Steel Indexing Plungers – Blackened Non-Lock-Out Spring Return

Steel Indexing Plungers – Blackened Non-Lock-Out Spring Return

Carbon Steel Body | Blackened Surface Finish | Spring-Loaded Locating Pin | M6, M8 & M10

Juxin Fasteners supplies blackened steel indexing plungers with non-lock-out spring-return mechanisms for industrial machinery, automation equipment, 

manufacturing fixtures and mechanical positioning systems.

Manufactured with a carbon steel threaded body and blackened surface finish, 

these spring-loaded indexing plungers allow operators to retract the locating pin manually and return it toward its extended position when released.

Unlike lock-out indexing plungers, this spring-return design does not retain the pin in its retracted position.

Our indexing plungers support OEM machinery manufacturers, mechanical engineers, 

production managers and industrial procurement teams requiring reliable positioning components, drawing-based customization and industrial batch supply.

Product Specifications – Featured Non-Lock-Out Model

The exact knob material, locating pin material, spring material, thread pitch, pin diameter, stroke, spring force and dimensional tolerances should be confirmed against the selected product drawing.

How Does a Non-Lock-Out Steel Indexing Plunger Work?

A non-lock-out indexing plunger uses an internal spring to return the locating pin toward its extended position when the operator releases the pull knob.

The operating sequence is straightforward:

1. Engaged Position: The spring pushes the locating pin toward the mating locating hole or positioning feature.

2. Manual Retraction: The operator pulls the knob to retract the locating pin.

3. Component Adjustment: The fixture, bracket or machine component can be repositioned while the pin is withdrawn.

4. Automatic Spring Return: Releasing the knob allows the spring to extend the pin.

5. Re-Engagement: The pin enters the mating locating hole when the components are properly aligned.

This mechanism is suitable for applications requiring repeated manual positioning and automatic pin return.

A non-lock-out indexing plunger should not be confused with a lock-out or rest-position design that can retain the pin in its retracted position.

Key Product Features

Blackened Carbon Steel Body

The carbon steel threaded body provides a practical mounting structure for industrial machinery and positioning assemblies.

The blackened surface finish gives the steel body a dark appearance and may provide limited surface protection depending on the treatment process and any supplementary coating.

Blackening should not be assumed to provide the same corrosion resistance as stainless steel, zinc plating or other protective coating systems.

Where corrosion performance is critical, the exact blackening process, supplementary protection and required test conditions should be specified.

Automatic Spring-Return Operation

The locating pin returns toward its extended position when the operator releases the knob.

This feature is suitable for repeated positioning operations where the pin should not remain intentionally retracted.

Manual Pull-Knob Actuation

The operating knob allows manual retraction of the locating pin during equipment adjustment and fixture repositioning.

Externally Threaded Mounting Body

The threaded body allows installation into a compatible threaded mounting hole or suitable mounting component.

M6, M8 and M10 Configurations

Multiple mounting thread sizes provide flexibility for machinery designers working with different installation spaces and mechanical assemblies.

OEM Customization

Juxin Fasteners supports drawing-based evaluation of custom thread dimensions, locating pin geometry, material specifications and dimensional requirements.

Blackened Steel vs. Nickel-Plated Steel Indexing Plungers

Both blackened and nickel-plated steel indexing plungers can be used in industrial positioning systems, but their surface finishes differ.

The correct surface finish should be selected according to the equipment environment, customer specifications and engineering requirements.

Non-Lock-Out vs. Lock-Out Indexing Plungers

The featured blackened steel indexing plunger on this page is the non-lock-out spring-return type.

Available Indexing Plunger Types and Sizes

In addition to the featured blackened steel spring-return model, 

Juxin Fasteners offers a broad range of indexing plungers with different materials, structural configurations, operating mechanisms and thread sizes.

The following portfolio includes 40 listed configurations across seven product groups.

1. Ultra-Miniature Stainless Steel Indexing Plungers

Compact stainless steel indexing plungers for miniature positioning systems and space-constrained mechanical assemblies.

Lock-Out Type

• M5 × 0.8

• M5 × 0.5 – Fine Thread

Non-Lock-Out / Spring-Return Type

• M5 × 0.8

• M5 × 0.5 – Fine Thread

2. All-Stainless-Steel Indexing Plungers – Standard Metric Threads

All-stainless-steel configurations for industrial machinery and positioning systems requiring stainless steel construction.

Non-Lock-Out / Spring-Return Type

• M6

• M8

• M10

Lock-Out / Rest-Position Type

• M6

• M8

• M10

3. All-Stainless-Steel Indexing Plungers – Fine Metric Threads

Fine-thread stainless steel indexing plungers for specialized mounting and mechanical positioning requirements.

Non-Lock-Out / Spring-Return Type

• M6 × 0.75

• M8 × 1.0

• M10 × 1.0

Lock-Out / Rest-Position Type

• M6 × 0.75

• M8 × 1.0

• M10 × 1.0

4. Carbon Steel Indexing Plungers

Carbon steel indexing plungers for industrial machinery, adjustable mechanical assemblies and manufacturing fixtures.

Non-Lock-Out / Spring-Return Type

• M6

• M8

• M10

Lock-Out / Rest-Position Type

• M6

• M8

• M10

The featured blackened steel indexing plunger belongs to the carbon steel spring-return category.

5. Stainless Steel Indexing Plungers with Plastic Base – Standard Metric Threads

Combined stainless steel and plastic-base configurations for specific industrial equipment and positioning requirements.

Non-Lock-Out / Spring-Return Type

• M6

• M8

• M10

Lock-Out / Rest-Position Type

• M6

• M8

• M10

6. Nickel-Plated Carbon Steel Indexing Plungers

Nickel-plated steel indexing plungers for industrial positioning mechanisms and general machinery applications.

Non-Lock-Out / Spring-Return Type

• M6

• M8

• M10

Lock-Out / Rest-Position Type

• M6

• M8

• M10

7. Stainless Steel Indexing Plungers with Plastic Base – Fine Metric Threads

Fine-thread stainless steel and plastic-base configurations for specialized mounting and adjustment requirements.

Non-Lock-Out / Spring-Return Type

• M6 × 0.75

• M8 × 1.0

• M10 × 1.0

Lock-Out / Rest-Position Type

• M6 × 0.75

• M8 × 1.0

• M10 × 1.0

Metric Thread Selection Guide

The following standard coarse-thread pitches are provided as engineering references.

Fine-Thread Options Across the Product Range

• M5 × 0.5

• M6 × 0.75

• M8 × 1.0

• M10 × 1.0

Thread availability depends on the selected product family and configuration.

Standard coarse-thread pitches are reference values and must not be assumed for every individual model without checking its drawing.

Metric-to-Inch Diameter Reference

These conversions represent nominal metric thread diameters only.

Metric threads and UNC/UNF threads are not interchangeable. Any custom inch-thread design requires separate engineering evaluation.

Engineering Selection Guide for Steel Indexing Plungers

1. Mounting Thread Diameter and Pitch

Verify the external thread diameter, pitch, installation depth and mating threaded component.

Correct thread engagement is essential for secure installation.

2. Locating Pin Diameter

The locating pin diameter must be compatible with the mating locating hole or positioning feature.

Pin-to-hole clearance and dimensional tolerances influence positioning repeatability.

3. Retraction Stroke

The pin must retract far enough to disengage the mating component during repositioning.

Engineers should verify the required stroke against the mechanical assembly.

4. Spring Force

Spring force influences manual operating effort and the force available for pin extension.

Initial and final spring-load values should be confirmed against the selected model specification.

5. Surface Finish and Corrosion Resistance

Blackened carbon steel may be suitable for many general industrial applications.

However, corrosion resistance depends on the specific surface treatment, supplementary protection and operating environment.

For outdoor, high-humidity, chemically exposed or frequently washed equipment, material and coating suitability should be evaluated carefully.

6. Installation and Retention

Review mounting thread engagement, tightening requirements, installation accessibility and vibration conditions.

7. Operating Mechanism

Select a non-lock-out indexing plunger when automatic spring return is required.

Select a lock-out indexing plunger when the pin must remain retracted during equipment adjustment without continuous manual operation.

8. Mechanical Loads and Safety

Indexing plungers are primarily mechanical positioning components.

Their suitability for shear loads, vibration, impact or safety-related functions must be established through application-specific engineering evaluation.

Industrial Applications

Industrial Automation Equipment

Steel indexing plungers are used in adjustable mechanical assemblies, manual positioning systems and equipment setup mechanisms.

Spring-return operation allows the locating pin to re-engage automatically when released and properly aligned.

Jigs and Manufacturing Fixtures

Indexing plungers support repeatable mechanical positioning in assembly jigs, inspection fixtures, workholding accessories and production tooling.

They allow operators to disengage and reposition fixture components during manufacturing operations.

CNC Machinery and Machine Tools

Spring-loaded indexing plungers can be integrated into adjustable machine accessories, auxiliary positioning systems and fixture assemblies.

The selected design should be evaluated for installation dimensions, vibration and mechanical operating conditions.

Automotive and EV Manufacturing Equipment

Automotive production fixtures, assembly tooling and adjustable manufacturing equipment can use indexing plungers for mechanical positioning.

Spring-return designs are useful where frequent manual engagement and release are required.

Packaging Machinery

Adjustable guides, brackets and changeover mechanisms may incorporate indexing plungers for repeatable positioning.

Electrical Equipment Manufacturing

Indexing plungers can support mechanical positioning in industrial electrical equipment assembly fixtures, production workstations and adjustable manufacturing tooling.

Electronics and Semiconductor Equipment Manufacturing

Selected indexing plungers may be used in mechanical fixtures, adjustable assemblies and non-process-critical equipment positioning applications.

Material cleanliness, dimensional accuracy and operating conditions should be evaluated for specialized equipment.

Benefits for OEM Engineers, Production Managers and Procurement Teams

For Mechanical and Design Engineers

• Spring-loaded mechanical positioning

• Standard metric mounting thread options

• Carbon steel construction

• Blackened surface finish

• Drawing-based customization

• Multiple material and operating configurations across the wider product range

For Production Managers

• Convenient manual adjustment

• Automatic spring return

• Repeatable fixture positioning

• Support for equipment setup

• Reduced need for separate manual re-engagement

For Industrial Procurement and Supply Chain Teams

• Multiple indexing plunger configurations

• Standard and custom component sourcing

• Material and surface-finish selection

• OEM engineering support

• Industrial batch supply

• Technical documentation review

OEM Manufacturing and Custom Indexing Plunger Solutions

With more than 20 years of industrial fastener manufacturing experience, 

Juxin Fasteners supports international OEM customers and industrial equipment manufacturers with standard and custom-engineered mechanical components.

Our team can evaluate customer requirements for:

• Carbon steel and stainless steel materials

• Blackened and nickel-plated surface finishes

• Standard metric mounting threads

• Fine-thread configurations

• Custom locating pin diameters

• Modified pin lengths and retraction strokes

• Spring-force requirements

• Knob configurations

• Lock-out and non-lock-out mechanisms

• Drawing-specific dimensional tolerances

• OEM part-number identification

• Industrial production quantities

Custom manufacturing feasibility, inspection requirements and delivery schedules are reviewed according to each project.

Quality Control and Technical Documentation

Juxin Fasteners supports engineering and procurement teams requiring product specifications, dimensional inspection requirements and material documentation.

Our company maintains RoHS and REACH compliance documentation.

Product-specific documentation can be reviewed according to the applicable materials, surface finishes and customer requirements.

Customers are encouraged to provide 2D drawings, 3D CAD models or detailed technical specifications for evaluation.

Frequently Asked Questions

What is a non-lock-out indexing plunger?

A non-lock-out indexing plunger is a spring-loaded mechanical positioning component that returns its locating pin toward the extended position when the operator releases the knob.

Does this steel indexing plunger have a locking function?

No. The featured model is a non-lock-out spring-return type and cannot intentionally retain its locating pin in the retracted position.

What is the surface finish of this indexing plunger?

The carbon steel body has a blackened surface finish. 

The exact blackening process and corrosion-performance requirements should be confirmed when specified by the customer.

What sizes are available?

The featured steel indexing plunger range includes M6, M8 and M10 nominal mounting thread sizes.

What is the difference between blackened steel and nickel-plated steel indexing plungers?

Both use carbon steel body configurations, but their surface treatments differ. Nickel plating and blackening provide different surface characteristics and should be selected according to the intended application.

Are stainless steel indexing plungers available?

Yes. Juxin Fasteners also offers stainless steel, all-stainless-steel, ultra-miniature and stainless steel with plastic-base indexing plunger configurations.

Do you supply lock-out indexing plungers?

Yes. Lock-out versions are available in selected steel and stainless steel product families.

Can indexing plungers be customized for OEM equipment?

Yes. We support engineering evaluation of custom mounting threads, locating pin dimensions, spring-force requirements, materials, surface finishes and other drawing-based specifications.

Can I request 2D drawings, 3D models or samples?

Please provide the required product configuration and technical specifications. Our team can review drawing availability, CAD requirements, sample options and quotation details.

Request a Quotation – Blackened Steel Indexing Plungers

Looking for a manufacturer of blackened steel indexing plungers for industrial machinery, automation systems, manufacturing fixtures or OEM equipment?

Juxin Fasteners supplies spring-loaded indexing plungers in carbon steel, nickel-plated steel, stainless steel and other configurations.

We support OEM customers requiring standard products, custom engineering solutions and industrial batch supply.

Please Include the Following Information in Your RFQ:

• Required indexing plunger type

• Non-lock-out or lock-out operation

• Mounting thread diameter and pitch

• Locating pin diameter and retraction stroke

• Body and pin material requirements

• Surface finish specifications

• Spring-force requirements

• 2D drawings or 3D CAD models, if available

• Estimated annual usage and order quantity

• Required delivery destination

Juxin Fasteners – Precision Fastener Manufacturer

Email: info@juxinfasteners.com

Website: https://www.juxinfasteners.com/

Steel Indexing Plungers | Blackened Carbon Steel | Non-Lock-Out Spring Return | OEM Custom Manufacturing

Packaging Standard

At Juxin Fasteners, we apply standardized export packaging to ensure product protection, traceability, and compliance with international logistics requirements.

1. Standard Export Packaging

Unless otherwise specified, all products will be packed according to our factory standard export packaging, which includes:

Moisture-resistant inner protection

Poly bag or small box packing as required

Reinforced export cartons

Clear labeling with part number, specification, batch number, and quantity

Palletizing for sea or air shipment when necessary

Our standard packaging is designed to ensure safe transportation, efficient warehousing, and long-distance international shipping.

2. Customized Packaging Options

We also provide customized packaging solutions according to customer requirements, including but not limited to:

Private labeling

Customized barcodes

Specific carton dimensions

Retail packaging

Special pallet configuration

Customer-specific marking and identification

So that you know, customized packaging may involve additional costs and extended lead time depending on the complexity of the requirements.

3. Compliance & Quality Assurance

All packaging processes are controlled under our ISO 9001 quality management system to ensure consistency, traceability, and product integrity throughout the supply chain.