Starrett 57591 A2 Tool Steel Flat Stock 5/16 X 3/4 X 18 in

Product Description

The STARRETT 57591 is an A2 air-hardening tool steel flat stock bar supplied in a ready-to-machine condition. It measures 5/16 inches thick, 3/4 inches wide, and 18 inches long, with a weight of 1.2 pounds. A2 tool steel is known for its excellent dimensional stability during heat treatment, making it a reliable choice for toolmakers, machinists, and die makers who require tight dimensional control through hardening cycles. The 57591 is produced to AISI Type A2 material specification and holds thickness, width, and square tolerances of +0.010 to +0.015 inches, with a length tolerance of +0.25 inches.

This flat stock is suited for fabrication of punches, dies, gauges, forming tools, and similar precision tooling components in job shop and industrial manufacturing environments. Its air-hardening characteristic minimizes warping and cracking compared to oil or water-hardening grades, making it a practical choice for intricate or close-tolerance tooling work. It is sold in single-piece quantity and is ready for layout, machining, and subsequent heat treatment by the end user.

Key Features

• AISI A2 air-hardening tool steel construction for dimensional stability during heat treat
• Thickness of 5/16 inches with +0.010 to +0.015 inch tolerance
• Width of 3/4 inches with +0.010 to +0.015 inch tolerance
• Length of 18 inches with +0.25 inch tolerance
• Square tolerance of +0.010 to +0.015 inches
• Single-piece packaging suitable for low-quantity toolroom use

Compatibility

Designed as an OEM-style flat stock bar for general toolroom and machining applications requiring AISI A2 air-hardening tool steel in the 5/16 inches by 3/4 inches cross-section profile.

Installation Notes

Machining and heat treatment of A2 tool steel should be performed by a qualified machinist or toolmaker. Material should be stress-relieved or annealed before machining if required, and all cutting operations should follow standard tool steel practices. Heat treatment, including hardening and tempering, must be performed in controlled atmosphere or vacuum furnace conditions to maintain surface integrity. Always consult applicable material data sheets and shop safety procedures when grinding or machining tool steel stock.