WhatsApp: +86 19166273143 | emma.tan@tkbkl.com


Home - Blog - Creating a Chair Mould for Injection Molding

Creating a Chair Mould for Injection Molding

Date: 2023-8-27

Injection molding is a widely used manufacturing process for producing plastic products. It involves injecting molten plastic into a mold cavity, allowing it to cool and solidify, and then removing the molded part. In order to produce high-quality plastic chairs using injection molding, a well-designed chair mold is essential. This article will discuss the steps involved in creating a chair mold for injection molding.

Step 1: Designing the Chair

The first step in creating a chair mold is to design the chair itself. This involves considering factors such as the chair\’s size, shape, and functionality. The designer must also take into account potential issues that may arise during the injection molding process, such as draft angles, wall thickness, and gating locations. Computer-aided design (CAD) software is typically used to create a 3D model of the chair, which serves as a blueprint for the mold.

Step 2: Determining the Mold Type

There are two main types of molds used in injection molding: the two-plate mold and the three-plate mold. The choice between these two types depends on factors such as the complexity of the chair design and the desired production volume. A two-plate mold consists of a stationary half and a moving half, which open and close to eject the molded part. A three-plate mold includes an additional plate, which allows for the creation of undercut features in the chair design.

Step 3: Creating the Mold Base

The mold base is the foundation of the chair mold and provides support for all other components. It is typically made from high-quality steel and includes features such as support pillars, guide pins, and ejector pin holes. The mold base is precision-machined to ensure accurate alignment of the mold components.

Step 4: Building the Mold Inserts

The mold inserts are the parts of the mold that create the shape and features of the chair. They are typically made from hardened steel or aluminum and are precision-machined to achieve the desired level of detail. The inserts are designed to fit into the mold base and can be easily replaced or modified if necessary.

Step 5: Adding Cooling Channels

During the injection molding process, it is crucial to maintain a consistent temperature in the mold cavity. Cooling channels are added to the mold inserts to facilitate the rapid cooling of the molten plastic. These channels are strategically placed to ensure even cooling and prevent warping or shrinkage of the chair.




Step 6: Designing the Gating System

The gating system controls the flow of molten plastic into the mold cavity. It consists of a sprue, runners, and gates. The sprue is the main channel through which the plastic is injected, while the runners distribute the plastic to different areas of the mold. The gates are the entry points into the mold cavity. The design of the gating system is crucial for achieving a balanced and uniform filling of the mold.

Step 7: Assembling and Testing the Mold

Once all the mold components are ready, they are assembled into the mold base. The mold is then tested to ensure that it functions properly and produces high-quality parts. This may involve running trial injections to check for any defects or issues. Adjustments can be made to the mold design or process parameters as needed.


Creating a chair mold for injection molding requires careful planning and design. Each step, from designing the chair to assembling the mold, plays a crucial role in ensuring the production of high-quality plastic chairs. By following these steps and paying attention to detail, manufacturers can create molds that meet their specific requirements and produce chairs that are both functional and aesthetically pleasing.

Latest News