Starrett 54179 O1 Tool Steel Flat Stock 5/8x3x18 in

Product Description

The STARRETT 54179 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die making, and precision machining applications. Cut to 5/8 inch thick, 3 inches wide, and 18 inches long, this bar ships annealed and ready for machining before hardening. Thickness tolerance is held to plus or minus 0.001 inches, and squareness is maintained to 0.003 inches per inch along all edges. At 9.48 pounds, the bar provides substantial stock for toolroom use. It is supplied to AISI Type O1 specifications, making it one of the most widely used oil-hardening grades in precision tooling.

O1 tool steel flat stock is used in toolrooms and machine shops for the fabrication of punches, dies, gauges, jigs, fixtures, and cutting tools. The 18-inch length provides enough stock for a range of short-run tooling projects. This bar is particularly suited for applications where tight dimensional tolerances are required before heat treatment, allowing machinists to rough and finish machine the stock to near-net shape prior to hardening and tempering.

Key Features

• AISI Type O1 oil-hardening tool steel material specification
• Thickness tolerance of plus or minus 0.001 inches for precise pre-hardening machining
• Width tolerance of 0.000 to minus 0.005 inches
• Length tolerance of plus 0.250 inches
• Squareness maintained to 0.003 inches per inch on all edges
• Supplied in annealed condition, ready for machining before heat treatment

Compatibility

Designed as a standard O1 oil-hardening tool steel flat bar for general toolroom and die shop use where AISI Type O1 material specification is required.

Installation Notes

Machining and heat treatment of tool steel should be performed by qualified toolmakers or machinists familiar with O1 oil-hardening steel. O1 steel requires proper annealing, hardening, and tempering procedures to achieve target hardness without cracking. Always follow established shop safety practices when sawing, grinding, or milling tool steel, including the use of appropriate cutting fluids and personal protective equipment. Hardening and tempering operations should reference published heat treatment data for AISI O1 from the steel supplier or a recognized metallurgical reference.