Starrett 54458 O1 Tool Steel Flat Stock 9/16x1-1/4x36in

Product Description

The STARRETT 54458 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die work, and precision machining applications. Manufactured to AISI Type O1 material specification, this flat stock measures 9/16 inches thick, 1-1/4 inches wide, and 36 inches long, and weighs 7.17 pounds. O1 tool steel is a low-alloy oil-hardening grade known for good dimensional stability during heat treatment, making it a reliable choice for cutting tools, gauges, punches, and dies. Thickness tolerance is held to plus or minus 0.001 inches, supporting close-tolerance work before and after machining.

This flat stock is suited for job shops, tool-and-die operations, and maintenance machining environments where consistent stock dimensions are required. Machinists and tool makers use O1 flat stock as a starting blank for custom tooling, fixture components, wear plates, and similar precision parts. The 36-inch length provides practical stock for multiple blanks from a single piece. It is sold as a single bar and is appropriate for both small-shop use and production toolrooms requiring a standard off-the-shelf material supply.

Key Features

• AISI Type O1 oil-hardening tool steel construction for predictable hardening response
• Thickness tolerance of plus or minus 0.001 inches for close-tolerance stock removal
• Width tolerance of 0.000 to minus 0.005 inches for consistent fit in precision setups
• Length tolerance of plus 0.015 inches with no negative allowance
• Squareness held to 0.003 inches per inch on all edges
• 36-inch length provides practical blank stock for multiple workpieces

Compatibility

Designed as a standard O1 oil-hardening tool steel flat bar for general toolmaking, die making, and precision machining applications where AISI Type O1 material specification is required.

Installation Notes

Cutting and machining of tool steel flat stock should be performed by qualified machinists using appropriate cutting tools rated for tool steel hardness. Material should be handled and stored to prevent edge nicks or surface damage that could affect tolerance integrity. Heat treatment, including oil hardening, should be performed according to accepted metallurgical procedures for AISI O1 steel and carried out by qualified personnel. Always verify final dimensions after rough machining and before hardening, as dimensional changes occur during the heat treat process.