Starrett 54189 O1 Tool Steel Flat Stock 3/4x1-1/4x18 in

Product Description

The STARRETT 54189 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die work, and precision machining applications. Manufactured to AISI Type O1 specification, this flat stock measures 0.75 inches thick, 1.25 inches wide, and 18 inches long, weighing 4.78 pounds. Thickness tolerance is held to plus or minus 0.001 inches, making it suitable for applications where dimensional consistency before hardening is critical. Machinists, tool and die makers, and industrial maintenance technicians work with O1 flat stock when they need a versatile, oil-quenched tool steel that machines cleanly in the annealed state and achieves good hardness after heat treatment.

O1 tool steel flat stock is used in a wide range of shop and production environments. Common applications include punches, dies, gauges, cutting tools, and fixtures where moderate wear resistance and toughness are required. This bar is supplied in the soft-annealed condition, ready for machining prior to heat treat. It is suited for job shops, tool rooms, and maintenance departments that require precision-ground flat stock in small quantities, with a minimum order quantity of one piece.

Key Features

• AISI Type O1 oil-hardening tool steel for reliable heat-treat response
• Thickness held to plus or minus 0.001 inches for precise pre-grind stock allowance
• Width tolerance of 0.0000 to minus 0.005 inches for consistent fit in close-tolerance applications
• Length tolerance of plus 0.250 inches ensures full usable length
• Edge squareness held to 0.003 inches per inch on all edges
• Supplied in annealed condition, ready for machining and subsequent oil quench hardening

Compatibility

Designed as a standard AISI O1 oil-hardening tool steel flat bar suitable for general toolmaking, die making, and precision fixture fabrication where O1 specification material is required.

Installation Notes

O1 tool steel flat stock is worked by machinists and tool and die makers using conventional milling, grinding, and sawing equipment. Always follow established heat-treatment procedures for O1 tool steel, including proper preheat, hardening temperature, and oil quench, as specified by the material manufacturer or a qualified metallurgical reference. Wear appropriate PPE when cutting or grinding tool steel. Consult applicable shop safety standards before performing heat-treat operations.