3D printers build a model layer by layer. Any 3D model can be sliced like a cucumber. The printer creates a solid layer one on top of another till a model - or in this analogy, a cucumber - appears.
Fusion deposit machines (FDM) use spools of wire like thermo-plastic, heating it to a paste at the extruder and depositing it on a surface (print bed). Electric step-motors move the extruder around, usually using belts and runners. PLA, ABS, PET even PVA are all polymers which FDM machines can use. PLA plastic has the added advantage of being a bioplastic usually made from cornstarch, it is compostable at industrial facilities and has a low toxicity profile.
Stereolithography (SLA) printers often have a vat of UV sensitive resin which a UV image is projected on - one layer at a time. These machines allow us to print highly detailed models quickly. However, the print beds are small and the resin is both costly and often a hazardous material to work with.
Generally, a printer’s resolution, or print quality, is limited by the layer height of the printer. Our FDM machines have a height of 0.1mm and our SLA machines have a layer height of 0.05mm. Overhangs in models are secured to the build plate with removable structures call support.
3D printers now come in a vast range of types. Some use wet cerment, others using cake icing, some use a welder as a hotend and metal as material. They all take a long time to print anything though…