There are several different types of plastic molding techniques and methods used to create a wide range of plastic components and parts, with plastic injection molding standing out as the most technically advanced procedure. Custom plastic injection molders implement cutting-edge tools and equipment to create complex parts in an efficient and effective manner. However, that doesn’t mean you should not be familiar with other, less advanced molding methods. 

What are the different types of plastic molding?

Today, plastic is one of the most widespread materials in the world. It is used for manufacturing parts for a wide range of applications – from industrial to medicinal. The majority of these components are made with a cost-effective and efficient process of injection molding. However, there are also other plastic molding methods that have their merits. 

Blow molding

In essence, blow molding is very similar to traditional glass blowing. A machine inflates a plastic parison with air until it achieves the desired shape. This process directly blows the heated plastic into its final form. After cooling, the machine ejects the end-product from the mold. 

This type of plastic molding is useful for creating simple, identical hollow containers with thin walls. That is why it’s mostly used for manufacturing plastic bottles, as well as drums and large storage containers. However, blow molding is unable to create more intricate components. 

Compression molding

Compression plastic molding consists of placing heated plastic into heated molds, closing the mold, and compressing plastic into desired shapes. The machine then removes the completed part from the mold after cooling. The curing, which is the name for the heating process, allows the end-product to retain its shape and structural integrity. 

Compression molding uses high-strength parts to manufacture components and parts for a wide range of applications – from the clothing industry to the automotive industry. However, it is still unable to achieve the level of complexity capable with plastic injection molding.

Extrusion molding

Extrusion molding is an interesting plastic molding process because it extrudes melted plastic materials into the die. This is a unique process, as the die shape, and not the shape of the mold, determines the final shape of the finished product. 

Extrusion molding is suitable for producing parts that require continuous lengths and identical cross-section. Also, it is often used to manufacture hollow-formed components, such as straws, pipes, and tubes. Also, it can create different shapes, such as U or T shapes, but it cannot produce exceedingly complex parts. 

Rotational molding

Rotomolding uses rotational movements combined with extremely high temperatures for coating the inside of the mold and forming the final shape of the component. As the mold rotates, it cools down, which allows the machine to eject the finished product. 

This type of molding is good for making large and hollow containers that have a single section, for example tanks. However, this is a slow process and does not allow for fast, mass production of specific parts. 

Injection molding

Plastic injection molding is by far the most versatile molding process currently available. It is fast, cost-effective, and can create various parts of varying size, shape, and complexity. The process sounds simple – injecting melted plastic into a steel mold before cooling and ejecting the finalized product. 

However, this process is as complex as the mold – the more intricate the part, the more difficult it is for operators to adjust all the necessary parameters to ensure an excellent end-product. Also, the choice of plastic resin plays an important role in the properties of the finished component. 

Plastic injection molding is a reliable solution for manufacturing very large volumes of consistent and precise components of varying complexity. It is also more cost-effective and efficient than the alternatives, making it the most suitable plastic molding process. 

Which custom plastic injection molder manufactures high-quality parts and components?

There are different types of plastic molding, but injection molding is the superior option, as there are many parts and components plastic injection molding can manufacture either through cold runner or hot runner molding. If you’re not that familiar with the process of plastic injection molding, you should definitely learn more about the most common terminology connected to this type of plastic molding before hiring a custom plastic injection molder. 

When you start looking for potential plastic injection companies, know that there is one that stands apart – Wunder Mold. We have created a detail-oriented injection molding process that incorporates all the customer requirements during part design to produce the components per your exact specifications. We will carefully choose the adequate resin to give your product the properties you need. Call (707) 448-2349 or send an email to