2 Shot Injection Moulding

To further enhance the value and aesthetic appeal of products, customers often look to over-mould plastic to rubber or double-inject two different plastics together through two-shot moulding.

These two methods of production, including multi-shot techniques, allow a part to be produced in two different material types or colours without the need for additional, often expensive assembly operations.

For over-moulding, generally a TPE thermoplastic rubber is used to co-mould onto a plastic material, usually ABS or PC, in a two-tool stage process, creating a stronger bond. This is used on many instrument cases where the customer wants to produce a case that has a durable feel and to offer further impact protection to the plastic shell.

The 2 shot or double injection moulding process allows for two separate hard plastics to be moulded simultaneously. The method used depends very much on the design of the part and also the quantities of production that will be required. This is sometimes used to produce high usage plastic key caps with the legend being a different colour plastic rather than being printed.

Capabilities for our double injection process range from 125T to 380T machines.

What is 2 Shot Injection Moulding Process?

2 Shot Injection Moulding, also known as two-shot injection moulding, is a sophisticated manufacturing process that involves injecting two different plastic materials into a single mould to create a single, multi-material component. This technique is highly valued in the plastics industry for its ability to produce complex parts with enhanced functionality and aesthetic appeal.

How It Works

The process begins by injecting the first material into the mould to form the substrate part. Once this initial shot has solidified, the mould rotates or shifts to a second position where the second material is injected over or alongside the first. This second injection bonds with the first, creating a powerful molecular bond between the two materials. The entire process is automated, ensuring high precision and efficiency.

Benefits of 2 Shot Injection Moulding

1. Elimination of Secondary Assembly: One of the primary advantages of this method is that it eliminates the need for secondary assembly operations. By combining two materials in a single cycle, manufacturers can save time and reduce labour costs.
2. Colour Variety: The ability to use multiple colours in a single part without additional painting or labelling increases the aesthetic appeal of the final product. This is particularly beneficial for consumer electronics and other products where appearance is crucial.
3. Material Pairing: The process allows for the pairing of different materials, such as rigid plastic with softer thermoplastic elastomers, to create products with soft-touch surfaces or enhanced grip. This flexibility in material selection enables the production of parts with diverse functionalities and improved performance.

By leveraging the capabilities of standard injection moulding machines and carefully selected materials, 2 Shot Injection Moulding provides manufacturers with the tools needed to create high-quality, complex geometries with minimal manual intervention.

Benefits of Over Moulding and Double Injection Moulding Processes

Customers often choose overmolding and the overmolding process along with double injection moulding for several key factors. Here are the key benefits:

• No Need for Secondary Assembly: Both methods integrate multiple materials or colours in one moulding process, eliminating the need for additional assembly steps. This not only reduces manufacturing time but also cuts down on labour costs.
• Improved Aesthetics and Durability: By combining different materials, these processes enhance the visual appeal and robustness of the final product. This is especially advantageous for consumer electronics and products where appearance and longevity are critical.
• Enhanced Impact Resistance: Over-moulding, in particular, can add a layer of impact-resistant material, such as TPE, to a rigid plastic base, providing extra protection and durability to the finished assembly.
• Multi-Colour or Multi-Material Product Design: The ability to incorporate multiple colours or materials into a single part without additional finishing processes allows for greater design flexibility and innovation, meeting diverse market demands.

These benefits make over-moulding and double injection moulding highly desirable for producing complex parts with enhanced functionality and aesthetic appeal, all while optimising production efficiency.

Over Moulding vs. 2 Shot Moulding – What’s the Difference?

When deciding between over-moulding and 2-shot moulding, it’s essential to understand the specific requirements of your project. Both techniques offer unique advantages and are suited for different applications.

Over Moulding

Over moulding typically involves using a TPE thermoplastic rubber in combination with a base material such as ABS or PC, starting with the first injection to create the initial part. This process is conducted in two stages, where the initial plastic part is created and then a secondary, softer material is moulded over it. Over-moulding is ideal for products that require additional grip or impact resistance. A common real-world example is instrument cases, where the over-moulding process adds a durable, protective layer to the rigid plastic shell, enhancing both feel and impact protection.

2 Shot Moulding

In contrast, 2-shot moulding involves the simultaneous injection of two hard plastics within a single moulding cycle, transitioning to the second mould for the subsequent material. This method is perfect for applications where multiple colours or materials need to be integrated using the same tool without additional assembly steps. An example of this is the production of plastic key caps, where the legend can be a different colour from the base, achieved during the same moulding process.

Choosing the Right Technique

• Use Over Moulding when you need a soft touch surface, enhanced grip, or impact resistance, especially in products like protective cases or grips.
• Opt for 2 Shot Moulding when your project requires hard plastics with multiple colours or integrated functionalities, such as in consumer electronics or automotive components.

By understanding the key differences and applications of over-moulding and 2-shot moulding, manufacturers can make informed decisions to optimise production efficiency and meet specific material requirements.

Materials and Machinery Capabilities

At the heart of our two-shot injection moulding process is our robust machinery, with capabilities ranging from 125T to 380T. This range allows us to accommodate various project sizes and complexities, ensuring precise control over the moulding process. Our advanced machines are equipped to handle a wide array of plastic materials, including TPE, ABS, and PC, which are commonly used in the industry for their excellent material compatibility and performance.

Our commitment to technical excellence is further demonstrated by our ability to maintain tight tolerances throughout the injection moulding processes. This precision ensures that each moulded part meets the exact specifications required for high-quality production. Additionally, we offer extensive customisation options, allowing us to tailor the manufacturing process to meet the specific design and functional needs of our clients.

By leveraging our state-of-the-art machinery and expertise in material selection, we deliver high-quality, complex parts with enhanced product quality and aesthetic appeal, establishing our technical credibility in the plastics industry.

Applications of 2 Shot and Over Moulding

The versatility of 2-shot injection moulding and overmolding makes these processes highly relevant across various industries, offering innovative solutions for complex part production. Here are some key applications:

Consumer Electronics

In the consumer electronics sector, 2-shot moulding is frequently used to create products with enhanced aesthetic appeal and functional integration. For instance, electronic device casings can be produced with multiple colours and textures in a single cycle, providing both visual appeal and ergonomic benefits without additional assembly steps.

Automotive Components

The automotive industry benefits significantly from over-moulding and 2-shot moulding techniques, allowing for the creation of durable components from two plastic materials. These processes allow for the creation of durable, multi-material components using compatible materials such as dashboard panels, switches, and handles. By combining rigid plastics with softer materials, manufacturers can produce parts that offer both strength and comfort, improving the overall driving experience.

Medical Devices

Medical devices often require precise, high-quality components that can withstand rigorous use. 2-shot injection moulding is ideal for producing parts with intricate designs and multiple materials, such as surgical instruments and diagnostic equipment, leveraging a robust bonding process. Over-moulding can also add a layer of grip or cushioning to medical tools during an automated cycle, enhancing their usability and safety.

Keyboards/Keypads

In the production of keyboards and keypads, 2-shot moulding is utilised to create keys with distinct legends and tactile feedback. This process allows for the integration of different colored plastics, ensuring that the legends remain visible and durable over time, even with frequent use.

By leveraging the capabilities of 2-shot and over-moulding, we can meet the diverse needs of various industries, producing high-quality, functional, and aesthetically pleasing products.

Why Choose Rubbertech for 2 Shot Injection Moulding?

Selecting the right partner for your 2 shot injection moulding needs is crucial to the success of your project, considering several factors. At Rubbertech, we stand out in the industry due to our extensive experience, commitment to quality, and exceptional customer support. Here’s why you should choose us:

Experience and Expertise

With years of experience in the plastics industry, Rubbertech has honed its skills in the art of two-shot injection moulding. Our team of experts possesses in-depth knowledge of the moulding process, material compatibility, and mould design, ensuring that we can tackle even the most complex projects with precision and creativity. We pride ourselves on our ability to produce high-quality, multi-material components that meet the specific requirements of our clients.

Quality Control and Consistency

At Rubbertech, quality is at the forefront of everything we do. Our robust quality control systems ensure that each moulded part is produced to the highest standards. We utilise state-of-the-art machinery and advanced techniques to maintain consistency across all production runs, delivering reliable and durable products that exceed expectations. Our commitment to quality means that you can trust us to deliver parts that enhance your product’s performance and aesthetic appeal.

Turnaround Time and Support

We understand the importance of meeting deadlines and keeping your project on track. Rubbertech is dedicated to providing fast turnaround times without compromising on quality, especially when working with two or more materials. Our efficient processes and streamlined workflows allow us to deliver your products promptly. Additionally, our customer support team is always available to assist you at every stage of the manufacturing process, ensuring a smooth and hassle-free experience.

By choosing Rubbertech for your dual-shot and 2 shot injection moulding needs, you gain a partner who is committed to excellence, innovation, and customer satisfaction. Let us help you bring your vision to life with our superior moulding solutions.

Please contact us with your requirements.