Vlier SCH347 Thumb Screw 1/2-13 Knurled Head Steel

Product Description

The VLIER SCH347 is a steel thumb screw designed for tool-free manual adjustment and clamping applications in industrial and mechanical assembly work. It features a knurled head for positive finger grip and a swivel pad tip that pivots up to 7.5 degrees, allowing the tip to seat flush against angled or irregular surfaces without marring the workpiece. The 1/2-13 UNC thread is a common coarse-pitch standard suited to steel fixtures and tooling plates. A black oxide finish provides mild corrosion resistance and reduces light glare on the fastener head. This part is typically installed and adjusted by machinists, toolmakers, and maintenance technicians.

The SCH347 fits applications where repeatable manual clamping or positioning is required without tools. Common use cases include jig and fixture building, machine tool setups, and workholding systems in manufacturing environments. The swivel pad tip design is especially useful when clamping against surfaces that are not perfectly perpendicular to the screw axis. No shoulder is present on this version, making it appropriate for direct thread-through mounting without a locating register.

Key Features

• 1/2-13 UNC coarse thread for broad compatibility with standard tapped steel fixtures
• Knurled head, 1.25 inches in diameter, for secure finger tightening without tools
• Swivel pad tip with 7.5-degree pivot range accommodates angled clamping surfaces
• Black oxide finish for mild corrosion resistance and low-glare appearance
• Without-shoulder design for direct thread-through mounting
• Manufactured to ISO 9001 quality standards

Compatibility

Designed as a standard 1/2-13 UNC thumb screw for use in jigs, fixtures, tooling plates, and other workholding or positioning assemblies that accept a 1/2-13 tapped hole.

Installation Notes

Installation and adjustment are typically performed by hand; no wrench is required or recommended for standard clamping torque. Ensure the mating tapped hole is clean and free of debris before threading in the screw. Power down or lock out any machinery before adjusting fixturing screws during setup changes. Do not exceed the manual clamping force appropriate for the application, as overtightening by hand is generally self-limiting but can damage soft workpieces.