Chapter Outline
Humans are quite good at subtractive manufacturing. For millennia, we have been removing material to make things, such shaping tools by striking stones together or carving pieces of wood to form a useful or artistic object. We developed these techniques through trial and error, and passed knowledge first from generation to generation and eventually across cultures. Later, humans learned how to isolate metal from rock, how to form it and combine it into alloys to meet increasingly advanced needs. As you likely know, the history of humanity is often described in terms of these materials and knowledge – the Stone Age, the Bronze Age, the Iron Age. Most of the items you see and use every day – from pens to keyboards to cooking pots to contact lenses – are created based on techniques that, even if highly complex, are considered to be “legacy” manufacturing. As humans have many times in our history, we have developed a new series of techniques, known as advanced manufacturing. Additive Manufacturing is one of those forms of advanced manufacturing, distinguished by the process of building an object one layer at a time.