3D Printing is actually a pretty basic process.
Get a tube of toothpaste and try to form a cube with it on the bathroom bench. To make the cube you have to keep squeezing the paste out into a long trail that goes back and forwards on top of other layers slowly building the object.
- The machine is your hand and the material is the toothpaste.
- The object is an image in your brain and the rest of the brain coordinates itself with nerves, muscles and bones to keep producing the trail of paste until the cube is made.
In a modern 3D Printer.
- The machine is a gadget with pulleys and motors to keep an extrusion head moving in three dimensions: X, Y and Z axis. The material to make the object is a thermoplastic fed from a roll down into a heated extrusion head that melts the plastic and lays it on top of the previous layer as it goes around and around making the object.
2. The object started in someones brain somewhere (maybe yours) and was sketched into a drawing program called a CAD. Then like your brain, another program called a slicing program constructed a way for the machine to make the object in one very long thin fibre. In the case of a hull it can be over a kilometer long and take many hours.