Whether or not you're familiar with plastic injection molding, you use items fabricated with it every day. The majority of plastic products, anything from toys to the keys on your computer keyboard to museum display cases, are manufactured using injection molding. While often done on a large industrial scale, injection molding can be just as useful for custom-designed small-run or individual pieces.
The first step of injection molding is to make a mold. A designer creates the original model; either a physical construct or a computer design can also be used, in the shape of whatever plastic piece is required. A mold is then constructed out of metal from the design using precision machinery. Molds can be as simple as two matching halves, but often come in multiple pieces to accommodate different configurations of pieces.
To cast a piece, the mold is placed in an injection molding machine, which clamps the separate parts together. Melted plastic, usually in the form of special pellets fed into the machine from a hopper and melted down, is then injected into the mold at high pressure. The cold metal of the mold quickly hardens the plastic into the shape of the mold; it may be additionally cooled with a coolant such as water. Finally, when the plastic has fully solidified, the mold is opened to remove the piece. With most types of modern molding polymers, the pieces come out with a smooth surface and nearly ready to go, though the plastic can be polished, painted or laser-etched afterwards, if a more advanced finish is desired.
Injection molding has many advantages. Because the plastic is injected at such high pressures, it's forced into every contour of the mold. This allows for injection molded pieces to be made with extreme detail and precision, so intricate parts can be made to exact specifications. Multiple types of plastics can be injected at the same time, allowing for complex designs, and fillers can be added to increase the plastic's strength and durability.
Once a mold is made, the molding process itself is quite fast, so pieces can be produced quickly as well as accurately, and the process can be automated for efficiency.Also, since molds can be constructed in almost any shape from unique designs, it's easy to make parts to order, be it custom pieces for equipment, commercial displays or any other items. See this website for more information on a plastic shop in Vista.
