Vlier D56 Threaded Ball Plunger 5/16-18 Delrin Body

Product Description

The VLIER D56 is a threaded ball plunger designed for controlled end-force applications in mechanical assemblies, fixtures, and positioning systems. The body is machined from Delrin, a durable acetal resin known for low friction and chemical resistance, while the ball is stainless steel for corrosion resistance and wear durability. The D56 uses a 5/16-18 thread for straightforward installation into tapped holes. With an initial end force of 4 pounds and a final end force of 9 pounds, the D56 delivers predictable, repeatable detent or indexing force across its 0.039-inch maximum ball reach. The ball diameter measures 0.156 inches and the body length is 0.578 inches.

Threaded ball plungers like the D56 are commonly used in industrial and mechanical applications including jig and fixture work, tooling alignment, panel latching, and light-duty detent positioning. The controlled end-force specification makes this plunger suitable wherever consistent spring-loaded ball engagement is required without relying on a locking element. It is installed by machinists, tool and die makers, and maintenance technicians working on mechanical assemblies that require repeatable indexing or registration points.

Key Features

• 5/16-18 thread for installation into standard tapped holes
• Delrin body offers low friction, chemical resistance, and lightweight construction
• Stainless steel ball provides corrosion resistance and long-term wear durability
• Controlled end force: 4 pounds initial, 9 pounds final
• Maximum ball reach of 0.039 inches for precise detent engagement
• No locking element - allows for tool-free adjustment or removal
• Color code: Purple for quick identification in multi-plunger assemblies

Compatibility

Designed for use in any application requiring a 5/16-18 threaded ball plunger with controlled end force. Typical fitment includes jigs, fixtures, tooling plates, and mechanical assemblies with a corresponding 5/16-18 tapped mounting hole.

Installation Notes

Installation requires a tapped 5/16-18 hole at the desired engagement point. Thread the plunger body in by hand and use an appropriate wrench or driver to set final depth - do not overtighten, as the Delrin body can be damaged by excessive torque. Ensure the mating surface is clean and the ball travel path is clear of debris before final assembly. No special tools or codes are required for standard bench or fixture installation.