There are many different ways to 3D print an object. But nearly all of them utilize computer aided design (CAD) files. CAD files must be translated into a “language,” or file type, that 3D printing machines can understand. Standard Tessellation Language (STL) is one such file type. CAD models must be broken up into layers before being printed in three dimensions. STL files “cut up” CAD models, giving the 3D printing machine the information it needs to print each layer of an object.
This is a great article from Digital Trends outlining the history of 3D printers (aka Rapid Prototyping Machines). It covers most of the important types of Machine available today. Some great video clips also found in the article that is worth a watch.
Three-dimensional objects may be produced by depositing repeated layers of solidifying material until the shape is formed. Any material, such as self-hardening waxes, thermoplastic resins, molten metals, two-part epoxies, foaming plastics, and glass, which adheres to the previous layer with an adequate bond upon solidification, may be utilized.
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