Friday 25 December 2015

Lee Krasnow’s Barcode Burr

…there are some puzzles that money can’t buy – people don’t sell them once they get hold of them. 

If you’ve ever handled a copy of Lee Krasnow’s Barcode Burr you will recognise that statement immediately… finding one for sale is the hard part – handing over the (not-so-insignificant-sum-of) cash is the easy part! 

This thing is an exercise in precision engineering and art – all wrapped up in a glorious binary puzzle…

Designed and perfectly crafted by Lee back in 2004, the Barcode Burr is, at its heart, a dissection of a cube into six identical pieces… which is interesting in and of itself as it appears to be a 3*3*3 cube(!) – look a little closer and you’ll see some diagonal splits across some of the blocks – so the maths sort of works a bit better…

Each piece has some combination of pins and / or mazes on them, and each piece interacts with its neighbours’ pins and mazes… enforcing the following rules:

  • A piece may move if the piece immediately before it is extended and all other pieces before it have been pushed back in, and
  • A piece may be removed if extended and every piece before it is pushed back in and every piece after it has been removed.

Which gives us the classic binary puzzle formula…

The trick here is you can’t pull the pieces out:  you need to push them from the opposite side, which takes a little getting used to because the pieces expand outwards on the cube’s main diagonals… finding the first move can be a little tricky – one of those little triangles will eject a lump of wood in the opposite direction – find the right one and the first piece extends… orient the cube comfortably in your hands and start running through the sequence: 1 out, 2 out, 1 in, 3 out, 1 out, 2 in, 1 in, 4 out… and so on… until you reach move 64 where the first piece can be removed, with a very satisfying click! .... Huzzah!

Interestingly, Lee’s design notes point out that there’s a shortcut that allows the first piece to be removed just after the 32nd move… this happens because each of the pieces needs to interact with all of the other pieces to enforce the full binary sequence, but as the pieces pull out along the main diagonals of the cube, each pair of pieces shares a shifting axis and therefore cannot (other than trivially) interact with its opposite number…interesting, but why on earth would you want to take a short-cut on pure puzzling therapy?!

Those same design notes say that he’s made six other copies of the puzzle – and this one’s marked “No. 7” – so I suspect that there really aren’t that many of them out there in the wild! 

Barcode Burr took an Honourable Mention in the 2004 IPP Design Competition against some very stiff competition. 

It’s a seriously beautiful object made of Eastern Hard Maple with inset Macassar Ebony stripes – which is where the name comes from… definitely one of my awesome puzzle finds of the year!

[Blogging on Christmas Day?? Yip – turns out I’m allergic to Strictly Come Dancing and the Michael Buble Christmas Specials that the rest of the family love… so I get to do a little bloggin’ without the guilt of not working on that other project for one day… so Merry Christmas puzzle-people!!]

1 comment:

  1. I fainted,,,,only Stephen Miller has ever attempted making this incredible puzzle, a 3D printed plastic version which is affordable, and it took him 3 years. BTW a ball Barcode burr is not possible, I tried,,,heh heh