Tamahagane and blue steel history/legend notes

[refcast]

http://daikudougu.web.fc2.com/no36Forum.html
There's a short story in the translation that says blue steel was developed by Yasuki steel based on Western cannon steel. The webpage also has a kanna museum and Sanjo blacksmithing history with some Iwasaki notes

 

[Barmoley]

Very cool article, but the way I read it blue steel was developed based on bits that were used to cut British cannons so most likely drill bits or maybe bits that cut rifling if rifling on cannons was cut at that time. Most likely drill bits. Drill or cutting bits make more sense since cannon itself is unlikely to be made out of steel that is appropriate for knife blades, very different requirements.

"The model for the blue paper was the blade of a bite that sharpened a British cannon. Nagahiro Nagao, the first generation of Echigo Sanjo, used what was produced as scrap steel from the artillery arsenal and saw it with good results, so he sent it to Dr. Haruto Kudo of Yasuki Steel to make the same steel. .. It is a kind of high-speed steel because it is a bite that sharpens a cannon."

 

[refcast]

Yeah that makes more sense than the cannon itself, or even a cannonball -- i would imagine those would be lower carbon steel with no need to be very hard. I assumed that the cannon or cannonball had to be somewhat hard, so it would require air cooling or oil quenching for such a large size, and those steels would probably have chromium or tungsten too

 

[Barmoley]

Yeah I don't know about cannons, but modern rifle barrels are made out of 4150, 416R and the like. I would imagine it was similar at the time too, if maybe inferior to today. Low carbon, tough steels with added elements to improve wear and corrosion resistance.

 

[refcast]

There were two kanji, "big" and "cannon", so I would imagine artillery then, which is about as big a cannon can get aside from Naval stuff.

-- Oh, and later down in the article, it says the "bite", or cutting tool was used on the inside of the cannon, so it makes sense to be some high speed steel or tungsten steel type thing, and not the cannon.

-- also another blog post of yasuki steel legends / hearsay
http://blog.livedoor.jp/new_alces/archives/4980960.html