Is Metagrobological Science Broken? - EnigmaTIC

Breaking News - Is Metagrobological Science Broken?  Recent events have questioned the very foundation of the Metragrobology community, leaving many puzzled.  An EnigmaTIC challenge is perplexing the experts.  Assessing the complexity of this conundrum is the conundrum.

Way back, a long, long, time ago, when I was a wee tad, my granddaddy put me on his knee and said “Son” (I don’t know why, but for some reason granddaddies always say son to their grandsons.  I guess it’s one of those economy of expression things even though my granddaddy wasn’t a C programmer).  “Son”, he said, “There are many important things in life you need to know and some are more important than others.  However, the one thing that you mustn’t forget is that if a quantity of cubes forming a completely filled PxQxR rectangular parallelepiped is divided into sets comprised of cubes that form a single contiguous entity, there is a way to divide the sets into 2 non-empty groups such that one group can be separated from the other along a single Cartesian coordinate system vector, if and only if it is possible to separate the pieces from each other”.  I always knew that no matter what else was happening in the world, I would always be comforted by this knowledge.

Now imagine my shock, when a good friend and highly respected metagrobologist declared that “I've found a space filling (all 64 voxels) design that requires more than one move to free the first piece. In fact, it requires several moves.”  Wow! That just shatters the metagrobological foundation that underlies all my puzzle knowledge.  I've come up with ways to do it with non-cubic dissections but not a straight-forward 4x4x4 cubic dissection.

So how did this whole kerfuffle get started?  On several of my Turning Interlocking Cube (TIC) posts, I explained that if there were no voids within the puzzle, the first piece can be pulled out in one move.  Andrew Crowell, the TIC master, thought that this sounded a bit fishy and set out to demonstrate that a cubic dissection puzzle with no voids could be developed requiring multiple moves to free the first piece.

I was saying to myself, “No Way!”, even though this announcement was debuted as a comment on my post where I declared, in a rather PedanTIC manner, that I had learned my lesson and that the correct way to approach a puzzle is with an open mind (see The Correct Way to Solve a Puzzle - PedanTIC).  How could it possibly be done?  I finally decided that it had to use the 4th dimension.  I always have problems envisioning how things look with that 1 additional dimension.

When the pieces were released, I immediately created a set and solved it very quickly.  There are 6 pieces and I used maple to make them.  The puzzle is not difficult to assemble, but the required rotations make it interesting.  When I solved it, it reminded me of Stuart Coffin’s classic, Wookey Hole, although that puzzle is a 5x5x5 cube and has conspicuous voids in the final assembly.

In honor of the ensuing controversy, Andrew named the puzzle EnigmaTIC.  So where did things fall apart and what did Andrew create?  In a prior post, I explained how the complexity of a puzzle is sometimes defined by how many moves it takes to remove the pieces (Puzzle Complexity).  Both BurrTools and Puzzle Will Be Played (PWBP) provide this information for a solution. 

The problem was incubated in my lazy description of both puzzle complexity and how it relates to puzzles without voids.  I’m sure that I would be severely reprimanded by my granddaddy if he were still around to set me straight.  I still hide the rulers in the house.  What I should have said was that the complexity was a description of how many moves it takes to remove something from the puzzle, where that something could be a piece or a subset of pieces.  This is the convention used by both BurrTools and PWBP.  There are many instances of puzzles where more than 1 interlocking piece comes out in 1 move like Wookey Hole.  In fact, my very first interlocking puzzle, the Kimiki Cube (In The Beginning – The Kimiki Cube) has 2 pieces that come out together in one move.

My apologies for the carelessness that started this kerfuffle, but we did get a new cool TIC puzzle out of it, so I don’t feel so bad.  Have I mentioned that I didn’t think it is possible to create a really cool 5x5x5 cubic dissection with a minimum 10 pieces that takes at least 25 moves to remove the first piece, or set of pieces, and each piece requires a rotational move to extract.

Earth Day Celebrates 50 Years - Globe Ball

Thousands of casualties in the animal world resulted from the 1969 oil spill off the coast of Santa Barbara.  Earth day was established the following year on April 22nd to raise awareness for environmental reform.  Today marks the 50th anniversary of Earth day, which is now celebrated around the world.

In honor of the 50th anniversary, I searched for a puzzle that would have a global appeal.  The obvious choice was Hanayama’s Globe Ball puzzle.  Unlike most Hanayama puzzles, this one is plastic and twice the normal size.  However, similar to several of the Hanayama puzzles, this one was designed by Vesa Timonen. 

Vesa’s original design was called Tangerine and entered in the 2008 Nob Yoshigahara Puzzle Design Competition, where it won a First Prize award.  Like a tangerine, the internal pieces consisted of wedges that make a complete sphere and there are 4 of them.  The peel of the tangerine wraps around the wedges and is divided into 2 pieces, reminiscent of the outer skin of a baseball.  The skin covers all the segments except for a small hole where you can use the tips of your fingers to rotate the segments within the tangerine.  Once the segments are in the proper position, the tangerine can be opened to free the segments.  However, this is not as easy as it sounds since you can’t see through the peel to see if the pieces are in the correct position.  All you can see are the edges of the segments as they rotate past the access hole.  This requires you to look at the edges and then rotate them while mentally trying to track where they are after they leave the opening.  Of course, all this assumes that you have determined how the segments need to be oriented to open the tangerine.

The original version of Tangerine was 3D printed using orange for the peel pieces and white for the segments.  For the Hanayama version, an additional layer was added to the puzzle and renamed Globe Ball using the Earth as the new theme.  The molten core has 4 red segments surrounded by 2 blue oceanic pieces.  The 2 new outer shell pieces are a transparent light blue with opaque white regions depicting the continents.  Now instead of having a single outer shell, there are 2, and the inner shell needs to be manipulated into position with respect to the outer shell.  This has to be accomplished while still manipulating the internal core segments through the hole that is now in both shells.  Another nice feature is the addition of a 3rd outer shell piece that screws into the hole making the globe a complete sphere.

The packaging for Globe Ball deserves some recognition.  The box is a simple transparent box showcasing the puzzle and all the inserts.  Everything is very neatly packaged and the Ball is cradled between 2 clear plastic inserts.  The plastic insert on the bottom covers the official base to display the puzzle.  Another nice feature is that the box not only provides the puzzle designer’s name but has his photo as well.

After solving Globe Ball or the original Tangerine, you can see where the inspiration for Vesa’s newer puzzle, Cast UFO (Uns@lv*bl# F!&#ing O$j@ct - Cast UFO), came from.  You can almost hear him say, I want to do something similar but totally different.  And he did.

Globe Ball is difficult to come by and I’m glad I was able to acquire a copy.  It is not a very difficult puzzle but it is very clever and displays well.

The Proper Way to Solve a Puzzle - PedanTIC

There is a right way and a wrong way to solving a puzzle.  The right way requires that you have an open mind with the ability to explore all possible solution paths.  Of course, puzzle designers know that you’ll go the wrong way and they'll do everything in their power to make that the most attractive path to the point where you can no longer see the correct path.  This was the lesson that I learned during last month’s Andrew Crowell Rotations and Obstructions Series - Turning Interlocking Cubes (ACROSTIC) series challenge: BioTIC (Green Beer ‘ill Cure What Ails Ya - BioTIC).

I applied what I learned solving BioTIC to this month’s ACROSTIC challenge: PedanTIC.  It also turns out that PedanTIC shares a lot of similar characteristics with BioTIC.  Although the pieces and moves are different, they share many of the same qualities and the description for BioTIC can almost be copied for PedanTIC - except that I was not caught unaware this time!

What are the similarities?  Like BioTIC, the first 2 pieces of PedanTIC can be pulled from the assembled puzzle in 1 move.  The third piece, however, takes 2 moves instead of 1.  These 3 pieces are mostly space fillers that allow you to figure out where the remaining pieces go.  All the real fun is in placing the remaining pieces where they need to go.  And what fun it is!

PedanTIC consists of 5 pieces that have to be packed in a frame to form a solid 4x4x4 cube.  As I sat there in quarantine playing with PedanTIC, I started to daydream about those last 2 pieces. The spikey ball piece looks like the SARS-CoV-2 virus and once it’s in the main body of the frame, it moves around without seeming to have a way of being removed.  Another piece acts a receptor for the SARS-CoV-2, which I’ll refer to as ACE2, and as they dance around in the cage, the SARS-CoV-2 virus attaches itself to the ACE2 multiple times.  Of course, once PedanTIC is completely assembled, the SARS-CoV-2 virus is in contact with all the other pieces including the frame.  Yes, we all seem to be a bit preoccupied with the latest Coronavirus - Wash your hands!

After my experience with BioTIC, I was able to solve PedanTIC in fairly short order.  My advice to anyone doing these 2 puzzles it not to do them back-to-back (albeit a month apart) like I did.  Throw a PackTIC or 2 in between.

This is the fourth post of the monthly ACROSTIC series.  You can find the prior posts of the series here:

• January: Puzzling DNA - GeneTIC
• February: TIC, TIC, TIC - PackTIC II
• March: Green Beer ‘ill Cure What Ails Ya - BioTIC

Here Comes Peter Cottontail - Kimiki Bunny

I found the perfect puzzle to highlight the upcoming Easter weekend.  This was going to be the coolest puzzle post ever.  One heart-stopping description after another documenting the brilliant execution of the solution process culminating in a series of vivid photos capturing the essence of the final state of puzzle completeness and tranquility.  I was pre-basking in the glory of the deluge of comments that would be coming forth from puzzlers around the world astounded by my puzzle solving prowess.

Too bad I was unable to solve it.  Tranquility was out the window not to mention how far away from the final state of completeness I was.  With a dozen pieces continually mocking me, I realized that I would not be able to solve that puzzle in time for this post.  Maybe it will get done for next Easter or some other Easter in a year starting with 2.

It was at this point that I needed a significant confidence booster and pulled out my good buddy Peter Rabbit.  Peter spends most of his time in a cabinet as part of my original puzzle collection from the 70’s with several of his other Kimiki buddies.  Not only is Peter good looking but he’s musically inclined as well, being equipped with a bell that merrily jingles as he hops along.

Altogether, Peter is comprised of 10 pieces.  To assist in the assembly, there are multiple anatomical hints to help you get your bearings.  The astute puzzle will be able to leverage these hints.  For instance, the face is drawn across multiple pieces and you can use that to orient them when constructing Peter.  The puzzle is cleverly designed to split the 2 eye circles in half across pieces.  This is reminiscent of Jos Bergmans’ Sun puzzle where you have to mate the 2 halves of a circle but Kimiki Bunny takes it one step further and has 2 split circles that have to be reunited instead of one.  Some puzzlers may find this tricky and if you aren’t careful, you may end up with something like cyclops zombie bunny.

It’s always nice to successfully solve a 10-piece puzzle.  If you find that this puzzle has too many pieces for you to handle you could try something with fewer pieces like Mega Six by Bill Cutler, which has roughly half the number of pieces as Kimiki Bunny.

The First of April - Fool’s Cube

It’s the first of April, and we all know what that means.  It’s a time for tricks, pranks, and of course, PUZZLES!  Since this post falls exactly on that magnificent day, I decided to celebrate by creating a little puzzle.  The design criterion was simple.  No, coming up with the design criterion wasn’t simple, the criterion itself was to be simple.  I don’t know why it’s so complicated to describe a simple criterion.

Simple in this context was a 3x3x3 cubic dissection that would be within the capabilities of most wood tinkerers to make.  That provided 27 cubes to work with.  To make it even easier, I decided that it had to be interlocking.  Anyone familiar with 3x3x3 puzzles knows that you really can’t make a difficult interlocking puzzle in that format, even if you wanted to.  Although, I was tempted to add half-cubes and add rotations, I stuck with the design criterion and kept it simple.  However, it still has a nice Aha moment to be enjoyed.

In honor of this fabulous holiday, the puzzle was named Fool’s Cube.  Since I haven’t started working in the garage shop yet, I made the prototype from some Cherry and White Oak pieces left over from past projects.  I was 3 cubes short of being able to make it all in Cherry.  Since there are only 4 wooden pieces, I decided to drill a hole in each and put them on a keychain.  This way, I can easily carry the pieces together and hand them to someone to solve.  I didn’t have an appropriate keychain and the one that I made is too large.  I’ll need to shop around for a more suitable one and plan on getting one of those nylon coated stainless steel wire keychains.

Fools’ Cube has a difficulty of 1.2.1 and there are no rotations.  You could put it in BurrTools and it will not only provide the assembly but show you step-by-step how to put it together, but don’t waste your time doing that.  Just build one and solve it on your own.  It will take you a lot less time solving it than building it.  If you do make one to try, you should time yourself to determine how long it takes you to put it together.  Most of you will do it in a couple of minutes.  Let me know how you do.  It took my wife a minute and a half.

Supporting Social Distancing - Burr Lock “E”

As many of us find ourselves shut in and social distancing becomes de rigueur, I thought it would be appropriate to review a lock puzzle.  Of course, since I’m a burr guy, I chose a burr lock, Burr Lock “E” to be specific.

Burr Lock “E” was designed by Christoph Lohe and released by Cubicdissection in April, 2017.  It was made from Honduran Mahogany, Ash, and Bocote.   Where does the “E” come into play?  Well, apparently there were several versions that didn’t make the cut before “E”.  I’m guessing, somewhere around 4.

A lot of puzzles have a key piece that you need to discover.  This puzzle has a rather explicit, in your face, key piece.  The nice thing about this puzzle is that it really is the key that keeps this puzzle locked.  In addition to the key, there is a frame, a hasp, and 4 other burr pieces that get packed in the frame.

I know it looks like a lock but please don’t try to turn the key.  That would be bad.  If you do and you hear a click, that would be really, really bad and you’ll need some glue.  No rotations are required and you may want to provide that useful hint to puzzlers that you hand this to.  Not to help them out of course, but to ensure that you get back the same number of pieces that you started with.

Normally, when you take apart a puzzle, I recommend that you wait weeks, months, or even years before reassembling it to ensure that you don’t remember any of the critical moves required to solve it.  When you finally stare at the pieces and wonder what shape they make, you know you are ready to begin the reassembly journey.  Burr Lock “E” attempts to solve this dilemma by having 2 solutions: one with the key in a vertical orientation and the other with the key in a horizontal orientation.  This way you can take it apart every couple of years and put the key in the alternate orientation.  According to Burr Tools, the vertical orientation has a level 26.2.3.2.2 solution and the horizontal orientation has a level 26.3.3.2.2 solution.  However, the solution to the horizontal orientation has an obvious rotation (I mentioned earlier that rotations aren't required, but I never said they didn't exist) to remove the first piece halfway through the 26 moves.  In fact, if you aren't consciously keeping it in place, it may just fall out. 

Burr Lock “E” is well made and well designed.  It is a lot of fun to solve and the required movements are fun to discover, especially the interactions with the key.  If you are tackling this as a fresh assembly, the locations of the pieces can be deduced fairly quickly and I recommend going through that process.

With respect to the 2 solutions, I was a bit disappointed that they weren’t more different.  Once you take it apart, you may still want to wait a year or so before assembling it to re-experience the joy of discovery.  However, the difference that was there, I didn’t see coming.  It wasn’t difficult to discover, but I wasn’t expecting it.

This puzzle has been sitting out on the china cabinet for several years waiting for me to solve the alternate configuration. You know how it goes.  You buy a puzzle with multiple solutions, you solve one of them, you mentally check off that you solved it, and then you never quite get back to completing the others.  Even though Burr Lock “E” only has 2 configurations, it's taken me almost 3 years to revisit it and solve the other configuration.

I noticed when I took it apart again that the exposed parts of the pieces were a different shade than the parts that were inside the puzzle.  This was most notable on the key.  Did it fade from the exposure to light?  No, it got darker.  However, it’s really not a problem when the puzzle is on display since it’s usually assembled and you can’t see the tan lines.  If this is a problem for you, you should keep your puzzles in the dark, in which case you might as well keep them in a plastic bag to cut down on the humidity fluctuations as well.  For those of you with humidity-controlled puzzle cabinets with electronically tinted glass doors, continue as usual.

Inspiration from Grandchildren - Little Kenny and Wooden Puzzles

How would you like to take a journey through 20 different must-have classic puzzle designs by world-renowned puzzle designers?  Along the way, the secrets of how to make them yourself will be revealed.

Several years ago, my good friend and master craftsman, Brian Menold, informed me that he was writing the definitive book on how to make wooden puzzles and asked if I would like to contribute a design.  Even before I knew of the world-class puzzle designers that would be included, I readily agreed.  I later found out that the book included designs from Stewart Coffin, Jos Bergmans, Yavuz Demirhan, Stéphane Chomine, Primitivo Familiar Ramos, Tom Jolly, and of course Brian Menold.  The cognoscenti of puzzledom.  Fortunately, I didn’t have the pressure of knowing the other contributors beforehand.

Brian’s guidance to me was that the book, called Wooden Puzzles, was targeting entry level woodworkers and he was looking for a simple design.  I translated simple to mean a puzzle based on a cubic dissection with rectilinear moves and a fairly small form factor, i.e., no larger than a 4x4x4 cube.

At about the same time that Brian asked for my contribution, along came my first grandson, Kenny.  He is a continual source of puzzlement and wonder.  When my grandson was 4, I informed him on some random sunny afternoon that he would be starting school the following year.  He looked at me, and in no uncertain terms said, “My mom said I don’t have to go to school”.   Trying my best to realign his thinking, I told him that everyone had to go to school.  Unfazed, he peered over at me again and replied, “I don’t need to go to school.  My job is inspiration!”  Well, how do you argue with that?  Needless to say, this post is about the puzzle that was inspired by Little Kenny.

The initial version of Little Kenny that was included in Wooden Puzzles is comprised of 4 pieces in a 4x4x3 format.  Only rectilinear moves are required and the level of difficulty is 5.1.1.  I was very happy with this design and thought that it was an excellent fit for the book.  Since the book has been released, I’ve received feedback from a couple of woodworkers with Wooden Puzzles and they loved Little Kenny.

Brian did an amazing job writing Wooden Puzzles.  Not only is it informative, but it is crammed full of pictures of puzzles, tools, jigs, and various types of wood.  The book is comprised of 4 main sections.  The first section provides an overview of tools for puzzle making, selecting wood for puzzles, and jigs for making puzzles.  The second section is the majority of the book and describes in detail how to make the 20 puzzles covered.  By the time you get through all 20, you should have a good understanding of the woodworking basics required to make these types of puzzles.  The following section provides some recommendations for taking your puzzle making to the next level.  Alas, the last section shows the solution for solving each of the puzzles covered in the book, but I know that you won’t be tempted to look.

Although Brian indicated that his book was for beginning woodworkers, I believe that it is suitable for woodworkers at all levels.  There are great little nuggets of information for everyone.  I pulled out my copy of Wooden Puzzles as I was writing this post and as I was flipping through it, I realized that it was time to read it again in preparation for making this year’s puzzle prototypes.  The book may also be of interest to puzzle collectors interested in the process of creating the puzzles that they collect.  Just don’t read the solutions to the puzzles provided in the back of the book.

Shortly after providing the initial Little Kenny design to Brian, I decided to make a more difficult version for the upcoming IPP35.  I was able to split one of the blocks to require rotational moves in the solution, thus becoming the first puzzle in the half-cube series.  I brought my updated Little Kenny prototype to IPP35 and it was well received.  Just like my grandson, it’s small size with only 4 pieces makes it look fairly innocuous but it does have a little bite to it.  And no, the solution provided in Wooden Puzzles won’t help you with the updated version.

After IPP35, Little Kenny was produced by the world-class craftsman, Tom Lensch.  The pictures in this post are of Tom’s version made with Jatoba.  With the successful release at IPP35, I decided to enter it in the Nob Yoshigahara Puzzle Design Competition the following year at IPP36 where it received the award for …. nothing!  Oh well.  It was up against some pretty stiff competition like Chain Store (Yanked My Chain - Chain Store) and Bitten Biscuits (Food For Thought - Bitten Biscuits).

You should get a copy of Wooden Puzzles.  It is available on Amazon here.  Then you can make your own copy of the original Little Kenny design.  If you want a copy of the updated half-cube version of Little Kenny, they will be available soon from Brian Menold at Wood Wonders.