Rhombic Maze Burr

Derek Bosch had a prototype Rhombic Maze Burr (RMB from here on, 'cos I'm lazy!) on his table at the IPP32 Puzzle Party. He was demonstrating it to anyone who was interested and letting them have a shot at it … and then he had a sign-up sheet for folks who might just be interested – I played around a bit and duly added my name to the list, and earlier this year, Derek got in touch to say he had a couple and asked if I was still interested … and a little while later it arrived. :-)

The RMB is Derek’s development of Kagen Sound’s (Schaefer’s in old money) Maze Burr. Kagen’s Maze Burr has maze plates spread around the faces of cube while Derek’s RMB has maze plates on the faces of a rhombic dodecahedron (the clue’s in the name!) … so there are double the number of maze plates to negotiate. The guts of the RMB and the maze and pin plates are all 3D printed and then treated with some Bosch magic-sauce to make them slide nicely. (I may have lied about the magic-sauce, but the pieces all move really nicely so I suspect he's done something to them!) A set of stainless steel screws keeps the plates in the right places and forces you to navigate the maze.

As with the Maze Burr, the RMB’s maze plates can be rearranged to change the depth of the solution required … and with twice as many plates, you can get some pretty high level configurations … my RMB arrived with a (mercifully low) solution of around 30-odd moves – and the booklet that Derek provides with the RMB includes 50 challenges ranging up to a 379 move monster set up … presumably for people he doesn’t like very much!

One of the maze plates is unique in that it has an exit off the plate, which, when the pins are in the right orientation, will allow that plate to slide out entirely – that is your goal. The exit plate is also the only plate that will be able to move at the start, albeit in the “wrong” direction. 

Moving the first plate exposes a gap for the adjacent pin-plate to slide out, which in turn allows the maze plate to slide… and so on… a couple of the maze plates have hook-shaped channels that allow you to move a panel and then immediately retract the pin plate you moved to allow that move … and sometimes that can be very useful – as it effectively allows you to fork down a different branch (if you’re thinking about your path as a tree structure). 

The RMB comes in two sizes – I went for the larger of the two and I reckon it’s a nice size to play with in the hand – it’s a nice handful. :-)

Once you’ve solved a particular challenge, a few minutes with a screwdriver and you’re good to go with another challenge – I’ve worked through a couple of the simpler ones so far and they don’t have that many dead-ends or forks in the road, so it’s not easy to get totally lost on them. 

Every now and then I’d find myself benefiting from trying to work back from the exit though… although sometimes, if you haven’t noticed a fork in the road, or find yourself down a blind alley, you just end up convincing yourself there is no solution… and several times I’ve ended up with an odd panel or two sticking out with no apparent way to get them back in again… 

I reckon it’s a great development on the theme and the extra panels provide a suitable step up in terms of complexity – and it’s fun to sit and fiddle with! Even the “simpler” challenges aren’t trivial … Nice one Derek!

Helical Burr

If you’ve been following this year’s puzzle news you must have spotted that Derek Bosch won the prestigious Jury Grand Prize at this year’s Nob Yoshigahara Puzzle Design Competition with his Helical Burr. 

I’d heard some rumours of something interesting in the works and then seen a late prototype at one of our puzzle gatherings and it drew quite a few admiring comments from those who had a play with it…I didn’t get to spend much time on it before it headed up to its new owner, but it’s cylindrical shapes definitely sets it apart in burr-world. 

A while later in Japan I had a bit of a play with the copy in the Design Competition, but as luck would have it, someone before me had left it in bits, so I had a half-hearted attempt at putting it back together again and failed miserably so I quickly moved along to something simpler in order to restore my sense of self-worth!

At the end of IPP, sitting with a bunch of Renegades there was a really loud cheer when Derek’s design was announced as the Grand Prize Winner at the awards dinner – one of “our guys” (not sure why they let me associate with them!) had won one of the big prizes, again! Cue all manner of celebrations that could only have been a little bigger had Derek actually been in the room at the time.

Back home a little while after IPP and Derek let us know that he was going to make up a few and was taking orders, so Gill decided to get me one for my birthday, and unbeknown to her at the time, I snuck in an order for one of Derek’s Rhombic Maze Burrs as well, but that’s a whole other blog entry…

When I received my copy I hadn’t really had much of a chance to play with one yet, so I was really starting from scratch as it were. The puzzle is 3D printed by Shapeways and dyed by Derek. It consists of 4 different coloured pieces that make up an inner core of two interlocking pieces and an outer frame. You can see from the outside that the frame will unscrew into two pieces, and your first temptation may well be to try and unscrew them… 

When I started playing with the burr, my first thought was that it was rather stiff and the pieces were very tight… so I kept at it and hoped that it would loosen up with a little playing, but I wasn’t getting much movement at all. I started paying more careful attention to the way that I was gripping the pieces to make sure that I wasn’t blocking my movements, and that helped a little, unscrewing the outer case a little, but then, nothing…

Realising that trying the same things over and over again weren’t yielding any more useful results (I’m sure there’s a quotation about that somewhere!) I switched tack and tried something else. And all of a sudden, I had movement of a different and rather unexpected type. Finding the next move didn’t take quite as long as the first, and from there on progress was a bit better, until, at around 11 moves the first piece is removed.

Separating the pieces helps you understand why the pieces behave the way they do, with strange-shaped protuberances inside the frame pieces to both obstruct the inner pieces and force them to turn in a particular direction… quite ingenious and how the heck Derek designed it, I have no idea! 

I find playing with it a lot of fun and have found myself going through the movements of opening and closing it stacks of times because it’s fun to fiddle with! There’s a lovely little bit of puzzle choreography at play as the four pieces interact in a series of movements that take it from a compact cylinder to an extended, open structure with all its innards on display – just before it releases the first piece and the rest come apart pretty simply. 

Definitely a puzzle with plenty of repeat playability – and it’s a pretty cheap form of therapy!

Great design Derek, and a worthy winner!  Well done mate!

Derek’s Half Dozen

Designed by my mate Derek Bosch, this was one of Eric Fuller’s latest round of offerings.

It is EVIL. 

I should stop right there – and I probably would if it wouldn’t make the blog post look rather picture heavy and text light… so I’ll ramble a bit. 

Assembled, it looks pretty benign – almost like a 6-piece board burr with fairly fat boards. However (there’s always a however, isn’t there?) as soon as you start moving any of the bits, it is very clear that this one is rather devilish: each of the ends of the pieces are perpendicular to one another … There was probably a clue to that in the starting shape – if it was a board burr, then the boards would have had to have been twisted through ninety degrees, on the inside. 

It takes a little while to get used to the movements and the fact that a horizontal plate on one side is connected to vertical plate on the other … I suppose at least they connect straight through, unlike some designs! 

Along the path to disassembly you’ll find some pieces come tantalisingly close to falling out, yet they remain thoroughly trapped until the 26th (!) move finally releases the first piece … oh  and don’t be surprised if you find yourself apparently going backwards and forwards a few times – you might still be on the right trail! 

I am not ashamed to say that reassembly without the use of my favourite puzzling software is (well!) beyond my puzzling powers … even Eric’s kind use of three different woods (Ash / Wenge / Bubinga) for the pairs of pieces is not enough of a hint to enable me to assemble it on my own. 

The pieces look pretty simple, if a little unusual, and yet they produce a wonderfully challenging puzzle. Eric’s done his usual terrific job of creating pieces that not only look great, but fit together marvellously and will stand the test of time (the sticks join the plates in a straight through joint for extra strength). 

A couple of us told Derek that his design was evil on the Cubic Dissection Facebook group - he took that as a compliment … and he should – it’s a great design, beautifully produced by Eric! Nice one guys!