Spi 13-205-0 Steel Parallel Set 6x1.5x0.5 Inch Precision Ground

Product Description

The SPI 13-205-0 is a matched pair of precision-ground steel parallels designed for use in machining, grinding, and inspection setups. Each parallel measures 6 inches long, 1-1/2 inches high, and 1/2 inch thick, with all four faces ground to a parallelism tolerance of 0.0003 inches and a squareness tolerance of 0.0005 inches. Manufactured from high-grade hardened tool steel at 50 Rc hardness, these parallels provide stable, repeatable workpiece support in milling vises, surface grinders, and layout applications. Machinists, toolmakers, and quality technicians rely on this level of ground accuracy for precision fixturing and part inspection.

This matched pair is suited for use in job shops, tool rooms, and manufacturing environments where consistent workpiece elevation and alignment are critical. The four-face precision-ground construction allows any face to be used as a reference surface, giving flexibility in tight setup situations. Typical applications include elevating workpieces in vises for milling operations, supporting parts during surface grinding, and serving as reference blocks during quality inspection on surface plates.

Key Features

• Matched pair sold together for consistent, verified tolerance across both parallels
• Parallelism tolerance of 0.0003 inches across all four precision-ground faces
• Squareness tolerance of 0.0005 inches for reliable right-angle reference
• High-grade hardened tool steel construction at 50 Rc for wear resistance and long service life
• Four-face ground design allows any face to serve as a seating or reference surface
• Compact 1/2-inch thickness suits narrow vise setups and close-tolerance fixturing

Compatibility

Designed as a general-purpose precision parallel set compatible with standard milling vises, surface grinders, and inspection surface plates where 6-inch length and 1-1/2-inch height parallels are required.

Installation Notes

Parallels should be cleaned of chips, coolant, and debris before each use to ensure accurate seating. Handle with care to avoid nicking ground surfaces, as surface damage degrades reference accuracy. Store in a protective case or on a clean surface away from other tooling to prevent corrosion and surface wear. Periodic inspection of ground faces against a calibrated surface plate is recommended to confirm tolerance is maintained over time.