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Aruki of 3-sun cube

Today is the last day of February. Compared to usual, the number of puzzle boxes I produced this month might have been lower. Well, February has fewer days, so that could be one reason. In any case, I believe that making puzzle boxes still requires a lot of research and improvement. I want to continue my work without compromise.

Today, I first worked on making the Aruki (moving panels) of 3-sun cube box. As I wrote a few days ago, the aruki for this box starts as a single type when preparing the material, but from there, it is divided into three different shapes. In other words, one type for the top and bottom surfaces and two types for the side surfaces. The shape of this aruki combines elements from two different box sizes: 4-sun and 5-sun puzzle boxes. The overall internal structure is the same as that of the 4-sun size, though I have made the width slightly wider. The size of the "bocchi", the small wooden piece that moves inside the mechanism, follows the 5-sun width. However, instead of making it exactly the same as a 5-sun, I kept the 9mm width of a 5-sun but the 18mm length, which is almost the same as a 4-sun. Since this box has more height, widening this part does not cause any issues. Ideally, I prefer to make the bocchi as large as possible, so I decided to increase its width.

This time, since it is a 27-step puzzle cube, I believe the movement of the mechanism will be very stable. In reality, the movement of the box varies depending on its shape and internal structure. This box has 8.5mm thick aruki panels, which are relatively thick, and a structure height of nearly 8cm. Because of these features, the movement is more stable. Since this is my first attempt, I am not entirely sure how it will turn out, but I believe the results will be good.

In the evening, I opened the mechanism of the 5-sun 27-step puzzle box, which I had finished painting yesterday, to check its movement. This may vary depending on the craftsman, but when I make the top panel (lid panel), I initially attach it a bit tightly. At this stage, I adjust it to an appropriate level of tightness. Since the box is already fully assembled, most parts can no longer be adjusted, but this panel can still be fine-tuned at this stage because it can be completely removed, as shown in the photo. There are no fixed rules for making Himitsu-bako, so I follow this method based on my experience. If the lid is too loose, it might fall off due to the force when the mechanism opens. That’s why I believe it’s best to keep it at an appropriate level of tightness. With this process completed, 32 pieces of 5-sun boxes are now successfully finished.
Have a good weekend!