Evolution of the Kezurou Contest in Japan

by Karl Bareis, with preface by Andrew Hunter (adapted from The Wooden Post, vol 14, December 2019)


Kezuroukai USA has also taken part in this quest for the perfect shaving. For nearly 20 years Japanese woodworking enthusiasts have been gathering here in America to share, learn and support one another.

These events, which are mainly geared toward introducing a larger public to the wonders of Japanese woodworking, involve our own version of a planing contest. With similar guidelines as those used in Japan, these American competitions are just as exciting. Granted, the shavings here in the States may be a bit thicker than our Japanese mentors, but this only takes some of the pressure off.

The planing competitions put on by Kezuroukai USA are about improving our skills as woodworkers. Competitors are not competing against each other, as much as they are competing against themselves.

There are so many small factors that add up to getting a Kanna to perform at it’s best, and it takes dedication to master these skills. Having a way to gage your progress is very helpful. A thin shaving can tell you everything you need to know about the state of your tool.

A blade that can cut a clean 10 micron shaving has no scratch in its edge deeper than 10 microns. Even the size of the throat opening and the flatness of the sole can all be judged in a shaving.

In the end of course, what matters is the wood’s finished surface; how smooth it is to the touch? How much does it shine? A thin shaving is a way to quantify the surface quality. A clean 10 micron shaving tells us there is no blemish in the wood’s surface deeper than 10 microns. A surface like this will reflect light like a mirror and will withstand the elements far longer than a rougher surface. Most importantly, a cleanly planed board shows the respect a craftsman has for their material and tools
– Andrew Hunter

The Kezurou Contest has undergone few changes since its inception in 1997. But of late as the sheer number of competitors has increased some changes have followed. In Japan during the 2019 competition, there were nine teams of carpenters representing firms that sponsored teams to compete. This sponsorship of teams is nothing new, but the movement towards larger teams of carpenters working under the same corporate entity is something which has emerged relatively recently in Japan. The sponsored teams dress identically and work to create a perfect plank to present during the early rounds. Nowadays people soak their planing planks in water right up to the time they leave for the competition. Once in travel mode they wrap the plank in plastic stretch-film to preserve its moisture and flat surface.

Perfect 12 foot long “stock” planks for sale.

Perfect 12 foot long “stock” planks for sale.

Related to the care and choosing of the perfect wood plank, several wood suppliers have begun to sell highly-selected material at the contest. These are air-dried under perfect conditions and ready to use, except that they are never bought and put into service without being properly prepared by carpenters and tested over months and years. A real competitor invests in several of these perfect 12 foot long “stock” planks, and the suppliers give very precise information, as to where the tree grew, when it was cut, and other information that amounts to a pedigree. The prices for this very select material is extravagant; wood merchants have high-graded it up to where only a few planks are on offer each year. Prices vary greatly—a piece of select Hinoki Cypress, from the national forest on Mt. Ontake—called Bishu-hinoki can fetch over $700 per plank. The fact that the materials are rare makes the price worth paying, and the way these planks are pampered and cared for results in a good board lasting many years.

The Tool

Of course there couldn’t be a contest without tool makers —folks who also understand the demanding level of endurance and perfection needed in order to survive the competition. It could be said that indeed the testing of the tools in this way has in no small degree revolutionized the art of smithing. Modern Kanna planes have incorporated the technologies and chemistries discovered by trial and error. Individual blacksmiths found that they could demand exacting steel specifications from their suppliers. In turn, manufacturers began testing their steel formulas to match the feedback from the toolsmith. Many of the these changes are spurred on by the intense competition begun over the past two decades. Inadvertently this has given toolmakers a standardized testing method to monitor results and see how well their tools hold an edge. This is true of carpenters as well; it used to be true that most carpenters never displayed their skills in public, but now both tool makers and carpenters alike have a way to gage their skills, and find scientific methods to improve how they perform. Last year in an interview, an eighty-six year-old master carpenter from Takamatsu said that at first “successful carpenters didn’t have time to waste on frivolous competitions, but over the years they’ve all come to see how the Kezurou-kai movement in Japan is improving the skill level of both the tool makers and the carpenters”. (SEE planing finals on-line https://www.youtube.com/watch?v=o0v6EnMRsPg)

The Contest – A five micron shaving

This year 96 benches were set up in the Prefectural Gymnasium in Ina Town. The area where the 35th Kezurou Kai took place is a proud center of woodworking skills going back centuries. The gathering brought many first-timers from nearby to try their hands at beating the best in the land. One of their own, Masaru Kamijo, had already been known for his skill and had personally invited many of them.

Because the nature of the event has evolved to include such large turnouts, the methods to test results have evolved as well. Many elaborate systems have been put into place to insure everyone is working on a level playing-field. The contest starts with people bringing their equipment indoors and being assigned to a place, surrounded by other folks —all concentrated on set-up.

By early afternoon the judges have several very thin wood shavings hanging on a rack for all to see. Small clips of paper identifying the person’s name, address, and measured thickness of the shaving. The first level of the contest is determined by the winnowing out of all but the thinnest shavings. At this point in the process the judges are volunteers, armed with micrometers and stretching bars, to assure uniformity.

The Finals

For the final competition a single common plank is used by all contestants. It’s noteworthy to mention that finalists never produce winning shavings anywhere close to the thinnest shaving of the day. This year the winner had a shaving measured at 15 microns; a full ten microns thicker than his water-cured plank produced in the earlier rounds.

Once six or seven of the very best contestants have been identified, they proceed to the main stage for the final round. At this point judges begin to look at more than just the thinnest shaving, they begin to observe a set number of attributes which will eventually dictate who is the contest winner. Judging comprises three distinctions: working within a time limit, width of shaving, thickness of shaving. In addition each contestant must prepare the official contest plank to match his tool, and this is where the efficient use of time is critical.
Most contestants bring three planes into the finals — in order to prepare the surface and make a perfect shaving.

Contestant pulling a shaving during a planing competition

Contestant pulling a shaving during a planing competition

First the contestant steps up to the table, places his tools down and waits for the judge to start the clock. The main judge is seated where he can view the plank and shaving at eye level. Another referee’s job is to pluck the shaving from the back of the plane and hold it up so that everyone can clearly see it, and nothing impedes the process. In Japan this year there was a third judge who was seated at the back of the plank where he could judge the movements of the contestant and confirm the main judge’s results. After several preliminary pulls the contestant is ready to produce a shaving. Once he has pulled the shaving to within a few inches of completion, he stops, steps away from the plane, gets the okay from the judge that his shaving meets the criteria. If the shaving has any anomalies like gaps and thin tatters, it is judged as unworthy. This is important because the thinnest complete shaving is the critical criteria. The contestant is allowed to pull another shaving without penalty, unless the time has run out. So the proper use of allotted time is definitely a major factor and strategy used by finalists.
– Karl Bareis