Kobaya is a term for a type of smaller military style vessel that is fast and maneuverable. Highly ornate versions of these and larger military vessels called sekibune were used by daimyo and their clans for ceremonial and other official purposes. I don’t know about the smaller ones, but the larger ones were called gozabune. In my limited experience, smaller gozabune are often referred to by their military name, kobayabune or simply kobaya, which means “small and fast.”

Photo of a 30-oar kobaya, of small fast-boat, from a display of models built by Yukio Nakayama. Photo is courtesy of The Rope.

Ship modelers building American or European subjects are accustomed to finding detailed drawingsfor the more popular of these vessels. There are even large numbers of plans made specifically for ship modelers. But, unlike with western subjects, there is a dearth of plans of Japanese watercraft. I’ve found plenty of sketches and there are basic line drawings that might be used, but these commonly don’t have the information needed to build a proper model.

One reason for this is that Japanese boatbuilders don’t have a tradition of recording their work, and they generally only make temporary drawings on wood, sometimes destroying them when done.

Japanese boatbuilder’s plank drawings. Photo courtesy of Douglas Brooks.

American boatbuilder Douglas Brooks, while studying traditional Japanese boatbuilding, has collected measurements and information to create plans of his research subjects, but the cost to him for doing all this work in Japan makes his plans too expensive for most ship modelers. I’ve been in discussions with him about making something available for model builders that I can share here, or that he might sell directly. That may eventually happen, but here were talking about currently or recently constructed small boats.

But, what about the larger, older vessels, like bezaisen, gozabune and the kobaya?

As it turns out, there is one source of drawings that is readily available, based on measurements taken by French Lieutenant de Vasseau (First Lieutenant) Armand Paris. The drawings are available in a collection of books by retired French Admiral Paris (different Paris) called Le Souvenirs de Marine, originally published in 1882, I believe. The books have seen multiple reprints, and are readily available through maritime and other libraries. Old copies can even be found on used book sites, like Abe Books, but it’s a bit expensive. A simple paperback collection of selected plates is available on Amazon, and copies can be found in better library collections.

I wrote about this in detail in an earlier blog post which you can find here.

One of the subjects in the book is a called a Petit Galere or small galley. In this case, they are referring to a kobaya, and there are several views and cross sections shown, and are the types of drawings that one would expect of a western-style ship,

Scan courtesy of the San Francisco Maritime Research Center. Note the distortion on the left is due to limitation of scanning a bound copy of the plans.

The biggest issue I find is that these are western-style drawings of non-western watercraft. These kinds of drawings work very well for the kinds of subjects that ship modelers are accustomed to making, usually planked hulls built over a framework of bulkheads or a solid hull. So, the plan views that are normally most helpful are the standards of western naval architecture, like the body plan, sheer plan, and half breadth plan. These drawings help us identify the shape of the hull at various station lines, and we can determine the shape of the frames needed to build a fair hull.

Japanese boats, certainly the smaller ones, are built with generally only four stations of known measure. Thick planks are bent to match these few points. Because planking on Japanese watercraft is thick, it’s harder to bend, which is one reason why most of the simpler looking Japanese boats tend to have the same nice, natural curved shape. The planks are also wide, and Japanese boats commonly have a chine hull with something of a 5-sided hull shape: A bottom, and what might be termed garboard planks and sheer planks.

The large collection of traditional Japanese boats at the Toba Seafolk Museum

Ideally, we want measurements at the critical station lines, which are not necessary those given in the place, and much information has to be derived from the drawings. But, at least the information is there, as long as you know how to get at it and know what you really need.

So, it is certainly possible to build the kobaya from the Paris plans. After all, it’s been done before, as there are models in the French national maritime museum based on them. But it may take a little extra work, and to build one properly takes a little understanding about the basic design of Japanese boats.

This will be the a subject of what will probably be my next wasen model.