Brace Yourself 6 piece burr
25 February 2021Edward Hordern IPP33 Puzzle Exchange – Narita, Japan August 2013. 209 made. Now sold out. Presented and Designed by Frans de Vreugd. Made by Mr…
19 directional moves to remove the first piece from an 18 piece burr!
In 1953 Willem L van der Poel, a leading Dutch computer scientist, set out to design a puzzle with as many interlocking pieces as possible and came up with an 18 piece burr that took 4 moves to get the second last piece in and 3 more for the last piece.
In 1997 Mr Puzzle changed the burr to create a puzzle with 5 moves to get the last piece in. In 1999 he came up with this version which takes 19 moves to get the first piece out! And it doesn’t finish there…. After you get the first piece out there is still 5 more moves to get the second piece out, you will then be able to easily remove the next two pieces, but watch out for the 5th. HINT… Beware when trying to remove the 5th piece – it will take you a further 9 moves – and remember no force or rotational moves are necessary to solve this puzzle.
Yes, it’s so difficult you now get the puzzle assembled.
This puzzle was designed by Brian (alias Mr Puzzle) without the use of a computer. It was however analysed using a computer program by Andreas Röver (see the end of this detail page) and he found and even more difficult assembly of the puzzle, being a level 14.10.3.2.5.11.10. That makes 65 moves for complete disassembly.
REMEMBER – As well as a presentation card we provide a separate sheet showing a clearly and professionally printed solution with both graphics and text is packaged with every puzzle. Will this puzzle prove to be your “coming of age” as a puzzler?
Packaged ASSEMBLED – Yes, we feel this puzzle is so difficult that even getting it apart will prove very difficult! Size 120mm x 120mm x 120mm (each piece 120mm x 30mm x 30mm)
Analysis completed by Andreas Röver using his BurrTools program. The latest version 0.2.0 can be downloaded from here.
Statistics:
– highest first level is 19. There are 2 such solutions which are very similar to one another. Both solutions take 46 moves to completely disassemble. – other high level solutions exist with primary level 16, level 14.10, …
– the most interesting solutions in my eyes are 2 solutions with level 14.10.3.2.5.11.10. That makes 65 moves for complete disassembly, which is more than required for Burrloon. Burrloon requires only 64 moves with its level 33.8.something solution.
– the analysis took 1214463 seconds, which is 14.06 days of continuous calculation time
– the analysis found 880338023 assemblies
– that is an average of 725 assemblies per second that needed to be analyzed
– 7621 of those are actually assemblable, that is less than 1/115000th of all assemblies (so if you found an assembly it is probably not assemblable)