Starrett 54578 A2 Tool Steel Air-hardening Flat Stock

Product Description

The STARRETT 54578 is an A2 air-hardening tool steel flat stock bar used in toolmaking, die work, jig fabrication, and precision machining applications. Measuring 0.25 inches thick by 1.25 inches wide by 36 inches long and weighing 3.66 pounds, this bar is machined and ground to close tolerances before hardening. The AISI A2 grade offers good dimensional stability during heat treatment and solid wear resistance after hardening, making it a reliable choice for punches, dies, gauges, and other tool steel components. Machinists, tool and die makers, and industrial maintenance professionals work with this material regularly.

This flat stock is suited for shop fabrication of tooling, fixtures, and precision components in both production and maintenance environments. The ground finish and tight dimensional tolerances allow parts to be laid out and machined with minimal stock removal. It is appropriate for applications where air-hardening steel with predictable heat-treat behavior is required. The 36-inch length provides a practical working blank for a wide range of tool and die applications.

Key Features

• AISI A2 air-hardening tool steel — stable dimensions during heat treatment
• Thickness tolerance of plus or minus 0.001 inches for consistent stock removal
• Width tolerance of plus 0.000 to 0.005 inches
• Length tolerance of plus 0.25 inches
• Square tolerance of plus or minus 0.001 inches per side
• Edge squareness held to 0.003 inches per inch on all edges

Compatibility

Designed as a standard AISI A2 air-hardening tool steel flat stock suitable for general toolmaking, die fabrication, and precision machining applications where A2 grade material is specified.

Installation Notes

Cutting and machining of tool steel flat stock should be performed by qualified machinists or tool and die makers using appropriate metalworking equipment. Always follow established shop safety practices including proper guarding and eye protection when sawing, grinding, or milling. Heat treatment should be performed according to the material specification for AISI A2 tool steel by a qualified heat treater. Handle ground surfaces carefully to avoid nicks or surface damage that could affect dimensional accuracy.