Oskar van Deventer, yet another prolific puzzle inventor who contributes with many of his designs for the Hanayama Cast Series (11 so far), has outdone himself, again, with the Cast Nutcase, which may as well drive you nuts if you attempt to solve it. The Nutcase was released by Hanayama in November 2006 and the key word is "interlocking".

The puzzle itself is very different from any of the others in the Cast family. The design doesn't stand out much and its object is anything but straightforward, which might take some time to even begin to understand what you're supposed to do with it. Yes, the puzzle does comes with an explanation, but only tells you what you're supposed to accomplish with it, not a single clue as to how to get there. In fact, the Nutcase has two goals: the first is to remove a small nut that moves freely inside it; the second goal needs you to swap the engraved nuts "Nut" and "Case" over as to read Casenut instead of Nutcase. I believe both can be accomplished at the same time, but I can't confirm that, as I didn't solve it yet.

The Nutcase is one of the toughest Cast Puzzles I've encountered so far, right on par with the Vortex, and I own all of them. It's rated by Hanayama with the highest difficulty level 6/6, and in my opinion these two should have a special rating of their own, as an exclusive level 7.

I got the Nutcase back in April this year, together with a lot of other puzzles from Sloyd, and since then I've tried on and off to solve it. The result, as expected, is always the same. I end up getting frustrated and leave it for another few weeks to try again. After eight months of constant disappointment, I'm ready to admit defeat on this one. I just can't figure this one out. The outer nuts can be screwed on and off freely up and down the bolt, but there's no apparent visible change with the movements. The bolt is actually two bolts that should come apart, but the only thing you notice is a slight movement of less than a millimeter when you try to pull them apart. There's a small hole on both sides that allows you to see a small nut move inside, but again there's no clue of what its purpose is in the actual solution. I guess this one has to stay unsolved for quite a long time, until I gather enough courage to pick it up again.

Closing Comments:

If you really like those close to impossible challenges, the Cast Nutcase is the right choice for you. Whether you're a veteran puzzler or not, be prepared, as this puzzle might be the toughest nut to crack yet.

Availability: You can get the Cast Nutcase at Sloyd, in Finland. You can also find there all the others in the Cast Series.

Links:

Oskar van Deventer Official Website

Hanayama Cast (in English) - Very useful website in English, with plenty of information on all things Cast.

Hanayama's Factory Visit (Many thanks to Roxanne Wong for sharing these pictures)