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

Woods with interlocked grain

Woods with interlocked grain
Today I took things a bit easy while waiting for the materials to dry. The 3-sun cube 14-steps boxes have already finished the painting process, and I plan to do the final check tomorrow. For this year’s three-color checkered pattern, I used a very good part of the Rengas wood, so the red color turned out beautifully. I still have a small stock of rengas wood, but parts with such a bright red color are quite rare — usually, the red is a bit darker.

After that, I continued preparing the top and bottom panels for the 3-sun cube 18-steps natural wood type, as well as the panels for the hexagonal boxes — just like yesterday. Today, I cut the wooden blocks into thin pieces and planed (machine) them to the proper thickness. They’re now stacked and drying. Some people prefer to let the wood dry before planing it to the exact size, but in that case, the wood may warp or shrink later. So this time, I decided to dry it after planing it first. Of course, I’ll sand the panels again at the end, so even if they get a little dirty during drying, it’s no problem.

The panels in the photo are the top and bottom panels for the current 3-sun cube boxes. They are made of Japanese camphor wood (Kusu), combined with rengas and urushi wood, with a thin line of magnolia wood in between. I’m still thinking about where exactly to cut them—I want to make the cuts as symmetrical as possible, but since the cube size is fixed, I’m not sure how it will turn out 😅 From one large panel like this, I can get five panels for the boxes. This time, I plan to make about fourteen of these natural wood type boxes. That’s a bit few for a limited edition, but since I’m making them at the same time as the checkered design type, that’s the number I’ll have.
Kusu wood has what’s called “interlocked grain (cross grain),” which means the grain often crosses and changes direction within a single board. Because of this, some parts can chip when planed with machines, so I was a bit worried about that yesterday. Kusu wood can be a bit difficult to work with. When I planed it today, there were a few tricky spots like that, but it looks manageable. It seems I’ll be able to use these panels as planned.

Another type of wood I have a lot of in stock is Karin wood. This wood also often has interlocked grain, like kusu wood. And since it’s much harder than kusu, I don’t really feel motivated to use it (haha). When carving it with a blade, even a skilled craftsman can easily cause it to chip. Because of that, it might not be the best choice for making thin wooden panels like the ones I use for my boxes. For woods that can’t be easily shaped with blades, I sometimes form them using sandpaper machine instead.
and The other panels I prepared today — the top, bottom, and side panels for the hexagonal boxes — are now finished and laid out to dry. They’ll need to stay that way for a little while longer, so I’ll probably start working on the hexagonal box assembly next week.