Saturday 29 September 2012

The Perplexing Palace Puzzle

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

The Perplexing Palace Puzzle ("PPP") was James Dalgety's competition entry for the IPP32 Puzzle Design Competition held during August in Washington, USA this year. Designed by James Dalgety, Martin & Brian Scoefield, it is what I would consider a semi-dexterity puzzle.


Measuring about 17cm x 9.8cm x 0.75cm, the puzzle is made out of acrylic. Construction fit and finish is very good. Physically, the puzzle is a flat tray containing within it 10 acrylic discs; 4 red, 3 purple, 2 black and the last one, which is smaller than the rest, a black disc representing the Queen. Covering the tray is a white cover with holes cut into it, large enough to see the discs inside (and put your finger in) but not enough to allow the discs to be removed or fall out should the puzzle be turned upside down

The object of the puzzle:-
"The Queen, surrounded by her nine attendants, starts in the centre of the palace. Take her out of the palace then return her and her attendants to their starting positions"



The discs inside the tray are packed loosely and you can slide the discs around by shaking the puzzle or you can use your fingers through the holes in the cover. The goal of course is to try to manoeuvre the Queen from her centre hole position to either the top left or bottom right holes where she can then be extracted.

Somewhat like the classic "15" puzzle, one starts by shifting the discs around to make way for the queen. This is exactly how I started but repeatedly, I found myself getting stuck at one side or the other, near the exit holes. Clearly it is not so simple; the coloured discs get in the way of the Queen and she is also hindered by other obstacles. Initially it appears there is there no way to get the Queen out. When you start playing with the PPP, you will know what I mean.

It took me a good part of the evening but eventually I managed to get the Queen to exit from the top left hole. To complete the puzzle, the Queen and her attendants (the rest of the discs) must be returned "to their starting positions". Here I also fumbled a bit before everything was finally back in place. Throughout, a fair amount of dexterity and nimble figures are required. The solution is pretty tricky but quite clever. Here's a tip; play with the PPP under bright white light or during the day if possible....warm or cozy lighting will wreck havoc with the colours of the discs.

Overall, an interesting and challenging puzzle that I think, falls outside the usual genres. True to its name, the PPP is rather "perplexing" indeed, at least for me. Nice and unusual design and worth acquiring. Contact James Dalgety directly via his site http://puzzlemuseum.com if you want to purchase one.

Friday 21 September 2012

Pack-Man

This very colourful tray packing puzzle comes courtesy of Chris Enright, who entered it as an entrant for the IPP32 Nob Yoshigahara Puzzle Design Competition held in Washington just this August. This is Chris' second competition entry, his first being the Polarity Puzzle in 2009 at IPP29.


If you did not already know (especially readers who are of the Gen X and Gen Y age group), "Pack-Man" is a play on the word Pac-Man, a computer game that came out in 1980 and one of the most famous (and iconic) arcade games of all time.

True to its namesake, the Pack-Man puzzle consist of four similar looking odd-shaped pieces (the "enemies") and the fifth piece, Pac-Man which looks like a circle with a quarter portion cut away.  Chris has even kept to the original colours of the arcade game; the four similar looking pieces are red, pink, blue and orange and Pac-Man yellow. For a history lesson on the Pac-Man game which started the video gaming revolution, click here.

This tray packing puzzle measures about 11cm x 9cm. All five pieces are made of laser cut acrylic and the tray ABS plastic. Quality and finish of the puzzle is very good and the tray is even slightly textured for better grip.

The object of course is to fit all five pieces flat and flush within the tray. While all the pieces may look cute and colourful and the puzzle seemingly simple looking, don't let this fool you for one moment. It is actually harder than one might think....very hard in fact...at least for me, especially since I don't have much experience with tray packing puzzles.

I spent two evenings trying all sorts of configurations to fit the pieces into the tray but with little success. Always the fifth piece would jut out of the tray so slightly! The way the pieces are shaped and the curved corners of the tray kept throwing me off tangent over and over again...I was just not seeing it right. Finally, I gave in and emailed Chris for some clues. I felt some consolation when Chris replied that a very experienced puzzler had also emailed him for help. I wonder who might this person be?

Even with the help of his clues, I only managed to finally solve it after another hour or so. A lot of effort was put in to design and shape the pieces the way they are so that there is only one solution. Compared to packing pieces that are straight-edged, irregular shaped pieces I think are much harder to figure out.

A nice, well-made and very challenging puzzle indeed. The Pack-Man is available from Chris directly via his email.

Sunday 16 September 2012

IPP32 Exchange Puzzle From Wil Strijbos

Update 26 October 2017 - Dear Reader, please check out my new puzzle blog and e-store at http://mechanical-puzzles.com

Wil Strijbos calls his Exchange Puzzle at IPP32 the "Exchange Washington DC". A bit of a mouthful here so I will just term it "The Exchange".


Wil's Exchange can be classified as an "Impossible Object". One look at the puzzle and you can see why. The Exchange is made up of a 60 ml urine sample container, within which there is a lock with key inserted, both suspended at the end of a red plastic rod that runs through the container's cap. Residing at the bottom of the container is a steel ball bearing. The bottom of the container has a cut-out hole, but not large enough for the ball bearing to pass through.

At the top end of the red rod is a screwed-in loop which hangs another key and a rectangular-shaped ring. A rubber bung helps to hold the rod in place and prevents any unnecessary sliding down. The cap has an unbroken seal so you probably wonder how Wil had managed to squeeze the lock and the other contents into the container.


The object of the Exchange is to remove the ball bearing and have the final puzzle looking exactly like the "Solution Picture" (see above photo). There is an additional challenge which is shown on the reverse of the photo below-to get the rectangular ring over the shackle of the lock inside the container.


Solving impossible objects requires logical thinking and a systematic approach. For this one, a fair amount of dexterity is also required. I discarded my usual trial and error method and actually spent some time analysing how to extract the ball bearing.

There are twelve steps to solving the puzzle as intended, at least according to my count. Without giving too much away, firstly there is no need to use force; the laws of physics cannot be defied. Secondly, do not attempt to break the seal and unscrew the cap (I don't think Wil intended it to be solved this way). Lastly, everything you need to solve the puzzle is there and no external tools are required. You just need to think creatively how to use what's been given (in a way, you can think of this like a sequential discovery type puzzle)....and if you happen to have nimble figures, this would certainly help as well.

This is my first impossible object from Wil (who has produced a number of Coke and other bottle creations in the past). I found the Exchange very enjoyable and while the removal of the ball bearing itself is not too difficult, it is the getting everything back into position that is more challenging. For a while I was caught off guard; the way forward for the last two steps was right in front of me...yet I just didn't see it.

What I like about the Exchange is that you can see everything that you are doing - no hidden this or that. Definitely worth getting  for both the fun factor and puzzling aspect. As of this post, I am still puzzling over the second challenge which seems to be a real tough cookie!

Friday 7 September 2012

Rebanded Dovetail

The Rebanded Dovetail was Robert Sandfield's and Kathleen Malcolmson's exchange puzzle at IPP32, held during August this year. I managed to get a copy from Wil Strijbos who had attended IPP32 and brought back with him extra copies of the Dovetail and some other puzzles.

This is my second Kathleen Malcolmson puzzle after Bowling Alley In A Briefcase which was reviewed some time back in this blog. The Dovetail is hand-crafted by Kathleen in her workshop. In fact she has recently started her own puzzle blog and her first post is about this Dovetail.

Constructed of light baltic birch plywood and contrasting with walnut and lacewood, the Dovetail spots four distinctive colour tones. In particular the lightly textured surface of the lacewood which forms the two bands surrounding the box gives the puzzle a rather classy and unusual appearance.



Dimensionally, the Dovetail measures 8cm x 6.2cm with an overall thickness of 3.7cm. The puzzle is very well made and fit and finish is excellent with all sharp edges smoothed out. All parts have been cut to very exact tolerances (see the dovetail joints) making everything feel solid and tight. Of course, all this quality came with a rather expensive price-tag.

The object of the Dovetail is to open the box and remove a one-dime coin within. The puzzle has been classified as a trick-opening/puzzle box. A number of steps are required to open the box and depending on how you count, there are six moves required to free the dime inside. While the Dovetail does not have as many moves needed as some of its more complicated Japanese style counterparts, the execution of the solution is quite unusual and rather clever.

The dime out of the box....smallest denomination around but don't underestimate this little guy! 
It didn't take me long to figure out the first step and the next two were pretty easy. The fourth step was also easy and thereafter, this was where I got stuck. Took me a good ten minutes or so, but eventually I discovered the fifth step and finally got the box to open. This step was rather tricky (probably the trickiest!) and quite unexpected. When I finally got to peek at the inside, I saw the amount of work that went into making the puzzle....hmm, maybe it isn't that expensive after all!

Overall, I found the Dovetail entertaining with a sufficiently nice amount of puzzle challenge. This is not to say that it is an easy solve...no, by no means at all. But definitely fun and most experienced puzzlers would be able to solve it without too much frustration.