The rain that continued until yesterday has stopped, and it has been cloudy since this morning. Because of the cloudy sky, it feels colder, but compared to last week, the temperature is not so low. From this morning, I worked on finishing the 5-sun puzzle box. I was able to complete it safely by the end of the morning, and now I can move on to the painting process. After that, I continued working on the drawers that fit inside this 5-sun box. There was a small mistake, and I did not have enough drawer lids, so I needed to make a few more. Fortunately, I still had some materials left, so I was able to finish without any problem. The drawers only need to be completed by the time the 5-sun box is finished, so I still have one or two days of extra time.
As I wrote yesterday, I have also started working on the next project, which is 4-sun 27-steps puzzle boxes. Yesterday, I attached the yosegi sheets for the side panels, and today I made only the shaft panels for these boxes. If the shaft panels are made according to the correct measurements, they do not need to be adjusted directly to the other parts. Because of that, I sometimes make them in advance like this. This time, I plan to make about 70 boxes, which is a slightly larger quantity, so I think I will continue dividing the production process into separate steps like this.For example, when I have some extra time, I make some of the parts in advance, something like that.
Since last year, I have made the shaft panels slightly thicker. Until now, I made them 8.5 mm thick, but I changed them to 9 mm. It is only 0.5 mm, but I feel that it makes quite a difference. One thing I always think about when making this box is its strength. In the past, this box has come apart a few times because of strong impact. The 18-steps and 21-steps puzzle boxes have a similar structure, but for some reason, the 27-steps puzzle boxes were the ones that had this problem. I do not know the exact reason, but it may be because the upper and lower length of the shaft panels is shorter than in the other boxes. Because of that, the surface area that is glued to the side panels is smaller, and when a strong impact is applied, it may not have been able to withstand it. So, since the upper and lower length is shorter, I decided to increase the thickness to make the glued surface area larger. Since making this change, this problem has not happened so far. Compared to the 18-steps and 21-steps puzzle boxes, the upper and lower length (shaft panels) is 4 mm shorter. That is quite a big difference. In puzzle boxes with 18 steps or more, the bottom panel also moves, so the box cannot be fixed by the bottom panel. The structure of the box is supported only by the four glued areas between the side panels and the shaft panels. Because of that, I am trying different ways to make the box stronger, such as increasing the thickness like this and improving how I apply the glue.
