Starrett 54075 O1 Tool Steel Flat Stock 1/4x1-3/4x18 in

Product Description

The STARRETT 54075 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die work, jig fabrication, and precision machining applications. Manufactured to AISI Type O1 specification, this flat stock measures 0.25 inches thick, 1.75 inches wide, and 18 inches long, and weighs 2.24 pounds. Thickness tolerance is held to plus or minus 0.001 inches, making it suitable for applications where dimensional consistency is critical before and after heat treatment. Machinists, tool-and-die makers, and metalworking professionals stock O1 flat bar as a versatile raw material for custom tooling and fixture components.

O1 tool steel flat stock is used across a wide range of precision metalworking environments including job shops, maintenance departments, and production toolrooms. It is well-suited for applications requiring a steel that machines cleanly in the annealed state and responds predictably to oil-quench hardening. Typical uses include punches, dies, gauges, jigs, fixtures, and cutting tools. This bar arrives in the soft-annealed condition, ready for machining prior to heat treatment.

Key Features

• AISI Type O1 oil-hardening tool steel — machines well in annealed state, hardens with oil quench
• Thickness held to plus or minus 0.001 inches for consistent pre-grind stock allowance
• Width tolerance of 0.000 to minus 0.005 inches for predictable fit in standard tool slots
• Length tolerance of plus 0.250 inches, minus 0 inches — stock arrives at or above nominal length
• Edge squareness held to 0.003 inches per inch across all edges
• Single-piece minimum order quantity — suitable for low-volume toolroom use

Compatibility

Designed as a standard AISI O1 oil-hardening tool steel flat bar suitable for general toolmaking, die making, and precision fixture fabrication where oil-quench heat treatment will be applied.

Installation Notes

O1 flat stock is typically processed by tool-and-die makers or machinists using conventional milling, grinding, and sawing equipment. The bar should be machined to near-final dimensions before heat treatment, as post-hardening grinding will be required to achieve final tolerances. Oil-quench hardening should be performed by a qualified heat treater following established protocols for AISI O1 tool steel. Allow the bar to reach a uniform temperature before quenching to minimize distortion.