Gibraltar 831407-G Shoulder Screw 3/8 in Black Oxide Steel

Product Description

The GIBRALTAR 831407-G is a black oxide steel shoulder screw designed for precision fastening applications where a controlled-diameter bearing surface is required. The 3/8-inch shoulder diameter and 3/4-inch shoulder length provide an accurate pivot or guide pin surface for linkages, jigs, fixtures, and mechanical assemblies. The 5/16-18 UNC threaded shank anchors the screw securely into tapped holes. Drive engagement is via a 3/16-inch hex socket, allowing installation with a standard hex key or Allen-head driver. Material grade 1137 steel with a black oxide finish provides corrosion resistance and a clean appearance. This fastener is installed by machinists, maintenance technicians, and mechanical assemblers across industrial and trade applications.

This shoulder screw is suited for use in jigs, fixtures, conveyor components, linkage assemblies, and equipment where a hardened, precision shoulder is needed to guide or retain moving parts. The black oxide finish makes it appropriate for indoor mechanical environments where moderate corrosion resistance is acceptable. Sold individually with a minimum order quantity of 2 units, it fits applications requiring accurate fit between the shoulder and a reamed or drilled clearance hole.

Key Features

• 3/8-inch shoulder diameter provides a precise bearing and guide surface
• 3/4-inch shoulder length suits standard-depth linkage and fixture applications
• 5/16-18 UNC thread for secure engagement in standard tapped holes
• 3/16-inch hex socket drive for installation with common hex keys
• Material grade 1137 steel for strength in mechanical fastening use
• Black oxide finish for mild corrosion resistance and reduced light reflection

Compatibility

Designed as a standard shoulder screw for use in jigs, fixtures, and mechanical assemblies requiring a 3/8-inch shoulder diameter, 3/4-inch shoulder length, and 5/16-18 UNC thread engagement.

Installation Notes

Installation is performed by machinists or maintenance technicians using a 3/16-inch hex key or Allen-head driver. De-energize or lock out equipment fully before replacing or installing shoulder screws in active machinery per applicable OSHA lockout/tagout procedures. The clearance hole receiving the shoulder should be sized to match the 0.3750-inch shoulder diameter for proper fit and function. Do not overtighten the threaded shank, as shoulder screws are designed to clamp at the head face, not to be torqued beyond snug contact with the mating surface.