Double Escape and Crazy Elephant Dance

When I was down at NYPP, Brett Kuehner was kind enough to give me Double Escape, which was Markus Götz's IPP26 exchange gift. It is a disentanglement puzzle, and Brett isn't a big fan of disentanglement puzzles, so he thought I might enjoy it. Thanks Brett!

Most of the disentanglement puzzles I have are of the 'all rigid' variety, such as these Dick Hess wire puzzles. The ones with a flexible component like rope can be pretty tricky and it is sometimes easy to get them all tangled up, so I have shied away from them somewhat. However, I really enjoyed Dinghy and Holey Bolt.

Double Escape is a cool idea: there are two objectives of varying difficulty. The dark ring on the right hand side is "easy" to remove (according to Markus), but the one on the left is more difficult because you are restricted by the length of the rope. It is an extension of his earlier design, Narrow Escape.

Since I'm not too familiar with this type of puzzle, even removing the easy ring took me about 30 minutes or so. Now that I know how to do it, it seems pretty easy, but at the time I remember being pretty puzzled.

Removing the second ring baffled me for quite a while. I left it on my end table and worked on it on and off for a few weeks. Usually I didn't spend much more than 10-15 minutes on it, so I think the total time is somewhere around 2-3 hours.

Since I tend to be better at solving puzzles in the morning, I decided to give it a shot this morning when my mind was fresh. Typically, I was only working on it after work, and work was pretty busy so I think my mind was a bit weary. Sure enough, after about 30 minutes I had figured it out!

The solution is quite cool: you really need to think about your strategy for removing the first ring and see how you can apply it to the second ring. Simply doing the same type of moves doesn't work, because of the length of the ropes, so you need to be a bit creative to find the space to remove it.

Markus rated it a 5-6 on a 1-10 scale in terms of difficulty, but I found it a bit harder than that. It really depends on your experience with a particular type of puzzle, I think. Overall, a great puzzle: it is a very nicely crafted puzzle with a nice finish. It is also fairly large and quite sturdy.

When browsing Markus's website, I noticed that he was also the designer of Crazy Elephant Dance, which is a trinary version of one of the puzzles that started my interest in puzzles, the Chinese Rings/Patience puzzle. Crazy Elephant Dance won an honorable mention in the 2005 Puzzle Design Competition at IPP25.

Its mechanism is similar to Spin Out (which is Chinese Rings with a different mechanism), but rather than having two positions for each disk (binary), there are three positions (trinary). This means that rather than doubling the number of moves with each additional disk, the number of moves triples! Well, the actual formula is more complicated than that, but it is close. In addition, unlike Spin Out, you can make wrong moves that leads to a dead end, so it is a bit tricker!

I had always wanted to give this puzzle a try, and Markus actually has a Java applet on his website that lets you try his puzzle online! It was a lot of fun, since the applet allows you to see how the mechanism actually works when you click the mechanism button. Definitely check it out if you haven't had a chance to try it before and enjoyed Chinese Rings.

Snowflake and Tri-Frame

Last weekend I was in Urban Outfitters (a clothing store that also sells a bunch of other random stuff) and noticed that they had a whole lineup of bamboo puzzles for $10 each. They are sold under the name "EcoGame" (they don't seem to have a website) and are imported by streamlinenyc.com from China. On the Streamline website they have the full set of puzzles shown, but they only seem to sell to retail customers. [Update: It looks like Puzzle Master is selling them now!]

From left to right, top to bottom are a Soma cube, a Hedgehog puzzle (not sure of the standard name), a Pagoda burr, a diagonal burr (with no key piece), a 24-piece Chuck puzzle (I think), Locked Nest, a rounded diagonal burr (same solution as the one above it), an assembly pyramid (non-interlocking), and Snowflake. As you can see, they make frequent use of the light/dark lamination for a pretty good effect.

I ended up buying two, the first of which was sold under the name Snowflake. When I tried it out in the store, I was unable to figure out how to take it apart, so I figured it would be a good challenge.

Unfortunately when I got it home and inspected it more closely, I discovered that it was pretty much just a fancy-looking version of the 9-piece Pagoda burr that they were also selling! I wasn't able to get it apart in the store because the fit was quite snug. The 9-piece Pagoda burr had such a loose fit that the piece that moves first wiggles around quite a bit. The tight fit makes it a bit harder, making it necessary to inspect the joints to figure out what you can move and how.

Still, it isn't a very difficult puzzle, I solved it in a few minutes. However, I did like their use of contrasting colors of bamboo. It gives the puzzle a nice appearance. Also, as I mentioned, the fit is actually pretty good considering it is a mass-produced puzzle. The pieces fit snugly together and the finish isn't bad. Overall, I thought it was a good buy for $10.

The second puzzle I purchased was sold under the name Tri-Frame. It is a design I recognized from Stewart Coffin's Puzzling World of Polyhedral Dissections which he named Locked Nest. However, rather than using hexagonal rods, they used dowels.

This one was given a 5/5 star difficulty rating, so I was hoping it would keep me busy for a while. Before I purchased it, I took it out of the box to see how good the fit was, and was happy to see that the  pegs were held in place fairly well.

When I got home, I took it apart and set myself to the task of putting it back together. I immediately noticed that although the fit seemed good when the puzzle was assembled, a stick going through a single hole did not have enough friction to stay in place: it was only when the structure started to come together that there was enough friction.

This made it quite a dexterity problem, because the rods kept slipping out as I was getting things arranged. Eventually I was able to start making progress. Figuring out the assembly itself was a bit tricky at first, since it is hard to figure out where to start. Once I got a few of the pieces in place it became a lot more obvious where the rest should go.

Overall, this was a fun puzzle and a good deal for the price, but I probably wouldn't recommend it due to the fit. I actually didn't like the light/dark lamination on this one as much as the others, it just looks a bit chaotic to my eye since the holes are not consistently drilled relative to the coloring.

Small Die Puzzle Box

I recently acquired a copy of Small Die, by Akio Kamei through eBay. It was brand new in-box for somewhat less than the Karakuri Club price, so I was pleased. It arrived a few days ago and I had a good time with it.

It looks like a die, with a number of spots on each side: one through six. I really had no idea how this one worked when I bought it, so I was eager to figure it out.

It became apparent that this was a hidden-mechanism type box rather than a sliding panel box, since nothing appeared to move at first. I fiddled with it for a little while, listening to the various sounds of the mechanism inside and did not make much progress. I set it aside for a while before returning to it.

During this second attempt an idea for how the mechanism might work occurred to me, based on some clues that I had uncovered. I tried testing out this idea a few different ways, and after a few attempts it opened! Woo hoo!

I think it took me about 15-20 minutes in total: this one is quite a bit tricker than most of the other Karakuri Club boxes I have tried so far. I got a bit lucky in my moment of inspiration: it could have taken quite a bit longer if that idea didn't occur to me.

The finish on this box is quite nice, though mine has a bit of a defect: one of the panels overhangs the edge slightly more than it should. Oh well! I got it for a good price. The fit of the panels is also quite good with a nice smooth action.

Overall, I thought this was a clever design, though there was one aspect that irked me a bit. I didn't like how even if you performed the correct sequence of actions, it might not open. It isn't random, but I can't really go into it any more than that without hinting at the solution. Still, I think this is definitely a neat puzzle!

At this year's International Puzzle Party, Akio Kamei is conducting a workshop where participants get to build this particular puzzle! I've signed up for it and I am interested to see how the mechanism actually works, since it isn't visible even when you open the box. I'm really looking forward to meeting him!