The bottom layer has hundreds or thousands of tiny intersecting liquid-handling channels, each about the width of a human hair (100 microns).

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These printers use something like a toothpaste tube of plastic or other material held vertically in an X-Y plotter that squirts out thin layers of tiny dots of material that build up, layer by layer, to produce a 3D replica of the computer-generated design.

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Each layer consists of an array of elements made of foil, which produce tiny electrical pulses whenever they are penetrated by specks of dust.

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