3D-printing is a new set of technologies which allows to create real solid objects from computer tridimensional models.
Models in the computer are „printed“ (maybe should we say „sculpted“?) in an extremely precise way on different materials (plastic, acrylic, ceramics, metal, sandstone…).
There are different types of 3D printers for different applications. The one we use more often for the musical instruments on this website works with a layer by layer system where polymer is solidified using a laser, but depending on the project several other technologies also come into play.
Just like in normal good-quality printing on paper, copies are indistinguishable from each other in practical therms.