Starrett 57055 O1 Tool Steel Flat Stock 1x1.25x18 in

Product Description

The STARRETT 57055 is an O1 oil-hardening tool steel flat stock bar measuring 1 inch thick, 1-1/4 inches wide, and 18 inches long. Manufactured to AISI Type O1 specification, this tool steel is designed for applications requiring a material that can be hardened through oil-quenching to achieve high hardness and wear resistance. Machinists, tool-and-die makers, and metalworking shops use O1 flat stock to fabricate punches, dies, gauges, cutting tools, and other precision tooling components. Tolerances are held to +0.010 to 0.015 inches on thickness and width, and +0.250 inches on length, with edge squareness held to 0.003 per inch.

This flat stock is suited for job shops, tool rooms, and production environments where O1 tool steel stock is kept on hand for custom tooling fabrication. The 18-inch length allows multiple blanks to be cut from a single piece. O1 is a general-purpose oil-hardening steel widely used in low-to-medium production tooling where dimensional stability after heat treatment is important. It machines well in the annealed condition and responds predictably to oil-quench hardening and tempering cycles performed by qualified heat treaters or in-house tool room operations.

Key Features

• AISI Type O1 oil-hardening tool steel for predictable heat treatment response
• Thickness tolerance of +0.010 to 0.015 inches for consistent stock removal planning
• Width tolerance of +0.010 to 0.015 inches
• Length tolerance of +0.250 inches
• Edge squareness held to 0.003 inches per inch on all edges
• Ships as a single flat bar — no minimum beyond one piece

Compatibility

Designed as a standard O1 oil-hardening tool steel flat stock blank for use in tool room and metalworking applications requiring AISI Type O1 material in 1 inch thick by 1-1/4 inch wide cross-section.

Installation Notes

O1 tool steel flat stock is worked and shaped by qualified machinists and tool-and-die makers using conventional milling, grinding, and sawing equipment. Material is typically supplied in the annealed condition and must be hardened and tempered by a qualified heat treater before use in wear or cutting applications. Allow for stock removal on all faces when planning finish dimensions, accounting for the stated tolerances. Follow applicable shop safety practices when cutting, grinding, or heat-treating tool steel.