Thermoforming mold

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Mold, Thermoforming Tools that form pre-extruded sheets by means of temperature and vacuum and/or pressure. Generally made from aluminum, either cast or machined.

Types of thermoforming molds

Wood Patterns - wood patterns are generally the first stage to a thermoforming project. They are relatively inexpensive and allow the customer to makes changes to their design very easily. The number of samples that one is able to get from a wood pattern depends on the size of the part and the thickness of the material. Typically, wood patterns are used to gauge general functionality of both the part and the thickness of the material. Once the specifications of the part have been met, the wood pattern is then used to create a ceramic composite mold, or cast aluminum mold for regular production.

Cast aluminum Molds -Cast aluminum molds are cast at a foundry and typically have temperature control lines running through them. This helps to regulate the heat of the plastic being formed as well as speed up the production process. Aluminum molds can be male or female in nature and can also be used in pressure forming applications. The main drawback with this type of mold is cost.

Machined aluminum Molds - Machined aluminum molds are like cast aluminum except they are cut out of a solid block of aluminum using a CNC machine and some sort of CAD program. Typically machined aluminum is used for shallow draw parts out of thin gauge material. Applications may include packaging as well as trays. Again, cost is a significant factor with this type of tooling.

Composite Molds - Composite molds are a lower cost alternative to cast or machined aluminum molds. Composite molds are typically made from filled resins that start as a liquid and harden with time. Depending on the application, composite molds last a relatively long time producing high quality parts. Within the category of composite molds, the subset of "Ceramic" molds has consistently proven to be the most durable. While not temperature controlled, these molds can run nearly as fast as Cast or Machined aluminum, yet at a substantially lower price point. Suitable for all but the highest volume production and strictest tolerances. Source: Ceramic Thermoforming Tools

Advantages

As molds for thermoforming have only one side (the other side of the product is created by air pressure) and as undercuts are not allowed, these molds are relatively easy to manufacture.

Applications

Such moulds are used to shape plastic sheet into such end products as interior liner shells for refrigerators.