Starrett 53998 O1 Tool Steel Flat Stock 1/8 X 1/8 X 18 in

Product Description

The STARRETT 53998 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die work, and precision machining applications. Manufactured to AISI Type O1 specifications, this flat stock measures 0.125 inches thick, 0.125 inches wide, and 18 inches long. It holds a thickness tolerance of plus or minus 0.001 inches and a width tolerance of 0.000 to minus 0.005 inches, making it suitable for applications where close dimensional control is required before hardening. Machinists, tool and die makers, and metalworking shops use this stock to fabricate punches, dies, gauges, and similar tooling components.

This flat stock is used in job shops, tool rooms, and manufacturing environments where O1 tool steel is specified for its oil-quench hardening characteristics. The 18-inch length provides enough working material for most bench-scale tooling projects. The square cross-section profile and tight squareness spec of 0.003 inches per inch on all edges make this stock ready for layout and machining with minimal prep. It is appropriate for both prototype and production tooling work.

Key Features

• AISI Type O1 oil-hardening tool steel — designed for oil-quench heat treatment
• Thickness and squareness tolerance of plus or minus 0.001 inches for close-tolerance machining
• Width tolerance of 0.000 to minus 0.005 inches for consistent fit in tooling setups
• Edge squareness held to 0.003 inches per inch on all edges
• Length tolerance of plus 0.250 inches, minus 0 inches — never short of nominal length
• Square 0.125 inches by 0.125 inches cross-section suits small punch, gauge, and die stock applications

Compatibility

Designed as a general-purpose O1 tool steel flat stock for use in tool room and machining environments where AISI Type O1 oil-hardening material is required.

Installation Notes

Tool and die makers typically cut, grind, and machine this stock to finished dimensions before heat treatment. All cutting and grinding operations should be completed prior to oil quenching to avoid distortion of finished features. Standard metalworking toolroom practices and appropriate personal protective equipment apply when machining tool steel. Consult the applicable heat treatment procedure for O1 steel for proper austenitizing temperature and quench guidelines.