The material chosen for the project will determine which printing methods are most suitable. Among these, the most commonly used techniques for each group of materials are described next.
If you want to use Plastic or Alumide:
- Fused Deposition Modeling (FDM) Technology: is at the very entry of the market as it mainly used by individuals. It is probably the most popular printing method due to the number of printers available on the market. FDM is an affordable 3D printing process compared to other 3D printing technologies. This process works by material being melted and extruded through a nozzle to 3D print a cross section of an object each layer at a time. The bed lowers for each new layer and this process repeats until the object is completed. Layer thickness determines the quality of the 3D print. Some FDM 3D printers have two or more print heads to print in multiple colours and use support for overhanging areas of a complex 3D print.
- SLS Technology : Laser sintering is a 3D printing technique consisting of the fabrication of an object by melting successive layers of powder together in order to form an object. The process most notably facilitates in the creation of complex and interlocking forms. It is available for Plastic and Alumide.
If you want to use Resin or Wax
- Stereolithography (SLA) : uses a vat of curable photopolymer resin. The build plate descends in small increments and the liquid polymer is exposed to light where the UV laser draws a cross section layer by layer. The process is repeated until a model has been created. The object is 3D printed by pulling the object out of the resin (bottom up), which creates space for the uncured resin at the bottom of the container and can then form the next layer of the object. Another method is to 3D print the object by pulling it downward into the tank with the next layer being cured on the top.
- Digital Light Processing (DLP) a projector is used to cure photopolymer resin. This is very similar to the SLA method except that instead of using a UV laser to cure the photopolymer resin, a safelight (light bulb) is used. Objects are created similarly to SLA with the object being either pulled out of the resin, which creates space for the uncured resin at the bottom of the container thus forming the next layer of the object, or down into the tank with the next layer being cured at the top.
Sculpteo uses DLP technology for Silver and Brass 3D printing. We 3D print a wax model first then, we use a lost-wax casting technique: a mould is made around the wax before it is melted and filled with silver, creating your object.
- Continuous Liquid Interface Production (CLIP) works by projecting a continuous sequence of UV images, generated by a digital light projector, through an oxygen-permeable, UV-transparent window below a liquid resin bath. The dead zone created above the window maintains a liquid interface below the part. Above the dead zone, the curing part is drawn out of the resin bath.
- MultiJet printers : Similar to Stereolithography, the high-quality PolyJet and MultiJet 3D printing processes use a UV light to crosslink a photopolymer. However, rather than scanning a laser to cure layers, a printer jet sprays tiny droplets of the photopolymer (similar to ink in an inkjet printer) in the shape of the first layer. The UV lamp attached to the printer head crosslinks the polymer and locks the shape of the layer in place. The build platform then descends by one layer thickness, and more material is deposited directly onto the previous layer.
If you want to use Metal
- DLP combined with the lost-wax casting technique allows objects to be printed in 3D. Sculpteo uses DLP technology for Silver and Brass 3D prints. First, we 3D print a wax model. Then, we use a lost-wax casting technique: a mould is made around the wax before it is melted and filled with silver, thus creating your object.
- Direct Metal Laser Sintering (DMLS) uses a laser as a power source in order to sinter metal powder by aiming a laser and tracing a cross section of the object layer by layer. Direct Metal Laser SIntering is similar to the selective laser sintering process.
- Electron Beam Melting (EBM) uses an electron beam as the power source instead of a laser to 3D print metal. An electron beam melts metal powder layer by layer within a high vacuum and can achieve full melting of the metal powder. This method can produce high-density metal parts thus retaining the material’s properties.
If you want to use multicolour
- Binder Jetting is popular since you can create detailed 3D prints with colour. An automated roller is used to spread a layer of powder onto the build platform. Excess powder is pushed to the sides and ensures that the bed is filled with a layer of packed powder. On a fast axis, the print heads apply a liquid binder and colour simultaneously to create a cross section of the object on the powder.
- Selective Deposition Lamination is a 3D printing process using paper. This process is similar toLaminated Object Manufacturing (LOM) rapid prototyping method. The process involves layers of adhesive coated paper (or plastic or metal laminates) that are successively glued together with a heated roller and cut to shape with a laser cutter layer by layer. A roller with the material moves each new sheet of material over the last and repeats the process until the object is completed.
- Triple-jetting technology (PolyJet) used in Stratasys Objet500 Connex3, is the most advanced method of PolyJet 3D printing. This technology performs precise printing with three materials and thus makes three-colour mixing possible. To know more about this technology, you can refer to PolyJet & Multijet