O-1, or oil hardening type 1, is a tool steel that has a place in many industries, including and particularly knife making.

NJSB O-1 is hot rolled with the option to run your pieces through the grinder to remove any decarb.

Easy to forge and grind, O-1 is a great steel for many applications among seasoned makers with the ability to accurately heat treat it. O-1 does require specific temperatures and soak times so it may not be an optimum choice for inexperienced novice makers with limited equipment.

As a deep hardening, high carbon tool steel, O-1 is hard to beat, literally.

From beasty competitions choppers to elegant high-speed kitchen cutlery, NJSB O-1 is the go-to tool steel for any major application you can consider.


Find our Suggested O-1 Heat Treat Here.

Listed below are our current LIVE and the most recently CLOSED material lot certifications per thickness:

  • O-1 .070 (1/16”)

    Previous: N/A

    Current: N/A

  • O-1 .094 (3/32”)

    Previous: N/A

    Current: 23753

  • O-1 .125 (1/8”)

    Previous: N/A

    Current: 23753

  • O-1 .156 (5/32”)

    Previous: 23753

    Current: Zl05986

  • O-1 .187 (3/16”)

    Previous: 23753

    Current: Z111770

  • O-1 .250 (1/4”)

    Previous: 23753

    Current: 2105986

Additional information

Weight N/A
Dimensions N/A


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