Attività

Have you ever wondered how the latest styles of automobiles came to be?

The next time you drive or ride in a car, you’ll notice much of the interior consists of plastic. The molding around the entertainment center, the steering wheel, and more all consist of plastic.

Take a look at the exterior. The headlights and bumpers? In many models, they consist of, you guessed it, plastic.

But plastic automotive molding is relatively new.

Automobiles before the 1970s used metal for everything. This made them heavy and clunky.

It wasn’t until the 1940s and 1950s when the plastics started booming. By the 1970s, vehicles started using lightweight plastic for decorative elements. It wasn’t until the 1980s that some exterior elements started to use plastics.

The 2000s welcomed the use of plastics for structural parts making vehicles lighter and more fuel-efficient.

Once melted, the plastic enters an injector which pushes it into a shaped cavity. It fills the cavity and sits until it cools and hardens. After it hardens, you can remove it from the metal cavity and use it for its intended purpose.

A similar process works with most polymers, resins, foams, and silicone rubber. The process and machine used will change a little depending on the size of the part you’re molding and material used.

Structural automotive foam, which you can find inside the door and side panels, uses a foam mold. Resin is the primary material, but other plastics can work as well. It’s even lighter than most plastics and can be just as durable. 

Sometimes when you’re choosing what manufacturing method to use, the requirements for dimensions, materials, and specifications make conventional production processes too expensive. Milling, turning and drilling to machine a block with openings and chamfers that will hold bearings or other components is complex and difficult. Of course, you can cast parts, but the up-front cast molding investment only makes sense when fabricating parts in high volumes. 

What if you’re working on a prototype in its early design stages and you only need to fabricate only one or two parts? Milling and turning take a lot of time and waste a lot of material, but electrical discharge machining services (EDM) can be a more efficient solution. EDM is a manufacturing process where material is removed from a workpiece by applying a series of current discharges between two electrodes separated by a dielectric bath liquid.