Starrett 54080 O1 Tool Steel Flat Stock 1/4x4x18 in

Product Description

The STARRETT 54080 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die making, punch fabrication, and precision machining applications. Made from AISI Type O1 tool steel, it measures 0.25 inches thick, 4 inches wide, and 18 inches long. Thickness and squareness tolerances are held to plus or minus 0.001 inches, making it suitable for applications where dimensional consistency matters before hardening. Width tolerance runs from 0 to minus 0.005 inches, and length tolerance is plus 0.25 inches, minus 0 inches. The bar weighs approximately 5.1 pounds and is supplied in an annealed condition ready for machining and subsequent oil-quench heat treatment.

This flat stock is used in job shops, tool and die operations, and maintenance repair environments where a machineable, hardenable steel blank is needed. Typical applications include jig components, fixture plates, gauges, punches, forming dies, and cutting tools. It is appropriate for both light and moderate stock-removal operations prior to hardening. Machinists and toolmakers working in production or prototype environments will find the close thickness tolerance useful for minimizing secondary grinding operations.

Key Features

• AISI Type O1 oil-hardening tool steel — machines in annealed state, hardens with oil quench
• Thickness tolerance of plus or minus 0.001 inches for consistent fit in precision assemblies
• Width tolerance of 0 to minus 0.005 inches
• Length tolerance of plus 0.25 inches, minus 0 inches
• Squareness held to 0.003 inches per inch on all edges
• Supplied as a single flat bar ready for layout, machining, and heat treatment

Compatibility

Designed as a general-purpose O1 tool steel flat stock blank suitable for toolmaking, die making, and precision machining applications requiring an oil-hardening grade steel in the 0.25 inch by 4 inch by 18 inch size.

Installation Notes

Machining of O1 tool steel flat stock should be performed by qualified machinists or toolmakers familiar with tool steel processing. The bar is supplied in the annealed condition and must be heat treated by a qualified heat treater following oil-quench hardening procedures appropriate for AISI O1 before use in hardened tooling applications. Handle with care to avoid surface damage that could affect tolerance or heat treat results. Always wear appropriate PPE when cutting, grinding, or machining tool steel stock.