Difference in sliders and lifters for plastic parts

Sliders and lifters are key components in injection molding tools used to form complex plastic parts. While both are used to release undercuts and complex geometries, they differ in function, design, and application. Here’s a detailed comparison:

---

1. Function

Sliders:

Used to create external undercuts or side features such as holes, slots, or threads.

Slides laterally (perpendicular to the mold opening direction) to clear the undercut before the mold opens.

Lifters:

Used to form internal undercuts or features inside the part.

Moves at an angle to lift or push the part away from the undercut as the mold opens.

---

2. Motion

Sliders:

Moves in a straight, lateral motion.

Driven by cam pins or hydraulic mechanisms.

Lifters:

Moves in a combined angular and linear motion.

Tilts or pivots as it pushes the part out of the mold.

---

3. Design

Sliders:

Consist of a sliding block that is guided by a cam pin or rail.

Requires space in the mold for lateral movement.

Lifters:

Feature a lifting pin or bar with an angled head.

Typically require less space compared to sliders.

---

4. Applications

Sliders:

Suitable for external features like:

Side holes.

Side slots.

Side protrusions or ribs.

Lifters:

Suitable for internal features like:

Undercut cavities.

Snap-fit hooks.

Internal ribs or threads.

---

5. Complexity

Sliders:

More complex to design and manufacture due to the need for precise lateral movement.

Increases mold size and cost.

Lifters:

Simpler compared to sliders but can be challenging to design for angled and precise movements.

Generally smaller and cost-effective.

---

6. Maintenance

Sliders:

Requires regular maintenance due to wear on sliding surfaces.

Higher risk of misalignment over time.

Lifters:

Easier to maintain as they have fewer moving parts.

Lower wear compared to sliders.

---

7. Cost

Sliders:

More expensive due to complex mechanisms and space requirements.

Lifters:

Less expensive as they are simpler in construction.

---

Summary Table

---

Both sliders and lifters are essential for creating detailed plastic parts with undercuts, and their selection depends on the specific design and geometry of the part.