Holo-krome 08138 Shoulder Screw 3/4 in Alloy Steel Hex Socket

Product Description

The HOLO-KROME 08138 is a hex socket shoulder screw manufactured from Grade 8 alloy steel for use in precision mechanical assemblies, jigs, fixtures, and tooling applications. The shoulder measures 3/4 inch in diameter and 3 inches in length, providing a precision bearing surface for rotating or sliding components. A 5/8-11 UNRC thread with a 7/8-inch thread length secures the fastener in place. The rounded head is 1 inch in diameter and 1/2 inch tall, driven by a 3/8-inch hex socket drive. Overall length is 4-3/8 inches. This fastener is installed by machinists, tool-and-die workers, and maintenance technicians in industrial environments.

Shoulder screws of this type are used wherever a precise, hardened shaft is needed to act as a pivot, guide, or bearing journal. Common applications include die sets, stripper plates, cams, linkages, and fixture locating pins. The 3/4-inch shoulder diameter suits medium-to-heavy-duty tooling setups. The uncoated finish maintains dimensional accuracy to specification. This fastener ships as a single unit and is suitable for both OEM production builds and maintenance replacement use.

Key Features

• 3/4-inch shoulder diameter with 3-inch shoulder length provides a reliable precision bearing surface
• Grade 8 alloy steel construction for high strength and wear resistance
• 5/8-11 UNRC threaded end with 7/8-inch thread length for secure fastening
• 3/8-inch hex socket drive with rounded head for recessed installation
• Uncoated finish maintains tight dimensional tolerances
• Meets ASME B1.1 and ASME B18.3 standards

Compatibility

Designed as a standard shoulder screw per ASME B18.3 for use in precision tooling, fixture, and mechanical assembly applications requiring a 3/4-inch shoulder diameter bearing surface with a 5/8-11 thread.

Installation Notes

Installation is performed by machinists or maintenance technicians using a 3/8-inch hex key or socket driver. Ensure the mating bore is dimensionally matched to the 3/4-inch shoulder for proper fit and function. De-energize and lock out all machinery before replacing or installing shoulder screws in active assemblies. Do not overtighten beyond the thread engagement length, as the shoulder must seat fully to function as intended.