Starrett 54409 O1 Tool Steel Flat Stock 3/8x1x36 in

Product Description

The STARRETT 54409 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die making, jig building, and precision machining applications. It measures 3/8 inches thick, 1 inch wide, and 36 inches long, and weighs 3.82 pounds. Manufactured to AISI Type O1 Oil Hardening specification, this flat stock holds tight dimensional tolerances: thickness tolerance of plus or minus 0.001 inches, width tolerance of minus 0 to minus 0.005 inches, and length tolerance of plus 0.015 inches. Edge squareness is held to 0.003 inches per inch. Machinists, tool and die makers, and precision fabricators select O1 flat stock when they need a material that machines cleanly in the annealed state and hardens predictably with an oil quench.

O1 tool steel flat stock is a standard material for making punches, dies, gauges, cutting tools, and fixture components in both job shop and production environments. This bar arrives in the annealed (soft) condition, making it suitable for milling, drilling, grinding, and EDM operations before heat treatment. It is well suited for low-to-medium production tooling where dimensional stability after hardening is a priority. Tool and die makers working in metal fabrication, stamping, and precision machining shops commonly stock this size for general-purpose tooling work.

Key Features

• AISI Type O1 Oil Hardening tool steel — machines cleanly in annealed state and responds consistently to oil-quench heat treatment
• Thickness tolerance of plus or minus 0.001 inches for precise stock removal planning
• Width tolerance of minus 0 to minus 0.005 inches
• Length tolerance of plus 0.015 inches
• Edge squareness held to 0.003 inches per inch across all edges
• Ready for milling, grinding, drilling, and EDM in the as-supplied annealed condition

Compatibility

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

Installation Notes

O1 tool steel flat stock is machined and heat treated by tool and die makers and precision machinists. All cutting, grinding, and drilling operations should be completed in the annealed state prior to hardening. Heat treatment involving oil quenching should be performed by qualified personnel following established metallurgical procedures and applicable shop safety protocols. Personal protective equipment appropriate for hot work is required during any heat-treat operations.