Starting from a 3D model, a part is built by cutting it into thin horizontal slices via the stereolithography 3D printing machine’s software. A support structure is created where needed in order to deal with overhangs and cavities. This machine then uses a computer controlled laser to draw the bottom cross section onto the surface of a liquid polymer that hardens where struck by the laser. The part is then lowered to a depth corresponding to the section's thickness. The next cross section is then drawn directly on top of the previous one. This is repeated until the part is finished. The supports are removed manually after the product is taken from the machine.