Into solid: Compression Molding
This process is kinda similar to injection molding in terms of having two halves of the mold (male and female) enclosed to form the basic structure of the final form. However, instead of having a large cylinder transferring melted plastic pellet into the mold, this time the “plastic pellets” (or rather a block of raw unformed material) of the object are placed directly on top of the female mold, and both halves of the mold are transferred with heat at a specific melting point of the plastic. The male part will have a certain amount of pressure being applied in a downward position that would melt and sandwich the raw material. The plastic piece will start to melt and fill into the empty part of the mold, thus creating the final form of the desired part. Once the plastic dries out, the finished component is removed from the female mold with the aid of a small pin that pushes it upward.
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Despite of offering a large selection of different thickness settings, it is rather limited in terms of the variety of shapes. As long as thermoset plastic could find its place in regards to the flexibility and ease of forming and production, compression molding is also good for producing large parts that requires thick walling.
