Starrett 54427 O1 Tool Steel Flat Stock 7/16x1/2x36 in

Product Description

The STARRETT 54427 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die making, and precision machining applications. Manufactured to AISI Type O1 specifications, this flat stock measures 7/16 inches thick, 1/2 inches wide, and 36 inches long, with a weight of 2.23 pounds. Thickness tolerance is held to plus or minus 0.001 inches, making it suitable for applications where dimensional accuracy is critical before and after heat treatment. Licensed machinists, tool and die makers, and industrial maintenance technicians work with this material to fabricate punches, dies, gauges, and cutting tools.

This flat stock is intended for use in tool and die shops, maintenance repair facilities, and precision fabrication environments. Its O1 oil-hardening designation means it responds well to conventional oil quench hardening, allowing machinists to rough machine the bar in its annealed state and then harden to a working tool surface. The 36-inch length provides sufficient stock for multiple tool blanks from a single bar. It is a standard choice for low-to-medium production tooling where high dimensional stability and good machinability in the annealed condition are required.

Key Features

• AISI Type O1 oil-hardening tool steel for consistent heat treat response
• Thickness held to plus or minus 0.001 inches for close-tolerance blanks
• Width tolerance of 0.0000 to 0.005 inches, length tolerance of plus 0.015 inches
• Squareness: edge all 0.003 inches per inch for reliable reference surfaces
• 36-inch length yields multiple tool blanks from a single piece
• Ships as a single bar with no minimum order beyond one piece

Compatibility

Designed as a standard O1 oil-hardening tool steel flat bar suitable for general toolmaking, die making, and precision machining applications requiring AISI Type O1 material specification.

Installation Notes

This material is supplied in the annealed condition and should be machined prior to hardening. Heat treatment should be performed by a qualified tool and die maker or heat treat technician following accepted practices for AISI O1 tool steel. Always wear appropriate PPE when cutting, grinding, or machining tool steel bar stock. Follow applicable shop safety codes and equipment manufacturer guidelines when operating saws, mills, or grinders on this material.