Starrett 54175 O1 Tool Steel Flat Stock 5/8x1-1/4x18 in

Product Description

The STARRETT 54175 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die work, and precision machining applications. Manufactured to AISI Type O1 specification, this flat stock measures 0.625 inches thick, 1.25 inches wide, and 18 inches long, with a weight of 3.99 pounds. Thickness tolerance is held to +/- 0.001 inches, making it suitable for applications requiring close dimensional control before and after heat treatment. O1 tool steel offers good machinability in the annealed state and responds well to oil-quench hardening, which is why it remains a standard choice for punches, dies, gauges, and cutting tools.

This flat stock is used in job shops, tool and die rooms, and maintenance departments where custom tooling is fabricated in-house. It is appropriate for applications that require a material that can be machined to near-final dimensions, then hardened and ground to finish size. Typical uses include blanking dies, forming tools, drill jigs, and precision fixtures. The 18-inch length provides a practical starting blank for most small-to-medium tooling projects, and the controlled tolerances reduce the amount of stock removal required before heat treat.

Key Features

• AISI Type O1 oil-hardening tool steel for predictable hardening response with minimal distortion
• Thickness held to +/- 0.001 inches for close-tolerance tooling blanks
• Width tolerance of 0.0000 to 0.0050 inches under nominal
• Length tolerance of +0.250 inches, never undersize
• Edge squareness of 0.003 inches per inch across all edges
• Ships as a single piece at 3.99 pounds, ready for immediate machining

Compatibility

Designed as a standard AISI O1 oil-hardening tool steel flat stock blank suitable for general toolmaking, die making, and precision fixture fabrication where oil-quench hardenable material is specified.

Installation Notes

Cutting and machining of tool steel flat stock should be performed by a qualified machinist using appropriate tooling for high-carbon steel. Always wear appropriate PPE when cutting, grinding, or heat treating. Heat treatment, including hardening and tempering, should follow established procedures for AISI O1 tool steel and be performed by personnel experienced with tool steel metallurgy. Allow the part to reach ambient temperature before final dimensional inspection.