Another Burr That Is Not A Burr?

This is an interesting 3-piece "Burr" called "New Tam's Burr R-End", designed and crafted by Hidekuni Tamura. It was also his IPP36 Exchange Puzzle.

The concept design for this puzzle is similar to the Murbiter's Pseudo Burr. Like the Pseudo Burr, New Tam's Burr looks like an ordinary 6-piece burr from the outside. This one is made of a heavy exotic hardwood (I am not sure what it is) and consist of various blocks glue together. Construction is very good with the puzzle coming in its own box and instructions. One thing I am not sure of is what is the meaning of the name and the "R-End" bit??

The object is to dis-assemble and then re-assemble the 3 pieces which when taken apart, look uncannily similar to each other. And because of this, once you take it apart and scramble the pieces, you may have some difficulty putting the pieces back to the original state, particularly if you get their orientations wrong. A rather clever design as the designer has not only managed up the challenge quotient with similar looking pieces but also by the way the pieces connect to each other without leaving an voids in the centre of the puzzle.

Is it difficult to take apart? No, once you figure out which one of the pieces needs to be the first to move. What about re-assembly? Yes, harder obviously; but because there are only 3 pieces, its not difficult as such with some persistence. There are only so many ways available for randomly trying to connect all three together (and the signature on one of the pieces also helps).

Theta & Triple Tango

What does a puzzle blogger do when he hasn't had time (due to work and other commitments) to play with new puzzles to write about them? Well, easy...he blogs about his own designs that have been produced by well-known puzzle craftsmen...nothing to solve and fret over!

And here are two puzzles I am shamelessly featuring, which have been beautifully crafted by Eric Fuller. There is one more coming from Eric's stable (in the coming weeks I think) but I will let that one be released first before shamelessly blogging about it!

The first is my Theta (the exact name is 9 Theta) since it has 9 burr pieces plus a cage. Excellently constructed of Maple and Purpleheart, this one has a level 15.3.3.1.2.1.2 solution requiring a total of 29 steps to completely disassemble. Great attention to detail here and yes, I still need Burr Tools to help me re-assemble after taking it apart. 

Currently all 48 limited edition copies are sold out. Personally for me it was a nice design exercise and really a "no big deal" kind of interlocking burr. My burr design capabilities are pretty limited and I was surprise Eric chose Theta to produce for his site. But the few comments I have received from purchasers of this puzzle has generally been good. 

My second design is a sliding block puzzle called Triple Tango. I was able to design Triple Tango thanks to Goh Pit Khiam who shared with me his sliding block design program which he authored a while back (a software that works similar to Burr Tools, where you can specify the shape and units of the pieces etc). 

There is also a freeware programme called the SBP Solver by Pierre-Francois Culand but this program is rather limited in that the shapes for the pieces can only be either squares or rectangles. But for anyone who has never designed a sliding block puzzle, the SBP Solver is good enough to get you going for a start.

To see the many incredible sliding block puzzle designs out there including those by Minoru Abe, Serhiy Grabarchuk, Ed Pegg, Nob Yoshigahara just to name a few, check out Nick Baxter's Sliding Block Puzzle Page.

Start Position

 The version made by Eric consists of 6 pieces and the goal is to exchange the light and dark blocks found at the top and bottom. Eric had even made an acrylic cover with the starting position of all the blocks etched onto the surface. The puzzle is made of maple, mahogany and walnut.

End Position

This puzzle can be configured for various levels of difficulty. 78 moves (5 pieces only, move a single 2x1 block from the bottom slot to the top slot). 104 moves (the version shown here) and 122 moves, by adding another 2x1 block to be surrounded by the 4 larger blocks. And why is it called Triple Tango? Because the centre pieces "dance" three times round the inside of the tray (clockwise and anti-clockwise) during play before both the dark and light coloured 2x1 blocks exchange positions. Triple Tango was also the inspiration for my Tango 72 IPP36 Exchange Puzzle in Japan this year.

Again this was a surprise for me as I didn't think Eric would produce a sliding block puzzle like that where the pieces are uncovered. Anyway 46 copies of the Triple Tango were made and they are all also sold out!

Seal

This weekend, I played (or rather re-played) a puzzle that has seen a number of incarnations over the years. The puzzle is Naoaki Takashima's IPP36 Exchange Puzzle called Seal - Slide-Blocked Sliding Block Puzzle. 

Start Position

End Position

The original version of the SBSB with a garage and car theme was designed by Bill Cutler in 1987. Bill made a later version using the "seal and ball" theme and entered it in the 1988 Hikimi Wooden Puzzle Design Competition where he won the Grand Prize. Subsequently Tom Lensch also made versions of the original SBSB and his latest version is featured in one of my previous post, suing a "twin arrows" theme. 

Naoaki Takashima is a Japanese Puzzle collector who reputedly has the largest private collection of mechanical puzzles outside the USA/Europe and in Japan. His version of the SBSB for the Exchange is different from the original Bill Cutler and Tom Lensch versions in several respects:-

1. The design is an "upside down" version of the original.

2. The pieces are made of laser cut double layer glued acrylic and removable from the tray. You can't see it from the photos but there is a groove running along the inside bottom edge of the tray with two of the pieces having "notches". The Tom Lensch version is interlocking and pieces can't be removed. This feature is a God-send and very necessary if you are stuck halfway and want to reset it to the start position. Tom's version is not so easy.

3. Handy size of 11cm x 9cm for ease of carrying around.

SBSB made by Tom Lensch.
The pieces are un-removable, except for the holding piece

Like the previous versions, the Seal takes a minimum of 41 rectilinear moves to solve. The main notable feature is that the piece with the red ball restricts the movements of the other pieces depending on where the piece is at the moment, which have been described in my review of Tom Lensch's version of the SBSB. 

Although I have played with the SBSB nearly two years ago, it still took me a while to figure out the moves again with the Seal and several times I had to re-arrange the pieces and start from beginning. 

Perhaps the best part about this puzzle is that all the action (min. 41 moves or more) takes place within a simple looking 3 x 2 size grid, and involving five rectangular pieces only, moving one at a time left right up and down...incredible design feat here!

As far as I know, all the other versions of the SBSB are not currently available but perhaps Naoaki, like most puzzle exchangers, may have some copies still left over from IPP36 for sale. 

2016 8 August

There are packing puzzles and there are packing puzzles. And 2D packing puzzles come in all shapes and styles. Aside from the typical standard "fit X number of pieces" into the tray version, there are those which require the puzzler to find a symmetrical shape, an anti-slide formation or in the case of the "2016 8 August" puzzle here, leave a certain designated portion of the tray uncovered.

 "8 August" is not just a packing puzzle, but it also bears a theme...it is a calendar packing puzzle, but more on that later...

This puzzle is Rikishi (Lixy) Ramada's IPP36 Exchange Puzzle. It is made from precision laser cut acrylic for both the tray and pieces and fits nicely into a standard CD case as part of the packaging. The details, text, numerals etc and instructions are beautifully etched onto the top and inside surfaces of the tray. A very high quality piece indeed.

The object of the puzzle is to cover up the tray with all the 6 given pieces but leaving a single date open. Since there are 31 days in August, there are 31 challenges here. What is interesting is also that each of the 6 pieces is a pentomino (ie shape made up of 5 square units) selected from the total of 12 possible flat pentomino configurations.  

The design and shape of the tray provides 155 ways to pack the 6 pieces into the box, but for each date to be left uncovered, this will vary from date to date. The easiest challenge is the date 26th August, which has 22 solutions while 7 dates in the calendar have a unique solution. And of course the rest of the dates in between have varying number of solutions (see photo). Quite amazing how Lixy managed to find a combination of 6 pentomino pieces which can reveal any one of the 31 dates in the tray! Lixy had probably also chosen the month of August for his puzzle to coincide with IPP36 which officially ran from 5th to 7th August 2016.  

I tried 26th August and it was pretty easy (given there are 22 possibilities) and next I tried my own birthday (9th August). 9th August has 5 solutions and this took me a bit longer to find. When it came to the dates with only 1 solution, well, you can guess....

8 August is not only interesting and fun as a packing puzzle (with not too many pieces), but there are varying levels of challenges inherently built in which can test the novice and the expert alike and anyone else in between. And If you ignore the year and the days and just focused on the dates, this puzzle can actually be turned into a perpetual calendar.