3D printing works by converting a 3D model into a set of computer-generated instructions to incrementally build up a part layer by layer. Most 3D printing technologies use this same basic premise to manufacture 3D printed items.
What Are the Types of 3D Printing?
The majority of 3D printers work by building up a component layer by layer. The difference often lies in the form of the raw material and the way the machine fuses each layer to make up the final part. There are three main 3D printing types:
- Stereolithography (SLA)
Stereolithography converts a liquid photopolymer into a solid part. It traces a high-powered laser in the shape of the 2D cross-sectional image of the part. This light polymerizes the plastic layer onto the bed plate. Then the build plate moves slightly, a new coat of photopolymer is applied, and the laser proceeds to solidify it to the previous layer. - Selective Laser Sintering (SLS)
Selective laser sintering starts by placing a thin layer of powder on the build plate. A laser then traces out the cross-section of the part and melts the plastic or metal powder so that it can harden into a solid shape. A new layer of powder is then placed over the previous one and the process is repeated. To learn more, see our full guide on SLS 3D Printing. - Fused Deposition Modeling (FDM)
Plastic for FDM machines is delivered in the form of filament on a spool. This filament is pushed through a cavity that is hot enough to melt the plastic. The plastic is then pushed through a nozzle which deposits it one layer at a time to build up a solid part.