Starrett 50097 Combination Square Blade 36 in 4R

Product Description

The STARRETT 50097 is a 36-inch replacement blade for combination squares, graduated in the 4R style with four graduation increments: 1/64, 1/32, 1/16, and 1/8 inch. Manufactured from steel with a satin chrome finish, the blade measures 1 inch wide and 0.09 inches thick. It is designed for precision layout and measurement work in mechanical, fabrication, plumbing, and general trade applications. Machinists, pipefitters, sheet metal workers, and experienced tradespeople rely on combination square blades for scribing, depth measurement, and checking squareness on flat stock, pipe, and structural components.

This blade is suited for shop and field use wherever a full 36-inch measuring reference is needed. The 4R graduation pattern provides four scales along the blade face, giving the installer or layout tech multiple increment options without switching tools. The satin chrome finish reduces glare under work lighting and resists corrosion in typical shop environments. It is appropriate for residential and commercial construction, fabrication shops, and mechanical service work requiring accurate long-length layout.

Key Features

• 36-inch blade length for long-reach layout and measurement tasks
• 4R graduation style with four scales: 1/64, 1/32, 1/16, and 1/8 inch increments
• Steel construction provides rigidity and durability under repeated use
• Satin chrome finish minimizes glare and resists surface corrosion
• 1-inch blade width with 0.09-inch thickness for stable, flat contact on work surfaces

Compatibility

Designed as an OEM-style replacement blade for standard combination square heads that accept a 36-inch graduated blade. Verify head slot width and locking mechanism compatibility before installation.

Installation Notes

Blade replacement on a combination square typically requires loosening the locking nut or thumb screw on the square head and sliding the existing blade free from the groove. Slide the new blade into the head groove, confirm graduation markings face the correct direction for the intended use, and retighten the locking fastener securely before measuring. No power tools or electrical shutoffs are required for this task. Handle blade edges carefully, as the steel edges can cause cuts during installation.