Clear transparent plastics

 

• Clear transparent plastics.
• Clear plastic part.
• Transparent plastic products.
• SAN,PMMA,PS,PC raw material.
• Medical, Consumer, Automotive, Electronic Industrial.
• Product description: Rich experience producing transparent plastics part mold and part in china. It needs high-quality requests for the injection molding control process.

Specifications of transparent injection molding material

Clear transparent plastics characteristics: transparent insulation thermoplastic environmental protection plastic products, plastic transparent. After burning the odorless tasteless. It does not produce poisonous gas. Transparent, surface water ripple, crystal point, ones like white, grease, and toughness. And strong resistance, chemical resistance, good resistance to impact strength. Low-temperature resistance to impact strength is also good. Is about 20% higher than the PVC standard). Used for blister, folding boxes, packaging, printing, CARDS, etc.

Transparent insulation use of transparent insulation is used in electronics, printing, packaging, insulation, soft lines. A display screen saver PET, membrane switch, membrane Windows, printing film, puzzle film base, stickers bottom paper, glue. Silicon coating, belt, instrument panel, cable capacitance motor gasket. Insulation stripping, furniture, window film, protective film inkjet printing. And decoration, etc. PC transparent insulation slices are double-sided polishing film, have good pervious to light quality, and high dimensional stability. It can make the required electroplating process and screen printing various textures, decorations, and optical effects for aesthetics.

PC material

 

PC is a kind of amorphous, odorless, non-toxic. Highly transparent colorless or yellowish thermoplastic engineering plastics. Has excellent physical and mechanical properties.

Especially the excellent impact resistance. High tensile strength, bending strength, compression strength. Creep is small, size stable. Has good heat resistance. And low-temperature resistance. A relatively wide temperature range has stable mechanical properties.

Dimensional stability, electrical properties, and flame retardancy can use for a long time under 60 ~ 120 ℃. No obvious melting point, in 220-230 ℃ in the molten state.

Due to the molecular chain rigidity, resin melt viscosity. Bibulous rate is small, small shrinkage rate, high dimensional accuracy.

Good dimensional stability, membrane permeability is small. Self-extinguishing material. Light is stable. But not resistant to ultraviolet light, good weather ability.

They can withstand oil, acid, alkali resistant, oxidizing acid, and amine, ketone, soluble in chlorinated hydrocarbons. And aromatic solvents, Easy cause hydrolysis and crack in the water for a long time.

The disadvantage is that because of the fatigue strength is poor, prone to stress cracking. The solvent resistance is poor, with poor wear resistance. The product features environmental protection. Flame retardant, impact resistance, high and low-temperature resistance. Good dimensional stability, and good insulation.

Specifications china transparent injection molds making

1. Our clear transparent parts are widely recognized and trusted by users. And can meet continuously developing economic and social needs.

2. A quality hot runner already widely used to reduce cycle times and maintaining the shinning. And clear surfaces during long-time production.

3. We guarantee the mold life and injection mold spare part use /changeable.

4.S7/H13/2344  after heat-treat. The hardness will be up to  52-54 HRC to get longer mold life.NAK80. 718 is also a good choice for transparent clear injection mold making in China.

5. High-quality steel has to be tested and certificated from steel suppliers in accordance with the transparent parts.

injection mold slider design

 

Injection Mold Slider Design: Key Principles & Best Practices

Sliders (also called side-action cores or cam mechanisms) are essential mold components used to form undercuts or complex geometries that cannot be released by standard ejection systems. Here’s a comprehensive guide to slider design for injection molds:

1. When to Use Sliders?

Sliders are needed when:

• The part has external undercuts (e.g., side holes, hooks, threads).
• The part has internal undercuts (e.g., snap fits, internal grooves).
• Straight ejection would damage the part.

2. Slider Types & Mechanisms

Type	Description	Application
Angled Pin Slider	Driven by a tapered pin during mold opening.	Simple side undercuts, low-cost.
Hydraulic Slider	Uses a hydraulic cylinder for controlled movement.	Complex undercuts, high precision.
Rack & Pinion	Gear-driven for smooth linear motion.	Long travel distances.
Lifter-Assisted	Combines a lifter + slider for deep undercuts.	Internal undercuts.

3. Critical Design Parameters

(1) Slider Movement Calculation

• Travel Distance = Undercut Depth + (1~2mm safety margin).
• Angle Pin Angle (typically 15°–25°):
• Larger angle = Faster movement but higher friction.
• Smaller angle = Smoother but slower action.

(2) Guiding & Locking

• Wear Plates (hardened steel) reduce friction.
• Locking Blocks prevent slider deflection during injection.

(3) Cooling Considerations

• Avoid cooling lines near sliding surfaces to prevent warping.
• Use baffles/bubblers if cooling is necessary.

(4) Draft Angles

• Add 1°–3° draft on slider contact surfaces to ease release.

4. Step-by-Step Slider Design Process

1. Identify Undercut Location

• Check part CAD for undercuts requiring side action.

1. Choose Slider Type

• Angled pin for simple designs; hydraulic for complex motions.

1. Calculate Travel & Angle

• Ensure full undercut clearance without interference.

1. Design Slider & Core

• Use split cores if undercut is deep.

1. Add Locking & Ejection

• Locking blocks + return pins for stability.

1. Simulate Motion

• Check for collisions in mold-opening sequence.

5. Common Slider Defects & Solutions

Issue	Cause	Solution
Slider Sticking	Poor lubrication/wear.	Use self-lubricating materials (e.g., bronze guides).
Part Damage	Insufficient travel/draft.	Increase slider stroke or draft angle.
Flash Formation	Worn locking surfaces.	Replace hardened lock blocks.

6. Advanced Tips

• Micro-Sliders: For tiny undercuts (<2mm), use spring-loaded mini-sliders.
• Collapsible Cores: For threaded parts, use retractable cores.
• 3D-Printed Sliders: For prototypes, use metal 3D printing for complex geometries.

Conclusion

A well-designed slider ensures smooth demolding of complex parts while maintaining mold longevity. Prioritize:
✔ Precise travel calculation
✔ Robust locking/guiding
✔ Proper cooling & lubrication

For high-volume production, hydraulic sliders offer better control, while angled pin sliders are cost-effective for simpler molds.

 

injection mold slider

In conclusion, the design of an injection mold slider is a critical factor in the success of any injection molding process. By carefully considering factors such as material choice, shape, mechanism, placement, and maintenance, it is possible to design a slider that functions correctly and produces high-quality parts. With careful planning and attention to detail, it is possible to create injection molds that deliver excellent results time and time again.

As a professional china injection mold company, we focus on precision mold making manufacturing
in china for the complicated slider.

Precision injection molding characteristics

      The Precision injection molding is generally referred to as the precision of forming parts and surface quality is demanding high technology, some people think that precision injection is the size of plastic parts to achieve the accuracy of 0.01 ~ 0.001 mm injection molding process. In recent years, with the electronic, medical, communications, automotive, and other industries. With the rapid development of people’s plastic products, high precision, high-performance requirements. The traditional plastic molding process has been difficult to meet the current high standards. Is one of the most important plastics molding methods. Therefore, precision injection molding technology more and more people’s attention. Making precision injection molding technology continues to progress, new technology continues to emerge. Factors that affect precision injection molding require high dimensional accuracy, low warpage, excellent transfer characteristics, and excellent optical properties.

Therefore, it is on the injection molding machine, injection mold, molding process, raw material properties. And formulations have special requirements, affecting the many factors of precision injection molding. According to the current actual production point of view, the impact of precision injection molding factors are the following aspects:

1. Plastic shrinkage design of precision plastic products, plastic shrinkage should be considered.
2. The shape and size of the product The shape and size of the plastic parts have a great impact on the accuracy of the parts, the production practice shows that the more complex the shape of the product and the larger the size, the lower the accuracy
3. Mold structure The accuracy of plastic parts and mold cavity number and production volume are closely related. It is also shown that the accuracy of the single-cavity mold structure is higher than that of the multi-cavity mold, and the accuracy of small-mass production is higher than that of large quantities.

lastic Injection Mold Design: Principles, Components & Gating Systems

 

Understanding Plastic Injection Mold Design: A Comprehensive Guide

For manufacturers and engineers, the plastic injection mold is the most critical tool in the production cycle. While every mold is customized for a specific product, the underlying engineering principles remain constant. A well-designed mold ensures part consistency, reduces cycle times, and extends the lifespan of the tool.

The basic structure of an injection mold consists of three functional groups: the Gating System, Molded Parts, and Structural Components.

1. The Gating System: The Pathway for Success

The gating system is the "plumbing" of the mold. It guides the molten plastic from the injection machine nozzle into the mold cavity.

• The Sprue: The primary entry point. To prevent leakage and "freezing" at the nozzle, the sprue inlet is typically 0.5mm to 1.0mm larger than the machine nozzle. A standard 3° to 5° taper is added for easy ejection.

• Cold Slug Well: A critical "trap" at the end of the sprue that catches the cooler material from the nozzle tip. This prevents cold spots from clogging the gates or creating blemishes on the final part.

• Runners (Shunts): These channels distribute plastic to multiple cavities. Professional molders prefer trapezoidal or circular runners for balanced flow and minimal pressure drop.

• The Gate: The narrowest point in the system. It controls the velocity of the melt and acts as a "seal" once the part is full, preventing backflow.

2. Cavity and Core: The Heart of the Shape

The Molded Parts are what define the final geometry and surface texture of your product.

• Cavity (Female): Forms the exterior surface.

• Core (Male): Forms the interior features (like holes or ribs).

• Precision Finish: To ensure easy "stripping" or ejection, the surface roughness is usually kept at Ra < 0.32µm. For high-gloss or transparent parts, vacuum heat treatment and mirror polishing are applied to the tool steel.

3. Venting and Cooling: Ensuring Part Quality

Even the best gating system will fail without proper venting and thermal management.

• Venting (Air Escapes): As plastic fills the mold, air must escape. Without proper vent slots (usually 0.03mm to 0.05mm deep), the air compresses, causing "burn marks" or "short shots."

• Cooling Systems: Efficiency is key. Most Chinese injection mold companies utilize internal water channels to regulate temperature. Uniform cooling is the secret to preventing part warpage and achieving fast cycle times.

4. Structural Components: The Backbone

The structural parts, such as guide pillars, ejector pins, and stripper plates, do not form the plastic but are essential for the mold's mechanical operation. They ensure the mold opens and closes with micron-level alignment every single time.

Why Choose a Professional China Injection Mold Company?

Partnering with an experienced manufacturer ensures that these technical principles are applied correctly. From choosing the right tool steel (like P20 or S136) to optimizing the gate location, professional mold design minimizes long-term production costs and ensures high-yield manufacturing.

 

 

plastic injection molding sink mark

 

The reasons for sink mark in plastic products are as follows:

Reasons for injection molding sink mark

Sink marks in injection molding are common defects that occur when the surface of a molded part shrinks and creates a depression or dimple. This typically happens because the inner part of the material cools and shrinks faster than the outer surface, pulling the surface inward. Sink marks are most noticeable on thicker sections of the part or near ribs, bosses, or other features that create variations in wall thickness.

Causes of Sink Marks:

1. Insufficient Cooling Time:

• If the cooling time is too short, the outer surface solidifies while the inner material is still cooling and shrinking, causing sink marks.

1. Inadequate Holding Pressure or Time:

• Holding pressure helps pack additional material into the mold to compensate for shrinkage. If the pressure or time is insufficient, the material shrinks excessively, leading to sink marks.

1. Excessive Wall Thickness:

• Thicker sections cool more slowly, increasing the likelihood of shrinkage and sink marks.

1. High Material Shrinkage Rate:

• Some materials, such as semi-crystalline plastics (e.g., polypropylene or nylon), have higher shrinkage rates, making them more prone to sink marks.

1. Improper Gate Location or Size:

• If the gate is too small or poorly located, it can restrict the flow of material, preventing adequate packing and leading to sink marks.

1. High Melt Temperature:

• Excessive melt temperature can increase material shrinkage as it cools, contributing to sink marks.

---

How to Prevent Sink Marks:

1. Optimize Wall Thickness:

• Design parts with uniform wall thickness to ensure even cooling. If thick sections are unavoidable, use coring or ribbing to reduce material volume.

1. Increase Holding Pressure and Time:

• Apply sufficient holding pressure and extend the holding time to pack more material into the mold and compensate for shrinkage.

1. Adjust Cooling Time:

• Ensure adequate cooling time to allow the entire part to solidify uniformly.

1. Use Low-Shrinkage Materials:

• Select materials with lower shrinkage rates, such as amorphous plastics (e.g., ABS, PC) or filled resins.

1. Optimize Gate Design:

• Use larger gates or position them near thicker sections to ensure proper material flow and packing.

1. Control Melt Temperature:

• Avoid excessively high melt temperatures to minimize shrinkage.

1. Add Mold Features:

• Incorporate mold features like gas vents or cooling channels to improve cooling efficiency and reduce shrinkage.

---

Corrective Actions for Existing Sink Marks:

• Increase holding pressure and time.
• Reduce melt temperature.
• Extend cooling time.
• Modify part design to reduce wall thickness or add coring.
• Adjust gate size or location.

By addressing these factors, you can minimize or eliminate sink marks and improve the quality of injection-molded parts.

High-Precision Injection Mold Design Services in Shanghai - Medical & Industrial Tooling

 

High-Precision Injection Mold Design Services in Shanghai - Medical & Industrial Tooling

 

Mold design[/caption]

Professional Injection Mold Design Services: From Concept to Production

Based in Shanghai, China, we specialize in custom injection mold design, rapid prototyping, and high-volume manufacturing. Our team bridges the gap between a creative concept and a manufacturable product, ensuring high quality at a competitive price.

Why Choose a China-Based Engineering Partner for Your Mold Design?

Many clients approach us with only a physical sample or a rough sketch. Our job is to turn those "Design Keys" into reality:

• Reverse Engineering: We refine and optimize existing samples to improve structure and reduce costs.

• DFM (Design for Manufacturing): We analyze your 3D models to ensure they are optimized for the molding process, reducing future tooling risks.

   

• Cost-Effective Innovation: We help you achieve premium aesthetics and functionality without unnecessary investment.

Advanced Engineering & Software Expertise

Our design team is proficient in industry-leading 3D software to ensure 100% accuracy:

• SolidWorks & UG (NX): For complex structural design.

• Pro/Engineer (Creo) & Catia: For high-end industrial surfacing.

• Moldflow Analysis: We simulate the injection process to predict flow, cooling, and potential defects before the steel is cut.

1. Avoiding Sink Marks

Sink marks are surface depressions caused by localized shrinkage.

• The Fix: Maintain consistent wall thickness.

• Pro Tip: Gate size and location are crucial. A gate that freezes too early prevents proper packing. We optimize gate placement to ensure the cavity is fully packed.

2. Preventing Warpage

Warping is caused by uneven internal stress during cooling.

• The Fix: Minimize transitions between thick and thin sections.

• Pro Tip: Use ribs instead of increasing wall thickness. Rib thickness should not exceed 60% of the main wall thickness to prevent sink marks on the opposite side.

3. Optimizing Draft Angles

To prevent parts from sticking and to eliminate ejector marks:

• Standard: A draft angle of 1° to 2° is usually required.

• Texture: If the surface is textured, a larger draft angle is necessary to protect the finish.

Specialized Capabilities: Medical & Automotive Mold Excellence

Our engineering team brings decades of combined experience to two of the most demanding sectors in the industry: Medical Devices and Automotive Components. We understand that these sectors require more than just a mold.

 

Injection Mold Process

 

Injection Mold Process

[caption id="attachment_4686" align="alignnone" width="300"] Injection Mold Process[/caption]

Core Tooling Technologies: Precision Machining Excellence

At the heart of a high-quality injection mold lies precision machining. We invest in high-end equipment and master-level craftsmanship to ensure every cavity, core, and insert meets your exact specifications. Our toolroom integrates three critical machining technologies:

1. High-Speed CNC Machining (The Backbone of Accuracy)

Our CNC department focuses on rapid material removal while maintaining tight dimensional tolerances. By using high-speed spindles and advanced CAM programming, we minimize manual benchwork and ensure consistency.

• Capabilities: We handle everything from large mold bases to intricate electrode milling.

• Precision: Achievable tolerances up to ±0.005mm.

• Surface Finish: Optimized tool paths result in superior surface finishes, reducing the need for extensive polishing and preventing part drag marks.

• Hard Milling: Capability to machine hardened tool steel (up to 58-60 HRC), ensuring long-term mold stability and alignment.

2. Precision EDM – Electrical Discharge Machining (The Art of Complexity)

For geometries that traditional cutting tools cannot reach—such as sharp internal corners, deep ribs, and complex textures—our EDM process is indispensable.

• Intricate Details: Perfect for creating "blind" pockets and thin-walled features with high aspect ratios.

• Mirror Finishing: Our "Mirror EDM" capability produces high-gloss surfaces directly on the steel, essential for clear plastic parts or medical-grade finishes.

• Electrode Management: We use high-grade graphite or copper electrodes, precision-milled on our CNCs, to ensure the spark erosion perfectly matches the 3D design.

• Uniform Texture: Ensures consistent VDI surface finishes across the entire mold cavity.

3. Precision Wire-Cutting (The Standard for Inserts & Cores)

Wire-cut EDM is our go-to technology for through-hole features, complex parting lines, and high-precision mold inserts.

• Extreme Tolerance: Ideal for fitting interlocking mold components where a "zero-clearance" fit is required.

• Vertical Accuracy: Ensures perfectly straight walls and tapered angles for lifters and sliders.

• Material Integrity: The non-contact nature of wire-cutting prevents mechanical stress on the steel, preserving the material properties of expensive tool steels like S136 or H13.

• Repeatability: Highly automated process ensures that replacement inserts are identical to the originals, simplifying your long-term mold maintenance.

Technical Specifications Table

Feature	CNC Machining	EDM (Sink)	Wire-Cut EDM
Primary Use	Roughing & Finishing	Deep ribs, Sharp corners	Inserts, Sliders, Ejector holes
Min. Corner Radius	0.1 mm	0.02 mm	0.05 mm
Max. Hardness	Up to 60 HRC	No limit (any conductive)	No limit (any conductive)
Surface Finish	Ra 0.8 - 1.6 μm	Ra 0.2 μm (Mirror)	Ra 0.4 - 0.8 μm
Best For	Speed & Bulk removal	Complexity & Texture	Precision & Straightness

Our Quality Commitment

Every machined component undergoes rigorous inspection before assembly. We utilize CMM (Coordinate Measuring Machines) and Optical Projectors to verify that the CNC, EDM, and Wire-cut outputs align 100% with the digital twin of your mold.

"Precision in the toolroom means reliability in your production line."

[caption id="attachment_4886" align="alignnone" width="300"] Injection Mold Process[/caption]

Our Core Technical Capabilities

1. Advanced Tooling & Mold Design

Our engineering department utilizes state-of-the-art CAD/CAM/CAE software to ensure every mold is optimized for the production cycle.

• DFM (Design for Manufacturing): We provide comprehensive DFM reports before steel cutting to identify potential issues such as sink marks, air traps, or gate vestiges.

• Multi-Cavity Expertise: We design high-efficiency multi-cavity molds (2 to 128 cavities) to significantly reduce unit costs for high-volume orders.

• Hot & Cold Runner Systems: Expert integration of systems like Yudo, Mold-Masters, and Husky to optimize material usage.

2. Precision Manufacturing Processes

We utilize a hierarchy of machining technologies to guarantee tolerances as tight as ±0.01mm:

• High-Speed CNC Machining: For rapid and precise removal of material and complex geometries.

• Precision EDM (Electrical Discharge Machining): For sharp corners, deep ribs, and intricate textures that mechanical cutting cannot reach.

• Wire-Cut EDM: Essential for producing high-precision inserts and complex mold cores.

3. High-Performance Injection Molding

Our facility in Shanghai is equipped with advanced injection machines (ranging from 50T to 1200T) capable of handling a wide array of resins:

• Engineering Plastics: ABS, PC, Nylon (PA6/PA66), POM, PBT.

• High-Performance Polymers: PEEK, PPS, PSU, LCP.

• Elastomers: TPE, TPU, Silicon.

 

Our Process: From Concept to T1 Sample

1. Inquiry & Quotation: 24-48 hour response time with preliminary cost analysis.

2. DFM & Mold Design: Detailed structural analysis and 3D design approval.

3. Tooling Fabrication: Weekly progress reports with photos and videos.

4. Mold Trial (T1): Sample submission for customer validation.

5. Quality Inspection: Full dimensional report using CMM and projector.

6. Mass Production or Mold Shipping: Safe seaworthy/airworthy packaging.