3D printing has been taking leaps in development, since starting its journey from the early stages of the 1950s to the first properly working prototypes in the 1970s.
That journey hasn’t been all smooth, but for what it’s worth, there are many patented 3D printing technologies that propelled this art to a whole new level. They all use 3D printer software to create the model for printing. Let’s go over those technologies and see how they work.
Fused Deposition Modeling (FDM)
FDM printers are widely available on the market. If you are looking for a 3D printer for your home, this is the one to get. FDM printers are built on the principle of material extrusion. This 3D printing technology entails a thermoplastic filament that is fed to a heating nozzle.
The latter melts the filament and then deposits it onto a platform, according to the model designed on the 3D printing software. The nozzle is supported by a rigid frame that allows the nozzle to move along smoothly and deposit the filament without delays.
Most popular filaments for FDM printers include ABS, PLA, PET, PVA, wood filament, etc.
FDM printers are the cheapest out there and can be used as a great learning tool for both adults and children. They are relatively easy to use and produce great results. So it’s the best 3D printer type for educational environments and for home.
This is a general principle of 3D printing that includes a few technologies: Stereolithography (SLA) printing, Masked Stereolithography (MSLA), and Digital Light Processing (DLP). We’ll discuss their differences in a minute, but first, let’s see what unites them as different branches of the same general principle.
If FDM Printing melts the filament and deposits it on a platform to build the model layer by layer, the process of Vat polymerization uses photosensitive resin in a vat and a light that selectively cures, or transforms the resin, making it solid.
As we’ve mentioned already, a Stereolithography 3D printer uses photopolymer resin. SLA printers use a system of mirrors situated on the x and y axes. They reflect the UV laser, which selectively ‘solidifies’, or cures the resin.
The platform is situated on the surface of the liquid resin and gradually rises, as the model builds up. By the end of the stereolithography process, you will have the platform and the complete model underneath it built up-side-down.
Masked Stereolithography (MSLA)
The process of MSLA printing uses a LED array to cure the resin. It shines the UV light through an LCD screen, which displays the layer slice like a mask.
This is where the process got the name. Naturally, the displayed layer is composed of pixels. Thus the pixel size is crucial for the granularity of the print.
Digital Light Processing (DLP)
As a part of the same group of vat polymerization techniques, DLP also uses light to cure photopolymer resin. It is very similar to SLA printing but with a few differences. DLP printing uses a digital light projector to flash the whole layer of the model at once. This way, as the layer is flashed all at once, there’s no need to cure the resin by making pinpoint flashes on the cross-sections.
Powder Bed Printing (PBP)
Powder bed printing (PBP) is a process where a thermal energy source selectively fuses powder particles to create a solid object. It uses thermoplastic powders as 3D printing materials and it’s capable of achieving quite sophisticated geometric objects with excellent mechanical properties.
Selective Laser Sintering (SLS)
This is one of the printing processes that uses the general principle of Powder Bed Fusion. For SLS printing, a bed of thermoplastic powder is heated to a temperature just below the melting point. The recoating blade deposits a thin layer of powder, then a laser fuses the particles selectively to create the next layer. After each layer is scanned, the blade will again deposit some fresh powder for fusing the next layer. Each step of the process is repeated until the full object is manufactured.
Selective Laser Melting (SLM) and Direct Metal Laser Sintering (DMLS)
Powder bed printing is also possible for metals, which Selective laser melting is all about. The process is much like SLS, but if SLS uses thermoplastic powder as material, SLM uses metal. DMLS doesn’t actually melt the metal particles. It heats them up to the point where changes can happen on a molecular level. SLM, on the other hand, melts the powder completely with a laser, to fuse the metal powder and create a homogenous model. PArts created through SLM and DMLS are later heat-treated for durability.
Electron Beam Melting (EBM)
This technology is different from other powder bed printing techniques. It uses a high-energy electron beam to induce fusion between the metal powder particles. Compared to SLM and DMLS, EBM creates models at a higher speed. EBM creates parts in a vacuum, and the process can only be used with conductive materials.
Material Jetting (MJ)
This is a way of 3D printing, where drops of material are deposited on the build platform and then cured on the spot. The material is either photopolymer or wax, both of which cure when exposed to light. A standard inkjet printer delivers the ink in a single layer. MJ printers do the same in multiple layers built upon each other.
The most notable advantage of this type of printing is speed. Plus, it can produce multiple objects at the same time, as long as they are spaced and lined correctly.
Drop on Demand (DOD)
DOD technology uses two inkjets simultaneously. One is for the build material itself, which is much like wax in its properties. The second inkjet is for the support material, which is dissolvable. To ensure a perfectly flat surface, the DOD technology uses a fly-cutter that flattens the surface after each layer is deposited.
Laminated Object Manufacturing (LOM)
During LOM Printing, layers of adhesive-coated paper, plastic, or metal are glued to each other. Then a laser cutter or a knife cuts the final model out of those layers. While it’s not the most popular method of 3D printing today, it is surely one of the most affordable techniques.
The list above is a general guide to 3D printing techniques, no if you want to learn more about each of them, hopefully now you’ll feel more confident to do so. 3D printing is a rapidly expanding and developing technology that has lots more in store for us!