In 2019 we had the pleasure of hosting 25 students in Melbourne and Brisbane to make kanna under the tutelage of Kyoto carpenter Takami Kawai-sensei. In these classes, we supplied 70mm Yamamoto blades got to see all of them set up (backs lapped flat and sharpened to #8000 grit) and used to make completed planes. This experience, as well as our own experiments in building and sharpening our own planes with Yamamoto blades, convinced us (truly, madly, deeply) of the quality of these blades - as if their maker's reputation wasn't enough.
These planes utilise Yamamoto's same hand-forged blue paper steel (aogami #1) blade sets that we used in those classes. The blocks that they are set in are impressive for their beautifully selected grain and the implementation of a tsutsumi. The tsutsumi is an extra facet of the blade bed that matches and supports the bevel of the blade. It is designed to minimise vibration by adding supporting timber much closer behind the cutting edge than would otherwise be possible. The tsutsumi will require the craftsperson to pay extra attention to the sole underneath the blade, and also adds another element to monitor while setting and tuning the blade's bedding.
The mouth on the Tesshinsai planes will be extremely tight.
Furthermore, the sole of these planes is not relieved behind the mouth. This gives the user complete control over how the contact patches of the plane are set up, and what tolerances are deemed acceptable in the sole conditioning.
For these reasons, this plane is not recommended as a first tuning experience. For those who have tuned a kanna before, patience and care in the tuning of this block will reveal a plane capable of beautiful results.
Block Length: 285mm
Block Width: 83mm
Block Height: 35mm
Blade Length: 115mm
Cutting Edge Width: 56mm
Blade Angle: 38 degrees
Tsutsumi Depth: 7mm