Insert molding is used in conjunction with other die-casting processes to add fastener components to normally die-cast metal parts before the parts are permanently cast in place. Inserts are normally placed automatically or manually onto die-cast molds cast into those molds. Die-cast metal components need to be precise and exact or they may not fit properly or may break at a later date. To ensure that the insert molding fits correctly and holds the die-cast part securely, special equipment must be employed. There are many reasons why you need to learn about molding.
The process of inserting molding involves three basic steps which involve: molds, die-cast pieces to be inserted, and molten zinc or iron being added to the hot molten metal. These three steps of the insert molding process have different approaches depending on the type of molding that will be used. For example, there are two types of molding – pressed and multi-shot. Press molding molds require only one shot; however, multi-shot moldings use more than two shots to achieve the same effect. The advantage of multi-shot moldings over press moldings is that there are usually many identical shots made with the same amount of molten metal.
The method used to cast the insert molding will depend on the type of part that will be formed as well as the amount of material to be used. Press moldings use a flat plate to deposit the metal onto the substrate. When the metal is still hot it is forced down into the substrate and shapes are formed. This type of molding may produce several identical parts or many parts that are slightly different. Depending on the specifications required by the client, some parts may need to be engraved or specially designed.
The advantage of automatic insert molding is that the machine can perform the necessary operations in a short period of time. There are three basic types of automatic inserts, namely, manual insert molding, semi-automatic insert molding, and fully automatic-insert molding. Manual inserts require an operator for each operation. Semi-automatic inserts are automatic but only require a trigger for each action. Fully automatic inserts are the most expensive because they are able to cast a higher number of identical parts.
A semi-automatic insert molding machine uses a plastic handpiece that is manually maneuvered in order to trigger the molding equipment. When a part is desired, the handpiece is maneuvered to the appropriate position and this triggers the machine, which deposits the needed metal into the part. There is no manual labor involved in this type of insert molding process. The downside is that parts that are not intended to come off during the manufacturing process may not be properly costed.
Fully automatic inserts are available on the market today and these machines are able to cast hundreds of identical parts. This technology also allows for manual adjustment of the plastic parts during the production process. Although these machines are more costly than the semi-automatic types, they provide greater value because they are able to create more accurate and detailed parts.