Starrett 54309 O1 Tool Steel Flat Stock 1/8x4x36

Product Description

The STARRETT 54309 is an O1 oil-hardening tool steel flat stock bar used in precision toolmaking, die making, and machining applications. Manufactured to AISI Type O1 specifications, this flat stock measures 0.125 inches thick, 4 inches wide, and 36 inches long and weighs 5.1 pounds. Thickness tolerance is held to plus or minus 0.001 inches, length tolerance is plus 0.015 inches, and width tolerance runs from 0.000 to minus 0.005 inches. Squareness is maintained at 0.003 inches per inch on all edges. O1 tool steel offers good machinability in the annealed state and responds well to oil quench hardening, making it a reliable choice for shop-made tooling, jigs, fixtures, and punches.

This flat stock is suited for toolrooms, machine shops, and maintenance departments that need precision-ground stock ready for layout, machining, and heat treating. It is commonly used to fabricate punches, dies, cutting tools, gauges, and custom fixtures where tight dimensional control is required before and after hardening. The 36-inch length provides enough material for multiple shorter workpieces from a single bar. Machinists and tool and die makers working with conventional or CNC equipment will find this stock ready to mark out and cut to size.

Key Features

• AISI Type O1 oil-hardening tool steel for predictable heat treat response
• Thickness held to plus or minus 0.001 inches for precise layout and fit-up
• All edges square to within 0.003 inches per inch
• 36-inch length yields multiple workpieces from a single bar
• Width tolerance from 0.000 to minus 0.005 inches supports close-tolerance applications
• Good machinability in annealed condition prior to hardening

Compatibility

Designed as a general-purpose O1 oil-hardening tool steel flat stock suitable for toolroom, die shop, and precision machining applications requiring AISI Type O1 material specification.

Installation Notes

O1 tool steel flat stock is worked by machinists and tool and die makers using conventional milling, grinding, sawing, and drilling equipment. Wear appropriate personal protective equipment when cutting or grinding. Heat treating to final hardness should follow established oil quench procedures for AISI O1 and should be performed by qualified personnel using calibrated furnace equipment. Always allow stock to reach ambient temperature before taking finish measurements.