Jergens 30870 Threaded Spring Plunger M4 X 0.7 Steel

Product Description

The JERGENS 30870 is a threaded spring plunger designed to provide controlled, spring-loaded positioning and indexing in light-duty mechanical assemblies. The body is steel with a black finish and measures 16 mm in length, threading directly into an M4 x 0.7 tapped hole. The Delrin nose tip offers a low-friction, non-marring contact point with a maximum diameter of 1.78 mm and a projection of 2.5 mm. Initial end force is 0.32 kg, rising to a final end force of 1.04 kg at full compression. A 2 mm hex drive allows for easy installation and removal with standard hex key tooling.

This spring plunger is suited for use in fixtures, jigs, tooling plates, and precision mechanical assemblies where repeatable part positioning or detent action is required. Its compact M4 thread size makes it appropriate for light-duty applications in tight spaces. The Delrin nose protects finished or soft workpiece surfaces from marking during contact. Machinists, toolmakers, and mechanical assembly technicians commonly install this type of component in production fixtures and workholding setups.

Key Features

• M4 x 0.7 thread for direct installation into standard tapped holes
• Steel body with black finish for corrosion resistance in shop environments
• Delrin nose tip provides non-marring, low-friction contact
• 2 mm hex drive for precise installation torque control with a hex key
• 2.5 mm plunger projection with a force range of 0.32 kg to 1.04 kg
• No locking element, allowing free spring action without thread-lock features

Compatibility

Designed as a standard OEM-style threaded spring plunger for use in any application requiring an M4 x 0.7 tapped hole and light-duty spring-loaded positioning or detent function.

Installation Notes

Installation is performed by threading the plunger into a pre-tapped M4 x 0.7 hole using a 2 mm hex key. Ensure the mating hole is clean and free of chips or debris before installation. De-energize or immobilize any moving assemblies before servicing spring plungers in active fixtures. Do not exceed the rated end force by over-compressing the plunger, as this may damage the nose tip or spring.