Vlier M56 Threaded Spring Plunger 5/16-18 Steel Stubby

Product Description

The VLIER M56 is a stubby threaded spring plunger designed for applications requiring high end force in restricted or tight-clearance spaces. It features a 5/16-18 thread with a 0.562-inch thread length and a 0.135-inch maximum plunger diameter. The steel body and steel nose deliver durability in demanding mechanical assemblies. Initial end force is 3.75 pounds and final end force reaches 15.5 pounds, making it well suited for positive positioning and detent functions where consistent spring resistance is critical. This type of component is typically installed by mechanical assemblers, toolmakers, or maintenance technicians working on jigs, fixtures, machine tools, and precision mechanical assemblies.

The M56 is intended for use in high-force, space-constrained installations. Its stubby profile makes it practical in locations where standard-length plungers cannot fit. Typical applications include positioning mechanisms, assembly fixtures, and tooling components where the plunger must resist movement under load without occupying significant axial depth. The absence of a locking element means the plunger is pressed in by thread engagement only, keeping installation straightforward in most standard tapped holes.

Key Features

• Stubby plunger profile suited for restricted-space installations
• High final end force of 15.5 pounds for positive detent and positioning
• 5/16-18 thread for compatibility with standard tapped holes
• Steel body and steel nose for mechanical durability
• No locking element for straightforward thread-in installation
• Compact 0.084-inch plunger projection minimizes protrusion

Compatibility

Designed as a threaded spring plunger for standard 5/16-18 tapped holes in mechanical assemblies, jigs, fixtures, and tooling where high end force and restricted axial space are required.

Installation Notes

Install using a standard hex key or spanner appropriate to the body hex size into a clean, properly tapped 5/16-18 hole. Ensure the mating component is de-energized or fully stopped before servicing any spring plunger in a live assembly. Avoid over-torquing, which can deform the body or alter spring preload characteristics. Inspect the thread engagement depth to confirm the plunger projection is not obstructed at full compression.