Starrett 59139 O1 Tool Steel Flat Stock 1/64x1/2x36 in

Product Description

The STARRETT 59139 is an O1 oil-hardening tool steel flat stock bar designed for precision toolmaking, die work, gauges, punches, and other applications requiring tight dimensional tolerances and consistent material properties before heat treatment. Manufactured to AISI Type O1 specification, this flat stock measures 1/64 inch thick by 1/2 inch wide by 36 inches long. Thickness tolerance is held to +/- 0.001 inch, making it suitable for applications where stock-to-finished-dimension allowances must be carefully controlled. Machinists, tool and die makers, and maintenance professionals use O1 flat stock as a starting material that responds predictably to oil-quench hardening processes.

This flat stock is suited for job shop and maintenance machining environments where small-section tool steel is needed for fabricating custom blades, wear strips, forming tools, and similar components. The 36-inch length provides a standard working blank that can be cut to length on a metal-cutting bandsaw or mill. Its small cross-section makes it practical for fine tooling applications in both production and repair settings. Width tolerance is held to 0.000 to -0.005 inch, and length tolerance is +0.015 inch, supporting layout and fit-up work with minimal secondary stock removal.

Key Features

• AISI Type O1 oil-hardening tool steel material specification
• Thickness of 1/64 inch with +/- 0.001 inch tolerance for precise fit-up
• Width of 1/2 inch with 0.000 to -0.005 inch tolerance
• Length of 36 inches with +0.015 inch tolerance
• Edge squareness held to 0.003 inch per inch across all edges
• Single-piece packaging suitable for one-off toolmaking and repair work

Compatibility

Designed as a standard AISI O1 oil-hardening tool steel flat stock suitable for general toolmaking, die making, and precision machining applications where oil-quench hardenable steel in small flat-bar form is required.

Installation Notes

Cutting, grinding, and machining of tool steel flat stock should be performed by qualified machinists or tool and die makers using appropriate metalworking equipment. All heat treatment, including oil-quench hardening and tempering, should follow established metallurgical procedures for AISI O1 tool steel and be performed by qualified personnel. Secure workpieces firmly before any cutting or grinding operations, and use appropriate personal protective equipment including eye and hand protection. Do not attempt to bend or straighten this stock cold at thicknesses that would risk fracture, particularly after any hardening operation.