Starrett 54417 O1 Tool Steel Flat Stock 3/8x4x36 in

Product Description

The STARRETT 54417 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die making, and precision machining applications. Manufactured to AISI Type O1 specifications, this flat stock measures 3/8 inch thick, 4 inches wide, and 36 inches long, weighing approximately 15.3 pounds. Tight dimensional tolerances — held to plus or minus 0.001 inches on thickness and squareness — make it a reliable choice when close stock removal is required before hardening. Licensed machinists, tool and die makers, and metalworking professionals use this stock as a starting material for punches, dies, gauges, and custom tooling components.

O1 tool steel is a general-purpose oil-hardening grade well suited to low- to medium-production tooling where dimensional stability after heat treat is important. This flat bar is appropriate for shop environments producing jigs, fixtures, and cutting tools. At 36 inches in length, a single bar provides enough stock for multiple short blanks or one full-length workpiece without additional splicing or welding. The 4-inch width accommodates wide die plates and larger gauge blocks without requiring gang clamping of narrower pieces.

Key Features

• AISI Type O1 oil-hardening tool steel for consistent hardenability and dimensional stability
• Thickness tolerance held to plus or minus 0.001 inches for close-tolerance machining
• Width tolerance of 0.000 to minus 0.005 inches for predictable stock removal
• Length tolerance of plus 0.015 inches, minus 0 inches — always at or above nominal
• Edge squareness: all edges held to 0.003 inches per inch
• Ships as a single bar with no minimum order beyond one piece

Compatibility

Designed as a standard AISI Type O1 oil-hardening tool steel flat bar for use in conventional toolmaking, die making, and precision machining applications requiring a machinable, oil-quench hardenable steel stock.

Installation Notes

Cutting and machining of tool steel flat stock should be performed by qualified machinists using appropriate coolant and carbide or high-speed-steel tooling. Heat treatment — including austenitizing temperature, quench media, and tempering cycles — must follow established procedures for AISI O1 steel and should be performed by a qualified heat treater. Always use appropriate personal protective equipment when cutting, grinding, or handling steel bar stock. Edges as-received may be sharp; deburr before handling or measuring.