I've been looking forward to writing this post, I hope you enjoy reading it! Here is a picture of the completed box. I was going to put it at the end where it should go chronologically, but I figure it is best to lead with a nice picture.
I think it was on the PuzzleWorld.org forums that I first encountered a link to Bruce Viney's website of puzzle box plans. After perusing the website and looking over some of the plans, I figured that it didn't look all that hard. Many of the designs were simply cutting various sized rectangles out of plywood, so I figured how hard could that be?
I was still home for Christmas so I had access to my father's tools and plenty of time on my hands, so I went down to Michaels Arts & Crafts and picked up some 1/8" craft plywood. While some folks may have started with Matchbox or one of the simpler designs, I decided to make the 25 Move Box. I figured that it was going to be quite a bit of work either way and I might as well go all out and make something complicated.
After carefully studying the plans, I quickly realized that cutting each part individually would take me a very long time (there were a total of about 65 parts that needed to be cut), so I created an excel spreadsheet of all the pieces, which I named and sorted by size. This allowed me to see which parts were the same width so I could cut a long strip of that width and then cut out the individual pieces.
Next, I laid out all of the parts in a PowerPoint document (yes, I am an Office junkie), so I could determine how to most efficiently use my $3 piece of plywood. That might seem insane, but I'm hard-wired for efficiency for some reason. In hindsight, this step was kind of a waste of time.
If you think that is crazy, next I planned out exactly the order of the cuts that I would be making in order to minimize the number of times I had to adjust the saw fence. This resulted in the document shown below (click to enlarge). Nice, eh?
It actually worked rather well, though there was one minor glitch that I was unaware of: I didn't have a micrometer! All my measurements were with a carpenter's ruler, so I made a bunch of cuts that were close, but not quite right (I ended up buying a micrometer to check). This was largely ok, because Bruce's design is quite forgiving, but the one place where it really hurt me was on the top and bottom panels. There are five pieces on the outside face of each panel, and if they are all too short by a tiny bit, when you line them up it is short by a noticeable amount.
So back to the shop I went and recut some of the parts. The rest were close enough or too large, so I was able to sand them down to size. I did not have a belt sander, however, so I filed them all down with a nail file. This was probably the most time consuming part of the process, my hands ached and it was terribly boring. Next time I would be sure to be more careful when making the original cuts.
I used a big plastic shop organizer with drawers to sort my parts, so I didn't have to keep remeasuring them to tell the difference between the 3"x2.75" part from the 3"x2.625" part and such. On the right you can see a picture of me working on Christmas morning, gluing up some of the assemblies.
Once the pieces were the correct size, everything glued together quite quickly. It really helped that I kept the pieces well organized for this step. I was careful to lay everything out first before I glued anything up and double checked the plans to make sure I was positioning things right. Fortunately, the gluing did not need to be super-precise, but I did my best.
Once I got all the panels glued up, I put the box together without glueing on the front panel to test it out (as Bruce suggests). When I stepped through the move sequence, it turned out that it was possible to complete the puzzle in fewer than 25 moves, since the left hand panel slid off prematurely. I ran through it a few times, double checked the plans, and confirmed that it was indeed a problem with the plans.
I emailed Bruce about the issue and he discovered that the plans on his site were out of date: somebody else had spotted the problem and he had a solution but it wasn't posted. Fortunately, the solution was very simple: I just needed to glue a stopper block on the left panel to keep it from sliding off and I was back in business!
It took a bit more sanding to get the mechanism working smoothly, but eventually I got it working to my satisfaction and was ready to finish the box. As Bruce suggested, I painted the edges black and printed out the nice orange and brown pattern that he used. I printed it out on glossy paper, cut it out, and then glued it on to the various panels using a spray glue. This may seem horrible to those of you who like to appreciate the grain of the wood, but I was using plywood so there wasn't much to appreciate.
It was tricky to cut the siders free after I glued the pattern over them. My razor kept going askew, so I had to pull them off, re-print the pattern and try again, which was quite frustrating. Eventually I got it right, though and waited for the glue to dry. Finally, I added a few coats of varnish and was ready to glue the box together.
This made me nervous, because once it was glued up I couldn't make any more tweaks to the bottom panel mechanism, but it seemed like everything worked fine so I went for it. After several hours, I tried to open the box and when I got to the bottom panel, it wouldn't budge! All this work and I had ruined it on the last step! I freaked out and pulled on it as hard as I could and eventually in broke free. Whew! That was a close one!
So that is the story of the first box that I made (I say that like I've made a ton since then...I've only made 3 more). It turned out quite well, for a first effort, I think. If I were to do it over again, I think I could get much better tolerances on the cuts by using a micrometer for everything. The end panels ended up a bit loose because they didn't fit snugly against the runners, but everything still works fine.
I had a great time showing it around to family and friends, it is a challenging puzzle but a determined non-puzzler can usually figure it out in 20-30 minutes. My thanks to Bruce for making these wonderful plans available. At the time that I made this box they were free, but now he charges a modest fee of £2 each, which I think is completely reasonable. Some of the simpler plans are still free which is great.
Well, that was a long post, but I hope you enjoyed it! Check out more pictures here. Tomorrow, I will write about another puzzle project I worked on concurrently with this one: Frand's Mind Bender!
I've been collecting mechanical puzzles since 2008. My favorite types of puzzles are puzzle boxes and disassembly puzzles, though I also enjoy interlocking solids, assembly puzzles, and pretty much everything else.
In the interests of full disclosure: I make a small percentage from purchases made through links in my blog to Amazon and Puzzle Master. I figure if I'm sending them traffic, I might as well get a piece of the pie.