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Side panels

Yesterday was a very rainy day, but today it cleared up starting in the morning. However, the day after heavy rain is often quite humid, and today was no exception. According to my work schedule, I was planning to attach the side panels of 3-sun and Mame puzzle boxes, but due to the humidity, I decided to only prepare for the gluing process in the morning for now.

In other words, I prepared the panels for each box and processed them so they’re ready for gluing. For the 3-sun 12-step puzzle boxes, the long side panels are attached next. To do this, I first cut off the parts of the already attached top and bottom panels that stick out, making the sides flat. The cutting dimensions here are very important — the cut must match the position of the structural side panels exactly. If it’s cut too short, a gap will appear between the lid and the side of the box. If it’s too long, the outer panel can’t be attached properly, and if I force it, the lid will be pushed down too tightly and won’t move smoothly. So I carefully adjust the length to find the perfect fit (photo).

This time, I’m making two types using solid wood too. For the version where all the outer panels are made of walnut, I used solid walnut boards for the top and bottom panels instead of the usual sliced walnut veneer attached to plywood. This wasn’t a special order — it simply worked out that way due to the materials I had available. As for the natural wood type that uses several kinds of wood, I used four different types for the top and bottom panels. This particular wood arrangement and design has been in use since last year.

This time, I’m working on the 3-sun size boxes, but recently I haven’t made the 4-sun version using walnut for the side panels. It’s quite difficult to manage, and sometimes after production, the side panels begin to warp. One of the weaknesses of puzzle box construction is the thinness of the structural materials. Depending on the craftsman, the outer side panels are usually only about 4 mm thick. So when making a 4-sun size box, the panels are slightly larger, and unless the wood is very carefully selected, there’s a risk that the side panels will warp outward after being attached. With 3-sun size boxes, this almost never happens. Even though I use various techniques to prevent warping, things don’t always go as planned. That’s why I tend to make the 4-sun versions using yosegi sheet (include ichimatsu design) designs instead. Of course, I still make them upon request 😄

In the evening, the humidity dropped and the conditions improved, so I went ahead with attaching the panels for the 3-sun boxes. As for the Mame himitsu-bako, there are two types and a larger quantity to handle, so I decided to do those starting tomorrow.