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!

Double Heart Arrow

If there is a prize for the cutest looking Exchange Puzzle at IPP34, Yoshiyuki Kotani's Double Heart Arrow would surely be a top contender.

Not only is it cute, it's also colourful and whimsical looking. The puzzle comes unsolved in four loose pieces and the object is to "pierce" the heart with the arrow. All the pieces are laser cut from acrylic and quality very good. The heart consists of two identical pieces, one in red and the other pink. The arrow is split into two halves, in transparent orange and yellow.

Effectively, the Double Heart Arrow puzzle is like a four-piece board burr and solving it requires you to navigate the heart pieces through the notches and channels along the arrow. The end point is marked by etched markings so you will know when the puzzle is completely solved.

Although it looks simple at first glance, it is in fact not that easy. I found myself close to the finish several times yet the final position of the pieces eluded me; one of the pieces would always be just one step out of place and I had to start all over again. This is a sequential movement puzzle with only one solution, it would seem. Get the sequence wrong, and you would have to back-track your steps.

Overall a nice interesting concept and a departure from the traditional wooden burr style interlocking puzzle, even though the design and solving process are similar. Not easy by any means but not difficult either. And Its fun looking and colourful appearance serves only to make you want to persist until you solve it.

Heart In Puzzle

Here's another Minoru Abe sliding puzzle I played with the last two evenings. It's the Heart In Puzzle with three challenges. The object of each of them is to move the "Heart" block to within the confines of the four identical L-shaped blocks.

Like all current Minoru Abe sliding puzzles available on the market today, the Heart In Puzzle puzzle is well made and packaging is in the form of a nice dark blue box. The instructions are in Japanese but the diagrams are self-explanatory. 

The tray is (likely) made of  pine, while the pieces are a different species of wood. Despite its high quality, Minoru Abe sliding puzzles are not expensive and prices range from about 2,100Y (US$17) to 3,700Y (US$31). They are available from online seller Torito (which unfortunately does not ship outside of Japan), CU-Japan and Amazon. The Heart In Puzzle cost about US$17/-, one of the cheapest.

Start Position No 1

Start Position No 2

Start Position No 3

Each of the three challenges is represented by three starting positions and the first requires a minimum of 28 moves. Not a lot moves compared to Minoru's other sliding puzzles (some of them in the hundreds) but I found this one rather difficult. It took me a rather good portion of an evening to solve the first challenge and the same for the second challenge. I didn't attempt the third. All the moves are linear. Initially I was wondering if the Japanese instructions (which I can't read) allowed for rotations, because if it did, it took me well less than 28 moves to solve. A quick check with sliding puzzle supremo Nick Baxter confirmed no rotations allowed so I had to take the more difficult route.

Solved Position For All 3 Challenges

For those into sliding block puzzles, the Heart In Puzzle is a must have and great value for money. Oh, and incidentally, the Heart In Puzzle does bear some similarities to Serhiy Grabarchuk's 22-move Sliding Stones.

Castle

"Castle" is one of two puzzles that came to me from the Pelikan Workshop. If you have not checked out their new revamped website, you should. They have now got a nice clean looking and user friendly interface with nice photos of their puzzles for sale.

This is my first puzzle from designer Tzy-Chung Chein, who has done over thirty-six designs to-date. My copy of the Castle is made from Dark Oak, Mahogany and Maple. Construction and quality is excellent and everything fits well and slides smoothly. The finishing details are also amazing; just look at the decorative inlays at the four corners! At 9cm x 9cm x 6.5cm, this is a large puzzle and easy to hold and play with.

But Pelikan has gone a step further and taken their creations up a notch above the other handful of well known puzzle makers; Pelikan now laser engraves their puzzles with the puzzle's name. For the Castle, its found on one of the pieces. A really nice touch.

The Castle consists of a box cage and four congruent pieces. It is not an easy interlocking puzzle to solve, at least not according to its relatively high level 18.16.5.6 solution. The pieces are normal regular burr pieces but the cage which holds them has 8 protrusions inside, one of the most I have come across. Despite this, I actually managed to take the Castle apart and put it back together without the aid of Burr Tools. Not the intended way unfortunately, but via a short cut as the design seems to allow for an (unintended) rotation of one of the pieces. 

As a result, I got the first piece out in just under 10 moves! But still not easy by any means as the rest needed multiple moves especially the third and last piece which took me a while to figure out. Later on I configured Burr Tools for the Castle and indeed, as I discovered, the 34 moves for the first and second pieces are very tough; which I doubt I could have figured out on my own. 

The Castle is one of about half a dozen new puzzles recently offered by Pelikan, now available on their site. I am sure there will be more new designs which will follow soon. At 35 Euros, the Castle is also great value for money given the craftsmanship that comes with it.

Cast Keyhole

The Cast Keyhole is the latest Cast Puzzle from Hanayama and came to the market in 2015. It was designed by award winning puzzle designer Vesa Timonen, who has designed a number of well known Cast Puzzles available on the market today including the wearable Loop, Cylinder, Square and Donuts.

This puzzle came as a gift to me from another well known puzzle designer Goh Pit Khiam (thanks very much Pit Khiam!). The Keyhole is available from various online retailers including Amazon and Torito, however the latter doesn't ship internationally.

The Keyhole consist of two similar looking "maze" plates, resembling the jagged edges like the teeth of a key, which are interlocked together in the starting position. Object is to separate the two plates, via one of the openings on one of the plates. The Keyhole can perhaps be considered a much more difficult cousin of the Cast Key. Quality and finish is good and the Keyhole has a shinny finish. Usually I don't quite like polished surfaces, but for this puzzle, it looks fine. 

Its not a very difficult puzzle by any means and Hanayama rates it 4 out of 6 stars in terms of difficulty (ie fairly hard). But the Keyhole is not as straight forward as it may appear to be at first. In fact, Hanayama states on its site (translated from Japanese) that the Keyhole is a "3-dimensional" maze. Not sure tho' if "3-dimensional" is stretching it a bit here. 

As you play with the puzzle, you will discover that you need to shift the orientation of the pieces relative to each other to move the pieces towards the opening. But as you progress, some of the positions may result in a dead end. However with some persistence, eventually the plates will come apart. I was fiddling with the puzzle for several minutes trying this and that, and suddenly, one plate just came out and it was solved.  

A nice addition to the very extensive Cast collection. And as with the Cast puzzle series, value for money.

Black Hole Burr

I like the Black Hole Burr ("BHB") because its one of the few interlocking burrs that I can actually solve without Burr Tools or other aids. Plus the fact it has only 3 board pieces and a black "block". Not as intimidating as one might imagine.

The BHB was Rosemary Howbrigg's IPP34 Exchange Puzzle. It was designed by Junichi Yananose and produced by Brian Young of the new revamped Mr Puzzle. The three board pieces are made of laser cut acrylic and the block is wood painted black. Quality of construction fit and finish is excellent and everything fits and slides nicely.

At first glance, it doesn't look too difficult, after all, its only three pieces. But believe me, its more difficult than it looks. Its not too hard to get the three acrylic pieces together without the block and that is what I tried to do first, so as to get a feel of the orientation of the pieces and how they interact with each other and how the block might fit into the centre. Once I had figured this out, I then sorted out the fit of the block.

Having solved the BHB, while its not as difficult as I had expected, its no walk in the park either, at least not for me. And take a hint here; Burr Tools won't work for this puzzle (So you probably know what's involved).

Its a tricky puzzle made more challenging by the fact that the pieces are transparent acrylic, making it harder to see the outlines of the pieces and where they join/intersect etc. My less than perfect eyesight, especially at night doesn't help either.

Overall a well made burr puzzle that provides a nice challenge that does not overly frustrate; the type that one would classify as having "just the right amount of difficulty for an exchange puzzle".

Available from Mr Puzzle for AU$30/-. 

LL Puzzle

I got this beautiful 8 piece packing puzzle from the good folks at Torito during the IPP33 Puzzle Party in Japan two years ago.

The packaging is mainly in Japanese so I can't tell what the name of the puzzle is nor its designer. However a couple of puzzlers have since informed me after seeing this post that it is the LL Puzzle designed by Nob Yoshigahara.

This is a very nicely made puzzle. Again, not sure what the type of woods were used. [Edit: The wood for the box is very likely Cupressaceae, which is the type of wood used for traditional sake cups; thanks to Satomi Beattie for this information]. But the puzzle emanates a very nice fragrant and pleasantly pungent woody smell. The finishing is very good. The puzzle costs 1,944Y, slightly over US$16/-, inexpensive for such high quality. Unfortunately Torito does not ship internationally, so you will need someone who lives in Japan to get it for you. If not, UK based CU-Japan may be able to get the puzzle for you.

Object is to unpack and repack the 8 pieces into the box frame. While it is probably not that difficult to design a 3D packing puzzle using pieces of all different shapes and sizes, I think its a real challenge to design the pieces all to have a certain theme, certain number of units, congruent shapes etc. In this case, each of the pieces consists of two different coloured "L" shaped pieces joined together with each "L" consisting of 3 units. Each of the 8 pieces are 3D hexaminoes (ie 6 units) with different orientations.

To unpack is pretty simple. But to repack after scrambling the pieces is very tough. The bi-coloured pieces add to the confusion as well, since there is no symmetry to the external colours of the puzzle in the solved state. Normally in situations like these, I photo-document the moves just in case I get stuck. Burr Tools of course would also help. With the aid of my photos, I managed to get everything back into the box after trying for quite a long time without them.

If you are into packing puzzles, this is a neat one to own and superb value for money. And the nice smell comes free with it!

Coin Puzzles by MINE

I got these puzzles recently from Japanese puzzle designer, Mineyuki Oyematsu, or MINE as he known in the puzzling community. MINE runs a website where he sells a range of mechanical puzzles. The site is all in Japanese and the Coin puzzles don't appear to be listed on the site. But you can contact MINE directly via his international mail order link which is in English. 

Each of the puzzles have got rather cute names such as "Hard-Boiled Coin", Hole Vacancy Coin and "Remove A! Coin (^^)". There is also a fourth heart-shaped version called "Lucky Sixpence" which I now regret not getting. 

The object of each of the coin puzzles is, yes.... to remove the coin. All three puzzles are made of precision laser cut acrylic and the puzzles are made by layers stacked and screwed together. Quality of manufacture is excellent with nicely etched wordings.

In terms of difficulty, Hard-Boiled and Hole Vacancy are not difficult and I solved both quite quickly. Notwithstanding, both puzzles are rather tricky and may throw some puzzlers off for a bit because their mechanisms are well hidden.  

However I had some trouble with Remove A! Coin. Took me quite a while to figure out the mechanism and even then, after a few tries, I am still not exactly sure how the puzzle works. Of the three, this last one is the most tricky and difficult. I checked with MINE and he confirmed indeed the puzzle had a few tricks not found in the previous two. 

Very nicely made and pocket-able puzzles worth getting, and value for money too; their prices ranging from 1,700Y (US$14) to 2,100Y (US$16).

Lion Claw

This weekend was filled with family and other commitments so I decided that my puzzle for a Sunday evening should be something I can solve easily (and without Burr Tools). 

My choice was Yavuz Demirhan's Lion Claw, a relatively easy but great looking Level 5.2.2 interlocking burr. My copy was made from Canarywood by Brian Menold and it came courtesy of Brian when I ordered from him Jos Bergmans' Garmbaad. The pieces of this particular copy were apparently a tad too "loose" and hence did not pass the QC for sale on his website. But for Singapore weather, it was just fine; the high humidity made the puzzle pleasantly snug fitting but smooth sliding!

This is a relatively large puzzle and felt great in the hands. The object is to disassemble the 4 pieces. Not difficult (excellent for a non-burrist like me) and I got them apart in a jiffy. Putting it together required a bit of experimentation, but it was back to the solved state quite quickly, and I managed without any aids. 

Lion Claw with all 4 of its pieces congruent is a great novice's or beginner's burr (the sort of burr that I like). Also built thick and tough like a tank, so no fear of abuse.