Spi 13-280-3 Combination Square Set 24 in 4 Piece

Product Description

The SPI 13-280-3 is a 4-piece combination square set built for precision layout and inspection work on the job site or in the shop. The set includes a 24-inch hardened steel blade graduated in 4R style, covering increments of 1/64, 1/32, 1/16, and 1/8 inch. Three interchangeable cast iron heads — a square head, a center head, and a protractor head — mount to the blade for a full range of layout tasks. At 3.85 pounds, the set is substantial enough for stable use without being awkward to handle. Machinists, pipefitters, fabricators, and tool-and-die professionals reach for this set when layout accuracy cannot be compromised.

This combination square set is suited to metal fabrication shops, machine shops, pipefitting, and general industrial layout work. The 24-inch blade length makes it practical for larger workpieces where a shorter rule would fall short. The three head types cover right-angle transfer, centerline scribing on round stock, and angle measurement up to 180 degrees, making the set versatile enough to replace several individual layout tools in a single kit.

Key Features

• 24-inch hardened steel blade for durability and long-term graduation legibility
• 4R graduation style: 1/64, 1/32, 1/16, and 1/8 inch increments on a single blade
• Cast iron square head, center head, and protractor head included
• Three-head configuration covers right-angle, centerline, and angle layout tasks
• Set weight of 3.85 pounds provides stable, balanced feel during use

Compatibility

Designed as a standard 4-piece combination square set for use with conventional interchangeable-head layout systems accepting a 24-inch graduated steel blade.

Installation Notes

Combination square sets require no installation but should be verified for square accuracy before use on critical layout work. Store the blade and heads separately to prevent nicking the graduated surface. Handle cast iron heads with care to avoid chips or cracks from impact. Periodic cleaning of the blade channel and tightening of the locking hardware maintains measurement consistency over time.