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 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.
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.
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 relatively a long time producing high quality parts. For larger production runs, however, it is not recommended that composite molds be used.
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.
Process: Vacuum forming, Plug assist forming, Vacuum snapback, Billow forming, Free forming, Pressure forming, Drape forming, Stretch forming, Matched die forming, Inline thermoforming, Twin sheet forming, Mechanical thermoforming
Equipment: Thermoforming machine, Thermoforming mold
See also: Injection molding • Blow molding • Plastic welding • Plastic extrusion • Rotational molding
