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Custom Overmolding Services

  • Guaranteed Bond Integrity | Eliminate Leaks & Product Failures
  • Seamless Scaling from Prototype to Production | Accelerate Your Time-to-Market
  • Certified for Demanding Industries | Navigate Medical, Auto & Electronics Compliance with Confidence

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Trusted by Engineers and Purchasing Leaders at the World's Most Successful Companies

15+Years in Business
250,000+Unique Parts Produced
8000+Customers Served
99.8%On-time Delivery
ISO9001:2015 Certified

Trusted bynumerous companies

ABB
BMW
Bombardier
Electrolux
FLIR
Google
I-Dent
Lamborghini
Tesla
ABB
BMW
Bombardier
Electrolux
FLIR
Google
I-Dent
Lamborghini
Tesla

LS Manufacturing has delivered reliable experience to over 28,000 customers by producing more than 250,000 complex parts

What is Overmolding?

What is Overmolding?

Solve Design & Assembly Challenges with a Unified Manufacturing Approach

Overmolding is an advanced injection molding process that permanently bonds multiple materials into a single, integrated component. It effectively addresses key manufacturing pain points by eliminating unreliable assembly methods and multi-part inventory management.

  • Part Consolidation: Combines rigid substrates with functional overmolds to eliminate secondary assembly and simplify supply chains.

  • Enhanced Performance: Provides superior grip, environmental sealing, and vibration dampening for demanding operating conditions.

  • Elevated User Experience: Delivers soft-touch interfaces and refined aesthetics for medical, automotive, and consumer applications.

By merging materials directly in-mold, overmolding creates more durable, reliable, and functional products while streamlining your production process. At LS Manufacturing, we ensure perfect material bonding to eliminate delamination risks and deliver high-performance components.

Overmolding Process Solutions

Select the optimal overmolding strategy to solve material performance gaps, simplify assembly, and enhance product value. Each LS Manufacturing process targets specific design and production challenges, delivering parts that combine materials with precision for superior performance.

Plastic over Plastic

Plastic over Plastic

Ideal for achieving flawless consistency and complex geometries in high-volume production. This process utilizes precision steel or aluminum molds to produce identical parts with exceptional detail and repeatability, solving the core challenge of defect-free mass manufacturing.

  • Precision molds for high-volume runs
  • Achieves detailed, complex geometries
  • Ensures part-to-part consistency
  • Ideal for consumer electronics & automotive
Rubber Over Plastic

Rubber Over Plastic

Enhance product usability, comfort, and sealing by integrating soft-touch materials. This process bonds rubber to plastic substrates seamlessly, adding ergonomic grips, environmental seals, and multi-material aesthetics without secondary assembly or adhesive failure.

  • Improves grip and ergonomics
  • Provides environmental sealing
  • Combines materials without adhesives
  • Extends product lifespan
Plastic Over Metal

Plastic Over Metal

Unify metal's strength with plastic's design freedom to create robust, integrated components. Through insert molding, metal parts are encapsulated in plastic during a single cycle, eliminating fasteners, reducing assembly, and strengthening the final assembly.

  • Reduces assembly steps and part count
  • Enhances structural integrity
  • Eliminates fasteners and adhesives
  • Lowers total production cost
Rubber Over Metal

Rubber Over Metal

Combine durability with protection for components in harsh environments. This insert molding process bonds rubber directly to metal, creating parts that dampen vibration, resist impact, and provide secure, sealed interfaces for demanding applications.

  • Dampens vibration and absorbs impact
  • Protects metal from corrosion & wear
  • Creates sealed, durable interfaces
  • Essential for automotive & machinery

Ready to select the right overmolding process?

LS Manufacturing

Overmolding Tooling Solutions

PROTOTYPING

Rapid Tooling

Compress your development cycle and de-risk material compatibility. LS Manufacturing’s rapid overmolding tooling delivers true multi-material prototypes in weeks, not months. Test the bond, function, and feel of your design with production-grade substrates and overmolds, validating performance before committing to high-cost production tooling.

Our prototype tools are engineered for 1,000 to 5,000 cycles, providing a reliable, cost-effective path to perfect your overmolded design and secure market confidence.

PRODUCTION

Production Tooling

Launch with certainty. Our production overmolding tools are built for uninterrupted, high-volume manufacturing. We engineer robust, multi-material molds with high-strength steels to ensure perfect bond integrity and consistent part quality over hundreds of thousands of cycles.

Designed for longevity and precision, our production tooling withstands over 1,000,000 cycles, delivering durable, high-performance overmolded parts on a reliable timeline.

Overmolding Material Selection

LS Manufacturing partners with innovators across medical, automotive, electronics, and industrial sectors to deliver precision overmolding solutions that combine materials for superior performance, ergonomics, and reliability. From startups to global brands, we transform complex multi-material challenges into production-ready successes.

PLASTICS

ABS
ABS

ABS

ABS provides impact resistance, structural strength, and ease of modification, making it ideal for housings, prototypes, and functional components that require durability and cost-effectiveness.

Color:
BeigeBlackWhite
Subtypes:ABS Natural (Beige), ABS Black, ABS White, ABS+PC Blend, Flame Retardant ABS, Anti-static ABS
Available Finish:As machined, Sand blasting, Painting, Texture coating, Vapor polishing
Price:$$
Lead Time:About 5 business days

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Overmolding Finishes

Achieve flawless, consistent surface finishes on overmolded components through advanced mold-finishing techniques that ensure repeatable results across production cycles. LS Manufacturing delivers integrated surface solutions for multi-material parts—from soft-touch textures to high-gloss surfaces—applied directly at the tool level, with secondary operations available for specialized requirements. Our expertise ensures perfect surface harmony between substrate and overmold materials for applications requiring both aesthetic appeal and functional performance.

Matte Finishes

Create uniform, non-reflective surfaces that enhance grip and conceal fingerprints on overmolded components. LS Manufacturing achieves consistent matte textures on both substrate and overmold materials through controlled mold finishing processes, ensuring perfect surface continuity across material transitions.

  • Dual-Material Blasting: Precision media blasting applied to specific mold areas for coordinated texture on both rigid and flexible materials

  • Transition Optimization: Seamless texture blending at material intersection points for visual and tactile consistency

  • Surface Roughness Control: Maintains specified Ra values (0.5-20 µm) across different material types

  • Typical Applications: Tool handles, medical devices, consumer electronics where soft-touch areas meet rigid structures

Matte Finishes

Overmolding Design Guidelines

Eliminate design risks and production delays for your multi-material components. The following LS Manufacturing guidelines are engineered to solve common overmolding challenges—ensuring strong material bonds, flawless cosmetics, and cost-effective manufacturability from your first prototype.

Overmolding Design Guidelines

Maximum Part Size

US

20 in. x 32 in. x 8.5 in.

Metric

508 mm x 812.8 mm x 216 mm

Volume

US

65 cu. in.

Metric

1,065,400 cu. mm

Depth

US

4.5 in. from parting line

Metric

114 mm from parting line

US

Up to 8.5 in. if parting line bisects part

Metric

Up to 216 mm if parting line bisects part

Projected Mold Area

US

180 sq. in. (Thermoplastic)

Metric

116,100 sq. mm (Thermoplastic)

US

50 sq. in. (Silicone/LSR)

Metric

32,260 sq. mm (Silicone/LSR)

Critical Design Considerations

•Material-Dependent Geometry: Part height and undercuts are limited when using silicone or LSR overmolds. Deep parts require a reduced footprint to ensure proper flow and bonding.

•Minimum Volume Requirement: The smallest feasible part volume is0.03 cu. in. (49.2 cu. mm) to maintain process stability and material performance.

•Machining & Resin Tolerances: For thermoplastic substrates, we maintain a machining tolerance of±0.003 in. (0.076 mm). Including material variation, the total tolerance is no less than0.002 in./in. (0.002 mm/mm).

•LSR-Specific Tolerances: When liquid silicone rubber is the overmold material, expect adjusted tolerances of0.025 in./in. (0.025 mm/mm) due to its higher shrinkage and flexibility.

Partner with LS Manufacturing to design overmolded parts that are built for performance, aesthetics, and scale.

Overmolding Customer Success Stories

LS Manufacturing partners with innovators across medical, automotive, electronics, and industrial sectors to deliver precision overmolding solutions that combine materials for superior performance, ergonomics, and reliability. From startups to global brands, we transform complex multi-material challenges into production-ready successes.

Drug Delivery Pen: Safety and Ergonomics in One Shot
Medical Devices

Drug Delivery Pen: Safety and Ergonomics in One Shot

A medical device manufacturer needed a safe, intuitive injection pen for patient self-administration. LS Manufacturing delivered a two-shot overmolded solution combining a clear PC barrel for dose verification with a non-slip TPE grip. The design integrated bold, tactile dose indicators and a slip-resistant surface, improving usability for patients with limited dexterity while maintaining drug integrity and sterility.

40%Improved Usability for Elderly Patients
100%Passed ISO 10993 Biocompatibility
Read Full Case Study
Smartwatch Band: Comfort Meets Durability
Consumer Electronics

Smartwatch Band: Comfort Meets Durability

A wearable tech leader required a hypoallergenic, comfortable watch band that could withstand daily wear and sweat exposure. We engineered a silicone overmold seamlessly bonded to a flexible nylon substrate, creating a breathable, skin-friendly band with integrated lugs for secure attachment. The one-piece design eliminated mechanical fasteners, enhancing comfort while surviving 50,000+ flex cycles.

60%Faster Assembly vs. Traditional Bands
0Skin Irritation Complaints
Read Full Case Study
EV Battery Connector Seal: Weatherproof Power Transfer
Automotive

EV Battery Connector Seal: Weatherproof Power Transfer

An automotive supplier needed a high-voltage connector that could withstand harsh underhood conditions. LS Manufacturing overmolded a silicone seal directly onto the PBT connector housing, creating a permanent IP67-rated seal that maintained integrity from -40°C to 150°C. The solution survived vibration, thermal cycling, and fluid exposure while simplifying assembly.

100%IP67 Seal Reliability
70%Reduced Assembly Steps
Read Full Case Study
Professional Drill Handle: Vibration Damping for All-Day Use
Tools & Equipment

Professional Drill Handle: Vibration Damping for All-Day Use

A power tool manufacturer sought to reduce operator fatigue in heavy-duty applications. We developed a triple-material solution: a fiber-reinforced nylon core overmolded with soft TPE grip zones and hard TPU impact shields. The optimized ergonomic pattern provided secure grip in oily conditions while damping vibrations by 30% compared to standard handles.

30%Vibration Reduction
200%Grip Life in Oily Conditions
Read Full Case Study
Premium Blender Lid: Silent Operation with Perfect Seal
Home Appliances

Premium Blender Lid: Silent Operation with Perfect Seal

An appliance brand needed a leak-proof blender lid that reduced noise during operation. LS Manufacturing overmolded a food-grade TPE seal directly to a transparent SAN lid, creating a perfect jar seal that dampened motor noise. The solution passed 10,000 open/close cycles without leakage while meeting FDA food contact standards.

0Leakage Failures
15 dBNoise Reduction
Read Full Case Study
Chemical Sensor Housing: Durability in Corrosive Environments
Industrial

Chemical Sensor Housing: Durability in Corrosive Environments

An industrial sensor manufacturer needed a housing that could withstand harsh chemical exposure while providing clear status indication. We overmolded a chemical-resistant FKM flange onto a transparent polycarbonate body, creating a permanent bond that survived 5,000+ hours in corrosive fluids while allowing visual status monitoring.

5xChemical Resistance Life
100%Bond Integrity in Chemicals
Read Full Case Study
Advantages of Overmolding

Advantages of Overmolding

Overmolding represents the evolution in multi-material manufacturing, seamlessly combining different materials into integrated components that deliver enhanced functionality, durability, and user experience. This advanced process solves complex design challenges by strategically bonding materials to create superior products that single-material methods cannot achieve.

  • Enhanced Product Performance and Durability

    Create permanent bonds between materials that withstand extreme conditions and extend product lifespan through integrated material properties, eliminating mechanical failure points.

  • Superior Ergonomics and User Comfort

    Combine soft-touch surfaces with rigid substrates to provide comfortable, secure grips and intuitive interfaces that improve usability and safety.

  • Streamlined Manufacturing Efficiency

    Integrate multiple components in a single molding cycle, reducing assembly steps, labor costs, and supply chain complexity while maintaining quality consistency.

  • Advanced Environmental Protection

    Achieve inherent sealing against moisture, chemicals, and harsh environments without additional gaskets or seals, ensuring reliable performance.

Applications of Overmolding

Applications of Overmolding

When your product demands exceed single-material capabilities, overmolding delivers integrated solutions that enhance both functionality and user experience across diverse industries and applications.

  • Medical Devices and Surgical Tools

    Ergonomic grips and seals for surgical instruments, drug delivery devices, and diagnostic equipment requiring biocompatibility and sterilization resistance.

  • Automotive Controls and Systems

    Durable interfaces, sealed connectors, and comfortable touchpoints that withstand automotive environmental challenges.

  • Consumer Electronics and Wearables

    Water-resistant casings, non-slip surfaces, and integrated buttons for modern electronic devices and smart accessories.

  • Industrial Equipment and Tools

    Enhanced grips, shock absorption, and sealed housings for power tools, measurement instruments, and factory equipment.

  • Aerospace and Defense Components

    Lightweight, sealed controls and communication devices capable of performing in extreme operating conditions.

  • Consumer Products and Appliances

    Comfortable, durable interfaces for household items, personal care products, and kitchen appliances combining function with aesthetics.

Overmolding Quality Control

At LS Manufacturing, precision overmolding is supported by a rigorous quality management system that addresses the unique challenges of multi-material manufacturing. Our comprehensive approach ensures perfect material bonding, dimensional stability, and functional reliability throughout production cycles. LS Manufacturing's overmolding quality assurance integrates material science expertise with precision manufacturing controls, delivering multi-material components that excel in performance, durability, and reliability.

Material Compatibility and Process Validation

Quality begins with scientific material selection and process optimization. Our engineers conduct thorough compatibility testing to ensure optimal bonding between substrate and overmold materials. We validate material interaction parameters including adhesion strength, thermal expansion compatibility, and chemical resistance before production, establishing a foundation for durable multi-material components.

In-Process Monitoring and Control

Real-time monitoring maintains stringent standards during overmolding operations. Critical parameters including injection pressure, temperature profiles, and bonding conditions are tracked with precision controls. Automated vision systems inspect material interface integrity, while regular mechanical testing verifies bond strength and structural performance throughout production runs.

Comprehensive Final Validation

Every overmolded component undergoes rigorous final inspection to guarantee performance specifications. Our quality team conducts detailed assessments of bond integrity, interface quality, and functional performance. Advanced testing methods including peel tests, environmental aging, and micro-CT scanning deliver verified data, ensuring components meet the most demanding application requirements before shipment.

LS Manufacturing's overmolding quality assurance integrates material science expertise with precision manufacturing controls, delivering multi-material components that excel in performance, durability, and reliability.

Learn More

2000+

ISO 9001

Certified

Why Choose LS Manufacturing for Overmolding Services?

LS Manufacturing transforms complex multi-material challenges into production-ready solutions. Our expertise in advanced overmolding technologies delivers seamless material integration, superior bonding performance, and exceptional value from prototype development through high-volume manufacturing.

1

Proven Material Compatibility Expertise

Solve bonding challenges with scientific material selection and process optimization. Our material science team leverages extensive compatibility data to ensure perfect adhesion between substrates and overmolds, delivering reliable performance across diverse material combinations and environmental conditions.

2

Advanced Multi-Material Process Integration

Achieve complex geometries with precision tooling designed for multi-shot and insert molding. Our state-of-the-art molding systems with robotic automation ensure perfect material alignment, consistent bonding quality, and efficient production cycles for complex overmolded components.

3

Comprehensive Quality Assurance Protocol

Ensure product reliability with specialized testing methodologies for overmolded parts. Our quality system includes bond strength validation, interface integrity testing, and environmental stress testing, guaranteeing durable performance in demanding applications.

4

End-to-End Technical Partnership

Accelerate your product development with integrated engineering support. From DFM analysis focused on material transitions to production validation and supply chain management, we provide complete technical guidance throughout your overmolding project lifecycle.

5

Cost-Effective Production Optimization

Maximize value through efficient process design and material utilization. Our overmolding solutions eliminate secondary operations, reduce assembly costs, and minimize material waste, delivering superior economics without compromising quality or performance.

Latest News

Stay updated with the latest news and announcements from LS Manufacturing. Explore our latest articles below.

Overmolding VS. Insert Molding: Key Differences And Selection Guide
overmolding

Overmolding VS. Insert Molding: Key Differences And Selection Guide

1. Core Quick Reference: Overmolding vs. Insert Molding 2. Why Trust This Guide? Practical Experience From LS Manufacturing Experts 3. What Is Overmolding? How Does It Enhance Product Value By Combining Multiple Plastics? 4. What Are The Unique Advantages Of Insert Molding In Integrating Metal And Plastic? 5. What Is The Core Difference Between Overmolding And Insert Molding? 6. What Specific Product Goals Are Typically Achieved When Choosing Overmolding? 7. In What Situations Is Insert Molding The Optimal Solution? 8. How LS Manufacturing Reduced Assembly Costs For A Medical Client By 30% Through Insert Molding 9. What Are The Differences In Cost And Cycle Time Between Overmolding And Insert Molding? 10. Why Choose LS Manufacturing As Your Overmolding/Insert Molding Partner? 11. FAQs 12. Summary 13. Disclaimer 14. LS Manufacturing Team

blog avatar Gloria
Oct 08 2025
7 Properties of Nylon: Everything you Need to Know
overmolding

7 Properties of Nylon: Everything you Need to Know

1.Here’s What You’ll Learn 2.Why trust this guide? Practical experience from LS injection molding experts 3.How to Choose the Right Nylon for Your Project: A Simple Decision-Making Framework 4.In-depth analysis: 7 key properties of nylon 5.Practical case analysis: from customer needs to successful products 6.FAQ - Answers to all your questions about nylon 7.Summary 8.Disclaimer 9.LS Team

blog avatar Gloria
Jun 10 2025
What Materials Are Used in overmolding？
overmolding

What Materials Are Used in overmolding？

1.What is overmolding？ 2.What Materials Are Used in overmolding？ 3.What are the specific applications and materials of overmolding? 4.What are the applications of overmolding? 5.FAQs 6.Summary 7.Disclaimer 8.LS Team

blog avatar Gloria
Dec 23 2024
How Does overmolding work？
overmolding

How Does overmolding work？

1.What is overmolding？ 2.How Does overmolding work？ 3.What types of materials are used in overmolding? 4.What are the common applications of overmolding? 5.Overmolding vs Insert Molding 6.What are the design considerations for overmolding? 7.FAQs 8.Summary 9.Disclaimer 10.LS Team

blog avatar Gloria
Dec 20 2024
What is overmolding？
overmolding

What is overmolding？

1.What is overmolding？ 2.How does overmolding work? 3.What are the advantages of overmolding? 4.What are the disadvantages of overmolding? 5.What are the applications of overmolding? 6.What are the materials used in overmolding? 7.What is the difference between insert molding and overmolding? 8.FAQs

blog avatar Gloria
Dec 19 2024

Overmolding FAQs

Get Instant QuoteSee More FAQs

Overmolding is a precision injection molding process that bonds a secondary material (typically a flexible elastomer like TPE or silicone) over a rigid substrate (plastic or metal) in a single manufacturing cycle, creating an integrated multi-material component.

Common substrate materials include ABS, PC, Nylon, and metal inserts. Overmold materials typically consist of TPE, TPU, silicone (LSR), or other engineered elastomers. Material compatibility is validated by LS Manufacturing to ensure optimal bond strength.

Key benefits include enhanced ergonomics (soft-touch grips), improved sealing and waterproofing, increased impact resistance, vibration damping, aesthetic differentiation, and the consolidation of multiple parts into one integrated assembly.

We ensure adhesion through scientific material selection, substrate surface preparation (texturing, plasma treatment), precise temperature and pressure control during molding, and rigorous bond strength testing (peel tests, environmental aging).

Yes. Overmolding can create permanent, watertight seals (up to IP68/IP69K) by bonding elastomers directly to rigid housings, eliminating the need for separate gaskets. This is ideal for consumer electronics, automotive sensors, and outdoor equipment.

Prototype lead times range from 2–4 weeks, depending on complexity. Production lead times typically range from 4–8 weeks, including mold fabrication, sampling, and qualification. Expedited options are available.

Overmolding is widely used in medical devices, consumer electronics, automotive interiors, industrial tools, and wearables—any application requiring enhanced durability, user comfort, sealing, or aesthetic refinement.

Our quality system includes material compatibility testing, in-process monitoring of molding parameters, 100% visual inspection, bond strength validation (peel/adhesion tests), dimensional verification via CMM, and environmental resistance testing.

Yes. We regularly combine these processes to encapsulate metal inserts, connectors, or electronic components within an overmolded elastomer layer, providing environmental protection, strain relief, and enhanced usability in a single operation.

Cost depends on part size, material combination, volume, and tooling complexity. While tooling costs are higher than single-shot molding, overmolding reduces assembly labor, part count, and improves product value—delivering strong ROI, especially at medium to high volumes.

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