Cross Bones

This little black puzzle is Englishman Frank Potts' Exchange Puzzle at IPP34 in London last year. 

Can you spot the skull?

And unless I am way off tangent here or doing something wrong, the Cross Bones is one of the very few burr puzzles that I actually found easy to solve!

Physically Cross Bones looks similar to Frank's Level 24 Burr Bones sold a while back by Eric Fuller. Unlike its wooden cousin which comprises three pieces, the Exchange version is only two, interlocked together. And a lot easier! Frank has done a number of designs in the past, favouring in particular, three-piece burrs.

Cross Bones is 3D printed in ABS resin by Scott Elliot and the puzzle is rather diminutive, measuring about 4.5 cm across. Fit and quality is good. The two pieces are able to "lock" nicely without any free play. There is even a motif of a skull printed on one of the ends for added effect!

This puzzle is a level 6.1 puzzle and because its only two pieces, its a pretty easy solve. The moves are sequential with only one solution. The blackness of the puzzle also makes it a bit tricky to see the openings where the pieces can untangle themselves.

Easily pocket-able, the Cross Bones is a nice little puzzle good for passing to non-puzzling friends, who perhaps may require more than a little effort to solve it. Oh, and I forgot to mention, no burr tools needed here!