Book Review: Shoji and Kumiko Design Book 1 The Basics

Des King is an Australian who, after a career as a translator of Japanese, decided upon a change of direction in life and enrolled in a woodworking school in Japan in 2008. After 12 months of intensive study at the International College of Craft and Art (Shokugei Gakuin) in Toyama, Japan, Des returned to Australia and established a workshop on the portion of southern Queensland known as the Gold Coast.  There he specializes in making shōji, focusing his attention particularly on the design and execution of kumiko. Kumiko, 組子, literally joined (組) children (子) – an oblique reference to things that are part of a larger squad – are the lattice bars which form a core decorative element in Japanese screens and can be developed in a wide variety of direction and to great complexity, as this example shows:

Des wrote a couple of articles on shōji making for the Australian Wood Review, and that spurred further writing on the topic, which has resulted on the first of what is planned to be a series of volumes, Shoji and Kumiko Design Book 1 The Basics:

I snapped this book up when I first came across it several months ago, as I am always hungry for more knowledge on Japanese woodworking and was interested to see a westerner’s take on a Japanese art. The book did not disappoint.

There are few resources in English on the subject, the only two coming immediately to mind are Jay Van Arsdale’s book Shoji How To Design Build and Install Japanese Screens, and Toshio Odate’s 2000 publication entitled Making Shoji. 

While Odate’s book provides an overview of the construction of one standard akarishōji, it is as much about the cultural background and attitudes of shokunin and the author’s experiences learning the trade in Japan as a young man. King’s book however is much more specific and technical in regards to shōji, which pleased me immensely. 

The book begins with an overview of Japanese planes, and the variety of types, along with their set up, blade sharpening, and maintenance. I think for those who are struggling with their Japanese planes, Part I of the book provides a tremendous amount of invaluable information. While the section on sharpening contains mostly broad generalities – which is really all that is possible, given that sharpening approach varies with the tool and is mostly a matter of practice – I found the section on tapping out particularly well described. 

Tapping out, or ura-dashi, is a process done with Japanese planes blades to maintain a specific shape of hollow (ura-suki) on the backside. Repeated sharpening brings the cutting edge progressively closer to the hollow, creating a very thin lead edge (uragire) on the cutter and sooner or later the hollow must be re-established. King explains the situation quite succinctly:

Why do we have to tap out? If it’s such a risky procedure why don’t we just keep flattening the back until the uraba is broad enough so we don’t need to tap out?

A broad uraba, and wide ashi to the sides of the urasuki is certainly an ugly sight to see, but it goes well beyond the aesthetics…The urasuki in the ura helps to stabilize the blade on the finishing stone by reducing the overall area of contact, and this in turn makes it easier to achieve good contact between the blade edge and the stone and to remove the burr for a sharp cutting edge. The narrower the flat area to the front and sides of the urasuki, the more efficient this polishing and burr removal is, and the easier it is to keep the back perfectly flat.

If we fail to tap out when our sharpening has brought us to the uragire condition, or we don’t tap out properly or sufficiently, we’re creating two problems, one of which is very serious indeed.

If we don’t tap out or don’t tap out enough, we need to remove a substantial amount of very hard metal from the two ashi to form a reasonable uraba again that we can polish and keep flat…

…Kanna blades are wedge-shaped, and it’s this wedge shape that seats the blade firmly in the dai…if we were to remove the necessary amount of material from the sides to recreate the uraba from an uragire condition without tapping out, and repeated this several times, we would have radically altered the thickness of the blade and therefore the geometry of the wedge. The blade would be extremely loose in the dai and the cutting edge would simply drop through the mouth.

Des goes on to explain tapping out in more detail over the next dozen pages, giving a picture-by-picture analysis of common mistakes in tapping out, readily analyzed by looking at the shape of the uraba. I think this was an excellent section that will undoubtedly prove valuable to any Japanese plane user, whether they make shōji or not. Just as the shaving gives most if not all of the clues one needs to determine what is going on with the plane, the shape of the back of the blade tells you what has been happening with tap out. A guide such as King provides will be of great service to many woodworkers I do believe.

In an upcoming Part II of this book review, I’ll take a look at the remainder of the text, dealing with shōji history and the construction of three basic types of shōji. I hope you’ll tune back in then and thanks for visiting the Carpentry Way. Comments always welcome.  On to Part II ← (link)