Starrett 57239 O1 Tool Steel Flat Stock 1/4 X 14 X 36 in

Product Description

The STARRETT 57239 is an O1 oil-hardening tool steel flat stock bar measuring 0.25 inches thick, 14 inches wide, and 36 inches long. Manufactured to AISI Type O1 material specification, this flat stock is produced from tool steel known for its excellent dimensional stability and machinability in the annealed state before hardening. Thickness tolerance is held to plus or minus 0.001 inches, giving machinists and toolmakers a reliable starting dimension for die making, jig fabrication, punch tooling, and precision fixture work. At 35.7 pounds per piece, this is a substantial bar suited for heavy tooling applications requiring a large working cross-section.

O1 oil-hardening tool steel flat stock in this size is used in industrial and job-shop environments where large-format tooling blanks are required. Typical applications include die plates, stripper plates, forming tools, and machine components that will be rough-machined in the annealed condition and then oil-quench hardened to finished hardness. This stock is handled and processed by tool and die makers, machinists, and precision fabricators working in metalworking shops, maintenance departments, and prototype facilities. The 14-inch width makes it suitable for wide die sets or large fixture plates that cannot be built up from narrower stock.

Key Features

• AISI Type O1 oil-hardening tool steel for consistent heat treat response
• Thickness held to plus or minus 0.001 inches for precision layout and machining
• Length tolerance of plus 0.015 inches, zero minus, ensuring full usable length
• Width tolerance of 0.000 to minus 0.015 inches for predictable fit in die sets
• Edge squareness of 0.003 inches per inch on all edges
• Large 14 inches by 36 inches format supports wide tooling and fixture blanks

Compatibility

Designed as a standard AISI O1 oil-hardening tool steel flat stock for use in tool and die making, fixture fabrication, and precision machining applications requiring annealed stock that responds to conventional oil-quench heat treatment.

Installation Notes

Handling and machining of tool steel flat stock should be performed by qualified machinists or tool and die makers using appropriate metal-cutting equipment. Material arrives in the annealed condition and must be heat treated by a qualified heat treater or tool room following established oil-quenching procedures for O1 tool steel before placing into service as a hardened component. Wear appropriate personal protective equipment when sawing, milling, or grinding. Secure the workpiece firmly before any machining operation given the weight of this bar.