I had heard of Kezurou-Kai USA November last year after they published photos of their event and signed up immediately for this years event. I think Kezourou-Kai translates to “let’s plane wood” and is an annual festival of temple builders. Apart from planing we had workshops on how to make Japanese mallets and sharpening stone holders. We also had demonstrations on how to make shoji screens, how to layout fan rafters on your bell tower roof and how to construct temple column brackets. Hiroshi Sakaguchi showed us how to fit the base of your bell tower post to its round foundation stone with a yari ganna spear plane and presumably the more modern technique of using all thread to tie your post to its concrete foundation pad. All useful stuff if you building a temple.
We watched demonstrations on how to tap out and sharpen the thick Japanese blade. How under cut the plane sole. How to set the blade and use the plane. Apart from learning heaps I also had the opportunity to plane some American timber. The timber of choice for the competition was Port Orford Cedar which an incredibly clear and finely grained soft wood. The tuned Japanese planes were producing close to mirror smooth finishes on the timber.
The Japanese plane iron is a very thick piece of soft steel with a thin layer of hard steel forge welded on the front face. Tapping out or ura dashi involves peening the soft part of the edge to bend the hard layer so that you can lap the edge without grinding away all the hard steel. If you’re planing wide beams you need a wide plane and if you’re trying to keep it sharp tapping out will speed up the process.
No glue, nails, screws or bolts. The column brackets simply stack together like lego held together by the weight of the roof. In an earthquake the post flexes and the bracket blocks separate whilst the weight of the roof provides constant clamping pressure without overloading the components.