...Dinlas

There is a purity to interlocking puzzles. Just a few wooden blocks, glued together in the right way, can can produce confusion greater than the sum of its parts.  

Unlike more complex SDs, boxes & locks, there is no trickery, no fakery, no blind manipulations, no guess-what-the-designer-was-thinking, no I-can't-tell-if-that's-solved-or-not. There is no amiguity and there is nowhere to hide. 

There are, however, flippin' loads of them out there. It takes something very, very special to rise above the crowd but, when one does, they can be counted among my favourite puzzles. Daedalus, Kuchenstuck, Push Button, the best of the many, many TICs by Crowell, Sharma and more. They are all highly praised but, for some reason, Dinlas doesn't receive the same amount of reverence. 

Designed by Terry Smart (who, incidentally, lives just over the river from me, one of very few Scottish puzzlers that I've met), there are only 50 of these Cubicdissection builds out in the world (and I've never seen any 3D printed versions or suchlike) so maybe too few people have tried it.

The goal is to build a 4x4x4 cube inside a shifting 3-piece frame. 

Can an idiot solve Dinlas? 

Nope, nope, nopitty nope. Big fat nope. 

It didn't help that I assumed rotations were needed/allowed, just because it feels so much like a TIC and seems so very impossible without them, but they were no use anyway. Once I switched to only linear moves, I inserted each of the six pieces into the empty cage on their own and realised two things... 

1) this is still very impossible, and

B) this is unlike anything else I've ever solved. 

The only reason I know there is a solution is because Tom emailed it to me. I don't think I ever would've got it on my own, it is simultaneously quite simple and really difficult to find. It would require serious thought, planning and a big, working brain.