Starrett 57179 A2 Tool Steel Flat Stock 5/16x1-1/4x18in

Product Description

The STARRETT 57179 is an A2 air-hardening tool steel flat stock bar suited for toolmaking, die work, and precision machining applications. It ships in an annealed condition ready for machining, then hardens by air quenching after heat treatment. The bar measures 5/16 inches thick, 1-1/4 inches wide, and 18 inches long, with a shipping weight of 1.99 pounds. Thickness, width, and square tolerances are held to +0.010 to 0.015 inches, and length tolerance is +0.25 inches. Machinists, tool-and-die makers, and metalworking shops are the primary users of this material.

A2 tool steel is a general-purpose air-hardening grade known for its balance of wear resistance and toughness. This flat stock is commonly used in cutting tools, punches, dies, gauges, and form tools. The air-hardening characteristic reduces distortion during heat treatment compared to oil-hardening grades, making it a preferred choice when dimensional stability after hardening is critical. This bar size is practical for short-run tooling and prototype work where a standard stock dimension fits the application without requiring custom rolling.

Key Features

• AISI A2 air-hardening tool steel — reduced distortion during heat treatment compared to oil-hardening grades
• Dimensions: 5/16 inches thick x 1-1/4 inches wide x 18 inches long
• Thickness and width tolerances: +0.010 to 0.015 inches
• Square tolerance: +0.010 to 0.015 inches
• Length tolerance: +0.25 inches
• Supplied in annealed condition for machining prior to hardening

Compatibility

Designed for use as a general-purpose A2 tool steel flat stock in toolmaking, die-making, and precision machining applications where an air-hardening grade is specified.

Installation Notes

Machining and heat treatment of tool steel should be performed by qualified machinists or tool-and-die makers using appropriate equipment. Material should be stress-relieved and properly preheated before hardening per the material specification for A2 tool steel. Use appropriate PPE when cutting, grinding, or heat-treating this stock. Follow applicable shop safety and OSHA standards for metalworking operations.