Starrett 54180 O1 Tool Steel Flat Stock 5/8x3.5x18 in

Product Description

The STARRETT 54180 is an O1 oil-hardening tool steel flat stock bar used in precision toolmaking, die making, and fixture fabrication. It measures 5/8 inch thick, 3-1/2 inches wide, and 18 inches long, with a weight of 11.02 pounds. The material conforms to AISI Type O1 specification, a general-purpose oil-hardening grade known for good machinability and dimensional stability during heat treat. Thickness tolerance is held to plus or minus 0.001 inch, making it suitable for applications that require tight dimensional control before and after hardening. Machinists and tool and die makers are the primary installers of this stock.

This flat stock is used in shops producing punches, dies, gauges, cutting tools, and general toolroom components. The 18-inch length is a standard toolroom cut that suits typical die set and fixture build-outs. The material ships in an annealed condition, allowing conventional machining before oil-quench hardening. Squareness is held to an edge specification of 0.003 inch per inch, which reduces setup time when referenced directly off the mill.

Key Features

• AISI Type O1 oil-hardening tool steel, annealed and ready to machine
• Thickness tolerance of plus or minus 0.001 inch for precision stock removal planning
• Width tolerance of 0.0000 to 0.0050 inch under nominal
• Length tolerance of plus 0.250 inch, minus 0 inch
• Edge squareness held to 0.003 inch per inch on all edges
• Standard toolroom flat bar suitable for dies, punches, gauges, and fixtures

Compatibility

Designed as a standard O1 oil-hardening tool steel flat stock for use in general toolroom, die making, and precision machining applications requiring a ground or cold-drawn flat bar in AISI Type O1 material specification.

Installation Notes

O1 tool steel flat stock is processed by machinists and tool and die makers using conventional milling, grinding, and drilling equipment. Material is supplied in an annealed state and must be heat treated by a qualified heat treat technician to achieve final hardness. Follow the material supplier heat treat guidelines for preheat, austenitizing temperature, and oil quench procedures specific to AISI O1 grade. Wear appropriate PPE when cutting or grinding tool steel stock.