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 Post subject: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 12:46 pm 
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EDIT December 10th 2013: Because Eitan' s Star is a real challenge, I thought I should maintain a list of known solvers at this prominent place.
EDIT December 15th 2013: added Andrea
EDIT December 29th (14.)
EDIT December 30th, (15. & 16.)
EDIT January 18th 2014, 17.
EDIT January 21st 2014, 18.
EDIT January 26th 2014, 19. and 20
EDIT January 28th 2014, 21.
EDIT March 5th 2014, 22.
EDIT March 8th 2014, 23.
EDIT March 14th 2014, 24.
EDIT March 15th 2014, 25.

1.Burgo, 2. rline, 3.DKwan, 4. Pete, 5. Konrad, 6. Bendup, 7. Dreiser,
8. Eitan the designer himself(pirsquared)
9. Cubysognathus, 10. alacoume, 11. Puzzlemad, 12. doctor twist, 13. Andrea, 14. Derek Bosch, 15. gdr, 16. AMatureCuber, 17. Ghost_Cake, 18. D_Lillibridge, 19. AndyChilly, 20. BelcherBoy2000, 21. themathkid, 22. Naz, 23. Ferd Berfel, 24. MennoKnight, 25. Kevin


Please, send PM to Konrad, if I missed anybody.


I thought I would start with a proposal for a notation.
We have one introduced for the Bauhina dodecahedron here.
The Bauhinia corresponds logically to a shallow cut Face Turning Icosahedron (FTI) Gelatinbrain 2.1.1.

A bit of background:

As far as I know, Eitan's Star is the first mass-produced FTI ever.
Eitan informed us here about the plan.
Eitan has originally called his puzzle DeFTI (For Deeper cut Face Turning Icosahedron).
(It is identical to the Radiolarion 3 from Jason Smith)
Eitan wrote about the original 3D printed DeFTI here in September 2010.

The notation should be identical for all FTI and in a logical sense the Bauhina is one.

Therefore, I propose to use the very same notation for Eitan's Star as for the Bauhinia and keep the identical translation from Gelatinbrain to a notation that can be better memorized.
Here is a picture showing both notations based on Gelatinbrain 2.1.3
Image
So, if somebody wants to propose move sequences for Eitan's Star, he/she should either use Gelatinbrain or this proposed notation.
Brandon has made a very nice Sequence utility here.
You can translate Gelatinbrain sequences to this notation (Brandon was friendly enough to call it "Konrad's Vertex-Turning Dodecahedron" notation).
If I will ever describe a move sequence here, I shall use both, Gelatinbrain and THIS (i.e. Konrad's).

Maybe, somebody would criticize that the one letter faces U,L,R are not visible on the frontview.
If you look at the turnable layers, it makes perfect sense that the leftmost in the frontview (to your left) becomes L and the rightmost R and the one on top (three pieces can be seen on the frontview) becomes U.

BTW, Gelatinbrain uses 10 colours, opposite faces are identical.

You may want to compare this notation directly with the VTD notation:
Image

In my opinion, the problems with solving Eitan's Star are more on the practical level (getting used to setup moves and reverse them correctly.)
The theory (i.e. finding commutators for the four piece types) will be not so hard for those who have mastered the Bauhinia :)

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 3:08 pm 
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I will use Konrad's notation

1. Solve the long triangles adjacent to the face center triangles with simple [1,1] comutators:
FR' FL FR FL' = [FR' , FL]

2. Solve the corners with [3,1] comutators (or [[1.1],1]):
FR' FL FR FDR' FR' FL' FR FDR = [[FR' . FL] FDR]

It works to place the corners with orientation correct already. If the orientation isn't correct, the corner can be changed in place, then twisted. Undoing all those moves will result in comutators that solve the orientation.
A way to change the UFR UFL FL F FR corner in the left notation picture can be done with FR' FDR FR' for example.

3. Solve the center triangles with [4,1] comutators
[[FR' , FL] , D]

Steps 2 and 3 are independent of each other and can be switched.

4. Solve the edges with [3,3] comutators (or [[1.1],[1.1]). For this I am in the right picture to make all moves and edges more visible:
[[B' . R] , [L . BL]]
Attachment:
edte tri 1.jpg
edte tri 1.jpg [ 184.66 KiB | Viewed 8281 times ]

[[B' . R] , [L . BL']]
Attachment:
edge tri 2.jpg
edge tri 2.jpg [ 185.41 KiB | Viewed 8281 times ]

[[B' . R] , [BL' . L']]
Attachment:
edge tri 3.jpg
edge tri 3.jpg [ 180.14 KiB | Viewed 8281 times ]

[[B' . R] , [BL' . L]]
Attachment:
edge tri 4.jpg
edge tri 4.jpg [ 186.46 KiB | Viewed 8281 times ]


I decided to include four pictures for the solving of the triangles due to the fact that the setup moves for these pieces are very extensive. As a matter of fact they are what's actually the difficult task and require pen and paper towards the end. At least for me. So having different choices of algorithms and pictures to look at might help. It might not really help in time though. Just using pen and paper and writing down up to 10 setup moves might still be faster than looking for one of the four sequences I put down to save time. I never bothered testing on the applet.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 3:22 pm 
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For everyone who wants to solve the corners first instead of the face triangles because the color sceme isn't familiar and well known yet, there is also a way to cycle the long face triangles around without breaking corners or face centers.
It takes more moves to solve it that way but after corners and center face triangles step 3 would be a [3.3] comutator:

[[F . FR'] , [D . FDL']]

Attachment:
face tri.jpg
face tri.jpg [ 182.84 KiB | Viewed 8276 times ]


It's difficult to see but the bottem left pink face DL has a red triangle now. I didn't look for more ways but I suppose the set up moves for face pieces are easier to accomplish.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 4:13 pm 
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alaskajoe wrote:
3. Solve the center triangles with [4,1] comutators
[[FR' , FL] , D]

This can be done pure in [3,1] == [[1:1],1] == [[DAC:GKD],FBA]

GB's notation: [DAC, GKD, DAC', FBA, CDA, DGK', CDA', AFB']
Konrad's notation: [FR, DR, FR', UFL, FR, DR', FR', UFL']


Personally, I'd recommend doing corners first, then the wide-triangles with [3,1] commutators, then center triangles with [3,1] commutators, then finish with the edge-wings.

What I'd actually end up doing is the 3 corners around a face, then the wide triangles on that face, top down to the bottom. This will give you much more setup freedom for the 60 wide triangles.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 4:25 pm 
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I have started to solve the corners. It wasn't hard till I ended up with one corner twisted. Is that possible?
/Andreas


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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 4:29 pm 
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Usually I read a conjugate as [X:Y]

For those not familiar with commutator/conjugate notation, I'll translate alaskajoe's sequence to the full length and to Gelatinbrain:

[[F . FR'] , [D . FDL']] = [[F : FR'] , [D : FDL']] = F FR' F' D FDL' D' F FR F' D FDL D'
Gelatinbrain: [ADE, CDA', ADE', KED, EJF', KED', ADE, CDA, ADE', KED, EJF, KED'] = [[ADE:CDA'],[KED:EJF']]
You can cut and paste the full length sequence into Gelatinbrain 2.1.3.

Actually, I had the same idea as alaskajoe in his first post:
Memorize the colour scheme and do the wide triangles first. (I called them by myself "outer centres" because they surround the triangle centre.)
We have 60 of them and only 12 corners.
A [1,1] commutator for 60 pieces will save a lot of moves.
On the other hand, it might be not so easy to memorize 20 colours.
So, my second thought was the same as in alaskajoe's second post: do the corners first.

Both methods have their merits and I'll see if I can find a good colour scheme supporting the first method :roll:

I have not checked your other sequences, but probably mine are similar.
All Bauhinia triangle sequences will translate nicely to edges cycle on Eitan's Star.

So, the theory is known. Still, solving the 152 pieces will take a while in practice :wink:

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 4:31 pm 
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andand wrote:
I have started to solve the corners. It wasn't hard till I ended up with one corner twisted. Is that possible?
/Andreas
NO!
Brandon mentioned that the corner caps can be twisted on their own. Probably, this happened to you.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 4:33 pm 
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andand wrote:
I have started to solve the corners. It wasn't hard till I ended up with one corner twisted. Is that possible?
/Andreas

Nope. This is why you need to glue down the caps.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 5:47 pm 
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Ok, thanks! I just didn't notice when it could have happened. But I see that some corners are really loose.


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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Apr 20, 2013 6:00 pm 
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andand wrote:
Ok, thanks! I just didn't notice when it could have happened. But I see that some corners are really loose.
I haven't had the time to sticker mine yet but I noticed in the process of jumbling and unjumbling that I couldn't avoid accidentally twisting the corner caps. Assuming you end up twisting them lots of times and totally randomly there is a 1 in 5 chance of the resulting configuration being solvable.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sun Apr 21, 2013 3:29 am 
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For repair actions (e.g. when you screwed up a setup reversing, remember there is no Undo button :wink: ):

A pure corner 3-cycle (I think Brandon showed it in the Bauhinia thread):

Konrad's notation:
commutator form: [[FDL:F],[L:[DBL':[BR':UR']]]] [3,7]
full sequence:[FDL, F, FDL', L, DBL', BR', UR', BR, DBL, L', FDL, F', FDL', L, DBL', BR', UR, BR, DBL, L'] (20)

Gelatinbrain:
commutator form:[[EJF:ADE],[IFJ:[LJK':[GHL':HCB']]]]
EJF, ADE, EJF', IFJ, LJK', GHL', HCB', GHL, LJK, IFJ', EJF, ADE', EJF', IFJ, LJK', GHL', HCB, GHL, LJK, IFJ']

Image

A triangle 3-cycle (from Bauhinia thread as well):

Konrad's notation:
commutator form: [[D':DR],[FL:[F:FR']]] [3,5]
full sequence: [[D', DR, D, FL, F, FR', F', FL', D', DR', D, FL, F, FR, F', FL'] (16)

Gelatinbrain:

commutator form: [[EDK':KDG],[FAE:[ADE:CDA']]]
full sequence: EDK', KDG, EDK, FAE, ADE, CDA', ADE', FAE', EDK', DGK', EDK, FAE, ADE, CDA, ADE', FAE'

Image

You can cycle the centre triangles back with a pure [[1:1],1] getting a pure 3-cycle of wide triangles.

These beasts may be hard to memorize, though :lol:

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sun Apr 21, 2013 3:50 am 
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Konrad wrote:
A pure corner 3-cycle (I think Brandon showed it in the Bauhinia thread):

Konrad's notation:
commutator form: [[FDL:F],[L:[DBL':[BR':UR']]]] [3,7]
full sequence:[FDL, F, FDL', L, DBL', BR', UR', BR, DBL, L', FDL, F', FDL', L, DBL', BR', UR, BR, DBL, L'] (20)

Gelatinbrain:
commutator form:[[EJF:ADE],[IFJ:[LJK':[GHL':HCB']]]]
EJF, ADE, EJF', IFJ, LJK', GHL', HCB', GHL, LJK, IFJ', EJF, ADE', EJF', IFJ, LJK', GHL', HCB, GHL, LJK, IFJ']

Hmm I'm not sure why I'd show a [3,7] when earlier today I found an obvious [7,1]. Perhaps I just missed it last time?

Here it is in short-hand: [[JEK':[JLI':[HIL':HCB']]],DKE'] which is [[1:[1:[1:1]]],1]

GB's notation: [JEK', JLI', HIL', HCB', LHI, JLI, JEK, DKE', JEK', IJL', LHI', HCB, LHI, IJL, JEK, DKE]
Konrad's notation: [DL', BL', B', UR', B, BL, DL, D', DL', BL', B', UR, B, BL, DL, D]

Also check it out on 2.1.4 since it has a neat effect there.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sun Apr 21, 2013 4:25 am 
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Nice find, Brandon :)
Here is a picture for it:
Image

Now, what about an improvement for a pure 3-cycle of wide triangles :wink: ?

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sun Apr 21, 2013 4:55 am 
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Konrad wrote:
Now, what about an improvement for a pure 3-cycle of wide triangles :wink: ?

The way they move makes them hard. There is no easy way to split one from the surrounding pieces without slice moves or anti-moves. The best I can find so far is [3,7]:

[EDK', DGK, EDK, EFA', ABC', ADE', EJF, ADE, ABC, FAE, KED', GKD', KED, FAE', ABC', ADE', EJF', ADE, ABC, FAE]

I'm pretty sure there is something shorter.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Mon Apr 29, 2013 6:06 am 
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Hi fellow Icosahedron sufferers,

Konrad wrote:
In my opinion, the problems with solving Eitan's Star are more on the practical level (getting used to setup moves and reverse them correctly.) The theory (i.e. finding commutators for the four piece types) will be not so hard for those who have mastered the Bauhinia.

Konrad is right, the Eitan’s star is pretty easy to find some sequences for, and it has only a few piece types, but it is the solving of the puzzle that is a huge visual and mental challenge.
bmenrigh wrote:
My first solve of a FTI was so satisfying and I hope others get a similar experience.
I share Brandon’s sentiments: In fact it was so satisfying that I put it on the shelf and vowed never to scramble it again (until next time). For me it was `visually` more difficult than Tom’s Multidodecahedron, but it wasn’t as punishing if you make a mistake (although with the Multidodecahedron I am yet to make a mistake, the Eitan’s Star is visually harder `throughout setups and sequences` to solve). I made numerous mistakes with the Eitan’s Star, mostly unpacking setups, although they are not catastrophic, they are definitely a nuisance. I did however sticker it to be difficult though: I dispersed every similar sticker colour to match faces within a twist in order to be confusing (and it was): I do recommend this though, because it increases the challenge (photo below vv).
Attachment:
Eitan's Star Stickering Demonstration.jpg
Eitan's Star Stickering Demonstration.jpg [ 1.08 MiB | Viewed 7974 times ]
I started with an accidental scramble, while initially searching for sequences. I had found only the simple [4,1] centre 3cycle, and a pure 3cycle (of 3 grouped pieces) with a Sune: that I noticed could be used impurely for Edges, or split to commute Wide Centres (as demonstrated below vv). I had been searching the puzzle a bit because I was intimidated by the nature of the way that it twists, I haven’t solved a FT Icosahedron before. So suddenly I was faced with a scrambled puzzle with very little information!

I decided to solve Corners first, which was easy enough > then Centres (which I knew I could do easily) > then use my Sune to commute Wide Centres, and lastly I eventually had to resort to Gelatinbrain to find a 3cycle for Edges (which I put below vv). The Sune, for Wide Centres, has the advantage of only twisting 2 faces so, while being a longer sequence, it does make it easy to keep track of your moves during the sequence. And practically, I could only place one Edge at a time in each 3cycle, for fear of messing up prior work, so Edges took a long time.

Method:
1. Corners.
2. Centre (pure [4,1]): [FAE, CDA', FAE', CDA, KED', CDA', FAE, CDA, FAE', KED] Of course a [3:1] is possible but I prefer performing the more symmetrical [4,1].
3. Wide Centre Sune (impure [8,1]): [(FR UFL FR’ UFL)x2 F (UFL’ FR UFL’ FR’)x2 F’] = [CDA, AFB, CDA', AFB, CDA, AFB, CDA', AFB, ADE, AFB', CDA, AFB', CDA', AFB', CDA, AFB', CDA', ADE']
4. Edge (pure [5,1]): [(FL FR F FR’ FL’) L’ (FL FR F’ FR’ FL’) L] = [FAE, CDA, ADE, CDA', FAE', IFJ', FAE, CDA, ADE', CDA', FAE', IFJ]

On Gelatinbrain I noticed that the Edge sequence could be used for Wide Centres too (to minimise learning different sequences), but this disturbs Centres, and would require placing the Centres later (which it’s probably better to place them last anyway- considering: if you mess up with Wide Centres or Edges (which is where most of my mess ups were) you don’t have to redo the Centres continually for no reason. The drawback of doing Centres last is that sometimes they are visually helpful with completing sequences and unpacking setups.

Wide Centres -using Edges sequence- (impure [5,1]): [(FL FR F FR’ FL’) DL (FL FR F’ FR’ FL’) DL’] = [FAE, CDA, ADE, CDA', FAE', EKJ, FAE, CDA, ADE', CDA', FAE', EKJ'] And solving order: Corners > Wide Centres > Edges > Centres.

Final thoughts: Seems easy enough on face value, but tackling it physically: It’s really tough. I went straight into a piece type solve and if I can muster the mental fortitude to scramble it again I think I’ll consider more of a block building start.

Cheers,
Burgo.

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Last edited by Burgo on Mon Apr 29, 2013 4:22 pm, edited 1 time in total.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Mon Apr 29, 2013 12:01 pm 
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Burgo wrote:
...Final thoughts: Seems easy enough on face value, but tackling it physically: It’s really tough. ....Cheers,
Burgo.
Wow, this statement coming from you ... :o Congratulations!!!

I'm glad that I have still some time until my birthday to summon up my courage to scramble it. :lol:

Yesterday, I put stickers onto mine. I mixed and merged the mf8 stickers with those from Olivér. My goal was to make a nice colour scheme and one I can memorize, if I ever want to do the wide triangles first.
Maybe, it is visually too confusing, but I'll try to do those 60 pieces using a simple [1,1] commutator in step 1.

I'll let you know more after June 13th :wink: (And I'll get my left eye operated mid May. Maybe, this helps too enhancing my visual capabilities :roll: )

EDIT:
Burgo wrote:
....4. Edge (pure [5:1]): [(FL FR F FR’ FL’) L’ (FL FR F’ FR’ FL’) L] = [FAE, CDA, ADE, CDA', FAE', DCG', FAE, CDA, ADE', CDA', FAE', DCG]....
I guess this should be:
4. Edge (pure [5,1]): [(FL FR F FR’ FL’) L’ (FL FR F’ FR’ FL’) L] = [FAE, CDA, ADE, CDA', FAE', IFJ', FAE, CDA, ADE', CDA', FAE', IFJ]

The TP notation part seems correct. I cut and pasted the Gelatinbrain part into Gelatinbrain and it did not do the expected.

BTW, I know conjugates as [X:Y] and commutators as [X,Y].
Probably, some other ":" should become "," above?

alaskajoe, you have used [X.Y] for conjugates above. Have you done this intentionally or was it a typo?

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Mon Apr 29, 2013 4:38 pm 
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Hi Konrad,

Thanks for keeping your eye on my text, the mistake I made was due to me copying and pasting my sequence for Wide Edges, and then manually changing the Y part (I used the `other face with the same colour` on Gelatinbrain's 10 colour scheme by accident :roll: ). Sometimes relying on visual things can cause mistakes too!

It's a good idea to place the Wide edges first with a [1,1] as suggested by Alaskajoe, but I would find it very tedious to remember a full 20 colour scheme, it will be interesting to see how you go. Remember too: When I begin solving Wide Edges with the Sune method, I can place a number of pieces with just applications of Sune directly (and a setup), but it pretty quickly becomes a bit tight and it's difficult not to knock some out with setups. It might be a handy way to work with some block building though.

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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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Tue Apr 30, 2013 6:34 pm 
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Hello fellow Icosahedral Puzzle Enthusiasts. I'm very keen to participate in this thread and should have had a big head-start as I've been solving the Radiolarian 3 for a few months now. In fact my notation is so close to Konrad's that it is just a matter of changing a few letters. This makes sense as I based my icosahedron notation on the Twisty Puzzle Dodecahedron notation. HOWEVER there is one huge issue and I have only just come to terms with it... my notation and all my algorithms for both the Radiolarian 3 and Eitan's Star use a front face that has the central triangle with the base UP (V shape instead of A shape) :mrgreen:. Yes, my layout is completely backwards from Konrad's! :shock: Konrad's "B" is my "F". I've had some time to think about it and it's not so bad... it could also be viewed as being "upside down", which presents a reasonable pathway to convert my algorithms to the current notation.

I'll be catching up over the next couple of weeks and perhaps I will still be able to contribute something useful. The Radiolarian 3 was one of the most satisfying solves since I've been in this hobby, and I think Eitan's Star will be a similar experience.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Tue Apr 30, 2013 8:16 pm 
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Regarding "point up" or "point down" orientation of the top face, I stopped paying attention to such things a long time ago. I used to have a canonical orientation for the Megaminx. I memorize all of my commutators visually so I can do them relative to whatever orientation the puzzle is in. Whenever I need to deal with a notational matter I just use Gelatinbrain's program and copy and paste. I think you should just stick with whatever orientation and notation works for you and eventually you'll get used to other ways too.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Wed May 01, 2013 6:37 am 
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Pete the Geek wrote:
Hello fellow Icosahedral Puzzle Enthusiasts. I'm very keen to participate in this thread and should have had a big head-start as I've been solving the Radiolarian 3 for a few months now. In fact my notation is so close to Konrad's that it is just a matter of changing a few letters. This makes sense as I based my icosahedron notation on the Twisty Puzzle Dodecahedron notation. HOWEVER there is one huge issue and I have only just come to terms with it... my notation and all my algorithms for both the Radiolarian 3 and Eitan's Star use a front face that has the central triangle with the base UP (V shape instead of A shape) :mrgreen:. Yes, my layout is completely backwards from Konrad's! :shock: Konrad's "B" is my "F". I've had some time to think about it and it's not so bad... it could also be viewed as being "upside down", which presents a reasonable pathway to convert my algorithms to the current notation.

I'll be catching up over the next couple of weeks and perhaps I will still be able to contribute something useful. The Radiolarian 3 was one of the most satisfying solves since I've been in this hobby, and I think Eitan's Star will be a similar experience.
Is the Radiolarian 3 not logically more or less identical (one more piece type)?

Regarding the notation: We had one already for the Vertex Turning Dodecahedra, so, it seemed quite obvious to take the same for FT Icosahedra. (Actually, I used a different one before, but thought it to be wiser using the same.)
I think that notation is needed at least for sharing move sequences. One cannot always make a video :wink: and I, as an example, have no video equipment at all. (Maybe, I should get one for taking videos of my granddaughters :wink: )
If everybody has access to Gelatinbrain, the Gelatinbrain notation is fine. I have the impression that this is not the case for everybody .

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Mon May 13, 2013 10:25 am 
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I don't have much commutator-related to add on top of what Brandon and Joe have already posted. I have basically the same set of commutators. However, I would like to make the recommendation of solving the first hemisphere of the puzzle with F2L style methods before solving the second half with whatever piece-order you prefer. IMO this method makes the solve more fun and less tedious.

I'm sure there are many specific methods of doing this, but here's a rough outline of one possible approach:

Attachment:
FTI1.png
FTI1.png [ 25.66 KiB | Viewed 7628 times ]

These first 4 sets of pieces aren't that complicated, but this is my recommended order.

Attachment:
FTI2.png
FTI2.png [ 25.19 KiB | Viewed 7628 times ]

This second 4 sets are a little more difficult, so here are some simple conjugates that you can use. First assemble the appropriate pair of pieces using the top hemisphere as your workspace, and then insert them with the following:

Grey: (just an individual edge, not a pair)
GB Notation [CDA,FAE,CDA',FAE',CDA']
Konrad Notation [FR,FL,FR',FL',FR']

Tan: (mirror image of Grey alg)
GB Notation [FAE',CDA',FAE,CDA,FAE]
Konrad Notation [FL',FR',FL,FR,FL]

Grey-Blue:
GB Notation [FAE,AFB,FAE,AFB',FAE']
Konrad Notation [FL,UFL,FL,UFL',FL']
(And the mirror image of this alg)

Inserting the lime pieces should be easy enough...

Personally, instead of finishing all the Grey pieces before moving on to the Tan pieces and so on, I prefer working my way around the puzzle, solving the pieces in that order only locally. This leaves you some additional workspace for pairing pieces. Again, there are many ways of completing the first hemisphere without commutators. This is just one possible approach.

(I apologize if the colors I used are difficult to see... I was trying to pick colors that were far enough away from the GB color scheme, but perhaps I didn't do such a great job...)


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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Wed May 15, 2013 4:35 am 
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I've had almost nothing to do with TPs for a number of weeks now, due to something else un-TP-related. But Eitan's Star came my way late last week.

I've had some adventures with it and was really hoping to first post here about the block-building hemisphere method. DKwan beat me to it. My approach was very similar to his.

I ended up spending way more time than I've had on this, and made a blog post about it all. Konrad and Burgo get a cameo appearance in it. I also made an unboxing video for anyone who's interested (which also makes a cameo in the blog post).

I hope it helps show the approach a little more, and also entertains you!

Blog Post: My Adventures With Eitan's Star
Unboxing Video: http://www.youtube.com/watch?v=tL1t172ud84

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Wed May 15, 2013 11:03 am 
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Seems like you had quite the adventure rline, your blog post was an entertaining read that I'm sure many of us can relate to.

I previously used a block-building approach to help solve the functionally equivalent 1.2.3 (Eric Vergo's Pentagram), so I already had a good idea of what I was doing going into this puzzle. The small difference is that when doing blockbuilding in GB, I use a more organic approach to minimize my move counts and will often assemble larger clusters of pieces at a time, but for the physical version there is no move counter, so instead it helps to follow a structured method that is easier to apply without getting lost. That's why I came up with the specific method I outlined.

You used a much different order for blockbuilding than I did, and at a glance it seems your order (for doing centers before corners) may be more efficient, because it only requires one [3:1] while my outline requires 2.

Attachment:
File comment: Rline's Order
FTI3.png
FTI3.png [ 34.26 KiB | Viewed 7512 times ]

Following the order from your blog (with some tweaks), I've come up with this. Starting with the black part, leave those 5 edges as gaps to be filled when you insert the corners above them later. Then, following this order of piece-pairs, you can insert all of them with simple [1:1] conjugates except for the lime and light-red ones which require a [3:1].

GB: [ADE,AFB,ABC,AFB',ADE']
Konrad: [F,UFL,UFR,UFL',F']
(and it's mirror image)


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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Wed May 15, 2013 4:04 pm 
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DKwan wrote:
Following the order from your blog (with some tweaks), I've come up with this. Starting with the black part, leave those 5 edges as gaps to be filled when you insert the corners above them later. Then, following this order of piece-pairs, you can insert all of them with simple [1:1] conjugates except for the lime and light-red ones which require a [3:1].

Yeah, I tried to make the blog at least be honest about the fact that this thing is not easy!

Anyway, I agree thoroughly with you about the order of things. My order in the blog was the order I did things as I was going. But if I had to now do it efficiently as possible (I define efficiently as "simple for me", which means higher move counts don't bother me so much), I would do

1. The blockbuilding method you and I have used, with your tweaks above (but with the minor change that I found I needed to do the pale yellow centers after the light blue corners, not the other way around).
2. Upper triangles
3. Upper Corners
4. Upper Edges
5. Upper Centers

This is mainly because my centers alg is pure, and simple, and it's easy to finish with them.

Attachment:
es-lower half sequence.jpg
es-lower half sequence.jpg [ 36.16 KiB | Viewed 7443 times ]


Attachment:
es-upper half sequence.jpg
es-upper half sequence.jpg [ 32.59 KiB | Viewed 7443 times ]


Anyone else tackling this currently?

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Last edited by rline on Wed May 15, 2013 6:46 pm, edited 1 time in total.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Wed May 15, 2013 5:42 pm 
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rline wrote:
Anyone else tackling this currently?

I have been lurking in this thread since the beginning with a certain sense of awe!

I really want this puzzle because it looks so awesome and is the first icosahedron to be mass produced. But I seriously doubt I have the skills to solve it and hesitate to spend $100 on something I will scramble once and never be able to unscramble!

Damn! Indecision is a terrible thing! :shock: :shock:

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Thu May 16, 2013 12:49 am 
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rline wrote:
...I hope it helps show the approach a little more, and also entertains you!

....
What an adventure and what an entertainment. :lol: I read it in the hospital waiting for my surgery and your Blog cheered me up..
If everything goes well my adventure shall start on June 13th.

OK, I admit that it was a kind of a deal with my longsuffering wife, that she has confiscated Eitan's Star and made it a birthday gift :lol:
Quote:
...but that I still have a wife. I assure you it's true. She is without a doubt the most longsuffering wife in the world.
Maybe, Burgo's and my wife will question the "without a doubt" :lol:

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Thu May 16, 2013 3:30 am 
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My wife is identical... maybe worst...
Actuyally, it seems that they are all the same... :?


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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Thu May 16, 2013 3:31 am 
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Konrad wrote:
Quote:
...but that I still have a wife. I assure you it's true. She is without a doubt the most longsuffering wife in the world.
Maybe, Burgo's and my wife will question the "without a doubt" :lol:

Don't forget the present Mrs S! She of the high power laser stare and the cat-o-nine tails tongue!! :shock:
She has watched me collect 670 puzzles in 3 years and spend an obscene amount of money on what she considers toys! Somehow she puts up with it as long as the steady stream of shoes and designer handbags keeps heading her way! We're up to 19 Mulberry bags now!!! :shock: :shock:

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Fri May 17, 2013 7:37 am 
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Well, I'm still in the hospital, but the surgery went well. So I did a little project with one eye :) :
I think that it became clear from earlier posts and rline's Blog, that the setups for edge 3-cycles can be tedious and dangerous (to screw up the reversing of setups). So, I thought I would prepare a set of 3-cycles that I can easily memorize and that may enable me to cut down the number of setup moves:

I started with a [5,1] commutator (actually a [[1:[1:]],1]) (Gelatinbrain) [[ABC':[CDA':FAE]],DCG]=[ABC', CDA', FAE, CDA, ABC, DCG, ABC', CDA', FAE', CDA, ABC, DCG'] or [UFR', FR', FL, FR, UFR, FDR, UFR', FR', FL', FR, UFR, FDR']. I permuted this sequence and made any resulting 3-cycle that produces a different pattern a [5,1].

So, I got basically 8 different operations, with the mirrored and inverse versions 32.

Image

Here is a table with 16 of them including the written commutators, I left out the mirrored versions:

Image

I think that I can memorize all these variants, because I see all pieces involved on the front hemisphere and the construction of the commutator is easy to understand. I do not think that I can invent them on the fly, but memorizing them seems OK. If I neglect the mirrored versions, only 4 faces are involved and either FDR or FL are the "1" move. I'll see how theory meets practice :wink:

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Fri May 17, 2013 8:08 am 
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Quote:
So I did a little project with one eye :) :

Just imagine how many you would have found if you'd had both eyes available. :shock: :lol:

(I think this may tip Kevin over the edge...)

As usual, Konrad, some great pictures. My initial reaction with this sort of thing is always that one commutator is hard enough to remember, and so I'm very interested to hear whether these serve you well when you solve the puzzle in practice.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Fri May 17, 2013 11:25 am 
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rline wrote:
... My initial reaction with this sort of thing is always that one commutator is hard enough to remember, ....
May I insist that I talk about just one basic commutator: [[UFR':[FR':FL]], FDR] :)

This table wants to elaborate the commonality of the eight variants:

Image

I have skipped all the inverse / mirrored versions.

You may ask: Doesn't look the common formula 5. to 8. a bit different, how did you get there?

We start with [[ABC':[CDA':FAE]],DCG]= [ABC', CDA', FAE, CDA, ABC, DCG, ABC', CDA', FAE', CDA, ABC, DCG' ] =
[UFR', FR', FL, FR, UFR, FDR, UFR', FR', FL', FR, UFR, FDR'] = [[UFR':[FR':FL]],FDR].
If we start with move #4 we get:

[[CDA:[ABC:DCG]],FAE']= [CDA, ABC, DCG, ABC', CDA', FAE', CDA, ABC, DCG', ABC', CDA', FAE]=
[FR, UFR, FDR, UFR', FR', FL', FR, UFR, FDR', UFR', FR', FL]=[FR:[UFR:FDR]],FL'] which is 7. in my table.

I hope this explains why I'm talking about a single commutator producing 32 variants!

Isn't this nice? :)

BTW, for things like this I highly recommend Brandon's sequence utility

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Mon May 20, 2013 9:09 pm 
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Konrad wrote:
Is the Radiolarian 3 not logically more or less identical (one more piece type)?
That's what I expected and I have finally confirmed that my Radiolarian 3 algorithms work fine on Eitan's Star. In fact there is nothing stopping me from scrambling it up and solving it... :mrgreen:

Konrad, that is a very interesting approach to the corner points and with your powers of organization, I can see it being very effective. By comparison my approach is minimalist, necessitated by certain limitations to my cognitive abilities. I use a slightly longer algorithm that 3-cycles corner points entirely on the front of the puzzle. I have a table which lists four variants of the algorithm - clockwise/counter-clockwise and mirrors. With these four variants and a few short setup moves, I feel perfectly equipped to solve the 60 corner points. When I was solving the Radiolarian 3, I found that I could safely unwind setup moves with 3 steps; any more and it becomes dangerous. If I really must move a corner point from further away than I can reach with 3 setup moves, I will just apply the algorithm to move the piece into reach.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Mon May 20, 2013 9:42 pm 
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Quote:
When I was solving the Radiolarian 3, I found that I could safely unwind setup moves with 3 steps; any more and it becomes dangerous.

That is so true on eitan's star. It's a nightmare if the concentration wanes.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Mon May 20, 2013 9:52 pm 
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rline wrote:
Quote:
When I was solving the Radiolarian 3, I found that I could safely unwind setup moves with 3 steps; any more and it becomes dangerous.

That is so true on eitan's star. It's a nightmare if the concentration wanes.

I think I'm one of the worst at undoing setup moves but I have no trouble with Eitan's Star because it's so shallow-cut. I can usually undo 6+ without too much concentration. Granted I shouldn't be doing 6+ in the first place but it isn't a problem.

The same can not be said for me and the Pentultimate or Master Pentultimate. My limit there is <= 3 without great concentration.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Tue May 21, 2013 5:22 am 
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Well a couple of things.

First, I just did a little experiment. I jumbled the star like crazy (partly because it kept jumbling while I was trying to unjumble it) and then solved it after returning to normal shape. What surprised me was that there were no strange things at all. It solved normally. Is this normal? Or was I extraordinarily lucky? It seems strange to me that there'd be no difference in the solve (similar to how on the helicopter pieces change orbits), but I don't understand jumbling enough to know for sure.

Second, I've just finished uploading my solve videos for the puzzle. I thought I would put my method here and then give links to the videos. My method is

Solve Method
1. Solve lower half of the puzzle, using simple turns and things like EPS
[The rest obviously pertains to the upper half]

2. Solve wide triangles, using U' UR U UR' and similar (just the EPS for cubes)

3. Solve corners, using U UR U' UL U UR' U' UL and a downward pointing triangle as the "Up" face (just the CPS). This is impure and moves edges as well.

{I found a nice corner twister to twist one corner anticlockwise 2 spots and another clockwise 2 spots. It's
(U UR U' UL U UR' U' UL) B' (U' UL' U UR U' UL U UR') B}

4. Solve edges, using [FDL' FL' FR FL FR' FDL FL' FR FL FR' ] x 2 and an upward pointing triangle as the "Front" face (just the CPS). This is impure and moves centers as well. (This is an adaptation of Burgo's incredibly cool sequence from the Bauhinia, that I never understood how he found it but loved it anyway.)

5. Solve centers, using F FDR F' FDL' F FDR' F' FDL and an upward pointing triangle as the "Front" face (just the CPS). This is pure.

This method displaces some centers done in the 1st stage while doing edges, but the centers are so simple it's worth it. There's almost nothing to remember with it and the only "difficult" sequence is super-easy to get a handle on.

I have to say I feel pretty good at having been able to conquer Eitan's star. It's a hefty puzzle and seriously challenging.

Some Videos
Written blog: http://twistypuzzling.blogspot.com/2013/05/eitans-star.html

Part 1 (lower half)
Part 2 (triangles)
Part 3 (corners)
Part 4 (edges)
Part 5 (centers)

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Tue May 21, 2013 9:26 am 
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rline wrote:
I jumbled the star like crazy (partly because it kept jumbling while I was trying to unjumble it) and then solved it after returning to normal shape. What surprised me was that there were no strange things at all. It solved normally. Is this normal? Or was I extraordinarily lucky? It seems strange to me that there'd be no difference in the solve (similar to how on the helicopter pieces change orbits), but I don't understand jumbling enough to know for sure.

That's correct. Jumbling on this puzzle doesn't change anything. No new states can be reached (when the puzzle is back in icosahedral shape).

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Tue May 21, 2013 9:48 am 
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rline, all the content you've produced for Eitan's Star (unboxing, review, tutorial, blog posts, etc.) is amazing! Thank you so much for all of this!

-Eitan

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Tue May 21, 2013 4:13 pm 
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pirsquared wrote:
rline, all the content you've produced for Eitan's Star (unboxing, review, tutorial, blog posts, etc.) is amazing! Thank you so much for all of this!

-Eitan

I'd like to say it's been a pleasure...Instead, I'll say that pleasure and pain have never been so close together :lol:

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Wed May 29, 2013 2:19 pm 
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I just realized I should be thanking everyone who contributed to this thread. Brandon, Konrad, alaskajoe, Burgo, Pete, DKwan, rline. You guys all rock.

One of my goals for the summer is to learn how to solve this beast of a puzzle. This thread and the videos Brandon made a year ago should get me there.

-Eitan

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sun Jun 09, 2013 2:16 pm 
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Finally, I have some time to solve Eitan's Star!

I started exactly like I would solve the Radiolarian 3... except that there are no edges, which makes it surprisingly different. After completing the first step (wide triangles) I've been looking through the thread for ideas on how people were getting the colour scheme. I am interested to see the new algorithm for the wide triangles and the corners-first approach. It makes sense for this puzzle, though I think that the wide-triangles-first approach is efficient and will get easier over time as experience with the colour scheme builds.

For my solve, I just assembled the wide triangles on faces by referring to the corners. In some cases, I inserted the corners to help me visualize things... it is time-consuming because the short algorithm I use for the wide triangles moves the corners.

Here are two views of the puzzle with the wide triangles done - and you can see where I put in a few corners along the way:
Attachment:
Eitan's-Star-Solve-1-Small-Triangular-Centres_sm.png
Eitan's-Star-Solve-1-Small-Triangular-Centres_sm.png [ 130.84 KiB | Viewed 6700 times ]


Here is a composite of the four main algorithms I use:
Attachment:
Algs-Comp4-Annotated_sm.png
Algs-Comp4-Annotated_sm.png [ 270.7 KiB | Viewed 6700 times ]

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Tue Jun 25, 2013 4:14 pm 
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Yesterday, I started finally to solve Eitan's Star.
Some may remember that I got it as a birthday gift time shifted and afterwards I was very busy with other things (e.g. PAW :wink: )
Well, it was as I had expected: When theory meets reality things are not so easy, anymore :roll:
First of all, turning the faces freely for breaking the puzzle in is something different than doing real move sequences.
I do not know, if others have the same problem: Whenever a puzzle catches seriously during a move sequence, it is hard for me not to loose concentration. So, I screwed once pretty early. That wasn't a big loss, because I had not yet solved much. Then everything went on as planned for a while.
I solved 1. wide triangles, 2. corners, 3. centres 4. edges
After the first few edges I took this snapshot:

Image

I used a fair subset of the edge [5,1] cycles shown above. That wasn't bad. I think that I never needed more than two or three setup moves, sometimes 0 or 1.
I paused for a while and continued today. As I had feared, in one split of a second I lost concentration, made a wrong turn, thought I remembered what it was and tried to correct it: Bang, it became worse.
OK, I think I'll read rline's story again to get some consolation.

I started over again, getting back to step 3 wasn't so much work, but the edges work was mainly back to a few solved.
I'll take my time and will try not to hurry.
My personal opinion:
1. This is a very hard puzzle, not in theory, but in practice.
2. It needs some time to get used to the movement of pieces and to see in your mind how the necessary setup moves have to be done.
3. Catching of pieces is not really bad, but it can cost you sometimes your concentration.
4. I guess that the edges cycles need a lot of automating to avoid a failure during such a long time. When you solve per piece type a few edges only are correct. So expect, that more than 50 have to be placed (I'm happy enough to place just one per cycle. BTW, I do not solve the edges in any specific order. I just look around for an opportunity for a 3-cycle that does not require many setup moves.
5. This puzzle needs a lot of stamina and concentration!!!


So far, the usual suspicious only have posted here about solving a physical Eitan's Star (Burgo, rline and Pete).
I recollect from Burgo's and rline's post that they felt a bit similar: Pleasure and pain are close together, as rline has expressed it.
Eitan, where is the Undo button???

If I can ever solve this thing completely, it will be some relief (and I'm pretty sure that I'll be at 67 the oldest solver of Eitan's Star then :lol: ). If not, I'll have to change my collection rule: (Old?): Buy new puzzles only, if you have solved all you have got so far.

The Multi Dodecahedron was easier and the Petaminx was a piece of cake compared with Eitan's Star! :wink:
Just my opinion.

EDIT June 26th, 2013: I have solved a few more edges and I'm counting 28 to go. I never needed more than two setup moves. The drawback is that I use 32 move sequences (counting all mirrored / inverse). They are very much related, but nevertheless it takes quite some concentration not mixing them :roll:
Image
I'll continue slowly solving some edges per day.

EDIT June 27th: Some Progress:
Image
Slowly I'm getting the hang of it and it doesn't feel so risky making a fatal error.
But you never know: Still 12 to go! (So far, I needed never more than three setup moves.)

EDIT2 June 27th: Wow, I did it! I did it!

3 edges left over:
Image
After 4 setup moves (I needed never more than 3 before) - reoriented in space:

Image

Solved
Image

As you can see on the yellow face, the nice "Eitan" signature is no longer visible. :(

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Thu Jun 27, 2013 2:51 pm 
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Yeah, I have finished it today! Please, see some more details above.
At the end, I had a screw count of 2.
The catching is almost completely gone and I got so familiar with my edge sequences that I felt not so much danger of loosing control.

Instead of my own closing remark I want to quote what Burgo wrote on April 29th above:
Burgo April 29th wrote:
Hi fellow Icosahedron sufferers,

Konrad wrote:
In my opinion, the problems with solving Eitan's Star are more on the practical level (getting used to setup moves and reverse them correctly.) The theory (i.e. finding commutators for the four piece types) will be not so hard for those who have mastered the Bauhinia.

Konrad is right, the Eitan’s star is pretty easy to find some sequences for, and it has only a few piece types, but it is the solving of the puzzle that is a huge visual and mental challenge.
bmenrigh wrote:
My first solve of a FTI was so satisfying and I hope others get a similar experience.
I share Brandon’s sentiments: In fact it was so satisfying that I put it on the shelf and vowed never to scramble it again (until next time). For me it was `visually` more difficult than Tom’s Multidodecahedron, but it wasn’t as punishing if you make a mistake.....

Final thoughts: Seems easy enough on face value, but tackling it physically: It’s really tough. I went straight into a piece type solve and if I can muster the mental fortitude to scramble it again I think I’ll consider more of a block building start.

Cheers,
Burgo.
Yes (sigh), I was right and yes, I agree that the Multi Dodecahedron was easier.
(Not many here will have their own opinion about the two :) )

I'm not sure, if my marriage could survive another scramble and solve :roll: :lol:

Maybe, others want to share their experiences with Eitan's Star, too?
Congratulations to everybody who has won this fight!

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Thu Jun 27, 2013 4:16 pm 
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I'm super-glad you shared your solving experiences Konrad. It seems like basically all of us who have (finally) solved it have found it a bumpy ride, to say the least. I think it's important that great solvers such as you and Burgo post about how difficult certain aspects of some puzzles are, because otherwise, some may get the impression that solving puzzles is always easy. That's why I made my Adventures blog post. I'm not a great solver, more of a determined getting-better solver, but I wanted people to know that it nearly killed me. :lol: And yet, a day later, I'd scrambled it again. Glutton for punishment.

I will say that the more you do this puzzle, the easier it gets. That's probably true for all puzzles, but it's especially helpful for this one which is so difficult. I'd love to know (along with you) who has actually solved the physical puzzle at least once. So far, I know of Burgo, you, me, Pete (I think?). I know of at least one other person who may not yet be a TP member but who has solved it. Seems a fairly small club?!

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Thu Jun 27, 2013 5:15 pm 
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Well, I've finished the first half of the puzzle, following rline's awesome tutorial. Seeing as parts 2, 3, and 4 of the tutorial are each as long as part 1 (30 minutes!), I am probably in for quite a rough ride.

Thanks to everyone who is posting their experiences!

-Eitan

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Thu Jun 27, 2013 5:19 pm 
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rline wrote:
I will say that the more you do this puzzle, the easier it gets. That's probably true for all puzzles, but it's especially helpful for this one which is so difficult.
I agree that with experience these puzzles get easier and I had a huge head-start from the Radiolarian 3. The lack of edges made positioning the wide triangles a bit challenging - like solving a Void Radiolarian 3 - but it was more a learning experience than anything. Otherwise, it went like clockwork. I used algorithms exclusively because I'm not naturally good at block-building on icosahedral puzzles. My Eitan's Star turns very well and I look forward to many pleasant solves in the future:
Attachment:
Eitan's-Star-Solve-All-Steps-Comp_sm.png
Eitan's-Star-Solve-All-Steps-Comp_sm.png [ 837.91 KiB | Viewed 6383 times ]

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Thu Jun 27, 2013 5:39 pm 
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rline wrote:
I'm not a great solver, more of a determined getting-better solver

OMG! What does that make me?? :shock: :shock:
In fact what does that make anyone who isn't one of the magical 5 solvers?

rline wrote:
but I wanted people to know that it nearly killed me. :lol: And yet, a day later, I'd scrambled it again. Glutton for punishment.

That's a bit like me and the Bauhinia dodecahedron! I promised never to scramble it again but I've done it 5 times now!

Still unsure whether to buy the Eitan's star because I very much doubt I could solve it after reading Rline's harrowing experience and everyone else's struggles. I'm but a mere newbie compared to you lot!

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Thu Jun 27, 2013 5:58 pm 
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Puzzlemad wrote:
That's a bit like me and the Bauhinia dodecahedron! I promised never to scramble it again but I've done it 5 times now!

Still unsure whether to buy the Eitan's star because I very much doubt I could solve it after reading Rline's harrowing experience and everyone else's struggles. I'm but a mere newbie compared to you lot!
Eitan's Star is practically a face-turning version of the Bauhinia and, as an added bonus, you can untuck your thumb! :mrgreen:

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Fri Jun 28, 2013 2:43 am 
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Puzzlemad wrote:
...Still unsure whether to buy the Eitan's star because I very much doubt I could solve it after reading Rline's harrowing experience and everyone else's struggles. I'm but a mere newbie compared to you lot!
Kevin, you definitely have to get Eitan's Star. First it is such a beauty, second: Somebody who has solved a Bauhinia 5 times is predestined to become a honoured member of the (exclusive ?) "Eitan's Star solver club".
Don't say you are a newbie anymore. A 5 times Bauhinia solver will get the honour needle of said club :lol:


Just to elaborate a bit on Pete's statement
Quote:
Eitan's Star is practically a face-turning version of the Bauhinia
,in the picture below I elaborate a bit the close relationship of Eitan's Star =DEFTI and the Bauhinia:

Image

As you can see Eitan's Star has even less pieces than the Bauhinia. The difference comes from 30 middle edges on the Bauhinia (do not exist on the Star) versus 20 centres on the Star (do not exist on the Bauhinia).
In my opinion, the Bauhinia is quite a bit easier due to the 5 identical centre triangles which are unique edges on the Star and the Bauhinia centres (corners on the Star) having no orientation.

BTW, so far I'm counting seven members of "Eitan's Star solver club".
Burgo, rline, DKwan, Pete, Konrad, Bendup, Dreiser, Eitan (pirsquared)
(Bendup is rline's "at least one other person who may not yet be a TP member but who has solved it".)

BTW, rline, I do not view myself as a "great solver". You have certainly better visual capabilities than me - and make phantastic videos. (I have to admit that I did not look at your Eitan's Star tutorial so far. Your blog was great fun. I knew after it, that I would screw up the Star at least once. I'm happy with my screw count of 2.)
"Determined" is OK with me too and I can be pretty concentrated for some time - if my wife doesn't interrupt me too often with the trivialities of life :lol:

EDIT: I have edited the list of solvers of a physical Eitan's Star above (see DKwan's post below).
DKwan is on my short list for "great solvers", anyway :)

EDIT2: I added Bendup and Dreiser to my list (see their and rline's posts below)

EDIT3: I added Eitan to the list and will maintain a list of the known solvers in the first post of this topic.

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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Fri Jun 28, 2013 5:37 am 
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rline wrote:
I'd love to know (along with you) who has actually solved the physical puzzle at least once.

Just to clarify, I had already solved my physical Eitan's Star twice before making my blockbuilding post. Definitely two of the longest physical solves I've ever done, but certainly very rewarding.

I think this may be the only physical puzzle I own that I have not actually solved on GB as well!


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 Post subject: Re: How to solve Eitan's Star?
PostPosted: Sat Jun 29, 2013 3:40 am 
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rline wrote:
I'd love to know (along with you) who has actually solved the physical puzzle at least once. So far, I know of Burgo, you, me, Pete (I think?). I know of at least one other person who may not yet be a TP member but who has solved it. Seems a fairly small club?!


My first post to twisty puzzles is to add my name to the club roster of the solvers of the star. I mostly followed the ideas in the videos by Rline.

I cannot really add anything of value that has not already been said about this puzzle. Just maybe that I would greatly encourage potential solvers to take time to properly lube this puzzle. Please don't misunderstand me: I am not saying it turns badly ,but its a very complicated puzzle mechanically and easy to lock up. At my age the memory is not what it used to be so if I am in the middle of a 20 step algorithm and have to jiggle a few faces to unlock a turn its easy to forget where I was. Added to this is the visual complexity of the puzzle so when I get lost in my train of thought its near impossible to determine visually where I was in the algorithm.

Other than the above comment all I can say is I love this puzzle and plan to solve it a third time in the near future.


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