Steel Heat Colors

Shop chart · knife steel

Slide the heat. The bar shows the color you would see on the steel, and the line below says what that heat does to a blade.

1475°F

802 °C

Bright cherry

Glow, seen in a dim shop

Temper Magnet Harden Forge Weld

Hardening heat

Common shop values for simple high carbon steel such as 1084. Your steel's own data sheet wins. Below 700°F the color is the thin oxide film on polished steel; above about 900°F it is the glow itself.

Edge Calculator

Shop chart · knife edge

16° per side

32° included

Japanese-style knife

Booklet chart

Shoulder 10.70mmthick

Height1.22mmabove the edge

Main grind2.0°per side

Behind edge0.57mm1 mm up

Spine lift0.55inon the stone

Steel left60%of the bar

Edge angleper side

Japanese Hunting Mower Axe

Stock thickness Blade height Grind height Edge before sharpening

Calculated in true scale from straight faces. Not a strength test. Examples are from Alessio and the AZCK sharpening booklet.