Welcome! This is the official online shop of Hiroyuki Oka, a craftsman specializing in traditional Japanese puzzle boxes (Himitsu-Bako).

Balancing Axis Panel Size

Balancing Axis Panel Size
The rain that started yesterday continued today. It gradually stopped, but the humidity remained high. Since it was too humid, I paused production for a while and worked on packing instead. In the afternoon, I began preparing for my next project, the Mame puzzle boxes. Today, I worked on the frames and prepared the materials.

This time, I am making Mame 14-steps puzzle boxes. There was a period when I stopped making this model, but after receiving many requests, I decided to make it again. During that break, I developed the Mame 10-steps puzzle box. It was not meant to replace the 14-steps model, but rather to offer the next step up from the 4-steps model. After that, I made the 18-steps version. I also made a 22-steps version for a while, but its mechanism has very fine parts and is not suited to making large batches, so I have put its production on hold for now. I have a surprising story about this 22-steps model. An old friend from my school days once visited my workshop, and I gave them one of these boxes. Later, while traveling in Hawaii, my friend visited someone who lived there—and found one of my Mame 22-steps puzzle boxes in their home! That person had bought it from me online. Thank you! My friend noticed my maker’s mark inside the box and was so surprised that they contacted me. What an amazing coincidence! Perhaps it means I have made quite a lot of them!..haha. It made me very happy.

Today, I prepared the axis panels as well as the long side panels for these Mame puzzle boxes. I use exactly the same axis panels for the 10-steps and 14-steps models. This is because their Aruki panels and long side panels have the same dimensions, so the grooves for the Aruki panels are also in the same positions. The axis panels fit between the upper and lower grooves, which means their dimensions are the same too. Since Mame puzzle boxes are so small, strength is an important concern. I want to keep the gluing area of the axis panels as large as possible to make the boxes strong. I currently make these panels 5 mm thick. The Mame puzzle box I used as a reference about 25 years ago had 4.3 mm thick axis panels. I followed that measurement for many years before increasing the thickness to 5 mm for greater strength. Recently, however, I have been thinking about making them slightly thinner—perhaps 4.8 mm instead of 5 mm. Many customers want to put something inside these boxes, so even a little extra space would be useful. To keep a large gluing area, I make the axis panels as tall as possible, leaving only about 0.5 mm before they reach the grooves. This means I need to be careful about glue squeezing out during assembly. If it reaches the grooves, it can interfere with the movement of the Aruki panels. I want to use enough glue for a strong bond, but finding the right amount without letting it squeeze into the grooves is difficult.