Puzzles from Brett

As I mentioned in my last post, Brett Kuehner very kindly gave me several puzzles when I visited his house. I have been playing around with them for the last week or so and enjoyed them very much.

The first one I tried when I got home was the Super Floppy Cube. This is a 3x1x1 twisty puzzle where you rotate the edges. Unlike a normal Floppy Cube where you can only rotate the edges 180°, on the Super Floppy Cube you can rotate an edge 90°. This enables it to form a number of interesting shapes, as you can see in the picture.

This puzzle was designed by Katsuhiko Okamoto and won the 2009 Puzzle of the Year Award (Puzzlers' Award and Jury Grand Prize) at Nob Yoshigahara Puzzle Design Competition at the International Puzzle Party.

I should mention that this puzzle is actually not licensed by Okamoto, it is a knockoff made in China, which is unfortunate. Currently, legitimate versions are not for sale, though they will be produced in 2010. Brett is planning to purchase the official version when it is available, since he knows it will be of high quality and support Okamoto's continued innovation.

The mechanism of this puzzle is quite fascinating. It seems almost impossible the way that a corner cube can seemingly attach itself to any edge cube. It is a fun toy just to play around with.

As a puzzle, it is actually quite easy. Due to the fact that you can rotate an edge 90°, you can move all the corners away from an edge and rotate that edge independently. This makes it pretty easy to solve, since (at least for me) orienting the edge cubes properly is the main challenge. Even an inexperienced puzzler should have a pretty easy time with this one, which I actually think is great. It would be a good introduction to this type of puzzle without being overwhelming. You can make it a bit more challenging by not permitting yourself to use the single-edge-twist move.

A puzzle designer named Richard Gain has set up a shop, microcubology, at Shapeways.com, a website that allows you to upload 3D models that are printed and mailed to you. In his shop, as you may guess from the name, he has a number of tiny interlocking cube puzzles. Interlocking means that the puzzle will not fall apart easily (unlike a soma cube). Since Shapeways charges based on volume (literally the volume of the model printed), these tiny cubes are quite reasonably priced. Brett gave me three of Richard Gain's puzzles: World's Smallest Puzzle Cube, Primary Gain, and Happiness Cube #20.

As you can see from the photo, World's Smallest Puzzle Cube is very small (7.5 mm across). Of course, you could make one smaller, but this is probably about as small as you would want to go to have a puzzle you don't need tweezers to assemble.

This puzzle is about as complex as you can probably get with a 3x3x3 interlocking cube, but I didn't find it too challenging. Still, it was a lot of fun playing around with such a tiny puzzle. Once I got the hang of putting it together I tried doing it with my eyes shut, it wasn't too bad! Overall, a great puzzle for the money: only $2 since it is so tiny!

Primary Gain is a bit trickier with four fairly complex pieces. It forms into a cube that could contain 8 of the tiny cubes above, to give you a sense of the size. This is still quite small at 1.6 cm per side.

This one didn't take me very long, but I enjoyed solving it. One of the pieces is pretty large and the other pieces are pretty irregularly shaped, so each of the other pieces can only really fit with the large piece in one way. I liked this, because it really cuts down on the trial and error involved.

The tricky part is getting all the pieces together at once, since they tend to get in each others' way. It takes three moves to remove the first piece, two moves to remove the second piece, and three moves to remove the third piece. This is a great little interlocking cube and the first one that Richard Gain designed (hence the name).

Happiness Cube #20 was designed by Sekoguchi Yukiyasu and reproduced by Richard Gain under a profit-sharing agreement. This one is really tough: according to Richard it is currently the most difficult cube in his collection. Well, I like a challenge!

There are six pieces, and it takes 30 moves to completely assemble it. I started out just playing around with it, trying to figure out where the different pieces go. Much like Primary Gain, since the pieces are very irregularly shaped it wasn't too hard to figure out where they went. This step took me about 15-20 minutes. The hard part is figuring out how to get them together since it takes so many moves.

I found that it wasn't too difficult to get all but one piece into place, so I did that and then imagined how the last piece would interact with the other pieces if it was present. I restricted myself to only moves that would be valid if the final piece was present. This helped me get a better understanding of how the pieces interacted.

Next, I removed a different piece and follow the same procedure. Eventually, this enabled me to discover which piece is the last to be added to the cube (and how to add it), which is usually the hardest step in this type of puzzle. Whew, what a sense of accomplishment! I think it took me over an hour, so I was quite elated when I finally solved it.

Not content to leave well enough alone, I disassembled it and assembled it a few more times to really get a good idea of how it worked. This is definitely a very cool puzzle and totally worth it for the money, only $16! Check one out if you think you can handle a high-level interlocking puzzle.

Overall, I was quite surprised by how playable these puzzles were given their size. That said, I have fairly sharp eyes and dexterous fingers, so your enjoyment of them may vary. I like the way these cubes look like something out of a science fiction movie. It seems like they should be capable of powering my time machine or something.

The fifth puzzle Brett gave me was called Triadenspass by Logika. The idea is to fit the three pieces into the hexagonal base. This looks fairly easy at first, but it is actually fairly challenging due to the irregular edges of the pieces and the base.

Each piece can be rotated and flipped for a total of four orientations. It can fit in any of these four orientations into any of the six corners of the hexagon for a total of 24 possible location/orientation combinations for the first piece.

It is easy to just try all of these combinations, but a bit tricky to keep track of which you have tried since the pieces have no identifying marks. Also, more than one of the 24 location/orientation combinations works, so you then have to see if you can get the next piece in (which can fit 8 ways).

I'm not sure how most people approach this type of puzzle, but that's how I usually do it: brute force! Still, it was a fun little puzzle to solve. I think it took me about 10-15 minutes.

This puzzle is flat and has a cover, which is nice, so it is good to take with you on the go. Also, Logika makes their puzzles out of recycled plastics, which is a good thing.

The last puzzle that I tried was Caramel Cube Puzzle by Hanayama. While it might appear that the challenge is just to fit the caramel-colored blocks in the clear box, the actual objective is to pack them into the box such that when you shake the box, the pieces do not slide around. What is even more interesting is that you can accomplish this feat using all 15 blocks or only using 14, 13, or 12! I love puzzles with more than one challenge, since it keeps me busy puzzling for longer.

This puzzle was designed by William Strijbos of The Netherlands and won second place in the 1994 Hikimi Puzzle Competition under the name Anti-Slide (the photo on this page is a spoiler for one of  the 14 block solutions).

I was able to find the 15 and 14 block solutions without too much trouble: there are a number of different solutions that work. However the 13 and 12 block solutions have eluded me for the several days that I have been working on it. There is only one solution to the 13 block puzzle so that one will be particularly tricky to find. I'm going to keep working on this one! [Update: I found a 12 block solution! Woo hoo!]

You may be wondering about Nemesis Factor, which I mentioned that Brett loaned to me, but I'm still working on that one and will post it in its own entry.

Once again, a big thanks to Brett Kuehner for all the nifty puzzles. I had a great time working on them!

If any of you out in internet-land feel like loaning me a puzzle that you would like me to review, I'd be happy to do so. Just contact me! I still have some in my queue, but I'll be running out in a little while, depending on how productive I am.

Next up, I'll be writing about a bunch of Bits and Pieces boxes that I got. I had much better luck than last time!