Starrett 57339 A2 Tool Steel Flat Stock 5/16x5/16x36 in

Product Description

The STARRETT 57339 is an A2 air-hardening tool steel flat stock bar measuring 5/16 inches thick by 5/16 inches wide by 36 inches long. A2 tool steel is a versatile air-hardening alloy known for its dimensional stability during heat treatment and good wear resistance, making it a go-to material for fabricating dies, punches, gauges, and cutting tools. This bar ships in an annealed condition and is ready for machining before hardening. At 1.14 pounds per bar, it is well suited for toolroom use and light toolmaking applications where close tolerances are required. Machinists, tool and die makers, and maintenance technicians working in fabrication and manufacturing environments are the primary users of this stock.

This flat stock is used in toolroom and production environments where consistent cross-section, tight tolerances, and predictable heat-treat response are required. Typical applications include fabricating punches, die components, form tools, fixture components, and precision gauging parts. The 36-inch length provides practical stock for multiple smaller parts from a single bar, reducing material waste in low-volume toolmaking. The square cross-section at 5/16 inches x 5/16 inches makes it directly usable without additional milling for many standard toolroom shapes.

Key Features

• AISI A2 air-hardening tool steel construction for dimensional stability during hardening
• Thickness and square tolerance held to plus or minus 0.001 inches for close-tolerance toolmaking
• Width tolerance of plus 0.000 to 0.005 inches ensures consistent fit in standard toolholders and fixtures
• Length tolerance of plus 0.25 inches provides usable full-length stock without undersize cuts
• Squareness specification of 0.003 inches per inch on all edges supports accurate layout and machining reference
• 36-inch bar length suitable for multiple part blanks from a single piece

Compatibility

Designed as a standard A2 air-hardening tool steel flat stock bar suitable for general toolroom fabrication requiring AISI A2 material specification.

Installation Notes

A2 tool steel flat stock is machined and ground in the annealed condition before heat treatment. Use appropriate carbide or high-speed tooling and cutting fluids when machining. Air hardening is performed by a qualified heat treater following established procedures for A2 steel. Always allow bars to reach ambient temperature before precision measurement to avoid thermal expansion errors.