Starrett 51445 Four Face Parallel 6in Tool Steel Matched Pair

Product Description

The STARRETT 51445 is a four face parallel manufactured from a special grade of tool steel, sold as a matched pair. Each parallel measures 6 inches long by 1 inch high by 0.125 inch thick and is accurately ground on all four faces to close dimensional limits. Squareness tolerance is held to 0.0005 inches per 1 inch, making these parallels suitable for precision setup and inspection work in machine shops and toolrooms. Machinists, toolmakers, and metrology technicians use these to establish reference surfaces, support workpieces in vises, and verify squareness during layout and grinding operations.

Four face parallels are a standard toolroom item used in milling, surface grinding, and precision layout applications. The matched-pair format ensures both pieces maintain consistent height and thickness, which is critical when supporting workpieces symmetrically across a vise or fixture. At 6 inches long with a 1-inch height and 0.125-inch thickness, this size fits common benchtop vises and smaller surface grinder setups. The close-tolerance ground surfaces provide reliable contact without rocking or introducing error into setups.

Key Features

• All four faces accurately ground to close limits for reliable reference surfaces
• Squareness tolerance of 0.0005 inches per 1 inch
• Manufactured from a special grade of tool steel for durability and wear resistance
• Sold as a matched pair for symmetrical workpiece support
• Compact 0.125-inch thickness fits tight vise setups and narrow fixture slots

Compatibility

Designed as a standard toolroom parallel suitable for use with bench vises, milling vises, and surface grinder setups requiring a 6-inch parallel with 1-inch height and 0.125-inch thickness.

Installation Notes

Parallels should be handled with clean, dry hands or cotton gloves to prevent corrosion from skin oils. Inspect contact surfaces for burrs or nicks before use, and stone lightly if needed to maintain flatness. Store in a protective case or wrap in oiled cloth when not in use to prevent rust. No power source is required, but always secure the workpiece fully before beginning any machining operation.