Starrett 57008 O1 Tool Steel Flat Stock 3/8x4x18 in

Product Description

The STARRETT 57008 is a precision-ground O1 oil-hardening tool steel flat stock bar used in toolmaking, die making, jig fabrication, and general machine shop work. It measures 3/8 inch thick, 4 inches wide, and 18 inches long, with a shipping weight of 7.65 pounds. O1 tool steel offers excellent machinability in the annealed state and responds predictably to oil-quench hardening, making it a standard choice for punches, dies, gauges, and cutting tools. Thickness and width tolerances are held to +0.010 to +0.015 inches, and length tolerance is +0.25 inches. Edge squareness is held to 0.003 per inch across all edges.

This flat stock is suited for fabrication environments where a machinable, heat-treatable steel bar stock is required at consistent dimensional tolerances. It is commonly used by tool and die makers, machinists, and maintenance shops producing custom tooling, fixtures, blades, and wear components. At 18 inches in length, the bar accommodates a range of small to mid-size tool blanks without further crosscutting in most applications. Single-piece packaging makes it practical for low-volume or prototype work.

Key Features

• AISI Type O1 oil-hardening tool steel for predictable heat-treat response
• Precision ground to +0.010 to +0.015 inch tolerance on thickness and width
• Edge squareness held to 0.003 per inch on all edges
• Length tolerance of +0.25 inches on the 18-inch bar
• Annealed condition allows standard machining before hardening
• Single-piece minimum order quantity for prototype and low-volume use

Compatibility

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

Installation Notes

Machining should be completed in the annealed state before oil-quench hardening. Heat treatment of tool steel should be performed by qualified personnel following established metallurgical procedures and applicable shop safety protocols. Secure workpieces properly during grinding or milling operations. Consult material data sheets for specific hardening temperature ranges and quench media requirements prior to heat treating.