Isobune means, simply, "inshore boat" and this type is by far the most common fishing boat along the Sanriku coast of Tohoku in northern Japan. They are sometimes called kakkobune or kakkosen; there is some debate about the meaning of the term "kakko".

We were mostly observers of Murakami's work, though he let us do some odd jobs here and there on the boat. Mostly, we performed the classic beginner apprentice work of keeping the shop clean and fetching tools and materials. Documenting his work was a challenge because he offered little explanation of what he was doing (and did not welcome conversation in the shop) and he worked entirely from memory. It turns out he had various angles recorded on the beams of his shop, in affect the written record of his boats, albeit marks only he understood.

Isobune have a very basic shape, with a flat bottom curved upwards aft and depressed slightly at the bow. The rub rail notches into the planking which brings its outer edge flush to the stem, similar to the gain in lapstrake planking. These boats are the only ones I've seen in Japan with this detail. Murakami learned from his father, and the two built boats together for many years, about one hundred isobune in all. The economics of boatbuilding were harsh so they refined their techniques to build these boats as efficiently as possible. They developed a false stem construction to avoid cutting a stem rabbet and they introduced power tools into the process in some innovative ways. For instance, rather than fit planks with a handsaw, Murakami simply runs his circular saw down the seam. He also relies much more heavily on kigoroshi — pounding the plank edges — than any other boatbuilder I have met. This too is a quick way to ensure the plank seams close tightly.

In the spring of 2016 I was invited by the Takenaka Carpentry Tools Museum in Kobe, Japan to build a traditional boat as part of an exhibition on Japanese boatbuilding. I chose the isobune because I felt the destruction of this culture by the 2011 tsunami had national significance, and was relevant for all Japanese. For six weeks I worked in a temporary shop in the museum. I also taught four workshops on boatbuilding, one of which included a public session on yakimage, bending the bottom plank over an open fire. The Museum and I invited Murakami to visit us and help conduct the plank-bending workshop. Our launching in Kobe harbor was Shinto ceremony and attended by several hundred people. The finished boat was donated to the National Museum of Ethnology—called Minpaku—in Osaka.

Read more about this exhibition at the Takenaka Museum page under Japanese Boats at this site.