Starrett 56975 O1 Tool Steel Flat Stock 0.25x1.25x18 in

Product Description

The STARRETT 56975 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die-making, and precision machining applications. Manufactured to AISI Type O1 specifications, this flat stock measures 0.25 inches thick, 1.25 inches wide, and 18 inches long and weighs 1.59 pounds. Thickness and width tolerances run from +0.010 to +0.015 inches, and edge squareness is held to 0.003 inches per inch. O1 tool steel offers good machinability in the annealed state and responds well to oil-quench hardening, making it a reliable choice for custom tooling, punches, gauges, and fixtures that require a hardened and ground finish.

This flat stock is suited for job shops, tool rooms, and maintenance departments where small quantities of precision-ground tool steel are needed for one-off or short-run tooling. The 18-inch length allows for multiple blanks to be cut from a single bar. It is appropriate for applications in metalworking, moldmaking, and general industrial fabrication where close dimensional tolerances are required before heat treatment. It ships in a single-piece quantity and has a minimum order quantity of one bar.

Key Features

• AISI Type O1 oil-hardening tool steel for reliable, consistent heat treatment response
• Thickness and width held to +0.010 to +0.015 inches for close-tolerance blanking
• Edge squareness of 0.003 inches per inch across all edges
• Length tolerance of +0.25 inches ensures usable full-length material
• Single-piece packaging suits low-volume toolroom and maintenance needs

Compatibility

Designed as a standard AISI O1 oil-hardening tool steel flat stock suitable for general toolmaking, die-making, and precision fixture fabrication applications requiring a prehardened or anneal-and-harden workflow.

Installation Notes

Cutting and machining should be performed in the annealed state prior to heat treatment. Oil-hardening tool steel requires appropriate personal protective equipment and proper ventilation when grinding or machining. Heat treatment, including hardening and tempering, should be performed by qualified personnel following established metallurgical procedures for AISI O1 tool steel. Allow the bar to reach ambient temperature before taking final measurements against specified tolerances.