Fowler 52-439-031-0 1-2-3 Setup Block Hardened Steel

Product Description

The FOWLER 52-439-031-0 is a hardened steel 1-2-3 setup block matched pair used for workholding, layout work, and precision grinding setups in machine shops and tool rooms. Each block measures 1 inch wide, 2 inches long, and 3 inches tall and is ground to an overall tolerance of 0.0002 inches. Squareness is held to 0.0003 inches, and parallelism is held to 0.0002 inches. The blocks are hardened to 58-60 HRC for long-term dimensional stability. Thirty-one tapped holes in 5/16-18 thread are distributed across the block faces to accept clamps, studs, and other fixturing hardware.

These setup blocks are used in milling, drilling, and grinding operations where a precise, square reference surface is required. They are a standard fixture on surface plates, sine plates, and machine tool tables. Common applications include raising workpieces off a table surface, squaring a vise or fixture, and supporting parts during layout and inspection. The matched pair configuration ensures both blocks are held to the same dimensional tolerances, making them interchangeable in stacked or paired setups.

Key Features

• 1-2-3 block format: 1 inch wide, 2 inches long, 3 inches tall for versatile fixturing orientations
• Overall tolerance of 0.0002 inches for precision workholding and layout
• Squareness held to 0.0003 inches across all faces
• Parallelism held to 0.0002 inches
• 31 tapped 5/16-18 holes for clamping studs and fixturing hardware
• 58-60 HRC hardened steel construction for dimensional stability and wear resistance
• Sold as a matched pair with consistent tolerances between both blocks

Compatibility

Designed as a standard 1-2-3 setup block pair suitable for use on surface plates, milling machine tables, drill press tables, and surface grinders wherever a square, hardened reference block is required.

Installation Notes

Setup blocks are placed and positioned by machinists and toolroom technicians. Clean all mating surfaces before use to prevent chips or debris from affecting seating accuracy. Inspect blocks periodically for nicks or burrs on ground faces, and dress minor surface damage with a hard Arkansas stone before use. Store blocks protected from moisture to prevent corrosion on the ground surfaces.