Kannaba Japanese Smoothing Plane Blade By Keizaburo - 55mm・Tamahagane

Blade Weight: 225g

Blade Angles: 25°

Chip Breaker Width: 49mm 

Accessories: Chip Breaker

Additional Information: Unused, brand new condition. The mark stamped on the front of the plane blade is ”圭之助“(Keinosuke).

Regarding the tamahagane used for the blade, I will attach a copy of the handwritten instructions from the blacksmith, Keizaburo. Below, I will briefly outline the contents of this document.

According to the document, when Keizaburo acquired this steel, he did not know it was tamahagane. He only knew it was the steel used by the Miyano smithy to make tools such as kiridashi  and sen. Its composition is similar to modern carbon steels (such as White Steel No. 1 and Swedish K120), but it also contains trace amounts of elements typically found only in special alloy steels (Cr, W, Mo, V, etc.). When he performed a spark test on this steel, it produced highly unusual sparks. Unable to find anything similar in his entire steel collection, he speculated that it was a pre-WWII steel. The steel itself had the words "硬" (Hard), "硬鋼" (Hard Steel), and "ヨウカイ" (Yokai) written on it. (This is why Keizaburo stamped a "K" on the back of the plane blade, as the word for "硬" is pronounced "Katai" in Japanese.)"

To uncover the true nature of this steel, Keizaburo went directly to the third-generation blacksmith, Miyano Tetsunosuke, to inquire about it. The third-generation Miyano informed him that this was a steel created by Miyano Tetsunosuke Ⅰ or Ⅱ by melting down traditional Japanese tamahagane (the word for  'melting' is written in katakana as 'ヨウカイ').  Regarding why tamahagane, which is essentially a pure carbon steel, would contain trace elements typically found only in special alloy steels, the document explains: 'By melting down the tamahagane and mixing in special elements to the base, this is by no means impossible.

In my own understanding, because Miyano Tetsunosuke was born into a lineage of Japanese swordsmiths, mastering a highly difficult material like tamahagane would have been second nature to him. Therefore, it is not hard to see how he was able to use it to create this truly unique “Yokai tamahagane”.