Some companies combine additive manufacturing (AM) and subtractive methods to take advantage of what each process does best. For example, the time needed to build this stainless-steel electronic housing was reduced from 52 weeks for an entirely cast part to 3 weeks by machining the base housing and building up the vertical details directly on the housing using AM. (Source: Sandia National Labs)
Eventually, there will be 3D printers that can employ multiple methods of additive/subtractive fabrication along with different materials. Some home-based desktop printers can already use multiple materials (i.e.: ceramics and thermoplastics) and it surely won't be long before multiple printing methods will be incorporated.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.