Starrett 53933 O1 Tool Steel Flat Stock 1/32x1/2x18 in

Product Description

The STARRETT 53933 is an O1 oil-hardening tool steel flat stock bar used in precision toolmaking, die making, and machine shop fabrication. It is manufactured from AISI Type O1 tool steel, a widely used oil-hardening grade known for its dimensional stability and ease of machining before heat treatment. The bar measures 1/32 inch thick, 1/2 inch wide, and 18 inches long, with a thickness tolerance of plus or minus 0.001 inches and a squareness tolerance of 0.003 inches per inch on all edges. Machinists, tool and die makers, and maintenance technicians reach for this stock when building or repairing punches, dies, gauges, and fixtures that require hardening after final shaping.

This flat stock is suited for job shops, toolrooms, and maintenance departments in both light manufacturing and heavy industrial settings. It is sized for small, precision applications where tight thickness and squareness tolerances matter. The 18-inch length accommodates most bench-scale toolmaking tasks and can be cut to final length on a metal-cutting saw or surface grinder. Width tolerance runs from 0.000 to minus 0.005 inches, and length tolerance allows a plus 0.250-inch overage with no minus deviation, which is standard for this class of bar stock.

Key Features

• AISI Type O1 oil-hardening tool steel for reliable heat-treat response in standard shop practice
• Thickness tolerance of plus or minus 0.001 inches for close-tolerance toolmaking
• Squareness held to 0.003 inches per inch on all edges
• Width tolerance of 0.000 to minus 0.005 inches ensures consistent fit in die sets and fixtures
• Length tolerance of plus 0.250 inches with no minus deviation — stock is never short
• Single-piece package quantity suitable for one-off toolroom jobs

Compatibility

Designed as a standard O1 oil-hardening tool steel flat bar for general toolroom and die-making applications where AISI Type O1 material specification is required.

Installation Notes

O1 tool steel flat stock is typically machined, ground, or filed to final dimensions before oil-quench hardening and tempering by a qualified machinist or tool and die maker. All grinding and cutting operations should be completed in the annealed (soft) state prior to heat treatment. Follow established heat-treating procedures for AISI O1 tool steel regarding austenitizing temperature, quench media, and tempering cycle — do not substitute water or brine for the required oil quench. Wear appropriate PPE when cutting, grinding, or handling freshly hardened stock.