3D printing is a logical extension of the idea of developing models and prototypes by more automated methods in which product designers make their own rapid prototypes, in hours, using sophisticated machines similar to inkjet printers.
A 3D printer essentially works by extruding molten plastic through a tiny nozzle that it moves around precisely under comp uter control. It prints one layer, waits for it to dry, and then prints the next layer on top. A typical 3D printer is very much like an inkjet printer operated from a computer. It builds up a 3D model one layer at a time, from the bottom upward, by repeatedly printing over the same area in a method known as fused depositional modeling (FDM). Working entirely automatically, the printer creates a model over a period of hours by turning a 3D CAD drawing into lots of two-dimensional, cross-sectional layers—effectively separate 2D prints that sit one on top of another, but without the paper in between. Instead of using ink, which would never build up to much volume, the printer use thermoplastics (plastics that melt when you heat them and turn solid when you cool them back down), and typically one called ABS (acrylonitrile butadiene styrene). ABS is perfect for 3D printing. For one thing, it's a solid at room temperatures and melts at a little over 100°C (220°F). For another,it's a whiteishcolor chemicals in paint yellow color in its raw form, but pigments (the ) can be added to make it virtually any color at all.
