Over Moulding

What is over moulding?

Over moulding is where you take an initial plastic component and put it into a second moulding process. This second mould tool adds a second softer material directly to the initial component, like a seal or soft touch outer surface.

How can over moulding reduce costs?

Typically, over moulding removes an assembly procedure, a finishing process and often reduces the inventory required for the finished product.

How and where over moulding could be used

There are many applications but listed below are the most common reasons for over moulding:

Soft touch – to avoid irritation if the product is worn

Grip – to make the product easier to handle

Aesthetics – combining 2 colours and different textures

Strength – combining two polymers to provide greater molecular strength

Seal – to provide an air or water tight seal

Why is over moulding better?

There are three major advantages of using over moulding for manufacturing plastic parts and components.

1. Detailed Features and Complex Geometry

Over moulds are subjected to extremely high pressure, which means the plastic within the over mould is pressed harder against the original plastic component compared to any other secondary process. It’s also possible to add a large amount of details into the design of the original part and/or over moulded element.

2. High Efficiency to Save Manufacturing Costs

The actual over moulding process is very quick compared to any alternative methods for adding a secondary process. The high production output rate makes plastic injection over moulding more cost effective and efficient. This is because automation allows for making precise and accurate components time after time, reducing human error or the inconsistencies of a manual assembly process.

3. Enhanced Strength

Using plastic injection over moulding, it’s possible to use complimentary products to add greater molecular strength to the part. For example, giving a part which needs to be soft to the touch, a robust inner core, making it both strong and durable.

Enhances your product and keeps component assembly lean

Using the plastic injection moulded components with over moulding also ensures the parts manufactured hardly require any work after the production. This is because the parts have more or less a finished appearance after they are ejected from the secondary ‘over mould’ process.

Today, plastic injection moulding is an environment-friendly process. The scrap plastic generated during the production process is reground and re-used. Hence, the process generates very little waste.