Starrett 51438 Square Straight Edge 12 in Steel

Product Description

The STARRETT 51438 is a square straight edge precision layout and inspection tool designed for machinists, toolmakers, and metrology professionals who require verified flatness and parallelism in their work. Manufactured from steel, this straight edge measures 12 inches long, 1-13/32 inches wide, and 11/64 inches thick. It holds an edge flatness tolerance of 0.0004 inches and a parallelism tolerance of 0.0004 inches, making it suitable for surface plate work, layout inspection, and checking the accuracy of machined surfaces.

This straight edge is used in precision machining, tool and die, quality control, and general metrology applications. It is appropriate for both shop floor and inspection room environments where close-tolerance verification of flat surfaces, edges, and part geometry is required. The compact 12-inch length suits bench-scale work and fits standard surface plates without overhang.

Key Features

• Edge flatness of 0.0004 inches for precision inspection and layout tasks
• Parallelism tolerance of 0.0004 inches ensures consistent reference across both edges
• Steel construction for durability and dimensional stability
• 12-inch length suits a wide range of bench-scale and surface plate applications
• Square edge type provides a defined, consistent reference profile

Compatibility

Designed as a general-purpose precision straight edge for use in machine shops, tool rooms, and inspection environments requiring close-tolerance flatness verification.

Installation Notes

This tool requires no installation. Handle with clean dry hands or cotton inspection gloves to prevent corrosion from skin oils. Store flat or in a protective case to maintain edge accuracy. Do not use as a cutting guide or apply lateral force that could induce a bend or nick the reference edge.