Starrett 57640 A2 Tool Steel Flat Stock 7/8x2.5x18 in

Product Description

The STARRETT 57640 is an A2 air-hardening tool steel flat stock bar intended for toolmakers, machinists, and die makers who require tight-tolerance raw material for fabricating punches, dies, gauges, and similar precision tooling. The bar measures 7/8 inch thick, 2-1/2 inches wide, and 18 inches long, weighing 11.16 pounds. Thickness, width, and square tolerances are held to +0.010 to 0.015 inches, and length tolerance is +0.25 inches, making this stock suitable for close-tolerance machining and grinding operations without extensive preliminary stock removal.

A2 air-hardening tool steel is commonly used in job shops, toolrooms, and industrial maintenance environments where dimensional stability and wear resistance after heat treatment are required. This flat bar is appropriate for fabricating forming dies, blanking punches, shear blades, and other tooling components that undergo air-hardening heat treatment. It is machined and ground in the annealed condition, then heat treated to final hardness by the end user or a commercial heat treater following AISI A2 specification guidelines.

Key Features

• AISI A2 air-hardening tool steel — offers good dimensional stability during heat treatment
• Thickness: 7/8 inches with +0.010 to 0.015 inch tolerance
• Width: 2-1/2 inches with +0.010 to 0.015 inch tolerance
• Length: 18 inches with +0.25 inch tolerance
• Square tolerance: +0.010 to 0.015 inches for consistent cross-section geometry
• Pre-cut flat stock format reduces setup time compared to full-length bar stock

Compatibility

Designed as a standard AISI A2 air-hardening tool steel flat stock suitable for general toolroom and die-making applications requiring this material specification.

Installation Notes

Machining and grinding of A2 tool steel should be performed in the annealed condition using appropriate cutting fluids and tooling rated for tool steel. Heat treatment to final hardness must be performed by a qualified heat treater following established AISI A2 procedures. Always allow the bar to reach ambient temperature before precision measuring or final grinding. Wear appropriate PPE when cutting or grinding tool steel stock.