Overmolding Service

High-quality custom overmolding services for prototypes and on-demand production parts. Rapid Tooling Production as fast as 2 weeks.

STEP | STP | SLDPRT | IPT | PRT | SAT files

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High Quality Parts

Owing certified factories, conducting in-process inspections and dimensional verification after production, guarantee the custom molded parts are consistent in quality regardless of the complex shape with high precision.

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Fast Lead Time

With certified domestic factories and a strong supply chain system, we accelerate the product development cycle and bridge the production of your overmolded parts as fast as possible.

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Engineering Support

Working with our experts having 10+ years of experience in the injection molding industry, efficiently complete a turnaround from prototyping to production.

What is
Overmolding?

Overmolding is an advanced plastic injection molding technique used to combine two or more thermoplastic materials into a single, unified part. This process begins by injecting the first thermoplastic, known as the substrate, which forms the core structure of the product. A second material, called the overmold, is then injected either around or onto the substrate, bonding with it as the materials cool. The overmolding technique enhances the durability, functionality, and aesthetics of products, commonly used in high-volume production for industries that require high-performance parts, such as automotive, medical devices, and electronics.
 
At Termite Precision, we specialize in custom plastic overmolding to boost the functionality and visual appeal of your components. Our expert team and advanced technology deliver seamless bonds between materials, ensuring top-quality results.
 
Contact us today for a detailed quote on custom overmolded parts tailored to your needs.

Overmolding Process

Crucial for mass production, involves machining, and assembling durable molds from steel or aluminum to ensure precise and repeatable part geometries.

 

  • Aluminum and steel injection mold.
  • Achieves detailed geometries.
  • Ideal for mass production.

Overmolding improves product functionality and aesthetics by fusing different materials into one part, adding features like soft grips and multi-color designs for enhanced usability

 

  • Improves strength and lifespan.
  • Combines different materials seamlessly.
  • Offers color and texture options.

Insert molding integrates metal or other materials into plastic parts during molding, enhancing strength and reducing assembly time for components with embedded features.

 

  • Reduces assembly steps.
  • Enhances component durability.
  • Lowers production expenses.

Insert molding integrates metal or other materials into plastic parts during molding, enhancing strength and reducing assembly time for components with embedded features.

 

  • Reduces assembly steps.
  • Enhances component durability.
  • Lowers production expenses.

Overmolding
Tooling Solutions

Prototyping

Rapid Tooling

Get easy design feedback and validation through superior quality prototype tooling. Create small batches of plastic molded parts with excellent injection molding prototypes. We excel at manufacturing prototype molds within days to ensure you perform functional tests and validate market interest. 

Our molds with steel cavities and cores typically have a shot life of 1,000 to 5,000 shots and can be manufactured within two weeks.

Production

Production Tooling

We create high-quality production molds for high-volume plastic parts production. With high-strength, durable tool steel material, our production tooling is suitable for producing hundreds of thousands of parts. We can vary materials and construction methods according to your unique requirements.

Our high performance steel tool is capable of enduring up to 10,000 shots, and generally parts can be produced within 3 weeks.

Termite Precision's 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.

There is no secondary polishing or grinding, which means that our parts will display marks from the tooling process.

materials

Materials for
Overmolding

We offer a broad range of thermoplastic and thermoset materials, each selected for its performance characteristics and suitability for different applications.

Plastics
ABS

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

PC

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 (Acrylic)

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

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

PA (Nylon)

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

PE

 

Polyethylene is lightweight and has high resistance to impact, widely used in packaging and containers.

PE Black

PE White

PEEK

PEEK is renowned for its high temperature resistance and strength, often used in aerospace and medical implant manufacturing.

PEEK Beige(Natural)

PEEK Black

PP

Polypropylene is tough, has excellent chemical resistance, and is used for automotive parts, containers, and in packaging.

PP Black

PP White

PP+GF30 Black

HDPE

HDPE is known for its high strength-to-density ratio, resistance to impacts, and is used in making bottles and corrosion-resistant piping.

HDPE Black

HDPE White

HIPS

HIPS is easy to machine and offers good dimensional stability and impact resistance, suitable for prototyping and modeling.

HIPS Board White

LDPE

LDPE is soft, flexible, and used in applications where heat sealing is required, such as in tubing and plastic bags.

LDPE White

PBT

PBT is a strong, rigid plastic that is heat resistant and commonly used in electrical components and casings.

PBT   Black

PBT Milky White(Natural)

PPA

PPA offers high heat resistance and stiffness, ideal for automotive and electrical applications that require durability at high temperatures.

PAI

PAI has exceptional thermal and chemical stability, used in high-performance parts in aerospace and automotive sectors.

PAI Brown

PET

PET is strong, resistant to moisture and chemicals, and widely used in food containers and textile fibers.

PET Black

PET White

PET+GF30 Black

PET+GF30 White

PPS

PPS features outstanding chemical and heat resistance, suitable for automotive and aerospace components.

PPS Black

PPS White

PPS+GF30 Black

PPS+GF30 White

PS

Polystyrene is lightweight and easy to machine, used for models, prototypes, and low-strength applications.

PS Transparent

PVC

PVC is robust, cheap, and has good chemical resistance, used in plumbing, medical devices, and cables.

PVC Grey

PTFE (Teflon)

PTFE is known for its outstanding chemical resistance and low friction, making it perfect for non-stick coatings and gaskets.

Teflon (PTFE) Black

Teflon (PTFE) White

UPE

UPE has extremely long chains, resulting in a very tough material, ideal for high-abrasion applications like lining chutes.

UPE Black

UPE White

Bakelite

Bakelite is heat resistant and electrically non-conductive, perfect for electrical insulators and radio and telephone casings.

Bakelite Black

Bakelite Orange

FR-4

FR-4 is a flame-resistant material, primarily used in the electronics industry for circuit boards and insulators.

FR-4 Aqua Green

FR-4 Yellow

Overmolding
Capabilities

Termite Precision’s custom overmolding services ensure the creation of plastic parts that look and perform better. Our production line consists of an overmolding injection molding process that allows us to combine several different materials into one, ensuring you get superior-quality products.

StandardsDescription
Standards Maximum Part SizeDescription 200×400×100mm
7.87×15.75×3.94 in.
Standards Manimum Part SizeDescription 2×2×2mm
0.08×0.08×0.08in
Standards Substrate Wall ThicknessDescription From 0.5 to 3mm
From 0.20 to 0.12 in.
Standards ToleranceDescription +/- 0.025 mm
+/- 0.00098 in.
Standards RadiiDescription 0.1mm
0.0039in.
Standards DepthDescription 100mm from the parting line
3.94 in. from the parting line
Standards Mold ValidationDescription Provide T0, T1, T2 samples before mass production
Standards Inspection and Certification OptionsDescription First Article Inspection, ISO 9001, ISO 13485
Standards Lead TimeDescription From mold making to sample delivery: 15-45 business days

Advantages of Overmolding

Overmolding enhances product durability and functionality by integrating different materials, offering improved grip, aesthetics, and cost-effective assembly.

 

  • Improved Design and Creation of Custom Plastic Parts: Overmolding capabilities ensure the creation of custom plastic-plastic or metal-plastic product combinations with a high dimensional quality.
  • Better Product Performance: Overmolded parts are of excellent quality because of their two-material advantage for various applications.
  • Increased Shelf and Aesthetic Appeal: The overmolding process can be optimized with many materials and surface treatment processes to improve the aesthetic quality of the product.
  • Better Shock Absorption and Overall Durability: Overmolding also offers improved shock absorption due to the plastic resin addition, ensuring longer shelf life and excellent resistance against impacts.
  • Lower Production Costs: Since overmolding eliminates post-assembly phase of production, it speeds up the production process and reduces overall manufacturing cost.

Applications of Overmolding

The injection overmolding process is compatible with a wide variety of materials, ranging from plastics to metals. This process helps produce custom prototypes and production parts for various applications depending on your requirements. Several industries find valuable uses for overmolding services.

 

  • Surgical Instruments: Overmolding meets the precision and safety requirements of the medical industry. The ability to combine plastics and metal materials ensures the efficient creation of surgical devices, equipment housing, catheters, syringes, and more.
  • Electrical Applications: Using thermoplastic elastomer as an overmold material makes the process useful for electrical components. Custom-made overmolded parts, like electrical outlet covers, gaskets, etc., are made to withstand harsh conditions, making them last longer.
  • Hardware Tools: The functional advantages of overmolding make it an outstanding process for making pliers, screwdrivers, hammers, wrenches, pocket knives, and more. The process improves the grip of these tools, making their application more efficient.
  • Household Items: The overmolding technique generally improves functional performance like grip, cleanliness, and ease of use. It also enhances vibration dampening, chemical resistance, and more. This makes them useful for household items like kitchen utensils, toothbrushes, pens, shampoo bottles, etc.

Overmolding
vs Insert Molding

While there are various similarities between overmolding and insert molding, there are also certain differences you must note. Here’s a video to explain the vital differences between these valuable processes.

FAQs

1. What is the overmolding process?
Overmolding is a specialized injection molding process that creates a single product by combining two or more materials. This technique involves two main steps. Initially, a rigid substrate—such as metal or plastic—is injected into a mold to form the core of the product. Once the substrate is set, a second material, typically a flexible thermoplastic elastomer (TPE), is overmolded onto the substrate.
This outer layer not only enhances the product’s comfort and grip but also provides additional functionality and aesthetic appeal. The choice of materials allows manufacturers to tailor the properties of the final product, achieving desired qualities like durability, softness, and color.
Overmolding is widely used across various industries, including automotive, consumer electronics, and medical devices. Its ability to simplify assembly and improve product performance makes it an attractive option for creating innovative designs that meet diverse market needs.
Overmolding and insert molding are two advanced manufacturing processes used in plastics to enhance product performance and design.
  1. Process Definition: Overmolding involves adding a second layer of material over an existing molded part, often combining different materials to achieve specific properties like improved grip or enhanced durability. In contrast, insert molding incorporates a pre-formed component, such as a metal insert, into the mold before the plastic is injected, creating a strong bond between the two materials.
  2. Application: Overmolding is typically used for ergonomic products, like handles and grips, where a softer material enhances comfort. Insert molding is favored in applications requiring structural integrity, such as automotive components, where metal parts need to be integrated into plastic housing.
  3. Design Flexibility: Overmolding allows for creative design combinations and aesthetics, while insert molding is focused on functionality, ensuring the insert is securely held within the molded part.
Overmolding is a flexible manufacturing technique where a secondary material is molded over an existing base material, enhancing functionality, appearance, or user comfort. Common materials used in overmolding include:
  1. Thermoplastics: These are frequently used due to their excellent flexibility and durability. Examples include Polypropylene (PP), which offers chemical resistance, and Polyethylene (PE), known for its toughness.
  2. Thermoplastic Elastomers (TPE): These materials combine the characteristics of rubber and plastic, providing elasticity and a soft touch. Styrenic block copolymers (SBC) are a popular choice for their superior flexibility and adhesion.
  3. Silicone: Known for its heat resistance and biocompatibility, silicone is ideal for medical devices and consumer goods requiring flexibility and durability.
  4. Polyurethane (PU): This material is valued for its cushioning properties and abrasion resistance, making it suitable for applications in automotive and footwear industries.
  5. Rubber: Often used for its excellent grip and vibration-damping properties, rubber is a preferred choice for handles and grips in various products.
Overmolding applies a secondary material over a primary substrate to improve functionality and aesthetics. Key principles include:
• Material Compatibility: Ensuring the primary and secondary materials bond effectively to maintain durability and product integrity.
• Design Optimization: Designing parts with features like undercuts for better adhesion and ensuring smooth flow and coverage of the secondary material.
• Process Control: Managing injection temperature and pressure to fully fill the mold and avoid defects.
Design considerations are critical for achieving a successful overmolding process and high-quality products:
• Material Selection: Choose primary and secondary materials that are compatible in adhesion, flexibility, and thermal properties to ensure a strong bond and prevent delamination.
• Geometry and Design Features: Incorporate features like undercuts, ribs, or grooves to improve mechanical interlocking and adhesion, reducing the risk of peeling or separation.
• Mold Design: Optimize the mold for proper material flow, ensuring complete coverage of the substrate. Account for gating and venting to prevent air traps and ensure even filling.
• Tolerances and Clearances: Account for thermal expansion and shrinkage during cooling to maintain dimensional accuracy and meet product specifications.

Yes, silicone can be overmolded, but it takes careful planning. It’s often paired with thermoplastics to boost functionality or aesthetics. Strong adhesion depends on compatibility between the silicone and substrate, and surface prep like cleaning or priming may be needed. Precise temperature and molding control are also key to avoid damaging the silicone. When done right, silicone overmolding creates durable, high-performance parts for many applications.

Absolutely. EPDM works great for overmolding with thermoplastics. Its flexibility, weather resistance, and ability to handle extreme temperatures make it perfect for outdoor and automotive use. Proper adhesion is crucial, so cleaning or treating the EPDM surface can help. Controlling temperature and pressure during molding ensures the EPDM stays intact. Done correctly, EPDM overmolding produces strong, reliable parts for tough environments.

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