles but I think oftentimes the lack of a particular piece makes another type of pieces easier enough that the entire solve order should be changed.

In the case of the Dayan Gem IV, I'd suggest reduction to a Dino Cube. The only tricky thing is that the identical-looking small triangle pieces between two corners (4.1.7 edges) along a Dino edge are different than the small triangle pieces between two corners that share a "square face". In a reduction solve, the two small triangles between two corners that make up the Dino edge should be grouped together with the two corners. The other triangles should be grouped with the hexagon centers.

My solving strategy will be:

0) Put hexagon centers into correct color scheme
1) Attach the non-Dino-edge small triangles to the hexagon centers using [1,1] commutators (shorten to 3-move conjugate for reduction solve)
2) Pair up corners using [3,1] commutators (shorten to 5-move conjugate for reduction solve)
3) Group Dino-edge triangles with corner pairs with [3,1] commutators (shorten to 7-move conjugate for reduction solve)
4) Solve reduced Dino Cube

This solve order is extremely similar to the Dino Skewb (3.2.13). The trick that I used on the Dino Skewb to get a 68 move solve doesn't work on this puzzle and with the extra pieces I think a 125-move solve should be a reasonable target.

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 Post subject: How to solve the Dayan Gem iV
PostPosted: Tue Jan 10, 2012 3:51 pm 
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I'm opening this thread to avoid the trouble for Dave to move solution oriented posts to a new thread. :) [Admin: Posts merged over anyway, but thanks :)]
When I discussed the nature of the Gem iV above, Brandon gave these hints:
bmenrigh wrote:
I like the discussion of correspondence / equivalence between the puzzles but I think oftentimes the lack of a particular piece makes another type of pieces easier enough that the entire solve order should be changed.

In the case of the Dayan Gem IV, I'd suggest reduction to a Dino Cube. The only tricky thing is that the identical-looking small triangle pieces between two corners (4.1.7 edges) along a Dino edge are different than the small triangle pieces between two corners that share a "square face". In a reduction solve, the two small triangles between two corners that make up the Dino edge should be grouped together with the two corners. The other triangles should be grouped with the hexagon centers.

My solving strategy will be:

0) Put hexagon centers into correct color scheme
1) Attach the non-Dino-edge small triangles to the hexagon centers using [1,1] commutators (shorten to 3-move conjugate for reduction solve)
2) Pair up corners using [3,1] commutators (shorten to 5-move conjugate for reduction solve)
3) Group Dino-edge triangles with corner pairs with [3,1] commutators (shorten to 7-move conjugate for reduction solve)
4) Solve reduced Dino Cube

This solve order is extremely similar to the Dino Skewb (3.2.13). The trick that I used on the Dino Skewb to get a 68 move solve doesn't work on this puzzle and with the extra pieces I think a 125-move solve should be a reasonable target.
Actually I use a very similar reduction method for the Compy Skewb (Gelatinbrain 3.2.12; in my case TomZ's wonderful physical version) and for the Gem iV.
Your steps 0 and 1 are the same in my method. (step 1 in [1:1] conjugates). I do step 2 and 3 somehow interleaving doing half pairs of the Dino edges (5 move conjugates) and then join two half pairs usually in 5 moves([1:3]) at the end with [3,1] commutators.
Necessary setup moves are easy because any face turns do not affect the grouped Dino edges.
Step 4 is naturally the same.

I do not aim for a low move count. In a sense, I find the Compy Skewb less confusing because the colour scheme is obvious, whereas it is harder to memorize an 8 colour scheme for the Gem iV. On the other hand the non-trivial tips and the Skewb centres add some difficulty to the CS.

The reason I still maintain my judgement that the Gem iV is closer to the Compy than to the Dino is the fact that step 0 and 1 do not exist on a Dino Skewb.
But yes, all three are close together, anyway. :)

EDIT: I find it visually intriguing that the triangles on a face can be misinterpreted easily when looking for a piece. I mean the two piece types `Dino edge` and `face triangle` (or whatever you want it to call) look identical at a quick glance.
Image

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Last edited by Konrad on Tue Jan 10, 2012 5:03 pm, edited 1 time in total.

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Tue Jan 10, 2012 4:11 pm 
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Yeah my suggested solve is a progression of reduction.

Gem IV -> Dino Skewb -> Dino Cube -> Solved

Julian said the Compy Skewb and it's partner 3.2.11 can be reduced to a Dino Cube too. I haven't tried (or opened or otherwise studied) either of them yet so I can't really comment on how they relate.

It should be said that on the Gem IV the centers are in two orbits, the dino-edge-triangles are in two orbits, and the hexagon-center-triangles are in two orbits. This is more natural on the octahedral shape mod of this puzzle than on the cubical one because in the octahedral version, all pieces of the same color happen to also be in the same orbit. On the cubical version, each color has pieces in each orbit. This means you're unlikely to even notice the orbits on the Gem IV but you probably will notice them on the Dino Skewb and similar puzzles.

Michael's move count on 3.2.11 (262) and 3.2.12 (294) looks within reach for a decent reduction solve but I won't know how good that move count is until I give them a try myself.

Julian, if you're reading this, you should try your reduction ideas on them :)

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Last edited by Brandon Enright on Tue Jan 10, 2012 5:22 pm, edited 1 time in total.

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Tue Jan 10, 2012 5:22 pm 
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bmenrigh wrote:
...Julian said the Compy Skewb and it's partner 3.2.11 can be reduced to a Dino Cube too. I haven't tried (or opened or otherwise studied) either of them yet so I can't really comment on how they relate.

...
In my view 3.2.11 is almost identical to 3.2.12 (= Compy Skewb). The difference are just the non trivial tips = Skewb corners.
Brandon, have you got the physical version of the Gem iV?
This may be another case where you prefer the Gelatinbrain version :lol:
BTW, how is your Starminx nowadays?
My black Dayan Gem iV turns acceptable, no pops and no danger of explosion :lol:
Acceptable for such a complex puzzle that is, while the TomZ Compy Skewb is excellent - being a bit more complex. :)

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Tue Jan 10, 2012 5:32 pm 
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Konrad wrote:
Brandon, have you got the physical version of the Gem iV?
It's sitting at the post office and I haven't had time to pick it up yet :(
Konrad wrote:
This may be another case where you prefer the Gelatinbrain version :lol:
We'll see, I do like that it's an Octahedron but simpler than 4.1.7. It should make for a good physical solve.

Konrad wrote:
BTW, how is your Starminx nowadays?
The MF8 Starminx is still terrible despite taking it apart and lubing all of the pieces and adjusting tensions. I also have TomZ's new Starminx (the medium one, not the mini) and it's great. The way the face cuts meet at a corner on the Starminx seem to make it hard to fully prevent catching though. The Starminx inside of Eric's Master Pent and also TomZ's Multidodecahedron both function a bit better.

Konrad wrote:
My black Dayan Gem iV turns acceptable, no pops and no danger of explosion :lol:
Acceptable for such a complex puzzle that is, while the TomZ Compy Skewb is excellent - being a bit more complex. :)
The previous three Dayan Gems all turn "okay" but not great. It'll probably be acceptable. The more complex the puzzle gets (e.g. Starminx) the more the turning quality matters.

I also have TomZ's Dino Skewb which is one of my favorite puzzles. It was the first fewest moves record on Gelatinbrain that I feel I really earned. Since then I have earned many more but the first still has a special place in my heat.

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Fri Jan 13, 2012 4:46 am 
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bmenrigh wrote:
...The previous three Dayan Gems all turn "okay" but not great. It'll probably be acceptable. The more complex the puzzle gets (e.g. Starminx) the more the turning quality matters.
My Gem II out of transparent plastic turns not so good. The others are black and Gem III turns best, but I consider the difficulty of Gem iV quite a bit higher.
bmenrigh wrote:

I also have TomZ's Dino Skewb which is one of my favorite puzzles. It was the first fewest moves record on Gelatinbrain that I feel I really earned. Since then I have earned many more but the first still has a special place in my heart.
I can understand this :)

I decided to copy some notation oriented stuff from the other thread
Konrad wrote:
bmenrigh wrote:
...It is basically Gelatinbrain's 4.1.7
I guess we should agree upon a more intuitive notation for octahedra. Probably, there will be a discussion about some move sequences soon :wink:
The Gelatinbrain notation is not very intuitive at all.

Here is my proposal
Image
We look at the octahedron sitting on a table one corner and one face (F) pointing at us.

The slice moves equivalent to the dodecahedron notation we came up with:http://twistypuzzles.com/forum/viewtopic.php?f=8&t=22683&p=272521
Luke wrote:
The Gelatinbrain notation is understandable, as each face is the same as a cube corner, and people describe cube corners as 'DBL' and so forth. Nevertheless, I do like Konrad's notation. Now, who's going to sort out the icosahedral notation? :lol:
Andreas Nortmann wrote:
Since I came up with the same notation as Gelatinbrain it must be an obvious one.
Its single disadvantage matters only for move-sequence-addicts: It uses more than one letter per face.
Konrad wrote:
I did not say that the Gelatinbrain notation is not understandable. I just said that it is not very intuitive. :wink:
Many people seem to feel the same and came up with notations similar to mine - at least U, R and F I have seen identically several times.
Even if I come from the dual cube, I would end with a slightly different notation:

Image

I start with the octahedron and the cube inscribed and view the cube as in Gelatinbrain. I name the cube corners as usual. I look down to the top corner of the octahedron / the U face of the cube.
Now I would turn the octahedron by the smallest angle possible to get to the shape used by Gelatinbrain.
URF (or UFR) would either be to my front or to my right. In Gelatinbrain it is back from me.

My notation is shorter, yes, but this is not the main reason why I prefer it. It is more intuitive for me, at least for U,R and L; intuitive for a human being looking at the physical puzzle on a table before him / her.

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Fri Jan 13, 2012 5:26 am 
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Konrad and Brandon (since only you two are in this thread currently)

I'm starting to look at my gem IV but I'm at a disadvantage since I don't have a compy skewb or a dino skewb, nor any of the other gems. This puzzle is quite a new experience for me. So I'd like to ask a few questions based around the general method presented here.

Quote:
0) Put hexagon centers into correct color scheme

Is there a some trick to remembering this, or is it just solving it enough to learn it?

Quote:
1) Attach the non-Dino-edge small triangles to the hexagon centers using [1,1] commutators (shorten to 3-move conjugate for reduction solve)

As I understand this, it's moving a triangle onto a hexagon face using a slice move, putting the piece into position by turning the hexagon face and then moving it back. Is that correct?

Quote:
2) Pair up corners using [3,1] commutators (shorten to 5-move conjugate for reduction solve)

Do you mean just 3-cycling corners using something like (using the notation in this thread) U R U' r U R' U r' ? If not, can you explain further. If so, how do you shorten that to a 5-move conjugate?

Assuming I've understood that stuff...

Quote:
3) Group Dino-edge triangles with corner pairs with [3,1] commutators (shorten to 7-move conjugate for reduction solve)

By this stage, I would have corner pairs together, but that sequence above would also move around dino-edge triangles separately. So I might then need to find a sequence here to move single dino-edge triangles around. Which means that simply turning hexagonal faces in the "3" part of the [3,1] commutator won't do. Can you give me some tips here?

Thanks in advance!

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Fri Jan 13, 2012 7:12 am 
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rline wrote:
Konrad and Brandon (since only you two are in this thread currently)

I'm starting to look at my gem IV but I'm at a disadvantage since I don't have a compy skewb or a dino skewb, nor any of the other gems.
You can always use Gelatinbrain 4.1.7 trying something new to find.
rline wrote:
This puzzle is quite a new experience for me. So I'd like to ask a few questions based around the general method presented here.

Quote:
0) Put hexagon centers into correct color scheme

Is there a some trick to remembering this, or is it just solving it enough to learn it?
The problem is solved when the centres are solved in the second step. You always have the corners giving you three adjacent face colours. The colour scheme is hard to remember in this early stage. You could make some colour model like putting some of the scrap vinyl onto another octahedron. Or look at this picture :)
Image
rline wrote:

Quote:
1) Attach the non-Dino-edge small triangles to the hexagon centers using [1,1] commutators (shorten to 3-move conjugate for reduction solve)

As I understand this, it's moving a triangle onto a hexagon face using a slice move, putting the piece into position by turning the hexagon face and then moving it back. Is that correct?
Exactly :) , for convenience use a Skewb move instead of a slice move. I find it better to turn a full half of the puzzle in such cases.
rline wrote:

Quote:
2) Pair up corners using [3,1] commutators (shorten to 5-move conjugate for reduction solve)

Do you mean just 3-cycling corners using something like (using the notation in this thread) U R U' r U R' U r' ? If not, can you explain further. If so, how do you shorten that to a 5-move conjugate?
Your example is an example of a pure 3-cycle of half pairs. If you start with the slice move r you can stop after 5 moves because the remaining 3 face moves are not necessary for reduction.
rline wrote:

Assuming I've understood that stuff...

Quote:
3) Group Dino-edge triangles with corner pairs with [3,1] commutators (shorten to 7-move conjugate for reduction solve)

By this stage, I would have corner pairs together, but that sequence above would also move around dino-edge triangles separately. So I might then need to find a sequence here to move single dino-edge triangles around. Which means that simply turning hexagonal faces in the "3" part of the [3,1] commutator won't do. Can you give me some tips here?
You need to find commutators where a edge triangle is moved. Try this:
My notation
(bl BL)’ U (bl BL) u (bl BL)’ U’ (bl BL) u’
(BL added for easier turning)

Gelatinbrain
DRB'&2, URF, DRB&2, URF&2, DRB'&2, URF', DRB&2, URF'&2
rline wrote:

Thanks in advance!
Have fun

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Fri Jan 13, 2012 7:30 am 
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Thanks for your reply Konrad,

Quote:
You need to find commutators where a edge triangle is moved. Try this:
My notation
(bl BL)’ U (bl BL) u (bl BL)’ U’ (bl BL) u’
(BL added for easier turning)

I also happened to find one: (r l' r' l) R' (l' r l r') R

Quote:
Have fun

I hope to! :D

Actually, I thought of a slightly different approach to solving it. I'll have a look at that as well and maybe post it.

Thanks again

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Tue Jan 17, 2012 10:01 pm 
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rline wrote:
Actually, I thought of a slightly different approach to solving it. I'll have a look at that as well and maybe post it.
Konrad wrote:
I do step 2 and 3 somehow interleaving doing half pairs of the Dino edges (5 move conjugates) and then join two half pairs usually in 5 moves([1:3]) at the end with [3,1] commutators.

Well I don't know if the way I found is what you're saying here Konrad, but I thought I'd post it anyway. It uses no commutators.

The outline is the same
1. Place centers
2. Place non-Dino-edge small triangles
3. Match two half-pairs of a dino edge.
4. Place reduced dino edges

Step 3 is the different bit. I find a half pair - meaning a corner with a matching dino edge triangle (if a corner doesn't have a matching triangle, I use this same technique to attach it) and then find its matching corner-triangle pair. Bring them together with a skewb turn, move the reduced dino edge onto a different hex face using EPS and then undo the skewb move.

I do this for all 12 of them. This is just like making edge pairs on a rubiks 4x4x4. To me this method feels much more like "solving" the puzzle and I now really like solving the gem.

The only thing is that sometimes at the end the last two dino edges will be nearly reduced. Each will have one wrong triangle (they're swapped). I haven't found a way to deal with this without using a commutator. But even if this happens, I'm happy that I'm only using a max of 1 for the solve.

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Sat Feb 25, 2012 4:49 am 
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rline wrote:
1. Place centers
2. Place non-Dino-edge small triangles
3. Match two half-pairs of a dino edge.
4. Place reduced dino edges

Step 3 is the different bit. I find a half pair - meaning a corner with a matching dino edge triangle (if a corner doesn't have a matching triangle, I use this same technique to attach it) and then find its matching corner-triangle pair. Bring them together with a skewb turn, move the reduced dino edge onto a different hex face using EPS and then undo the skewb move.

I do this for all 12 of them. This is just like making edge pairs on a rubiks 4x4x4. To me this method feels much more like "solving" the puzzle and I now really like solving the gem.

The only thing is that sometimes at the end the last two dino edges will be nearly reduced. Each will have one wrong triangle (they're swapped). I haven't found a way to deal with this without using a commutator. But even if this happens, I'm happy that I'm only using a max of 1 for the solve.

I bought a Gem IV and figured out commutators for each type of piece. The one for the corners also moved edges, so I solved the corners before the edges. I like commutators and so was pleased with the method I worked out using them.

Then I tried rline's approach as outlined above. Wow! I love it! Steps 2 and 4 are so easy. Step 3 gave me trouble at first, but after a few solves, it is not difficult at all. I do use an 8-step commutator to get some of the last Corner-Edge pairs paired up, but for the most part do not have to use any 8 or longer step commutators.

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Sat Mar 24, 2012 7:48 am 
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Today I spent some time with the Gem4. Out of the box it was one of the worst turning puzzles I have recieved, but after some tensioning and lubing today I was seriously surprised at how well it has come up.. I have to say it now turns quite nicely, I honestly can't believe the difference :) .

For me it was natural to see it as a Master Skewb Hex, like a Skewb Diamond. And I set out to reduce it under that influence.

1. Place 2 opposing corners on one square to to determine the colour scheme: then place the 4 adjacent matching centres (this places all centres).

2. Keeping centres in place solve the `square (face) triangles` by: a skewb turn, face turn, undo skewb turn. Once they are solved they determine the placement of the corners. The Hex skewb squares and triangles can now be moved independantly by skewb turns for setups of corner pieces with no need to undo setups.

3. Place corners: You can twist in quite a few corners with face turns only to begin (provided you are not doing Skewb turns yet), you can complete more than one square doing this. Then, when Skewb turns are needed, move to EPS (R'FRF') turns to complete the first 3 squares (this preserves the `square (face) triangles`). Twist completed corners/squares out of the way of sequences with skewb turns.

4. Place remaining corners (last 3 squares): I can always pick up the rest 2 at a time easily with: [(R' f R) F' (R' f' R) F]. Most of the time there is a square with a corner that needs to move to the opposing position (see my diagram), just use this and twist the recieving position for the front corner into place (otherwise a single turn `setup`and 'undo` by a face turn is available at the back: U face).

5. 3cycle `Skewb triangle` triangles (dino edge triangles) with [(r' l r l') R' (l r' l' r) R] You can do any amount of face turn setups with this while working on seperate orbits, then return them and continue to the other orbit (my diagram here is showing the orange face as R, and white as F).

6. Solve the reduced Skewb Hex without making face turns.

After solving it like that I read the posts here and tried out Rline's method, I like the idea, very nice. The difference I found was that I had to do a lot of `searching` (which was time consuming), compared to my method and then it was a bit of a let down to not be able to flip a `dino` edge and return it to finish it off easily and needed that commutator anyway. You don't need EPS to exchange out your edges, just an `up, replace, down` 3 move sequence is enough. Anyway, thanks to everyone for sharing.

In the end I don't think what I am doing is a real big change to other methods mentioned here, just that it is a way of not having to undo setup moves- which is nice for me. It's just an idea.

Cheers,
Burgo.


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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Sat Mar 24, 2012 6:16 pm 
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Thanks for posting your method Burgo. It more and more amazes me how there can be sometimes a lot of differrent approaches for a single puzzle.

If anyone wants a more "visual" idea of my method above (I originally just posted text), they should have a look at the video tutorial I made for this puzzle at http://rubiksultimatesolution.blogspot. ... em-iv.html

I completely agree with Burgo that this puzzle initially wasn't great, but it now turns pretty well.

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Sat Mar 24, 2012 8:30 pm 
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I just tried Konrad's conjugate [(Rr L' Rr') l' (Rr L Rr') l] in my step 5, it's really smooth. I have tried all of the methods now.. it's interesting that face turns make the setups in the Dino reduction method and Skewb turns make the setups in the Skewb Hex reduction method, but that in both methods we conserve the `square (face) triangles` (but in a completely different way).

This is a really nice cube, I thoroughly recommend it :D .

Cheers,
Burgo.

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PB 3x3 55sec Jan 2011 (When I was a kid 1:30 was speedcubing so I'm stoked).
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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Sun Mar 25, 2012 4:35 am 
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Burgo wrote:
...with [(r' l r l') R' (l r' l' r) R] ...
Are f, l and r slice turns or wing turns (i.e. just the layer behind F or both F and the layer behind F)? I'm at a bit of a disadvantage in that I haven't solved the other Skewb puzzles, so your insights are very helpful :shock:

I disassembled mine and lubricated it and it turns quite well. I fixed the annoying spring noises by putting lubricant on the spring ends.

Having played with the Gem IV for a few hours, I am surprised to see more than one strategy. It feels very constrained compared to the Gem III :mrgreen: .

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 Post subject: Re: How to solve the Dayan Gem iV
PostPosted: Sun Mar 25, 2012 5:06 am 
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Hi Pete,

R, L & F are face turns
r, l & f are slice turns under that face
Rr, Ll & Ff are both slice and face together
Konrad has a diagram ^^ for face names.

Pete the Geek wrote:
It feels very constrained compared to the Gem III
It has 2 seperate orbits where certain pieces can't transfer to half of the faces [(R,L,D,B)(F,B,BR,BL)], and corners can only go to diagonally opposite sides of the square faces, and you can't flip dino edges (for example). So there are a lot of restrictions, but in solving you can make the restrictions work for you too :wink: .

It must be quite difficult if you have never tackled a Skewb before. If you make twists using only the Skewb turns (and not face turns) you will have a Skewb Hex, I would suggest solving it like that a few times first to get used to how a Skewb works (or as a Dino Cube by making only face turns).

Cheers,
Burgo.

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PB 3x3 55sec Jan 2011 (When I was a kid 1:30 was speedcubing so I'm stoked).
1st 3x3 Earth (nemesis) solve Jan 2011 My You Tube (Now has ALLCrazy 3X3 Planets with Reduction)


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