Now that you know how printing works and what materials are used, let's take a look at the different types of 3D printing technologies and how they are different. All of their methods are always changing, and as new techniques get better, they're bound to change as well. At the moment, there are three main ways that 3D printers work.
It is chemically based and depends on the interaction of lasers and light-sensitive chemicals. These chemicals are set up so that when they come into contact with UV laser light, they change from liquid to solid. The UV laser is moved across a thin surface of the chemical liquid by the 3D printers that employ this technique to create the desired object. Each layer is lowered into the chemical liquid and thinly immersed as it solidifies. The UV laser continues to move across the liquid, creating additional solid layers, until the finished product is solidified and finished. The surface of the objects produced using the stereolithography method has proven to offer a very high level of finishing and detailing. The finished product is obtained by separating the solidified 3D object from the chemical pool in a single flow after the entire printing process has taken place in the chemical liquid. This was the first way to print in 3D, developed in 1983 by Charles Hull.
Common Applications: Injection mold-like polymer prototypes; jewelry casting; dental applications.
Materials: Photopolymer resins (castable, transparent, industrial, biocompatible, etc.)
Strengths: Smooth surface finish, fine feature details.
Advantages of SLA printing:
The SLA printing service can make parts with very precise measurements and lots of small details.
The SLA model has a high level of surface finish.
SLA rapid prototyping can use unique materials, such as transparent, flexible, cast resin, etc.
The time it takes to finish printing is short.
Disadvantages of SLA printing:
Components made with SLA prototyping are often fragile and not good for functional applications.
"Fused Deposition Modeling" is based on the use of molten material that hardens as it is layered onto the print surface. As the molten material comes out of the printer head, it builds up the 3D design layer by layer. This process will keep going until the product is finished. This method also uses molten foods, like cheese and chocolate, to make food with complicated shapes. This type of 3D printer is one of the least expensive ones on the market. These kinds of printers use plastics like ABS and PLA, as well as organic polymers that break down over time. In a slightly different version of this printer, the plastic additives can also come from spools of plastic filament. This method is called "Fused Filament Fabrication" because the plastic additives come from spools of filament. This type of printer can use almost any material that has a creamy consistency, like clay, silicone, chocolate, cheese, frosting, cement, and even some metals.
Common Applications of FDM: Electrical housings, form and fit testing, figs and fixtures, investment casting patterns, etc.
Materials: Plastic filament (PI-A, ABS Nylon, PET, PETG, TPU, ASA, pc, HIPS, Carbon Fiber, and many more.)
Strengths: Lowest cost 3D printing method, a wide range of materials.
Advantages of FDM 3D printing:
The most cost-effective way to make custom thermoplastic parts and prototypes is to use the FDM printing service.
Because FDM printing technology is so common, the FDM delivery cycle is short (as fast as the next day).
There are many thermoplastic materials to choose from that can be used for prototyping and some functional applications that are not for sale.
The speed of formation is fast, and the post-processing is easy.
Disadvantages of FDM 3D printing:
The surface is relatively rough.
You can't print in more than one color at the same time with monochrome printing.
FDM has the worst accuracy and resolution of all the 3D printing methods, so it can't be used to make parts with a lot of small details.
Selective Laser Sintering (SLS) uses powdered materials that are glued or heated together between layers to make the 3D shape that is wanted. This method is called "Selective Laser Sintering" (SIS), and it combines traditional 3D printing with lasers (instead of UV light). By adding to the stereolithographic method, SLS replaces the chemical pool with a powdered base material and the UV light with a powerful laser. By using both methods together, SLS printers can make things out of all kinds of plastics, as well as ceramics and metals. It has been shown to be a cost-effective alternative to other 3D printers when using materials like polystyrene, nylon, glass, metals, and other unusual ones. The powdered materials from these sources are easy to join together with a laser, and when the 3D printing project is done, the extra material can be used again. It also gets rid of the need to use support, which makes the whole process much faster and easier.
Common Applications of Selective Laser Sintering (SLS): Functional parts, complex ducting (hollow designs), low-run part production.
Materials: Thermoplastic powders (Nylon 6, Nylon 11, Nylon 12, etc.), metal powders (steel, titanium, aluminum, cobalt, etc.), and ceramic powders.
Strengths: Functional parts, excellent mechanical properties, complex geometries.
The advantages of SLS 3D printing technology:
SLS rapid prototyping parts have excellent isotropic mechanical properties.
It does not require a support structure. One of the best things about SLS printing should be that the suspended layer in the lamination process can be directly supported by powder that hasn't been fused.
The use of materials in SLS 3D printing is high. It is the most common material utilization rate for 3D printing technologies because there is no need for support or a base. Even though the price is low, it is more expensive than SLA.
Disadvantages of SLS 3D printing technology:
At the moment, only industrial SLS systems are widely used, so the delivery time is longer than with other 3D printing technologies (such as FDM and SLA).
Large planes and small holes are hard to print with SLS because they tend to warp and get too much processing.
The surface of parts that are made with SLS is rough.