Spi 98-459-1 Steel Parallel Set 6x1.5x0.125 in

Product Description

The SPI 98-459-1 is a matched pair of high-grade hardened steel parallels used to support and level workpieces during machining, grinding, and inspection operations. Each parallel measures 6 inches long, 1-1/2 inches high, and 1/8 inch thick, with all four faces precision ground for accuracy. Squareness tolerance is held to 0.0005 inches per 1 inch, making these suitable for demanding setups where consistency between matched pairs is critical. Hardness is rated at 50 Rc, providing resistance to wear and deformation under repeated use in machine shop environments.

These parallels are intended for use in machine shops, tool rooms, and precision manufacturing settings. Machinists, toolmakers, and quality technicians use matched parallel sets to establish reference datums, support workpieces in vises or on surface plates, and ensure consistent part presentation during milling, boring, and grinding operations. The four-face ground design means any face can serve as a reference surface, adding versatility to the pair across multiple setup configurations.

Key Features

• Matched pair — both pieces held to consistent dimensions for symmetrical setups
• All four faces precision ground to 0.0005 inches per 1 inch squareness tolerance
• High-grade hardened steel at 50 Rc for wear resistance and long service life
• 6 inch length provides stable support across a wide range of workpiece sizes
• 1/8 inch thickness suits narrow vise jaws and tight clearance setups

Compatibility

Designed as a general-purpose matched parallel set suitable for use with standard machine vises, surface plates, and inspection fixtures commonly found in milling, grinding, and toolroom applications.

Installation Notes

Parallels are hand-placed into machine vises or onto surface plates by machinists and toolmakers — no mechanical installation is required. Clean all mating surfaces before use to prevent chips or debris from affecting part seating and measurement accuracy. Avoid dropping or striking the parallels, as impact can alter ground surfaces or affect hardness integrity. Store in a protective case or dedicated holder to preserve ground faces between uses.