Cast Keyring and Cast Cuby

I picked up a few more Hanayama puzzles at Eureka this past weekend: Cast Cuby and Cast Keyring. I didn't notice this when I first purchased them, but they are both designed by Oskar van Deventer! I really enjoy his puzzles, so this was a happy discovery.

I tried Cast Keyring first on my ride home on the subway: I like to start with the easier of the two so I can accomplish something before getting stuck on a harder one. This one is a level 2 out of 6, so I didn't expect it to be too much of a challenge. Even the simplest Hanayamas can stump you for a bit, though.

This was a nicely made puzzle, it has a similar type of finish to Cast Dolce, which I enjoyed. The weight is fairly good and it has a nice appearance. On the puzzle is inscribed the words "Key Ring." The words are an ambigram: if you turn "Key" upside-down it reads "Ring" and vice versa. This was a nice little touch because it makes it a bit trickier to orient yourself on the puzzle. The ambigram was designed by Scott Kim.

One strategy I like to use with puzzles of this type is to keep one piece in a fixed orientation. This makes it easier to tell which moves I have already done. In this way, I can explore the set of moves much like a maze.

I had a fun time solving this one: there was one unexpected move that I could have taken quite a while to discover, but luckily I stumbled upon it early. I think it took me about 5 minutes to solve, but I think it could have easily taken longer if I had been less lucky.

When I first got this puzzle, it held together fairly well with friction, but now it tends to slide apart (not completely, the actual solution takes several moves). That's fine sitting on my coffee table but would be a bit annoying if I had it in my pocket. Also, one move requires a bit more force than I would have liked to see, but that's not a huge drawback. Overall, a solid puzzle that I think will be a fun one to give to puzzle novices to get them hooked!

After solving Cast Keyring, I moved on to Cast Cuby. This puzzle is essentially a maze: you have to navigate the wedge back and forth between the faces of the cube in order to get it out. There is a nub on one face of the wedge that must line up with a notch on the cube face in order for a move to be possible.

It has a nice movement that is quite unlike any other puzzle I have seen, as is frequently the case with a design by Oskar van Deventer. I don't know where he comes up with all this stuff! If you like this puzzle, you would also enjoy Cast O'Gear (I liked O'Gear a bit better, though both are good).

I played around with this one for a bit on the subway but didn't have much luck. I was trying to be quite systematic and tried to develop a mental map but I ended up going in circles. Once I got home, I just played around with it for a bit and solved it in a few minutes. I think it took me a total of 30 minutes or so (this is a level 3/6).

Robert Stegmann has a great description and solution of this puzzle here (scroll down a bit). He has a map of the solution, but it won't really do you any good just glancing at it. I thought about making a map, but it would have been harder to come up with a notation system and working out a map than it would have been to just solve the puzzle by fiddling, in my opinion.

Still, Rob's analysis points out some interesting design features that make this a well designed maze. Oskar provided the solver with ample opportunities to make a mistake and end up going into a loop or to forget which way you are going and end up going backwards.

George Bell wrote an interesting article on solving puzzles with maps that you can read on his website.

I was a bit unsatisfied with just fiddling with it to solve it, so while shopping with my girlfriend I tried to take a more systematic approach. Working backwards from the finish, I was able to find an easier to reach target state that would lead me to the finish once I was able to reach it. It was easy to get confused just visualizing the moves, but eventually I figured it out and that method ended up working fairly well.

This is definitely one that could have a fair amount of replay value. Once you forget the solution, it could take you a little while to figure it out again. Another great puzzle by Oskar!