Starrett 54399 O1 Tool Steel Flat Stock 5/16x3x36 in

Product Description

The STARRETT 54399 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die making, and precision machining applications. Manufactured from AISI Type O1 tool steel, it measures 5/16 inch thick, 3 inches wide, and 36 inches long, and weighs approximately 9.56 pounds. O1 is a general-purpose oil-hardening tool steel known for good machinability in the annealed state, dimensional stability during heat treatment, and the ability to hold a sharp edge after hardening. This stock is supplied in flat bar form and is intended for fabrication into punches, dies, gauges, jigs, and similar tooling components by machinists, tool and die makers, and industrial maintenance technicians.

This flat stock is suited for job shops, toolrooms, and maintenance departments that require precision-ground stock with tight dimensional tolerances. It is appropriate for applications where the bar will be machined or ground to final dimensions before oil-quench hardening. The 36-inch length provides enough material for multiple tooling blanks from a single piece. It is a standard choice for short-run die components, precision fixtures, and custom cutting tools where O1 tool steel properties are specified by the engineer or designer.

Key Features

• AISI Type O1 oil-hardening tool steel construction for consistent heat-treat response
• Thickness tolerance of plus or minus 0.001 inches for precise fitment in tooling applications
• Width tolerance of minus 0.000 to minus 0.005 inches to ensure clean fit in mating components
• Length tolerance of plus 0.015 inches, minus 0 inches
• Edge squareness held to 0.003 inches per inch on all edges
• Supplied annealed for full machinability prior to hardening

Compatibility

Designed as a standard O1 oil-hardening tool steel flat bar for use in general toolmaking, die making, and precision fabrication wherever AISI Type O1 material is specified.

Installation Notes

Cutting, grinding, and machining should be performed in the annealed condition before heat treatment. Oil quenching and tempering should be carried out by qualified personnel following established heat-treat procedures for AISI O1 tool steel. Proper personal protective equipment is required during cutting and grinding operations. Final grinding after hardening should account for any dimensional movement during heat treatment.