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Overmolding Service
Lewei Precision provides advanced overmolding molding services for high-performance plastic and metal components. From rapid prototypes to on-demand production, our overmolding process delivers strong material bonding, consistent quality, and refined aesthetics. Backed by expert engineering and fast tooling, we help you achieve reliable results with scalable manufacturing efficiency.
- Rapid Tooling & Production: T1 samples available in as little as 2 weeks, supporting prototypes through scalable production.
- Certified Quality & Consistency: ISO 9001:2015, ISO 13485, ISO 14001, and IATF 16949 certified manufacturing with strict quality control.
- Engineering-Led Reliability: Professional DFM support, material selection guidance, and dependable global manufacturing capabilities.
Bring your product ideas to life quickly and accurately with our expert prototyping services.
Why Choose Lewei Precision for Overmolding?
Lewei Precision delivers reliable overmolding molding services designed to improve part performance, durability, and aesthetics. From early-stage prototypes to full-scale production, we combine precision tooling, engineering expertise, and certified quality systems to ensure consistent, high-quality overmolded components.
Precision-Driven Overmolding
Our overmolding molding services deliver accurate material bonding and tight dimensional control, ensuring consistent performance and a refined appearance across every production run.
Optimized tooling workflows shorten the time from design approval to part delivery, helping you move faster without compromising quality.
Our experienced engineers provide early-stage DFM feedback, material compatibility guidance, and bonding optimization before tooling begins.
What Is Overmolding?
Overmolding is a specialized manufacturing process in which a secondary material is molded over a rigid base component to create a single, unified part. This method is commonly used to improve grip, durability, protection, and visual appeal. With professional overmolding molding services, manufacturers can combine rigid plastics or metals with softer elastomers or secondary plastics to enhance product performance while reducing assembly steps and long term costs.
Overmolding Process
This overmolding method combines multiple plastic materials into a single part to improve strength, precision, and surface quality. Our overmolding molding services ensure reliable bonding and consistent results for both prototypes and production parts.
- Ideal for large-scale production
- Achieves detailed geometries
- Uses aluminum and steel molds
Rubber over plastic overmolding adds soft-touch features to rigid components, improving grip, comfort, and vibration resistance. It is commonly used for ergonomic parts that require enhanced usability and durability.
- Offers various color and texture options
- Seamlessly combines materials
- Increases strength and lifespan
Plastic over metal overmolding integrates metal inserts with plastic to increase structural strength while reducing assembly steps. This solution is ideal for parts that need both rigidity and lightweight performance.
- Lowers production costs
- Enhances durability
- Reduces assembly steps
Rubber over metal overmolding applies an elastomer layer to metal parts to improve impact resistance and handling. It is well suited for components exposed to repeated use and demanding environments.
- Cuts production costs
- Enhances durability
- Reduces assembly steps
Overmolding Surface Finishes
Lewei Precision provides numerous surface finish options to increase the quality, durability and the appearance of your 3D printed components. Our services can be used to fulfil your personal project requirements, whether it involves a smooth finish, protection, or a unique texture.
This finish comes directly from the molding process and is ideal for functional or internal parts where appearance is not critical. Our overmolding molding services ensure consistent surface quality and dimensional accuracy straight from the mold.
We offer a full range of SPI finishes, from Grade 3 diamond or high polish to 320 stone low polish. Available options include SPI A-1, A-2, A-3, B-1, B-2, B-3, C-1, C-2, C-3, D-1, D-2, and D-3, allowing precise control over surface texture and appearance.
Custom textures are available to improve grip, branding, and visual appeal. These finishes enhance user interaction and product differentiation while maintaining durability across overmolded components.
CNC Machining Solutions
Lewei Prototyping
Prototype tooling is ideal for early-stage validation and functional testing. Our overmolding molding services use cost-effective prototype molds to help verify part design, material bonding, and performance before moving into production.
Production Tooling
Production tooling is designed for long-term, high-volume manufacturing. Using durable steel molds, our overmolding solutions deliver stable performance, repeatability, and cost efficiency across extended production cycles.
Lewei Overmolding Finishes
SPI Finishes
Our SPI finishes range from Grade 3 diamond/high polish to 320 stone low polish. The available finishing options include SPI A-1, SPI A-2, SPI A-3, SPI B-1, SPI B-2, SPI B-3, SPI C-1, SPI C-2, SPI C-3, SPI D-1, SPI D-2, and SPI D-3.
Polished Finish
Offers a smooth and shiny surface, often used for parts that require easy cleaning or a high-end look.
Satin Finish
A smooth, semi-gloss finish that provides a balance between matte and mirror finishes, suitable for both functional and aesthetic needs.
Materials for Overmolding at Lewei Precision
Lewei Precision’s custom overmolding services enable the creation of high-performance plastic parts that combine aesthetics and functionality. Our advanced injection molding process integrates multiple materials into a single part, delivering superior quality and improved product performance.
Plastics
ABS is strong, durable, and offers good resistance to heat and impact. It’s preferred for automotive components and consumer goods.
ABS Beige(Natural)
ABS Black
ABS Black Antistatic
ABS Milky White
ABS+PC Black
ABS+PC White
Polycarbonate is extremely durable and has high impact resistance, along with excellent clarity, used for bullet-proof glass and protective gear.
PC Black
PC Transparent
PC White
PC Yellowish White
PC+GF30 Black
PMMA, or acrylic, is known for its crystal clarity and weather resistance, making it ideal for outdoor fixtures and display cases.
PMMA Black
PMMA Transparent
PMMA White
POM is strong, with a low friction surface and good dimensional stability, perfect for precision parts in mechanical applications.
Dark brown (coffee) POM 100AF
POM Black
POM Blue
POM White
Nylon is versatile, strong, and wears well against friction, commonly used for gears, bearings, and other wear-resistant surfaces.
PA(Nylon) Blue
PA6 (Nylon)+GF15 Black
PA6 (Nylon)+GF30 Black
PA66 (Nylon) Beige(Natural)
PA66 (Nylon) Black
Polyethylene is lightweight and has high resistance to impact, widely used in packaging and containers.
PE Black
PE White
PEEK is renowned for its high temperature resistance and strength, often used in aerospace and medical implant manufacturing.
PEEK Beige(Natural)
PEEK Black
Polypropylene is tough, has excellent chemical resistance, and is used for automotive parts, containers, and in packaging.
PP Black
PP White
PP+GF30 Black
Insert Molding vs Overmolding: Key Differences
Both insert molding and overmolding are advanced molding techniques used to combine multiple materials into a single component. However, each process serves a different purpose depending on the part’s functional and structural requirements.
| Comparison | Insert Molding | Overmolding |
|---|---|---|
| Manufacturing Method | Pre-formed inserts are placed into the mold before plastic injection | A secondary material is molded over an existing plastic part |
| Main Function | Provides internal strength and functional reinforcement | Enhances surface feel, protection, or appearance |
| Production Steps | Single molding cycle with no post-assembly | Multi-step process requiring multiple molding stages |
| Material Usage | Plastic molded around metal or rigid inserts | Soft elastomers molded over rigid plastic substrates |
| Strength & Durability | High structural strength and long-term reliability | Limited structural strength, focused on surface performance |
| Thread & Fastener Support | Ideal for embedded threads and wear-resistant features | Not designed for threaded or load-bearing reinforcement |
| Design Flexibility | Controlled by insert placement and mold design | Greater freedom for textures, grips, and sealing features |
| Production Efficiency | Faster cycle times and lower labor costs | Longer cycle times due to additional molding steps |
| Common Applications | Connectors, housings, reinforced components, sensors | Handles, grips, seals, protective coverings |
| Best Application Fit | Structural and functional components | Ergonomic and cosmetic enhancements |
Overmolding Capabilities
Lewei Precision’s wire EDM, part of our CNC services, efficiently crafts both simple and intricate shapes. Ideal for parts requiring high precision, this no-contact method produces minimal burrs and excels with metals like steel and titanium. Favored in aerospace, automotive, and electronics for their accuracy, we ensure tailored, precise solutions regardless of your needs.
Capability
Details/Specifications
Material Compatibility
Stainless Steel, Titanium, Aluminum, Tool Steel, Copper
Tolerance
± 0.0001 inches (0.0025 mm) or better (based on material and thickness)
Maximum Workpiece Size
Length: 16 inches (400 mm)
Width: 12 inches (300 mm)
Height: 8 inches (200 mm)
Cutting Speed
Up to 300 mm2/min (specific to material and thickness)
Surface Finish
As fine as Ra 0.2 µm
Maximum Cutting Thickness
Up to 12 inches (300 mm) – varies based on material
Wire Diameter Range
0.004 inches (0.1 mm) to 0.012 inches (0.3 mm)
Wire Diameter Range
0.004 inches (0.1 mm) to 0.012 inches (0.3 mm)
Wire Diameter Range
0.004 inches (0.1 mm) to 0.012 inches (0.3 mm)
Advantages
Advantages of Overmolding at Lewei Precision
Overmolding molding services offer multiple benefits that enhance both product performance and manufacturing efficiency.
- Improved Product Performance Combines materials to deliver better functionality and reliability.
- Enhanced Grip and Ergonomics Soft overmolded surfaces improve comfort and ease of use.
- Reduced Assembly Costs Eliminates secondary assembly by integrating materials into one part.
- Increased Durability and Impact Resistance Overmolded layers protect components from wear and damage.
- Superior Aesthetic Quality Clean finishes and color options improve product appearance.
- Scalable Manufacturing Efficiency Suitable for prototypes, low-volume runs, and high-volume production.
Applications
Applications of Overmolding at Lewei Precision
Overmolding molding services are widely used across industries to improve functionality, durability, and usability of finished parts. Common applications include:
- Grips and Handles Soft-touch surfaces that improve comfort, control, and user experience.
- Seals and Gaskets Durable overmolded seals that provide protection against moisture, dust, and vibration.
- Electronic Housings Protective enclosures with enhanced insulation and surface protection for electronic components.
- Tooling Components Overmolded parts that improve handling, safety, and long-term reliability of tools.
- Medical Device Parts Precision components with smooth finishes and ergonomic designs for medical applications.
- Structural Reinforced Assemblies Multi-material assemblies that combine strength, flexibility, and reduced assembly steps.
Overmolding Services for Diverse Industries
Lewei Precision provides reliable overmolding molding services tailored to the functional, durability, and performance requirements of multiple industries. Our multi-material manufacturing expertise supports both prototypes and production parts across demanding applications.
Quality Control and Inspection for Overmolding
At Lewei Precision, quality assurance is embedded throughout our overmolding molding services. Every project begins with pre-production mold inspection to verify tooling accuracy before sampling and production. During molding, we perform in-process inspections to monitor critical parameters and ensure consistent material bonding, dimensions, and surface quality across each run.
Before shipment, all parts undergo final part validation, including dimensional checks and visual inspection to confirm they meet design specifications and performance requirements. We also provide complete documentation and traceability, including inspection reports, material certificates, and compliance records, giving you confidence in quality, consistency, and regulatory alignment from prototype to production.
Overmolding Workflow: How We Work
Engineering Review and DFM
Before we begin, our experts carefully review your CAD files for material compatibility, design feasibility, and manufacturability, ensuring efficient tooling and avoiding production issues.
Tooling and Rapid Prototyping
We design and manufacture the molds using advanced materials, providing fast turnaround for prototype testing and design validation to confirm functionality and quality.
Overmolding Process
During molding, we inject a secondary material over a rigid substrate, achieving reliable bonding and precise dimensional accuracy. We handle multi-material components to meet your specific requirements.
Quality Control and Inspection
Each part undergoes comprehensive inspections using CMM (Coordinate Measuring Machines) to verify dimensions, tolerances, and overall quality, ensuring parts meet specifications.
Overmolding vs Insert Molding
FAQs
What is overmolding used for?
Overmolding is used to combine multiple materials into a single part to improve grip, durability, protection, and appearance. It is commonly applied to ergonomic handles, seals, housings, and reinforced components.
What materials can be overmolded together?
How is overmolding different from insert molding?
What are typical lead times for overmolding?
Can overmolding be used for low-volume production?
What tolerances can be achieved with overmolding?
Do you provide DFM feedback before tooling begins?
Is overmolding suitable for complex part designs?
Does overmolding reduce assembly costs?
Yes, overmolding combines multiple functions into a single part, eliminating secondary assembly steps and reducing overall manufacturing costs.
Which industries commonly use overmolding services?
Overmolding is widely used in automotive, medical devices, electronics, robotics, automation, and consumer products due to its functional and aesthetic benefits.
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