DaVinci's Secret

I had seen the Sacred Myths and Legends series of puzzles a number of times when searching the web for puzzles, but never got around to buying them. Even though they looked decent, $30 seemed like a lot, considering that I would probably want to buy all six.

One day when I was at Eureka Puzzles and Games shopping for a new mechanical puzzle, I noticed that they had almost the whole series for sale for 40% off! Not a bad deal, considering I was thinking of buying them anyways, so I ended up picking up the whole set, except for The Enigmatic Temple, which he did not have in stock.

I decided to attempt them in order, since each puzzle supposedly contains hints for a password that can be used on the website to unlock clues to the next puzzle. This sounded like an interesting challenge, so I started with DaVinci's Secret, the first puzzle in the series.

This is a fairly large puzzle: almost a foot in length and it looks quite nice with the contrasting tones of wood. It rests on a stand for display that is not part of the puzzle. Inside the box is a cryptic clue that is supposed to be of some help when solving the puzzle, but I didn't really find it much help at all. I'll post it here because it is in the box, so it isn't very secret, and I don't think you'll be able to make any sense of it:

Ancient Roman Architect's

proportions are essential for

symmetry and positions among 16.

Even knowing how to open the puzzle, I don't really see how this is supposed to be helpful. I can kind of back into what they were intending, but even that isn't all that helpful.

The puzzle itself is only moderately challenging, though I think most seasoned puzzlers would consider it fairly simple. I was able to open it in about 10 minutes. It works as you would expect it would, though I supposed I shouldn't say exactly how it works since that could spoil it for you. The five central plates rotate about the center axis, though one of mine was a bit sticky, which was somewhat annoying. The other plates turned fairly well.

I was a bit disappointed that it wasn't more challenging, but this was only the first in the series, and I was aware that some of them were easier than others. Now that I have completed the others, I know that this one is one of the easiest of the series.

Once I got the puzzle open, I had to figure out what the clue inside meant. I was completely dumbfounded by the clue, it didn't really make any sense to me what the answer could be. After working on it for a while, I finally gave up and looked for a hint online. After reading the hint, I didn't have the "oh, of course!" moment, I had a "how the hell was I supposed to know that?" moment.

Now, I'm not very good at this type of word puzzle to begin with, but I think it was exceedingly difficult. Of course, there are probably a number of people smart enough to have solved it, considering somebody needed to solve it in order to post the hints, but I'm certainly not one of them!

In addition to being hard get, the hint that you unlock if you enter the correct password on the website is anything but helpful: it is another cryptic clues that didn't help much on The Equation, the next puzzle in The Sacred Myths and Legends series.

I was hoping that the series just got off to a slow start and that some of the remaining puzzles would be more interesting. Tomorrow, I'll write about my experience with The Equation.

Tier Box

I had heard about Tier Box by Eric Fuller from Matt Dawson, who had seen it at the 2009 International Puzzle Party, and it sounded like an interesting box. I planned to purchase one, but since quite a number sold as preorders at IPP I was worried that I might not be able to get one before they sold out: only 34 were made. Also, CubicDissection.com is blocked at my office, so if it went up for sale while I was at work, I could have missed it.

I got the email announcing the new products at CubicDissection while I was driving to a swing dance on a Monday night, so as soon as I pulled into a parking space I hopped on my girlfriend's iPhone to order one. It took a little while since I had to update my address on PayPal (I had recently moved), but I got the order sent and went off to the dance.

A few days later, Tier Box arrived in the mail and I couldn't wait to give it a try. I sat down in my recliner and admired its nice finish and details. The seams were very well done and I also liked his choice of woods, which was quartersawn bubinga and quartersawn paduak. I had to look up what quartersawn was: the log is first cut into quarters, then the boards are cut by cutting parallel to the tree's rings. Eric said that "the quartersawn material was specifically chosen for it's dimensional stability, strength and beauty." Well it certainly looked nice!

I was interested to see how challenging this puzzle could be: it did not have any sliders as far as I could tell from the picture of the box open, so it was 'simply' a series of sliding panels. As I started to move the panels around, I was definitely impressed with the design. The first few moves were not too hard, but then you end up at a dead end. After a bit of fiddling, I figured out the next move, which is where the 'Tier' part of the name comes from.

The next few moves are also quite tricky, and make use of this new interesting move several more times. Eventually, the box opens, but to my surprise the end which I thought was the bottom ended up being the top! I admired the nice finish on the inside of the puzzle as well. I think it took me about 10 minutes to open the box, which was pretty low in terms of dollars per hour of puzzling enjoyment, but the craftsmanship is superb!

I then proceeded to close and open the box a few more times, until I felt like I had a good understanding of its complexity. It is definitely an interesting box. Funny enough, in putting it back together I discovered an interesting move that I probably was supposed to use when opening the box, but I managed to get by without using it. This was unfortunate because it is a pretty cool idea and one of the two very unique features of this box.

I think the only downside to this box is that the fit is a bit loose. The panels had a tendency to slide of their own accord, which, if you don't notice it, can be confusing. I found it best to lay the box on its side so that the panels didn't do this and I could fully appreciate the moves required to open the box. Still, it is a very cool box that I am happy to own.

Tomorrow, a disentanglement puzzle that I purchased in the hopes that it would help me defeat my puzzle nemesis.

From Matchsticks to Magic (Part 2)

In my last entry, I started writing about my experience at a mechanical puzzle talk given by Saul Bobroff and Chris Morgan that was organized by Eureka Puzzles.

After Saul finished his presentation, he handed it off to Chris.  Chris passed around sheets of paper that had number printed on them, and the objective of the puzzle was to fold the paper so that the numbers were in order from 1-8 from top to bottom. I was surprised that it actually ended up being pretty tricky: I figured out one of them but didn't get a copy of the second one.

Chris also did a demonstration of a puzzle/magic trick that involved a piece of paper with a door cut out of it. One side of the paper was decorated like a garden, and the other side was blank. He asked a volunteer to come up to help with this trick. He had her grasp the door on the paper and told everybody to close their eyes.

A few moments later, when we were asked to open our eyes, he had manipulated the paper so that it seemed as though the volunteer's hand passed through the door and ended up on the other side with the garden. This at first appears impossible, but if you think about it for a bit you can probably figure out how it was done. Finally, he concluded with the magic trick that he was practicing before the presentation started.

After the presen-tations were over, folks roamed around and played with all the puzzles that Chris and Saul brought. I first tried Spanner by Kirill Gribnev, which was made out of a full-size wrench, a chain, and a metal ring. Not too tricky, but a fun little puzzle that was nicely made.

There was also a large version of a nail puzzle around that I gave a try. I have no idea what it is called, so unfortunately I can't find a picture. It was quite large with maybe foot long nails that were a quarter of an inch thick. Definitely a good choice for this type of event, because it is almost indestructible.

Saul had some of his impossible objects as well, including Nine Drilled Holes, which I hadn't seen in person before. It is actually quite small, maybe a bit more than an inch square. It is very nice looking, as you can see from the picture. The idea is that there are nine holes drilled in the acrylic block, all but one of which are curved. The question is, how does one drill curved holes? They were actually drilled, according to Saul. Quite puzzling!

I also got to see 4 Street Elbows in person: it consists of four elbow joints that are connected in a circle. How could it be possible to add the last joint? I have a theory about this one, but with impossible objects you haven't really solved it until you have duplicated the feat. Saul said that the pipes are held in place only by the threads.

There were a bunch of other puzzles, but the one that stumped me was Mmmm puzzle by Hirokazu Iwasawa (Iwahiro), the same designer who made ODD Packing Puzzle, a very cool and award winning packing puzzle. Mmmm is quite simple: it consists of a box with a lid and four identical M-shaped pieces. The objective is to place all of the pieces in the box and shut the lid.

I had no luck with this, even though I worked on it for a good 10 or 15 minutes. In fact, I couldn't even get three of them in, which Iwahiro suggests as the first problem to attempt. I would guess that once you get three in, it is not trivial to figure out how the fourth fits, since he describes these as two separate problems.

I really wish I could have spent more time with this one, because I'll bet the solution is interesting. Unfortunately, these are sold out on the two websites that Iwahiro suggests, hopefully more will be made at some point.

After people were done hanging out after the presentation, everybody headed over to Eureka to see what was for sale. We ended up playing around with some copies of Perry McDaniel's Petite Fours, which were very cool. I solved three of them, but couldn't figure out Cinnamon Walnut Twist Cake. I am on the waitlist for the batch Perry is producing in December, so I guess I'll have to wait until then.

It was great meeting Saul Bobroff and Chris Morgan, and I also met Tim Udall and a few other collectors in the area. A very fun evening, I was glad that I was able to make it. Hopefully this will be the first of many puzzle gatherings I will attend.

Tomorrow, I'll write about a very nice puzzle box that I purchased from Eric Fuller.

From Matchsticks to Magic (Part 1)

Eureka hosts a weekly game night on Tuesdays, and one week back in September they had a talk on mechanical puzzles and the overlap between puzzles and magic. The presentations were going to be given by Saul Bobroff and Chris Morgan, both of whom I had heard of but hadn't had the chance to meet yet. In addition, this would be the first puzzle event I attended.

When I arrived, things were still being set up, so David introduced me to Saul and Chris. Saul was laying out some of the puzzles he brought and handed me a puzzle to try. It was a small wooden puzzle that had something that resembled a ship's wheel pivoting on top of a base. The objective was to remove the wheel from the base. I solved this one pretty quickly, since the mechanism is what I expected it to be.

Saul thought that one would be pretty easy for me, so next he handed me an interesting little 2d packing puzzle. If I remember correctly, it consisted of packing eight right triangles (non-isoceles) and a rectangle into a square shape. This one took me a minute or two, but I figured it out after a bit. Pretty cool!

Next I was introduced to Chris Morgan, who was working on his magic tricks for the evening's presentation. It was a self-working card trick that was pretty cool. He had a number of puzzles that he brought as well, but the presentation was ready to start so I found a seat.

There we a good number of people at the event, I didn't get a good count but there were probably at least 40 people. Lots of families with kids and such, which was great. More young puzzlers in the making!

Saul started off the presentation by talking about the different types of puzzles. He handed out a sheet that outlined the Slocum classification to help people follow along. He had brought examples of almost every type of puzzle and explained the objective and other sub-types of puzzles that fit into the same type.

Next, he started the interactive part of the presentation where he showed us a matchstick puzzle on a magnetic matchstick board that he brought, and we got to try to solve it on our own. Each table had a number of sticks that could be used for the problems.

In case you're not familiar with them, matchstick puzzles usually consist of a starting position with the matchsticks arranged in a particular shape, and an objective, which usually specifies both the ending shape (or qualities of the ending shape) and the number of sticks that can be moved. If you search the web, you can find a ton of this type of puzzle, which can range from quite easy to very tricky.

This was a lot of fun and got the kids involved. The first person to solve a puzzle was given a prize: their own set of matchsticks so they could play at home.

I ran out of time to write this entry today, so stay tuned for the exciting part two tomorrow!

Bowling Alley in a Briefcase

I went down to Eureka to pick up the DanLock that I had loaned to David one day. He had recently returned from the 2009 International Puzzle Party, and had all sorts of new puzzles to show me. I saw a few of Allan Boardman's tiny burrs, an original Stewart Coffin, Ring Box by Gary Foshee, and a ton of other stuff.

David was kind enough to offer to loan me a copy of Norman Sandfield's Bowling Alley in a Briefcase by Kathleen Malcolmson. I had seen this type of briefcase design before, there are several types, and was excited to have the opportunity to give one a try. I had no idea what to expect, other than that it would be quite challenging.

I worked on this puzzle for quite a long time: I am not particularly experienced with hidden mechanism puzzles, so I think that contributed to its difficulty. I shook in around all sorts of ways and had a hypothesis about what was going on inside the briefcase from the noises I heard, but I had no luck getting it to open!
This continued night after night, working on it for an hour or so each night for about two weeks before I finally broke down and asked David for a hint.

I told him all of the things that I had tried and my hypothesis about the workings, and he gave me a hint that I thought gave away the solution. When I tried it, however, it still failed to open! I tried that night for about an hour, and even with the hint, it still wouldn't open, which was fairly frustrating.

The next morning, right after waking up I went straight back to that briefcase. Finally, something clicked (mentally), and I figured it out. Now that I know how it works, it seems so simple, but it is a real challenge to figure out what is going on inside when you can't see. This is a very cool puzzle, but was quite a challenge: not for the faint of heart! It is very nicely made and well designed, a thoroughly enjoyable puzzle.

Tomorrow, I will write about a presentation on mechanical puzzles hosted by Eureka, where I met a bunch of Boston-area mechanical puzzle collectors.

50-Move Makishi Puzzle Box

As I mentioned previously, I have been corresponding with Matthew Dawson, an avid collector and designer of puzzle boxes, for a while. It was great hearing about his collection, which has hundreds of very cool puzzle boxes, and what he thinks about various puzzles. He knows that I like to get a lot of puzzle for my money, so he suggested that I consider buying a puzzle box from Makishi, who has created a series of some very interesting puzzle boxes.

They have the traditional Japanese puzzle box mechanism, but he has done a great job designing the keyways to make for an interesting puzzle. Also, they are not made from fancy wood or yosegi, so they are quite reasonably priced. Makishi tries to keep the prices low so that his boxes are accessible to more people, which I definitely appreciate.

He makes boxes that range from 8 to 50 moves, and I decided to purchase the 50-move box, on Matt's recommendation. He knows I like a good challenge and thought that this one would keep me busy for a while. Makishi lives in the US, so my box arrived a week or so after I mailed my check to him. I was very excited since this is the first box in my collection that requires so many moves to open.

It had a nice finish with "makishi handcrafted" branded on the side of it. The action was nice and smooth. I was surprised that the box could have 50 moves with only two sliding keys. I played around with it for a while and figured out a few moves, but then got stuck. I took a break after about 20 minutes of trying, so I could approach it with a fresh mind later.

After about 20 minutes of trying to ignore the box, it was too tempting and I had to give it another try. This time, after a few minutes, I found a move that I hadn't previously noticed. It was tricky! Even now that I was making progress, it took me about 25 more minutes to get the box completely open. I was very impressed with the thought that went into it and enjoyed it very much.

Only the top panel is removable, the other three movable panels are not removable unless you take out a small screw that Makishi has put in the bottom of the box. Matt told me that Makishi said not to remove it, so I didn't.  Good thing he told me, because I would have been tempted otherwise! I think the panels fit on fairly tightly, so it might be tricky getting them back in their grooves or something.

Overall, I would highly recommend this box. I haven't tried the rest of the series, but I would definitely consider purchasing the rest after my great experience with this one. He doesn't have a website, but he can be reached by mail. I probably shouldn't post his address publicly, so let me know if you would like me to email it to you.
 
Tomorrow, I'll write about my experience with a Norman Sandfield puzzle that was loaned to me.

Update: Fellow blogger Oli posted a review of the 50-move and 30-move boxes, check it out!

Bits and Pieces Puzzle Boxes

I was looking around on the web for some affordable puzzle boxes, and read about some boxes from Bits and Pieces on Jeff Chiou's blog, MagicPuzzles. I browsed on over to Bits and Pieces to take a look at the boxes he described.

I had seen their site before, but it was hard to pick anything specific out without a recommendation since they have so many items. Jeff said Snap Latch Box was good, as was Matchbox, so I decided to purchase those. I had spoken to David from Eureka about Brass Treasure Chest, and he mentioned that he thought it was the best of the Bits and Pieces brass series, so I decided to purchase that one as well. Finally, I thought I would get Magic Money Box, since it is an often seen design that I've never played around with.

A few days later, I had my new puzzles and was ready for some wild and crazy puzzlin' fun. I started with Magic Money Box. Much to my disappointment, once I removed the plastic wrapping, a chip fell off! As I rotated the puzzle around to figure out what was up, the secret drawer slid right out! Damn! So much for an "A ha!" moment. What a shame! If the puzzle functioned correctly, I could see how it would be a pretty tricky puzzle, though it really depends on a good fit.

I was heading up to Maine to go sailing with my parents for the weekend and ran out of time on the others, so I decided to take them up to the boat with me. Sailing and puzzles, what a way to spend the weekend!

Once we got on board the boat, I set myself to solving Snap Latch Box. The finish and wood are quite nice, overall a well made puzzle. I played around with it for about 15 minutes, shaking it and trying to figure out how it could open, when I finally figured out what to do. This has a very clever mechanism that is quite satisfying once you figure it out. I couldn't help but chuckle when the box finally opened. I agree with Jeff that this is a great box for the money.

I worked on both Matchbox and Brass Box for several days, but so I don't confuse you I'll just talk about Brass Box first. I played around with this one for quite some time. Unfortunately, in wiggling the various parts, one of the legs fell off! I initially thought that this was part of the puzzle, but it turns out that it is not. Fortunately, this did not effect the operation of the puzzle at all.

I worked on this one for 3 or 4 hours when I finally figured it out. The solution is quite tricky and I'm pretty thrilled that I was even able to figure it out. It was very satisfying when the lid finally opened, but it takes quite a bit of patience.

I should mention that it is a reproduction of a puzzle designed by Rocky Chiaro, a retired machinist who makes some very cool looking puzzles out of brass. Unfortunately, his stuff is a bit expensive for me at the moment, so this reproduction fit the bill nicely. A little J.B. Weld and the leg would be as good as new!

Finally, the Matchbox: I must have spent something like 10 hours shaking and rattling this puzzle every which way. I could hear something going on inside and thought that I had figured out some moves that were making progress, but I had no luck getting the darn thing to open. I had all sorts of crazy theories about how it could open, but nothing worked. This was particularly maddening, because I was out on a boat in the middle of the ocean in Maine, so there was no help available!

When I finally got home, I asked my girlfriend to take a look at the solution and let me know if I was on the right track. She read it over and said that I had the right idea, so I kept working on it for another hour or so. Eventually, however, we determined that there was a piece missing! This really ticked me off because I had spent so long on this damn puzzle. Sure enough, when I improvised the missing piece, I solved the puzzle in no time at all. You can imagine this was quite frustrating since not only did I not have the enjoyment of successfully solving the puzzle, I also spent a ton of time on an unsolvable puzzle!

Still, the puzzle in its complete form is quite clever: I would recommend it. The one caveat is that you may want to get a third party to inspect the puzzle to make sure that it works properly before you spend 10 hours trying to solve it.

Allow me to summarize: I ordered four puzzles. One was broken, one broke after a minute or two, and one was shipped in an unsolvable state. No wonder Bits and Pieces has a crappy reputation! I wrote them an email suggesting that they replace the three puzzles and give me a $20 store credit, which I thought was pretty reasonable. They replied saying that they would ship the three puzzles to me along with a $10 store credit, and that I could keep the broken puzzles. This was fine with me, since they were all really easy to fix, so now I have two copies of each!

Overall, it was a bit of a disappointment, but I would still order from Bits and Pieces again. Their prices are so low, I can get past the low quality. Plus, they handled my dissatisfaction quite well, which is admirable. They must be accustomed to it! I will just have my girlfriend solve the puzzles using the instructions next time to make sure a broken puzzle doesn't spoil the experience for me.

Karakuri Cube Boxes

After seeing photos of Perry McDaniel's awesome Petite Fours from the 2009 International Puzzle Party, I got a hankering for some more puzzle boxes. I emailed Perry and he said that he was sold out for the moment, so I got on the waitlist for his December production run, I can't wait!

I got a tip from Peter Wiltshire that the Karakuri Cube Boxes were pretty cool as well, and a great deal for the money, so I ended up ordering those from PuzzleBoxWorld.com since Karakuri was sold out. Unfortunately, they were out of stock on #2, so I ended up getting #1, #3, and #4.

The shipping was incredibly fast, I think I had them in two days or so. It would be pretty tricky to tell these boxes apart since they all look so similar, but each one is packaged with a little slip of paper that tells you which number it is.

I am an organized kind of guy, so I decided to do them in order. The first box is made out of keyaki (zelkova) and maple on the outside. These boxes are different from the small box series because they do not have any identifying marks to indicate where the top of the box is, and they are cubes so it is quite easy to lose your orientation.

The #1 took me a few minutes of wiggling things to try to figure out what would move. I think it took me about five minutes to open it: the solution was pretty cool. This ended up being my least favorite of the three. I enjoyed it at the time, but by comparison it is not quite as cool. I was still delighted when it finally popped open.

Next I tried the #3, which is made out of walnut and maple on the outside. The #3 was not too difficult compared to the #1, but the movement is pretty cool. You wiggle it around all sorts of ways, and then all of a sudden something works. Then the actual opening mechanism is quite cool as well. This one is my favorite of the three.

Finally, I tried the #4, which is made out of karin and maple. This one is similar to the #1, but the way it opens is a bit more unique. The moves seem quite random, but when you finally open the box you realize what the mechanism is, which is pretty unique. I think this one was my 2nd favorite, it is also very cool.

Overall, these are great boxes that I would recommend! The only downside that I could think of is that non-puzzle people can be tempted to use their nails to slide the pieces, which can scratch up your nice boxes. The action on these is quite smooth, so gentle pressure is all that is required. The inner edges of the cubies are beveled which helps you get a grip, so nails are not necessary.

I'm planning to purchase #2 when it becomes available again. Any thoughts on this one as it compares to the others?

Tomorrow, I'll write about four puzzle boxes that I got from Bits and Pieces. Can you guess what happened?

Twisty Puzzle Spending Spree

As you may recall from my second post, my mechanical puzzle obsession actually started with an order from ThinkGeek.com: I ordered a Legend of Zelda t-shirt and decided to buy a few Hanayamas, which kicked off this whole wild ride into the land of the mechanical puzzle people. Anyways, I follow ThinkGeek's RSS feed for new items and items that are on sale, and they were having a sale on V-Cube 7's for $45, which was a good price for them as far as I could tell.

So I decided this would be a good time to give one a try and test whether or not I could generalize my knowledge about 3x3x3 to solve a 7x7x7. While I was there, I noticed that ThinkGeek had a few other twisty puzzles that were pretty reasonably priced too, so I ended up buying Megaminx, Rubik's Mirror Blocks Cube, and a knockoff Square-1 named Irregular IQ Cube. I thought that I might as well confront my fear of twisty puzzles head on! I guess I am kind of a sucker for a sale, and it worked just like retailers hope: the sale brought me in and I ended up buying more than I expected. And, to top it off, the V-Cube 7 is still on 'sale' months later!

When my puzzles arrived the first one I started with was Mirror Blocks, because I thought that it would be just like a 3x3x3, but somewhat harder to tell what the hell was going on. It is a really remarkable puzzle: nice smooth action, and it looks amazing when scrambled, like a piece of modern art. It is quite cool how the seams still line up no matter which way you turn the cube, which is somewhat baffling at first.

After toying around with it for a bit, I gave it a good scramble and tried to solve it. It is quite daunting once it is scrambled up and took me a while to get oriented. I decided to use the thinnest side as the bottom and work my way up. I studied the proportions of the pieces carefully as I made each move, and eventually was able to reassemble the cube. What fun! I scrambled and solved it a few more times just because it was that cool.

Next I tried the Square-1 knockoff. This was a very cheaply made puzzle: in fact, they send you two for the price of one! That was a good thing, because the stickers were falling off one of them like crazy. I glued them back on and worked on the second one while the first one was drying. This was quite disappointing though after my great experience with Mirror Blocks. The puzzle did not turn smoothly and jammed quite easily, but at least it was only $10 for the two of them. You get what you pay for!

This puzzle was quite baffling to me. I had trouble even getting it back into a square shape, much less getting the colors back on the right faces. I was able to get it back to a square and partly solved, but then I got stuck.  I worked on it for a few more days and haven't really spent much time on it since. I think if I had a better version I would be more likely to play with it, but fighting this one as it jams isn't a lot of fun. I'll probably buy an actual Square-1 in a while and see if I can figure it out.

After I had given up on the Square-1 for a while, I turned to Megaminx. I had no idea how difficult it would be, but thought that I could probably figure it out. The ThinkGeek Megaminx is not very good quality, it jams quite easily, which is unfortunate. This made it a bit tricky to scramble because of the number of faces and the frequency of the jamming, but eventually I got it mixed up pretty well.

I picked a random face to be the bottom and started to work my way toward the top. It was quite a challenge, especially with the large number of colors and I frequently screwed up and messed something up that I had previously solved. Eventually I figured it out though, I think it probably took me about two hours. The hardest part is getting the final pieces in place, because you need to do it without messing everything else up. I tried a bunch of moves and eventually found one that was similar to a 3x3x3 move that I used for a similar purpose, and it ended up working. Nice!

Finally, I tried to conquer the 7x7x7 V-Cube 7. This is a really daunting puzzle if you're not a twisty puzzle nut: just the sheer number of cubies is ridiculous. I played around with it for a bit, making patterns and whatnot. The action is very smooth, which was a delight after playing around with the cheaper twisty puzzles. It is definitely worth the extra few bucks to get a decent twisty puzzle: cheapo ones are a pain in the butt.

Eventually I decided to go for it and scrambled it up. If it looks daunting when solved, it was even more so when scrambled. I decided that my strategy was going to be solving the faces first, then the edges, then the corners. I worked my way from the center of each face outward in concentric squares, getting the 3x3 solved on each face before proceeding to get the 5x5 square solved and so forth. This took me a very long time. I didn't time myself, but it was probably 3-4 hours. I developed a little set of moves that would cycle three pieces between adjacent faces that worked pretty well, but it took a very long time to position each piece individually.

Next, I moved on to the edges, which weren't too hard...at first. Once I got to the end, I realized that my move was a 3-cyle and I need a 2-cycle to finish! (A move that would switch two edge pieces). Try as I might, I couldn't find a move that would break the 2-cycle. I kept ending up with other configurations that just reduced to a 2-cycle. Eventually by trying a move similar to a 3x3x3 move that is a two cycle, I managed to get the edges in a state where they could be solved by my 3-cycle move. I think this whole process took me about a week of working on it for an hour or two per day. Needless to say, I was quite satisfied when I finally figured it out.

Now came the easy part! With the edges solved and the faces solved, I could treat it just like a normal 3x3x3 cube. Needless to say, I was very careful, but after a few minutes I had it back to the solved state! I was quite pleased with myself!

That said, I haven't tried to replicate this feat since I have solved it. Writing this makes me remember how repetitive it was! I think it would be just as satisfying and interesting to do a 5x5x5 and it would take quite a bit less time. If you know how to do a 5x5x5, you pretty much can do a 7x7x7, so if I had it to do over again I might just do that instead. Still, it is kind of cool to say I have solved the 7x7x7!

You  might note that I didn't mention the 6x6x6, that's because my understanding is that even cubes are somewhat different from odd cubes because there is a parity problem that can occur. This seemed like an added annoyance that I would rather not deal with, which is why I haven't bothered with even cubes other than the Triple 2x2x2 I blogged about a few days ago.

Whew! I didn't think I was going to be able to get this entry done in a single night, but I was on a roll. Hope you enjoy it! Tomorrow I'll write about some more Karakuri boxes!

Cast Coaster

A week or so after trying Cast Ring, I was back at Eureka looking for another puzzle. Since I had a good time with Cast Ring, I decided to try Cast Coaster next. This was also the last level four Hanayama that I didn't have.

Cast Coaster, designed by Serhiy Grabarchuk,  is similar to Cast Ring in that it is not possible to completely disassemble the pieces. There are three rings that are interlocked, and the task is to disassemble the rings (trivial), and put them back together so that it all lies flat. Though it is flat like a coaster when solved, it probably wouldn't make a good coaster unless your glasses have wide flat bottoms, because there is a hole in the center that could cause tipping.

It was a Friday, which is the night I usually go swing dancing with my girlfriend, so I only had a few minutes to work on the puzzle before we had to leave for the dance. I decided to throw it in my backpack just in case. In case of what? Good question.

We got to the dance and it was a lot of fun, but in the back of my mind I knew that puzzle was sitting there in my backpack unsolved. My feet were getting tired, so I decided to stop dancing just for a minute to go see if I could finish the puzzle.

I sat down in the walk-in coat closet and worked on it for about 15 minutes, I'm sure the people who saw me sitting there as they came in to get their coats must have thought I was nuts. Eventually I figured it out, which was quite satisfying because of the way the pieces all snap into place when you have them aligned correctly. Unlike Cast Ring, this one does not fall apart easily because it fits tightly which I liked.

This puzzle is only moderately difficult, as one would expect from a level 4/6, but it definitely does make you think. Like Cast Ring, it is not one that you are likely to solve by chance.

Tomorrow, I'll write about a little twisty puzzle spending spree!

Cast Ring

I was down at Eureka trying to find a good puzzle to buy next. I was talking to David, the owner, and telling him how I had pretty much run out of difficult Hanayamas to solve, except for the Cast Ring and Cast Ring II. I told him that for some reason this type of puzzle didn't really appeal to me: I thought it would be more annoying than enjoyable. David said that Cast Ring was actually a pretty fun puzzle, and suggested I give it a try since he had an opened version behind the counter.

I couldn't resist the opportunity to give it a shot, so I set myself to the task of trying to re-assemble the ring. I worked on it for about 20 minutes and was starting to be convinced that there must be some flaw in the puzzle. I concluded that there were only a few ways for the pieces to fit together, and since they didn't fit flush there must be a bent piece or something. I asked David and he turned around and was able to solve it, so there went that excuse! He handed it back to me and I resumed working on it.

I tried for another 10-15 minutes but needed to get going, so I decided to buy puzzle. I had them disassemble it for me, since it comes assembled and I didn't want to accidently discover the solution while disassembling it.

I worked on it a bit more on the ride home on the subway and eventually figured it out, much to my satisfaction and relief! It is definitely a cool little puzzle: one thing that I liked about it is that I really had to think about the different possibilities for how the pieces could fit together to deduce the solution. It is probably not one of those puzzles that you will solve by idly fiddling with it, which I think is a positive trait.

The puzzle is quite well constructed, though it would be nice if there was a clip or magnet to hold it in place since it tends to fall apart. I like the dual-toned finish that they used. Overall, a cool puzzle that I would recommend.

I would imagine that it is better to first experience a puzzle ring in this enlarged form rather than a traditional puzzle ring, since it is easier to see what is going on. That said, I haven't actually done a small puzzle ring, so who knows! I would wear a puzzle ring, but I already have a ring that is a gift from my grandparents that I wear, and I think a second piece of man-jewelry would be too much. Maybe I'll get my girlfriend to wear one and I can play with it!

Facing My Twisty Puzzle Demons

I was hanging around Eureka thinking about buying a twisty puzzle of some sort. Back in college I had learned an algorithm to solve the 3x3x3 Rubik's Cube, but I had never solved it on my own. Now that I'm really into puzzles, I wondered if I would have been able to do it without help. I doubt it, but who knows!

Anyways, I was looking for something a bit different to try out my sequential/twisty puzzle skills: I had the fear that I would be terrible at them, so had been avoiding them up to this point. I was thinking about getting a Triple 2x2x2 Cube, but when I talked to David, the owner of the store, he recommended that I give Cmetrick Too a try. It looked like an interesting little puzzle so I decided to give it a shot.

It is a bit tricky to imagine how this puzzle works, but I'll give it a try: there are four balls enclosed in the frame, each of which has six colored discs, four of which are visible. Adjacent balls share a disk that is not visible, because it is hidden by the frame. The disks are double-sided and are the same color on both sides. To manipulate the puzzle, you rotate the balls, which exchanges the position of the disk.

The picture on the left shows one of the balls moving toward the southeast corner of the picture. The little sliver of white between the green and the yellow discs is the 'hidden' disk. As the ball continues to rotate, this hidden disk will end up at the top, and what was on the bottom will end up in the shared/hidden position between the southern ball and the eastern ball.

The objective of the puzzle is to get each ball to be all one color, with the white discs in the hidden positions between the balls. An alternate objective is to get each face the same color, like all blue on top, all green on the bottom, all red on left/right, and all yellow on front/back, with the white faces hidden.

I set about trying to achieve the first objective, and it took me about 10-15 minutes to solve it. Not very hard at all! I was a bit disappointed because I was hoping for a bit more of a challenge. I tried the second objective, and it wasn't any more difficult. Oh well! It was still fun, but easier than I expected. I thought the mechanism was pretty cool: the way the pieces exchange is nicely done.

There is a harder version of this puzzle called Cmetrick Too Hard that has colored dots in the middle of each disk that uniquely identify each disk. The objective on this is the same as the Cemetrick Too, but all the dots must match on the top, bottom, left/right, and front/back. I haven't tried this version yet.

It was only about noon at this point and I had nothing else to do for the day, so I decided to head back to Eureka and pick up something that was hopefully more difficult. I ended up purchasing the Triple 2x2x2 Cube, which I thought would keep me busy for a while.

My thinking was that if I only scramble one of the 2x2x2's, it would just be a somewhat awkward 2x2x2. That way, it could be like a graduated puzzle where first I try to solve 1, then I try to solve 2, then I try to solve all three. Hopefully this would keep me busy for a while!

First I scrambled just one cube and worked on solving that. It took me a little while, but I was able to adapt the algorithm I used for solving the 3x3x3 after a bit of fiddling. Because there are no centers or edges, it is possible to end up with a parity issue that can't be addressed with the algorithm I know, but I just got around this by fiddling with it for a bit and eventually the parity issue went away. Not the most graceful approach, but it worked (eventually).

As expected, scrambling and solving the full puzzle wasn't really any different, it was just somewhat repetitive. I found it easiest to solve the two ends first and then solve the middle, because it is a bit easy to get confused when the end cubes are scrambled. I made a lot of mistakes so it took me a while, but eventually I solved the whole thing.

The construction is not perfect, but it doesn't have the nice smooth operation of a standard rubik's cube. It jams up fairly easily and there are gaps between the cubes that you can see. It is quite cheap though, so that makes it ok by me! Overall a fun little puzzle.

Iwahiro's Dinghy

I was down at Eureka Puzzles and Games, a local puzzle shop I frequent, shopping for a new puzzle to keep me entertained. I had been eyeing a nice looking little puzzle in the display case called Dinghy. It was designed by Hirokazu Iwasawa (a.k.a. Iwahiro), who was also the designer of the award-winning and very cool ODD Packing Puzzle that I had purchased a few weeks ago (blog entry).

I spoke with the owner of Eureka, David, and he said that it was an interesting puzzle that has a nice little twist at the end. I liked the sound of that, so decided to give it a try.

The puzzle is quite well made and sturdy, though it has a delicate appearance. The chain is a very thin bead chain that gives it quite a bit more flexibility than a more coarse linked chain. Also, it has the advantage of not tangling as easily. The fastener on the end is crimped to keep you from cheating.

The puzzle itself was a lot of fun to solve. It was of moderate difficulty; I think it took me about 20 minutes to solve. The structure of the frame is a bit daunting at first, I needed to look a it for a while before I could think of a way to approach it. I hit a dead end for a while where I felt like I had tried everything, but eventually I figured out the key move that led to the solution. The last move wasn't difficult, but it is a really cool move that requires the exact amount of chain that is provided, which I thought was a very nice touch.

Overall, a very cool puzzle that I would recommend.

Laser Cut Burrs

As I mentioned in a previous post, a while ago I found an open access fabrication lab that has laser cutters available for public use. I decided that it would be interesting to make a few board burrs, since they can easily be cut out of a flat sheet of wood with a laser cutter. The first one I tried to make is a variation on a puzzle I had seen on Pavel Curtis's website, PavelsPuzzles.com, which he calls Six Tabbed Planks. You can buy this nice looking acrylic version from him here.

Pavel happened upon the design while at the 19th annual International Puzzle Party. Part of the party included an excursion to see Edward Hordern's puzzle collection: he had one of the largest puzzle collections in the world! (Unfortunately, Horndern passed away back in 2000.) At Horndern's home, there was a huge tent set up with tables and various puzzles from his collection on the tables. Pavel found Six Tabbed Planks on one of these tables. He couldn't solve it in the time that he had, so he decided to jot down the design for later reference. This slip of paper remained in his wallet for six years until he finally got around to having the puzzle made.

Interesting story, eh? Unfortunately, nobody knows who the designer is, but it is a cool little puzzle. I think it looks very nice in the acrylic that Pavel used, but my material at hand was plywood, so that is what I used!

The design I ended up making is a variation on this design by David Rousseau named "Pavel's Search" that I found on Ishino's site, Puzzle Will Be Played. The structure is similar, but it is a level five burr, meaning that five moves are required to remove the first piece.

This design is quite simple to make using a vector drawing program, so I sketched it up and set the laser cutter to work. It took a bit of calibration to get the holes to be the correct size for the tabs, since the width of the laser is not negligible when it comes to a precise fit, but eventually I got it right.

I decided to stain the wood and finish it with wax to give it a darker tone. In hindsight, I think the natural wood probably would have looked better. Oh well! It is definitely a cool little puzzle. Some burrs are very difficult due to the large number of pieces and potential assemblies. This has six pieces, two assemblies, and one solution.

An assembly means that all the pieces will fit together in a certain way, but not necessarily that you could physically manipulate the pieces to arrive at that assembly. For example, two solid rings could physically be interlocked if you could magically teleport them together, but there is no physical way to assemble them in this manner without breaking things. This is an assembly without a corresponding solution.

If there are lots of assemblies but only one solution to a burr, it can be quite challenging to determine which assembly is the correct one. Basically what you can do is think about a given assembly and see if you can figure out how to disassemble the burr to the point where you can add the final piece in. (I say this like it is a rule, but that's just the way I do it. How do you do it?). So the reason this puzzle isn't too hard is that you there are not too many assemblies that you need to try. Also, three of the pieces are identical which also reduces the amount of trial and error.

Ok, that was a big detour considering that most of you already know that, but I thought it would be fun to try to explain it. Did it make any sense? I hope so.

The second puzzle I decided to make was Chocolate Dip Burr by Bill Cutler and Frans de Vreugd. This was a design that I had also seen on Ishino's site, Puzzle Will Be Played, back when I was doing a lot of burrs with LiveCube. This is a very cool puzzle because without the coloring there are 21 solutions of varying levels (number of moves to remove the first piece), but if you arrange the pieces so that half of the burr is dark and the other half is light there is only one solution (with 16 assemblies). This solution requires 13 moves to remove the first piece, so this is quite a challenging puzzle.

This puzzle was also a breeze to make with the laser cutter. My file was corrupted and I was able to redo it in about 15 minutes, just to give you an idea for how easy it is. I made it out of 1/4th inch plywood, which results in a fairly tiny puzzle, but the laser cutter doesn't work as well on thicker material. To finish it, I stained half of the puzzle to make the dark side and left the other half natural for the light side.

It was a bit tricky to half-stain these tiny pieces but I came up with what I thought was a pretty clever solution. I actually dipped the half-stained pieces in the stain, but to prevent the stain from wicking up the wood past where I wanted it to go, I used a knife to score the line where I wanted the stain to stop. That way, the stain would wick up just to the point where I wanted it to stop! It worked like a charm. I polished the finished puzzle with some wax.

This puzzle was a real beast to solve. I worked on it for a few days without much luck, but eventually figured it out. Even though there are 16 assemblies, some of them are clearly impossible, so you can dismiss those right away. Some of the moves were pretty tricky, especially considering I haven't done many board burrs, so it took me quite a while. This type of burr can be very challenging!

Tomorrow, I'll write about a nice little two-piece disentanglement puzzle from Japan with a really cool final move.

The All Five Puzzle by Wayne Daniel

After a nice morning of sailing on the Charles River, my girlfriend and I were walking up Charles Street to get some food. We were glancing at the windows of the shops as we walked by, when I noticed a familiar looking puzzle: it was a striped icosahedron! I had seen this puzzle, All Five by Wayne Daniel, before for sale at CubicDissection.com, and considered buying it, but just hadn't gotten around to it yet.

The funny thing was that this wasn't a puzzle shop, nor did they carry any other puzzles, just this one! We walked in, hoping I could save a bit of money on shipping, and inquired about the puzzle in the window. The store clerk said that they actually only had that one copy and that it was broken. Oh well! I thanked them and we headed on our way.

As we walked down the street a bit, I thought to myself, "hey, I could probably fix it if it isn't broken too badly!" My girlfriend agreed that it was at least worth a look, so we headed back to the store. The clerk said that she had thought the same thing right after I left, and took the puzzle from the window for me to inspect.

It turned out that one of the pieces on the outer shell was broken, but could be repaired fairly easily. They gave it to me for 50% off, which was a pretty good deal for them, since who wants a broken puzzle? I was pretty happy to be getting a $40 puzzle for $20, so everybody was happy. When we got home, I repaired the puzzle and waited patiently for the glue to set.

Now a little info on this puzzle for those of you who haven't heard of it. It is an interlocking put-together puzzle that consists of 37 pieces. Using these pieces, one can construct the five platonic solids, which are the five solids that can be formed by regular polygons (regular triangle, square, and regular pentagon). These polygons are the tetrahedron (4 triangular faces), cube (6 square faces), octahedron (8 triangular faces), dodecahedron (12 pentagonal faces), and icosahedron (20 triangular faces).

According to Jerry Slocum, "This is the first puzzle with all the Platonic solids in a concentric, integrated and solid form, with no voids between them," so there was quite a bit of demand for this puzzle. It even had an article about it in the New York Times! Originally it was hand-crafted by Wayne Daniels, but demand was great enough that it was produced commercially by MI Toys. Of course, the copy that I found was a commercially produced version: the hand-crafted versions are quite expensive.

Once the glue dried, I started to disassemble the puzzle. On the outside was an icosahedron, which I think is the most interesting of the sub-puzzles that this puzzle contains. The pieces need to be put together in a particular way due to the angles of the pieces, which makes it fairly challenging. Of course, this is an assembly puzzle, so disassembling it is pretty easy.

Inside the icosahedron is a dodecahedron that comes apart into three identical pieces, which is also pretty cool. Inside the dodecahedron is a cube that sort of reminded me of your ubiquitous Snafoz puzzle. The fit on this was quite tight and I had to pry it apart.  Inside the cube are four small tetrahedrons, twelve quarter-octahedrons, and one big tetrahedron. The big tetrahedron contains four tiny tetrahedrons and a tiny octahedron. Whew!

Now that I had the puzzle apart, I tried to get it back together. I won't go into too much detail, since I'm sure your head is already spinning from all the "hedron" talk. Overall, it wasn't too tricky but it was a lot of fun seeing how the pieces fit together. I think putting the pieces back inside the cube is one of the most interesting parts, because it requires a bit of dexterity and creativity to figure out how to do it.

Assembling the cube is fairly straightforward but requires some trial and error, and the dodecahedron is pretty easy since it only has three pieces. The final challenge of putting the icosahedron together was a nice way to finish the puzzle off: it is definitely the most impressive of all the parts from a craftsmanship point of view, since it is an icosahedron with a dodecahedral hole in the middle.

Check it out if you haven't picked one up yet and enjoy assembly puzzles. Eric Fuller has plenty available at CubicDissection. All of these awesome photos are his, so hopefully I'll send a bit of traffic his way.

My copy fits together fairly well, though the fit isn't quite right on the icosahedron: there are some gaps between the pieces when assembled. My only complaint is that the 'quarter icosohedrons' sort of seem like cheating since they are not actually assembled into icosohedrons in the final puzzle. That said, I sure as hell don't think I could have done any better. Great puzzle!

Tomorrow I'll write about a few more puzzles I made with the laser cutting machine: one by an unknown designer and one by Bill Cutler.

Cast Dolce and Cast S&S

I went down to Eureka and picked up two more Hanayama puzzles and brought them home to give them a try. The first one I attempted was Cast Dolce, a design by Akio Yamamoto. This puzzle has a very nice appearance with a gold female symbol interlocked with a silver male symbol. The pieces are quite sturdy and have a nice finish.

I enjoyed solving this one quite a bit: similar to Cast Baroq, another Akio Yamamoto design, this one has a fairly lengthy solution. You keep thinking that you are close to the end when Yamomoto throws in another twist. When the pieces are finally released from each other, it is quite satisfying.

Putting it back together is slightly less challenging than taking it apart, though definitely not trivial since the solution is fairly long. One thing to keep in mind: you don't have it completely back together until the pieces are as shown in the picture above. There is a groove that allows them to fit together this way, and if the groove doesn't line up, you have a few more steps to go.

Overall, a great puzzle. I would agree with Hanayama's difficulty rating of 3/6 on this one. It took me about 5-10 minutes to solve. I brought this to a party yesterday and folks had a good time with it. The simplicity of an interesting two-piece puzzle is definitely appealing to non-puzzlers, I think.

The second puzzle I tried is called Cast S&S. This one is deceptively tricky. You need to pay carful attention if you want to really master this puzzle. At first, it may seem like the interactions between the pieces are somewhat unpredictable, but once you get an understanding of it, you will be able to figure this one out.

One downside to this puzzle is that it is not immediately obvious when it is in it's starting configuration. This has the advantage of making it more difficult to find the ending position, but I think that it is a bit dangerous since many people won't be starting from the start.

This puzzle has a nice copper finish, and is quite well made. I agree with the 3/6 difficulty rating on this one as well. Overall, a good puzzle!

Laser-cut Puzzle Box

Unfortunately, I didn't (and don't currently) live within easy access of any power tools, so my ability to build new puzzles was somewhat limited. I was searching the internet for fabrication labs, places where you can pay a fee to use various tools that could be used for prototyping, and discovered a place called the South End Technology Center at Tent City. This is a non-profit collaborative venture between the Tent City Corporation and MIT whose purpose is to provide free or low-cost access and training in most aspects of computer-related technology.

This might not sound particularly exciting, but in addition to classes on a number of aspects of technology such as word processing and web design, they also have two laser cutters and two CNC routers for open use! All you have to do is show up during Open Access Fab Lab time (Thursdays 5:30-8:30pm or Saturdays 1:00-4:00pm), and they have volunteers there who can get you started. Pretty cool, eh?

Well the first thing I thought was that it would be really cool to try to build one of Bruce Viney's puzzle box designs using a laser cutter, since his designs consist mostly of cutting plywood at 90-degree angles. This would make it fairly easy to create in a computer so a laser cutter could cut it out.

For my first project, I decided to try making Modified Matchbox by Peter Wiltshire, which is an alteration of Matchbox by Bruce Viney that makes the proportions a cube. I wanted to try making something more complex, but I thought it would be best to try something simpler to get the hang of things first.

The lab uses a program called Inkscape, which is a vector art program, to create the files that are sent to the laser cutter. Before I went to the lab, I created an Inkscape file that would cut out all the parts for Modified Matchbox, so when I arrived I just had to pop in a piece of wood and set it to print. The whole process was quite easy, and a few minutes later I had all the parts cut out. Now I just had to glue them together!

The results were decent but not great. I had assumed the kerf of the laser would be negligible, but unfortunately it was not, so each piece was slightly too small. The final box still worked, but it wasn't as good as I had hoped. You can see in the photo above that the top panel is slightly higher than the top of the front panel, which isn't ideal.

I finished it using some stain and wax, which unfortunately turned out a bit duller than I hoped it would. I was hoping that the stain would highlight the grain a bit more to give it depth, but no such luck. I had used plywood, so you can see the plys at the edges which also don't look too great. It would probably be better to use a proper wood that has been planed down to the right size, at least on the outside panels.

I tried another attempt a weeks later that turned out a bit nicer. I scaled up the pieces to account for the laser kerf and was quite careful to focus the laser before I started cutting. This helps reduce the width of the laser. I finished it just with wax, which I think looked nicer.

One of the biggest problems with using a laser is that it burns the wood rather than cutting it, so you are left with an ashy residue on the edge that must be sanded off. This isn't too bad when you just have a few pieces, but it is a bit of a pain having to sand every edge by hand. With the plywood I used, this residue is a bit sticky as well, so it is important to remove it for smooth operation.

Despite the mixed results, it was a lot of fun being able to build puzzles this way. There are a ton of interesting puzzles that can be built just with a laser cutter, so I just had to decide what I wanted to try. I'll write about some other attempts in later entries. Unfortunately during the summer the lab was only open on Thursdays, so I had to wait a whole week before I could try some more designs.

Tomorrow I'll write about two more interesting Hanayama cast puzzles.

The NeoCube

I stumbled upon a promotional video for The Neocube a while ago, and thought that it looked like a pretty cool thing to play around with. It is a creativity toy/puzzle that consists of 216 small magnetic spheres. You can use these spheres to make all sorts of shapes, including a 6x6x6 cube.

I think that the Neocube could be classified as a puzzle, because it is fairly challenging to figure out how to make it into a cube and other objects if you don't read how to do it. Unfortunately, I had seen a video on how to do it when I was eagerly anticipating its arrival, so I don't know how challenging it actually would be.

There are a number of base shapes that you can make, such as triangles, pentagons, and hexagons. These shapes can be combined to create interesting 3D shapes.  While triangles and hexagons lay flat, if you make a pentagon it ends up being concave, which is kind of neat when you combine them. Check out their website for more pictures of things you can make.

The best way to get a sense of how cool this is is just to watch this video:



Pretty awesome, eh? It seems a bit steep at $25, considering it is just a bunch of magnets, but I guess that is what magnets cost. I looked at websites that just sold spherical magnets, and the price ends up about the same.

I had a lot of fun playing around with these things. I would sit for hours on end just making different things. My girlfriend also had a good time with them, though she enjoys just mushing them around more. I definitely recommend them if you're into fiddly little creativity toys such as this. You might just surprise yourself, pretty much anybody I've handed these to has had a good time with them. Just keep them away from hard drives and credit cards!

Tomorrow I'll write about my first experience using a laser cutting machine to make a puzzle box.