Vintage Japanese 70mm kanna.
This kanna blade is stamped down the middle RAI KUNITOSHI, a fictitious name with some reference to samurai lore, and YAMASHIRO an important and ancient region that now includes southern Kyoto prefecture. This local reference most likely indicates that the blade was forged in Miki city. The laminated sub-blade is an associated later blade and is marked TOKUSEI or specially made.
The traditional laminated kanna main blade has been tapped out, ura-dashi and flattened, ura-oshi by me and in doing so I found the jigane soft iron backing to be very malleable and easy to work with displays of subtle folding patterns and antique wrought iron characteristics associated with kamaji or antique boiler plate or bridge iron which is expensive and a finite material. The main and sub blades have been fitted to each other.
There is a small patch of old rust on the main blade that has been polished out and you can see it in the photos on the lower left edge. This patch is out of the cutting area and was a result of keeping the blade stored while inserted into the wooden dai over a period of time. I have drawn a line with ink on the blade for the photo as it sat in the dai to show the active cutting area. This type of oxidation is somewhat common and it does not affect the cutting qualities of the blade because as you can see it is off to the side.
This kanna is new/old stock and the main blade was hand forged in the traditional manner in the late 1940's or most likely in the1950's using kamaji soft iron as the jigane or backing iron and traditional white or blue high carbon tool steel for the cutting edge.
I do not know and will probably never know who the actual blacksmith was, but this kanna was made for the Japanese professional woodworkers market, not for export. In Japan up until the 1970's, general handymen or homeowners did not normally buy specialized 70mm finishing planes of this quality. They were expensive, required training to maintain and would not likely be used often enough . This is an example of NEW/OLD stock that has not been used but has instead just been languishing as dead storage since the 1960s in a closed up store in rural Japan until I brought it to the U.S.along with many others about four years ago.
The white oak dai is marked with a ink stamp that reads it was oil treated. I have freshly surfaced the top and sides of the dai while retaining that ink stamp, and have flattened the sole and have partially fitted the main blade down the blade chute hand tight to
within 1.5cm of the sole and mallet tight to within 7mm of the sole. This is a dense and beautiful high class oimasame or quarter sawn grain pattern dai with the blade mortise set up with the tsutsumi-guchi ledge to support the blade bevel when the plane is set up in the cutting position. The tsutsumi feature is found in better dai and requires extra steps in the making. This style provides a very narrow mouth at the sole of about 3.5mm wide, necessary for really close finish planing.