Starrett 53939 O1 Tool Steel Flat Stock 1/32x2.5x18 in

Product Description

The STARRETT 53939 is an O1 oil-hardening tool steel flat stock bar intended for toolmaking, die work, jigs, fixtures, and precision machining applications. It measures 1/32 inch thick, 2-1/2 inches wide, and 18 inches long, and is produced to AISI Type O1 specification. Thickness and squareness tolerances are held to plus or minus 0.001 inches, making this stock suitable for applications where dimensional consistency matters before heat treatment. At 0.4 pounds, it is a lightweight piece appropriate for small tooling and gauge blanks. Machinists, toolmakers, and die makers are the primary users of this material.

O1 tool steel flat stock is used in general toolroom work where the material will be machined to shape and then oil-quench hardened to final hardness. Typical applications include punches, dies, cutting tools, gauges, and small fixture components in both job shop and production toolroom environments. This piece is sold individually and is sized for bench-scale toolmaking work rather than large production runs.

Key Features

• AISI Type O1 oil-hardening tool steel — machines cleanly in the annealed state and responds to oil quench
• Thickness held to plus or minus 0.001 inches for consistent stock removal calculations
• Width tolerance of 0.000 to minus 0.005 inches provides a predictable fit in slotted fixtures
• Length tolerance of plus 0.250 inches, minus 0 inches ensures stock is never short of nominal
• Edge squareness: all edges held to 0.003 inches per inch
• Individual piece packaging — no minimum order beyond a single piece

Compatibility

Designed as a general-purpose O1 oil-hardening flat stock piece suited for toolroom, die, and fixture fabrication applications where AISI O1 specification material is required.

Installation Notes

O1 tool steel flat stock is worked by machinists and toolmakers using conventional milling, grinding, and sawing equipment in the annealed condition. Heat treatment — including hardening and tempering — should be performed by qualified personnel following established metallurgical procedures for O1 tool steel. Always wear appropriate personal protective equipment when cutting or grinding tool steel. Finished tooling made from this stock must be fully tempered after quench hardening before being placed into service to reduce brittleness.