12 December 2014

Wooden planes - Japanese

A late seventh post in a series about western wooden planes

Thanks to the possibilities offered by ebay I unexpectedly added a Japanese plane to my collection.  The plane was described as 1940's Japanese Old Wood Plane Tool Carpentry. It was offered at a very good price and after a two month wait,  I finally got it home. No complaints about the quality,  no notable bedding problems, no cracks, the only special part is the blade geometry.  Where I expected to see flat surfaces,  I found a lot of curves.  First a secondary bevel just on the lamination,  making it difficult to see if it really is a laminated blade (it is) or a cheaper massive model.
But there was also a curved primary bevel. It will take a number of iterations to straighten the blade and to improve my sharpening technique.  A great help is the youtube series by Sumokun about Japanese planes,  and the faint memory of a Japanese carpentry session.

The not so flat bevels made me think about cupped sharpening stones.  That's not what I expect from todays Japanese blades, but fifty years ago thing could have been different.  Paul Sellers presented today a first post about past cupped sharpening stones.
The same could have been the case in Japan.  In a video 17th Generation Yoshimoto Bladesmith Murray Carter works fluently with a cupped natural stone and expresses his unwillingness to waste stone by just flattening it. He seems to favor controlled wear to get stones flat.

Back to the plane,  with three parts a wooden body and two blades it is a most simple plane.  Setting it up a new plane is probably less simple as every part needs a perfect fit.  The blade for example is wedge shaped in width and thickness.  An extra problem is the width of the blade,  it is certainly impressively wide but it makes everything more difficult to handle. It is a lot wider than my 5 cm stones (2") and also probably than most sharpening jigs.  So if bought  new I would have taken a narrow model. In the meantime I still need a few sharpening sessions to get the blade right and some patience to see how the plane sole stabilizes to the local humidity.