- Bright Mind Team
The 3 Most Popular 3D Printing Technologies in 2019
Updated: Aug 6, 2019
There is no doubt that 3D printing has revolutionized many industries in the past 5 to 10 years. Chances are you have already seen many cool videos on social media of all sort crazy stuff being made by 3D printers! There are so many different types of 3D printers for many different applications and it almost seems impossible to get your head around all of them! Dont worry, we got your back; in this article we will simplify 3D printing technologies for you and discuss them under 3 categories; FDM, SLA, & SLS.
So what is 3D printing anyway?
Simply put: 3D printing is when a machine manufactures a 3 dimensional object by adding material layer by layer to build that object.
See the following image:
If you want to use a 3D printer to manufacture a simple dome design for example (like in the image above), your 3D printer's software will slice the dome design to layers, and then the printer will start adding layers of material to manufacture (3D print) the dome looking object.
All 3D printers work with this same principle. However, different 3D printers add these layers using different methods. The method the 3D printer use to add the layers on top of each other to create the 3D object is what differentiate 3D printing technologies.
As mentioned at the beggening of the article, the 3 most popular 3d printing technologies are FDM, SLA, & SLS. What does these sdfsdf stand for though?:
1) FDM: Fused Deposition Modeling
2) SLA: Stereolithography Apparatus
3) SLS: Selective Laser sintering
Dont be intimated with these scary names! Most of people remember and use just the initials (FDM, SLA, SLS).
Lets discuss each of these 3D printing technologies, understand their advantages and disadvantages, and put them in table for compassion:
1) FDM: Fused Deposition Modeling:
FDM 3D Printing Working Mechanism:
FDM 3D printers are pretty much the fathers of 3D printing; it all started with them! As the name emplies, Fused Deposition Modeling means that the printer deposits the layers of the material and these layers gets fused on each other to create the desired 3D model.
See the following image:
In FDM printers, filament (ropes of thin plastic) is pushed through a hot nozzle (1) as showed in the diagram above. The plastic softens/melts under the nozzle's high temperature (2), and then its deposited in an organized manner to create the desired 3D shape from layers (3).
Here is another diagram that describes how FDM 3D printers work, notice how the lastic filament here is pushed through a heated nozzle then deposited layer by layer to create an elephant shape.
FDM 3D Printing Materials:
FDM 3D printers usually use basic plastics solid plastics to 3D print. For example most of FDM 3D printers can 3D print with PLA, PETG, and ABS plastics. Its worth noting that PLA is not a real plastic, but its rather a composite made of .... and its one of the easiest materials to 3D print with FDM printers due to its low tempreture resistance. Its also worth noting that some FDM 3D printers are capable of 3D printing with more complex materials like Nylon and Carbon Fiber.
FDM Photo example
FDM Pros:
FDM 3D printers has been available in the market for a very long time now, and that helped in doping their prices significantly. There are also many variations of FDM 3D printers making them accessible to everyone. In addition to their low cost, FDM 3D printers also use relatively low cost materials. Add to all that, FDM 3D printing gives the user good control over the inner structure and density of the model being 3D printed.
FDM Cons:
FDM 3D printing is considered somewhat permetive these days; FDM 3D printing is relativly slow as parts are printed sepretly and independtly using one working nozzle (unlike other 3D printing techs where ...). FDM 3D printing is also mainly a low tech mechanical process that invloves heating and cooling of the printed parts. This lack of control in the 3D prinirng environment makes FDM 3D prints less predictable; Usuaslly FDM 3D printing is the 3d printing technology that has the height errors and print fails rate compared to other 3D printing technolgies. These errors include warpting, layer sperasion, layer adhesion failure, nozzle clogging, ..etc
2) SLA: Stereolithography Apparatus:
SLA 3D Printing Working Mechanism:
SLA 3D printers are relatively high tech 3D printers. Just like FDM printers, SLA printers also make 3D objects by adding layers of material on each other. However, SLA printers dont "deposite" layers of material, but rather "solidfies" liquid material is selected places to create a one solid layer. This solidification process is called curing. Sounds complicated? maybe a diagrame would help!:
Here how the SLA process goes: There is a comparatment of liquid (uncured) resin in the machine (2). This compartment position starts at the top of the printer and then gradually goes down ... yes SLA 3D printers print upsidown! The laser head (1) emmits a special type of light to hit the liquid resin in the resin tank in specific places. The liquid resin is made of a special material that solidfies (cures) when exposed to high concetratin of UV light. Therefor, the resin that is exposed to UV light from the laser head solifies and becomes a part of the 3D solid object. The process continues as the resin tank containing the liequid resin slowly moves away from the build plate (4) allowing the laser head to cure and solify more layers to build the 3D model layer by layer.
SLA 3D Printing Materials:
Whats going on in the diagram above is that the SLS 3D printer is using a laser head (1) to emit high energy beam. This high energy laser beam selectively hits regions of the raw powder (2) that is placed in the printer. The powder particles are a type of metal, and these particles fuses/weld to each other when hit with the high energy of the laser beam creating a solid layer of material. The build plate that is holding the powder gradually moves away from the laser head allowing it to fuse more layers of solid material to create a 3D solid object (3).
SLA Pros:
Unlike FDM 3D printers, SLA 3D printers dont use mechanical heated head for printing. Instead, it uses precise laser emitting head that is far more accurate than an FDM printer's nozzle. The laser head in SLA printers in not only more accurate, but it also moves much faster than the mechanical head in FDM printers. This makes SLA 3D printng more suitable for detailed printing than FDM printing. It also makes it faster specially if there more than one part to printed on the same printer. Add to that, SLA 3D printers uses a special type of "tree support" to support overhung features in the printed part. Again, this makes SLA 3D printers better for detailed objects. in a nutshell SLA = better for small details.
SLA Cons:
SLA 3D printers are relatively advanced printers so they are more expensive than FDM 3D printers. Also, they require a small work station that includes the printer, the washing comparments, the Post curing compartment, and special storage for resins. . Also, remember that the resins are chemcial substances that must be operated in a ventilated environment, and must be treated carefully to avoice spillage and resin contamidation. This makes resin 3D printing a bit messy and in for some applications not woth the hassle. SLA 3D printnig is not only messy, but it is reltivley exensive; the resin material used in SLA printers are at least 10 times more expensinve that filements used in FDM printers. Not only that, but in SLA 3D printing you cant control the inner structure and density of the 3D printed object. THis means that all objects must be 3D printed with 100% making them even more expenive compared to FDM prints.
2) SLS: Selective Laser sintering:
SLS 3D Printing Working Mechanism:
SLS 3D printers has a lot of similarties with SLA 3D printer; they both use a laser head to cure layers of material and create a 3D solid object. The main difference is that SLS 3D printers dont cure liquid resin material. Inseated, SLS printers use high energy laser to fuse powder metal to create solid metal objects. Here is how an SLS 3D printer works:
Whats going on in the diagram above is that the SLS 3D printer is using a laser head (1) to emit high energy beam. This high energy laser beam selectively hits regions of the raw powder (2) that is placed in the printer. The powder particles are a type of metal, and these particles fuses/weld to each other when hit with the high energy of the laser beam creating a solid layer of material. The build plate that is holding the powder gradually moves away from the laser head allowing it to fuse more layers of solid material to create a 3D solid object (3).
SLS 3D Printing Materials:
SLS printers 3D print metals, mainly nylon. There are some variations of the Nylons SLS printers print, but PA12 is the most common Nylon in most of SLS 3D printers. Mainly if you are looking for metal 3D printing, you are looking for SLS printers.
SLS Pros:
SLS printers 3D print with metals meaning you can expect the printed parts to be very strong, and to withstand high loads and temperatures. Its not only the strength that yumayez SLS prints, but also the quality; SLS 3D printers can produce highly detailed prints like the SLA printers with a nice extra: SLS 3D printing does not require any support structure! This makes SLS printers even better than SLA 3D printers when it comes to 3D printing details.
SLS Cons:
SLS 3D printers are even more dvanced than SLA 3D printers, and thus, more expensive. The material used with SLS 3D printers are also expensive making SLS 3D printed parts cost the most from all the 3 3D pritning technologies we discusses so far. The high price of SLS 3D printers and its materials is not the only inconveninece that comes with the printer; SLS 3D printing is also a messy operation (even messier than SLA 3D printing). SLS printers require powder managment, powder recycling device, print post processing station, and more! Add to that the health hazard of breating the powder dust in the air, or contimadting the powder with other dust particles. SLS 3D pritning is definetly considered a process that requires deligation and hight maintaince.