Starrett 57661 A2 Tool Steel Flat Stock 1-1/4x4x18 in

Product Description

The STARRETT 57661 is an A2 air-hardening tool steel flat stock bar used in toolmaking, die making, and precision machining applications. Measuring 1-1/4 inches thick, 4 inches wide, and 18 inches long, this flat stock is supplied in AISI Type A2 tool steel, a chromium-based air-hardening grade known for its dimensional stability during heat treatment and good wear resistance. Thickness, width, and squareness tolerances are held to +0.010 to 0.015 inches, with a length tolerance of +0.25 inches. The part ships at 25.4 pounds. Machinists, tool and die makers, and metal fabricators typically work with this material in shop environments requiring predictable hardening response and minimal distortion.

A2 air-hardening flat stock is used in the fabrication of punches, dies, gauges, fixtures, and cutting tools across general metalworking, manufacturing, and toolroom applications. The air-hardening characteristic of A2 steel reduces the risk of quench cracking compared to oil-hardening grades, making it a practical choice for larger cross-section tooling components. This piece is sized for single-piece toolroom use or small-batch production applications where a pre-sized flat bar is needed before rough machining and heat treat.

Key Features

• AISI Type A2 air-hardening tool steel for dimensional stability during heat treatment
• Thickness: 1-1/4 inches with +0.010 to 0.015 inches tolerance
• Width: 4 inches with +0.010 to 0.015 inches tolerance
• Length: 18 inches with +0.25 inches tolerance
• Squareness tolerance held to +0.010 to 0.015 inches
• Ships as a single piece at 25.4 pounds

Compatibility

Designed as a standard AISI A2 air-hardening tool steel flat bar for use in general toolroom, die making, and precision machining applications where A2 grade material is specified.

Installation Notes

Machining and heat treatment of A2 tool steel should be performed by qualified machinists or tool and die makers familiar with air-hardening steel procedures. Follow the material supplier and shop safety guidelines for saw cutting, milling, and grinding operations. Appropriate PPE including eye protection and gloves is required when cutting or grinding tool steel. Heat treatment should follow established A2 hardening and tempering parameters sourced from a qualified metallurgical reference or heat treater.