Spi 13-232-4 Steel Parallel Set 12x1x0.75 in Matched Pair

Product Description

The SPI 13-232-4 is a high-grade hardened tool steel parallel set sold as a matched pair. Measuring 12 inches long, 1 inch high, and 0.75 inches thick, each parallel features four precision-ground faces with a parallelism tolerance of 0.0003 inches and a squareness tolerance of 0.0005 inches. Hardened to 50 Rc, these parallels are designed for use in machine shop and toolroom environments where accurate workpiece support and setup precision are required. Machinists, toolmakers, and precision metrology technicians are the primary users of this product.

These parallels are suited for use on milling machines, surface grinders, and inspection plates where consistent workholding height and tight geometric tolerances are critical. The matched-pair configuration ensures interchangeability between the two pieces, supporting repeatable setups. Typical applications include supporting workpieces during vise clamping, establishing reference datums, and checking parallelism of machined surfaces. Both industrial and toolroom environments benefit from the four-face ground design, which allows any face to serve as a reference surface.

Key Features

• Parallelism tolerance of 0.0003 inches across all four precision-ground faces
• Squareness tolerance of 0.0005 inches for reliable geometric reference
• Hardened steel construction at 50 Rc for wear resistance and long service life
• Four-face parallel type — any face usable as a reference surface
• Sold as a matched pair for consistent, interchangeable setups
• High-grade hardened tool steel material throughout

Compatibility

Designed as a general-purpose precision parallel set compatible with standard milling vises, surface grinder magnetic chucks, and inspection surface plates used in machine shop and toolroom applications.

Installation Notes

These parallels are a setup and workholding accessory, not a permanently installed component. Clean all mating surfaces before use to prevent contamination from chips or coolant from affecting setup accuracy. Handle with care to avoid nicks or burrs on the ground faces, which would compromise tolerance integrity. Store in a protective case or with separators to maintain surface condition between uses.