Starrett 57643 A2 Tool Steel Flat Stock 7/8 X 4 X 18 in

Product Description

The STARRETT 57643 is an A2 air-hardening tool steel flat stock bar measuring 7/8 inch thick, 4 inches wide, and 18 inches long. A2 tool steel is a cold-work die steel known for its excellent dimensional stability during heat treatment, good toughness, and high wear resistance after hardening. It is supplied in the annealed condition, ready for machining and subsequent heat treatment. Machinists, toolmakers, and die makers install this material in job shops, tool rooms, and manufacturing facilities where precision ground flat stock is required for punches, dies, gauges, and cutting tools.

This flat stock is suited to applications in tool and die making, jig and fixture fabrication, and precision instrument manufacturing. The 7/8 x 4 x 18 inch blank size makes it appropriate for medium-to-large die sections, blanking punches, forming tools, and wear plates. The A2 air-hardening designation means the steel reaches full hardness through an air-cool cycle after austenitizing, minimizing distortion compared to oil-hardening grades. It is commonly specified wherever close-tolerance finish dimensions are needed after grinding.

Key Features

• AISI A2 air-hardening tool steel composition for minimal distortion during heat treatment
• Thickness of 7/8 inch with a tolerance of +0.010 to +0.015 inches for predictable stock allowance
• Width of 4 inches with a tolerance of +0.010 to +0.015 inches
• Length of 18 inches with a tolerance of +0.250 inches
• Square tolerance of +0.010 to +0.015 inches for accurate layout and setup
• Supplied in annealed condition for full machinability prior to hardening

Compatibility

Designed as a standard A2 tool steel flat stock blank compatible with conventional toolroom machining, surface grinding, EDM, and heat treatment processes used in tool and die applications.

Installation Notes

Handle flat stock with appropriate lifting equipment given the 17.85-pound shipping weight. Machining should be performed in the annealed state before heat treatment; consult the applicable A2 heat treatment data sheet for austenitizing temperature, soak time, and air-hardening procedure. Secure the workpiece firmly in a vise or fixture before cutting to prevent movement. Always use appropriate PPE including eye protection and gloves when cutting or grinding tool steel.