Starrett 51447 Four Face Tool Steel Parallel 6x7/8x3/16 in

Product Description

The STARRETT 51447 is a four face tool steel parallel sold as a matched pair, designed for precision setup and workholding applications in machine shops and tool rooms. Measuring 6 inches long, 7/8 inches high, and 3/16 inches thick, this parallel is precision ground on all four sides to close tolerances. Manufactured from a special grade of tool steel, it delivers the dimensional consistency and squareness required for accurate part location, surface plate work, and milling setups. Installation and use are performed by machinists, toolmakers, and precision metrology technicians.

Four face parallels are used in milling, grinding, and inspection setups where a part must be elevated and precisely referenced off a flat surface. The matched pair configuration ensures both pieces are ground to the same dimensions, allowing them to be used together when both sides of a workpiece need consistent support. Typical applications include vise setups on vertical mills, surface grinder workholding, and layout work on surface plates in both production and toolroom environments.

Key Features

• All four sides precision ground to close limits for accurate referencing on any face
• Manufactured from a special grade of tool steel for rigidity and wear resistance
• Squareness tolerance of 0.0005 inches per 1 inch ensures reliable setup accuracy
• Sold as a matched pair for consistent dual-side workpiece support
• Compact 3/16 inch thickness suits tight vise and fixture clearances

Compatibility

Designed as a standard four face parallel for use in milling vises, surface grinders, and precision layout setups where a matched pair of tool steel parallels is required.

Installation Notes

Parallels are a non-powered precision tool and require no electrical isolation or fluid shutoff before use. Clean the contact surfaces of both the parallel and the workholding device before placement to prevent measurement error caused by chips or debris. Do not use parallels as striking tools or pry bars, as impact can affect ground surface accuracy. Periodic cleaning and light oiling will protect the tool steel surfaces from corrosion during storage.