Starrett 54105 O1 Tool Steel Flat Stock 5/16x1-1/4x18 in

Product Description

The STARRETT 54105 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, jig fabrication, die-making, and precision machining applications. Manufactured to AISI Type O1 specifications, it measures 5/16 inches thick, 1-1/4 inches wide, and 18 inches long. Thickness tolerance is held to +/- 0.001 inches, making it suitable for applications requiring close dimensional control before heat treatment. The O1 grade offers good machinability in the annealed state and responds well to oil quenching. This stock is primarily handled by tool and die makers, machinists, and metalworking professionals who machine it to shape before hardening.

This flat stock is suited for small-run tooling, custom gauges, blanking punches, forming dies, and fixture components in job shops and manufacturing facilities. Because it is supplied in the annealed (soft) condition, it can be machined, ground, and drilled prior to oil-hardening heat treatment. The 18-inch length is a standard cut appropriate for bench-scale toolmaking projects. Edge squareness is held to 0.003 inches per inch across all edges, supporting accurate layout and setup work.

Key Features

• AISI Type O1 oil-hardening tool steel for reliable hardening response with minimal distortion
• Thickness tolerance of +/- 0.001 inches for precise pre-machined fit
• Width tolerance of 0.0000 to -0.005 inches for consistent stock width
• Length tolerance of +0.250 inches ensures full usable length
• Edge squareness held to 0.003 inches per inch on all edges
• Supplied in annealed condition for full machinability before heat treat

Compatibility

Designed as a standard AISI O1 oil-hardening tool steel flat stock suitable for general toolmaking, die work, and precision fabrication applications where O1 grade material is specified.

Installation Notes

Handle and machine this stock in the annealed condition using standard toolmaking practices. Heat treatment to final hardness should be performed by a qualified tool and die maker or heat treat facility following AISI O1 oil-quench procedures. Use appropriate personal protective equipment when cutting, grinding, or handling tool steel stock. Inspect dimensions against print tolerances prior to machining to account for stock tolerances.