What is Rapid Prototyping, Rapid Manufacturing, & 3D Printing?
Rapid prototyping is slowly revolutionizing manufacturing. That's fitting - there is nothing rapid about rapid prototyping. First introduced in the 1980s, rapid prototyping encompasses a number of rapid prototyping technologies that use Computer Aided Design (CAD) files to build parts from the bottom up, one thin layer at a time (0.1mm to 0.5mm thick), using lasers or adhesives to bond liquid or powdered plastic or metal. This is also known as additive manufacturing or solid freeform fabrication, and doesn't require machining or tooling. This is a sea change from traditional manufacturing, where subtractive techniques (milling, turning, grinding) are generally used to form parts.
Of course, in high volume, traditional manufacturing dictates the creation of tooling (dies for metal, molds for plastic) that eliminates the need for subtractive manufacturing. Here too, rapid prototyping is transforming the landscape. Dies and molds are being manufactured with rapid tooling techniques, significantly curtailing the long lead time and cost of tooling manufacture.
Yes, rapid tooling is faster than old school tool and die work, but for single parts making, rapid prototyping is generally much slower. With some technologies, a part the size of a human head can take 24 hours to fabricate. Why bother? Answer: There is little to no set up and formerly impossible part geometries are now feasible. Back to that head - try doing that on a Bridgeport mill. Want a one-off prototype to test fit and function? Want a cube with a hollow core? Want to fabricate objects from multiple materials? Want to engage in mass customization, where consumers dictate design? Want to manufacture parts on demand as they are ordered? Now you're talking.
The true misnomer of rapid prototyping is not the rapid part, but the term prototyping. Increasingly, these technologies are being used not for product development, but for manufacturing. As the equipment becomes further refined to fabricate parts faster and cheaper, expect this transformation of manufacturing to accelerate. And don't be surprised if the term "3D printing" takes on more general use than it currently does, and becomes the new industry standard.