Vlier S59 Threaded Spring Plunger 3/8-16 Steel

Product Description

The VLIER S59 is a standard threaded spring plunger designed to provide controlled positioning, indexing, and light-duty detent functions in mechanical assemblies. The S59 features a 3/8-16 thread with a 1-1/8 inch thread length and a steel body and nose, making it well-suited for demanding industrial and machine-tool applications. The plunger tip diameter ranges from 0.186 to 0.187 inches with a 3/16 inch projection, delivering an initial end force of 2.8 pounds and a final end force of 7.2 pounds. This part is installed by machinists, maintenance technicians, and mechanical assembly professionals.

The S59 is used in applications where a spring-loaded plunger is threaded directly into a tapped hole to index, locate, or retain a moving component. Typical install scenarios include jigs, fixtures, tooling plates, sliding panels, and equipment housings in both light manufacturing and industrial settings. The standard plunger length type and no locking element make this a straightforward drop-in for new builds or replacements in assemblies requiring repeatable, low-force detent action.

Key Features

• 3/8-16 thread with 1-1/8 inch thread length for direct installation into standard tapped holes
• Steel body and steel nose for durability in industrial environments
• 2.8 pound initial end force and 7.2 pound final end force for consistent detent performance
• Plunger tip diameter 0.186 to 0.187 inches with 3/16 inch projection
• No locking element - standard thread engagement without thread-lock feature
• Standard plunger length type for use in conventional tapped-hole configurations

Compatibility

Designed as an OEM-style replacement or new-install threaded spring plunger for mechanical assemblies using a 3/8-16 tapped hole requiring a standard-projection steel plunger.

Installation Notes

Installation is performed by machinists or mechanical assembly technicians using a standard hex wrench or spanner tool sized for the 3/8-16 body. De-energize and lock out any equipment before servicing assemblies containing spring plungers. Thread the S59 into the tapped hole to the desired depth to achieve the required end force; do not overtighten, as this can restrict plunger travel or damage the spring mechanism. Confirm plunger projection and force meet the assembly specification before returning equipment to service.