Starrett 54339 O1 Tool Steel Flat Stock 3/16x3/4x36 in

Product Description

The STARRETT 54339 is an O1 oil-hardening tool steel flat stock bar intended for toolmaking, jig building, die making, and precision machining applications. Manufactured to AISI Type O1 specification, this flat stock measures 3/16 inches thick, 3/4 inches wide, and 36 inches long, with a weight of 1.43 pounds. Thickness tolerance is held to plus or minus 0.001 inches, supporting close-tolerance work where dimensional consistency directly affects part quality. Machinists, tool and die makers, and metal fabricators typically source this material for shop-made cutting tools, punches, gauges, and fixtures that require subsequent heat treatment.

O1 tool steel is a general-purpose oil-hardening grade suited for low-to-medium production tooling in both shop and industrial environments. The 36-inch length provides a full bar that can be cut to finished blank lengths as the application demands. Its predictable oil-quench hardening response makes it a common first choice when machining a blank to near-net shape before hardening and tempering. Width tolerance is held to minus 0.000 to minus 0.005 inches. Length tolerance is plus 0.015 inches with no minus allowance. Edge squareness is 0.003 inches per inch across all edges.

Key Features

• AISI Type O1 oil-hardening tool steel for predictable heat-treat response
• Thickness: 3/16 inches with plus or minus 0.001 inch tolerance
• Width: 3/4 inches with 0.000 to minus 0.005 inch tolerance
• Length: 36 inches with plus 0.015 inch tolerance
• Edge squareness held to 0.003 inches per inch on all edges
• Ready for machining to finished blank dimensions prior to hardening

Compatibility

Designed as a general-purpose O1 oil-hardening tool steel flat bar compatible with standard toolmaking, die making, and precision fabrication applications requiring AISI Type O1 material specification.

Installation Notes

Cutting, grinding, and machining should be performed in the annealed (soft) condition before heat treatment. Eye protection, appropriate cutting fluid, and secure workholding are standard practice when cutting tool steel flat bar. Heat treatment including hardening and tempering should be performed by qualified personnel following established metallurgical procedures for AISI O1 tool steel. Consult applicable shop safety and OSHA standards when operating metalworking equipment.