Autobahnkreuz

Update 23 October 2017 - Dear Reader, please check out my new puzzle blog and e-store at http://mechanical-puzzles.com

Its been a while since I last played with a Yavuz Demirhan design. So Autobahnkreuz was the puzzle of the day. Yavuz, as most puzzlers would know, hails from Turkey and currently has one of the most number of designs (409 as of this post) uploaded to PuzzleWillBePlayed. To say he is a very prolific designer would really be an understatement!

I got the Autobahnkreuz (which by the way in German means "motorway interchange") from the Pelikan Workshop, the guys from the Czech Republic who have been regularly bringing to the market wooden puzzles of outstanding quality. And did I mention that they are also value for money too?

The Autobahnkruez is no exception and my copy is excellently made with nice tolerances. Snug enough for the pieces to hold them themselves together but smooth enough to slide. This is one puzzle you don't want to be too "loose fit".

The puzzle is what is known as a board burr, meaning all the pieces are flat 2D. There are 8 board pieces in total, all of which are congruent, ie all the same shape. I was inspired by Yavuz's design here, which led to my (very) amateur design efforts resulting in the CrossRoads, a smaller 8 piece board burr design. Without Yavuz's design prowess, I only managed to get an interlocking design (level 12) by using all different shaped pieces. None of the elegance of Yavuz's 8 congruent shapes.

Autobahnkreuz is a rather difficult puzzle, not just in terms of the dismantling; which I managed to do so after a fair bit of trial and error. But the re-assembly is tough, unless you have a solid memory and remember all the steps in reverse. 

You will notice that the 8 pieces comprise of 4 pairs of 4 different woods (arcasia, maple, wenge and paduak). Firstly to put together the pieces to the solved shape is difficult enough (level 9.5.3.4.2.2.2). But you also need to get all the pieces to form a symmetrical colour pattern. Not to mention you have to grapple with up to 8 pieces at the same time. Thankfully Burr Tools was on hand. Instead of configuring BT for 8 congruent pieces (resulting in one unique solution with one single colour puzzle), I specified BT to have 4 different pairs with 4 different colours. Hence, you will end up with 648 assemblies of which one solution will give you the right colour co-ordination. On my BT file, its solution #76.

Burr lovers will like this one. Very challenging! Well made, nice big and heavy with a great colour scheme!