Spi 13-458-5 Combination Square Blade 18 Inch

Product Description

The SPI 13-458-5 is an 18-inch replacement blade for combination squares, graduated in both English and metric units. The blade carries dual-scale markings at 1/64-inch, 1/32-inch, 0.5 mm, and 1 mm increments, making it suitable for precision layout work across measurement systems. A baked enamel coating protects the graduation marks from wear and corrosion in shop environments. The blade weighs 0.5 pounds and is designed as a direct replacement or spare for standard combination square heads used in machining, fabrication, and general trade work.

This blade is used in metalworking shops, fabrication facilities, machine shops, and trade environments where both imperial and metric layout work is performed on the same job. It is commonly installed into combination square heads to restore a worn or damaged blade without replacing the entire tool. Machinists, pipefitters, and sheet metal workers are the primary users. The dual-graduation format is especially useful on jobs that bridge metric drawings and imperial field measurements.

Key Features

• 18-inch blade length for extended layout and scribing reach
• English graduations at 1/64 inch and 1/32 inch increments
• Metric graduations at 0.5 mm and 1 mm increments
• Baked enamel coating protects graduation marks from shop wear and moisture
• Dual-scale format eliminates the need to switch blades between measurement systems

Compatibility

Designed as a replacement blade for standard combination square heads that accept 18-inch blades with English and metric graduation.

Installation Notes

Installation is performed by a machinist or layout technician using the locking screw or clamp mechanism on the combination square head. Ensure the head lock is fully released before sliding the blade in or out to avoid scratching the graduation markings. Verify blade seating and square alignment with a known reference surface before returning the tool to service.