The Heat
Proper blade selection begins—and ultimately depends—on its intended use. Hunting, cooking, self‑defense, or display pieces each demand very different categories of steel.
Every steel type must be annealed, hardened, stress‑relieved, and tempered to precise parameters to prevent cracking, chipping, or catastrophic failure.
When the steel is matched correctly to its purpose and treated with the proper heat‑treat regimen, the result is a blade that performs reliably and endures.
All heat‑treating in my studio is performed in a precision‑controlled Paragon kiln. This ensures accurate temperatures, consistent soak times, and the ability to tailor the steel’s properties with intention. Open‑forge heat treating can vary widely, making it unsuitable for the level of consistency required in high‑quality blades.
The Quench
The quench is the defining moment in blade creation. Oil is most often used, with water reserved for specific steels. Proper temperature, viscosity, and timing ensure the steel hardens correctly, forming a dense, durable structure. With mastery, this step turns raw steel into a lasting legacy.
Steel Sample Data
Aogami #2 (San Mai) Blue Paper
Chemical composition
Carbon 1.05 -1.15
Silicon 0.10 – 0.20
Manganese 0.20 – 0.30
Chromium 0.20 – 0.50
Tungsten 1.00 – 1.50
Others P:<=0.025 and S:<=0.004
Standard Heat Treatment temperature (C)
Annealing 750 – 780 Slow cooling
Quenching 780 – 830 Oil cooling
Tempering 160 – 230 Air-cooling
Delivery hardness ( HB ) 229 or under
Hardening hardness ( HRC ) 60 over
Aogami #2.
Blue Paper Steel is one of the greatest Japanese Carbon Steels. Ao [blue] + Gami [paper]
Blue Paper steel is an alloy steel made of White Steel, (a carbon steel with low content of impurities), mixed with tungsten and chromium. Blue Paper steel holds its edge longer than a white steel knife. The features of Blue Steel are excellent cutting performance, retains maximum sharpness and is easy to sharpen.
A fairly reactive steel that requires care in order to avoid rust for it has virtually no rust resistance. An oil coating should be applied and never store this steel in a leather scabbard.