Vlier S55A Threaded Spring Plunger 1/4-28 1 in Thread

Product Description

The VLIER S55A is a standard threaded spring plunger designed to provide controlled, spring-loaded positioning and retention in precision assemblies. Featuring a 1/4-28 thread with a 1 inch thread length, the S55A delivers 1 pound of initial end force and 4 pounds of final end force through a steel nose and steel body. The plunger projection measures 3/16 inch, with a plunger diameter ranging from 0.117 to 0.118 inches. This part is typically installed by machinists, toolmakers, and mechanical assembly technicians working in jigs, fixtures, indexing mechanisms, and positioning applications.

The S55A fits installations requiring a compact, fine-thread spring plunger in steel construction. Common applications include fixture plates, machine tool components, dial mechanisms, and precision indexing assemblies where repeatable low-to-moderate spring force is needed. The standard plunger length type makes this a straightforward drop-in choice for general-purpose positioning work in both production and toolroom environments. No locking element is present, which simplifies installation and removal in applications where adjustment is routine.

Key Features

• 1/4-28 fine thread for precise, low-clearance installation
• 1 inch thread length and 1 inch body length for consistent engagement depth
• 3/16 inch plunger projection suitable for standard detent and positioning tasks
• 1 pound initial end force and 4 pound final end force for controlled spring resistance
• Steel nose and steel body construction for durability in industrial environments
• No locking element - allows straightforward torque-in installation and future adjustment

Compatibility

Designed as an OEM-style replacement or standard installation component for fixtures, jigs, and mechanical assemblies requiring a 1/4-28 threaded spring plunger with a standard plunger length configuration.

Installation Notes

Installation is typically performed by machinists or mechanical assembly technicians using a hex wrench or screwdriver appropriate for the body drive style. Ensure the mating threaded bore is clean and free of debris before threading in the plunger. Do not overtighten, as this can restrict plunger travel and reduce spring performance. Verify plunger projection and spring force requirements against the assembly specification before final installation.