Starrett 54143 O1 Tool Steel Flat Stock 7/16x2-1/2x18 in

Product Description

The STARRETT 54143 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die making, and precision machining applications. Manufactured to AISI Type O1 specification, this flat bar measures 7/16 inches thick, 2-1/2 inches wide, and 18 inches long, with a weight of 5.58 pounds. Thickness tolerance is held to plus or minus 0.001 inches, giving machinists and toolmakers a reliable starting dimension before heat treat and finish grinding. O1 tool steel offers good machinability in the annealed state and responds well to oil quench hardening, making it a standard choice for punches, dies, gauges, and cutting tools.

This flat stock is suited for job shops, toolrooms, and maintenance departments that fabricate or repair tooling components. The 18-inch length provides practical stock for blanking out multiple tool profiles or a single longer workpiece. The 7/16 by 2-1/2 inch cross section covers a wide range of flat die and punch plate applications. Machinists working in both production and prototype environments will find this bar appropriate for projects requiring tight dimensional control before hardening.

Key Features

• AISI Type O1 oil-hardening tool steel — good machinability and wear resistance after heat treatment
• Thickness tolerance of plus or minus 0.001 inches for precise stock removal planning
• Width tolerance of 0.000 to minus 0.005 inches
• Length tolerance of plus 0.250 inches
• Edge squareness held to 0.003 inches per inch on all edges
• Ready-to-machine annealed condition flat bar

Compatibility

Designed as standard O1 tool steel flat stock for use in toolmaking, die making, punch fabrication, and general precision machining applications requiring oil-hardening tool steel material.

Installation Notes

Cutting and machining of tool steel flat stock is typically performed by machinists or toolmakers using milling machines, surface grinders, band saws, and EDM equipment. Secure the workpiece firmly before any machining operation. Heat treatment, including hardening and tempering of O1 tool steel, should be performed by qualified personnel following established metallurgical procedures and applicable shop safety protocols. Always wear appropriate PPE when cutting, grinding, or handling tool steel stock.