Gibraltar 831712-G Shoulder Screw 3/4 in Black Oxide Steel

Product Description

The GIBRALTAR 831712-G is a steel shoulder screw with a 0.75-inch shoulder diameter and a 1.25-inch shoulder length. The shoulder provides a precise, ground bearing surface that acts as a fixed pivot or spacer in mechanical assemblies, jigs, fixtures, and linkage systems. Machined from 1137 steel and finished in black oxide for mild corrosion resistance, this screw drives with a 3/8-inch hex socket and threads in at 5/8-11 UNC. The 1-inch head diameter and 0.5-inch head height deliver a broad clamping face suited to high-load applications common in industrial and trade settings.

Shoulder screws of this size are typically used in heavy-duty mechanical fixtures, tooling plates, and pivot assemblies where a precise-diameter unthreaded shank is required to control bearing fit or guide moving components. The 5/8-11 UNC thread is a coarse-pitch standard sizing that engages readily in tapped steel and cast iron. This fastener is appropriate for machine shops, maintenance trades, and field technicians building or servicing mechanical subassemblies that demand accurate positional control between mating parts.

Key Features

• 0.75-inch shoulder diameter with 0.7500-inch decimal tolerance for precise bearing and bushing fits
• 1.25-inch shoulder length provides a full bearing surface for pivoting or sliding components
• 5/8-11 UNC thread standard ensures compatibility with standard tapped holes in steel and cast iron
• Black oxide finish provides mild corrosion resistance and reduces light reflection in tooling environments
• 3/8-inch hex socket drive accepts standard hex keys and socket drivers for installation in confined spaces
• 1137 steel material grade offers good machinability and strength for medium-to-heavy load applications

Compatibility

Designed as an OEM-style and aftermarket replacement shoulder screw for mechanical assemblies, jigs, and fixtures requiring a 0.75-inch shoulder diameter, 1.25-inch shoulder length, and 5/8-11 UNC thread.

Installation Notes

Installation is performed by machinists, millwrights, or maintenance technicians using a 3/8-inch hex key or hex socket driver. De-energize or lock out any equipment before removing or installing fasteners in live assemblies. Thread engagement should be verified against the tapped hole depth to avoid bottoming out the thread before the shoulder seats fully. Do not use impact drivers at full torque on shoulder screws, as this can damage the precision shoulder surface.