injection molding lifter and slider

What is the Difference Between Injection Molding Lifter and Slider?

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What is an injection molding lifter and slider? They are important components of injection mold to make the complex mold design come true. In the previous posts, we have introduced the injection molding lifter and injection molding slider already. Today, we will compare those two important mold components, and learn what are the difference, relationships and how to choose the right mold design in the injection molding process.

Understanding of Injection Molding Lifter and Slider

What is Injection Molding Lifter?

An injection molding lifter, also known as an ejector pin or stripper pin, is a crucial component used to push or eject finished plastic parts from the mold cavity after molding. It allows for the creation of complex and intricate designs with ease and efficiency.

What is an injection molding lifter? Read our previous blog to learn more about injection molding lifters.

What is Injection Molding Slider?

Injection molding sliders are mechanical components incorporated into the mold design to produce complex molded parts. Not like lifters, sliders enable the creation of complex shapes within the molded part itself. These shapes may include holes, threads, or various internal features that cannot be achieved using traditional straight-pull molds.

Interested in learning more about injection molding sliders? Read our previous blog Injection Molding Slider Design: Enhancing Molding Capabilities with Side Action

Differences Between Injection Molding Lifter and Slider?

In the previous posts, we have learned the injection molding lifter and slider in detail. As the important parts of injection molds, what are the differences between injection molding lifter and slider? I think we can analyze them from three impacts, design, function, and application,

  • Design: The injection molding lifter is designed for the smooth ejection of complex parts from the mold. They push the part out of the mold after it solidifies. On the other hand, sliders are used to create unique features within the molded part itself, such as undercuts, threads, holes, or other complex shapes.
  • Functionality: The injection molding lifter is used for part ejection, and the injection molding slider is used to enhance the appearance and functionality of the final product.
  • Applications: The injection molding lifter is usually used when the injection molded parts have concave edge features, and the injection molding slider is used for internal features or cuts that the straight pull molds cannot achieve.

Relationship Between Injection Molding Lifter and Slider?

Injection molding lifter and slider can work together to create intricate and complex part designs beyond traditional straight-pull molds’ capabilities. Manufacturers can produce parts with multi-level undercuts, threads, holes, or unique geometries by combining lifters for external undercuts and sliders for internal features. The coordination between lifters and sliders allows for the formation of complex mechanisms and moving parts within the molded components, enabling the production of sophisticated products for various industries.

Examples of Complementary Use in Injection Molding:

  • Automotive Parts: In automotive applications, lifters and sliders work in synergy to produce components like door handles with both external undercuts for ease of handling and internal sliders to create intricate texture or embossing for aesthetics.
  • Electrical Connectors: Electrical connectors often require complex shapes and internal undercuts to accommodate multiple pins. By utilizing lifters and sliders, manufacturers can produce connectors with intricate designs and precise functionalities.
  • Medical Devices: Medical devices often demand intricate designs and part features to meet specific requirements. Lifters and sliders enable the creation of intricate internal structures and undercuts, allowing for the fabrication of precise and functional medical components.

How to Choose Between Lifters and Sliders?

Choosing between an injection molding lifter and slider depends on several factors, including the part design, complexity, production requirements, and cost considerations.

Part Design

Examine the part design and identify the features that require undercuts or internal shapes. If the part has internal features that cannot be achieved with a simple straight-pull mold, sliders may be the better choice.

Mold Complexity

Consider the complexity of the mold design and construction. Lifters are relatively simpler and easier to integrate into the mold compared to sliders, which may require additional components and advanced mold design.

Production Volume

Evaluate the production volume. For low to medium volumes, lifters may be more cost-effective and practical. However, for high-volume production, sliders can offer better efficiency and reduced cycle times.

Cost Considerations

Analyze the cost implications of using lifters or sliders. Lifters are generally more economical and easier to implement, while sliders may involve higher initial costs and maintenance.

Part Release Requirements

Determine the ease of part release. If the part can be easily released with simple lifters, it might be a more straightforward choice. However, if complex internal features necessitate the use of sliders, they will be essential for proper part ejection.

Mold Life and Maintenance

Consider the lifespan and maintenance requirements of the mold. Lifters might have longer life spans and lower maintenance needs compared to sliders.

Ultimately, the choice between lifters and sliders should be based on the specific requirements of the part design, production volume, and available resources. In some cases, a combination of both lifters and sliders may be used to achieve the desired part complexity and optimize the injection molding process. Collaborating with experienced manufacturers can help ensure the best solution for your specific application.


Recognizing the importance of injection molding lifter and slider, and the relationships and differences is important for designing and producing complex molded parts. They help manufacturers optimize the injection molding process, where efficiency and product quality are critical. Zhongde is an on-demand China manufacturer with experience and reputation. We offer mold design, production, and manufacturing. Welcome your consultation. Contact Us!