Starrett 56973 O1 Tool Steel Flat Stock 0.25x0.75x18 in

Product Description

The STARRETT 56973 is an O1 oil-hardening tool steel flat stock bar measuring 0.25 inches thick, 0.75 inches wide, and 18 inches long. Made from AISI Type O1 tool steel, this flat stock is supplied in the annealed (soft) condition, ready for machining, grinding, and finishing before oil-quench hardening. It is a standard choice for toolmakers, machinists, and die shops fabricating punches, dies, gauges, jigs, fixtures, and other precision tooling components. The controlled tolerances and edge squareness make it suitable for applications where dimensional consistency prior to heat treatment is critical.

This flat stock is used in machine shops, tool and die operations, and maintenance and repair environments where O1 tool steel is specified. Its 18-inch length provides a practical starting blank for a range of small-to-medium tooling projects. The piece weight of approximately 0.96 pounds makes it easy to handle at the bench. Machinists select O1 flat stock when moderate wear resistance, good machinability, and straightforward oil-hardening heat treatment are the priorities. It is not intended for high-speed or high-heat cutting applications.

Key Features

• AISI Type O1 oil-hardening tool steel — machines cleanly in the annealed state and responds well to oil quench hardening
• Thickness tolerance of +0.0100 to +0.0150 inches for consistent stock removal calculations
• Width tolerance of +0.0100 to +0.0150 inches across the 0.75-inch face
• Length tolerance of +0.2500 inches on the 18-inch nominal length
• Edge squareness held to 0.003 inches per inch on all edges
• Single-piece packaging with no minimum order beyond one unit

Compatibility

Designed as a standard O1 oil-hardening tool steel flat stock blank suitable for general toolmaking, die making, and precision machining applications where AISI Type O1 material is specified.

Installation Notes

Machining and grinding of O1 tool steel flat stock should be performed using tooling and speeds appropriate for annealed tool steel. Heat treatment — including hardening and tempering — should be carried out by qualified personnel following established metallurgical procedures for AISI O1 tool steel. Wear appropriate PPE when cutting, grinding, or handling sharp-edged stock. Consult applicable shop safety codes and material safety data when performing heat-treat operations.