All Types of 3D Printers: 2018 Guide
3D printers have come a long way from when the first one was created in 1988. At first being quite slow and expensive to now having many types each with its own applications and advantages creating a boom of the demand for 3D printers in many industrial fields. It has now become so affordable that there are many commercial printers for as little as $300 and a high demand from individuals to get one for their own home.
Additive manufacturing is the process that 3D printers use where the printer lays the printing material layer by layer, one on top of the other until you have your final print unlike the more traditional manufacturing methods such as molding or reduction manufacturing. As of yet for the mass production of objects molding and reduction manufacturing are much quicker and cheaper. However, as 3D printers become cheaper and quicker, the manufacturing industry will shift to 3D printing as there are many advantages. For individual users such as for households or schools 3D printers give the chance to create whatever you imagine into something you can hold in your hands.
It begins with the creation of the object you want to print in a computer program such as CAD where you create a 3D model. The program then takes what you have created and fixes any errors which sometimes happens. Your model is then saved as a file that 3D printers can read most commonly being a STL file. Your model then has to be sliced into many layers sometimes by the same software or a special slicing software so that the printer knows how to print each layer. You then transfer this file to your printer via USB/SD card or wirelessly depending on what your printer has. The printer reads the file and begins to lay down the printing material layer by layer until the final print is done.
- 1)Fused Deposition Modeling (FDM) / Fused Filament Fabrication (FFF)
- 3) Digital Light Processing (DLP)
- 4)Polyjet 3D Printers
- 5) Laser Selective Melting (SLM)
- 6) Selective laser sintering (SLS)
- 7) Electronic Beam Melting (EBM)
- 8)Laminated object manufacturing (LOM)
- 9) Bio 3D Printers
- 10) Ultrasonic Additive Manufacturing (UAM)
1)Fused Deposition Modeling (FDM) / Fused Filament Fabrication (FFF)
Fused Deposition Modeling (FDM) is the most common type of 3D printers, being the cheapest and easiest to work with. How it works is that it melts the printing material ( generally some sort of plastic) into very thin layers and it lays one layer on top of the other until your print is finished. Once the print is done then the cooling starts and it’s when the layers stick together, if the heating process is uneven then it can cause a defect called warping which then deforms your print. To avoid deformation what people usually do is get a 3D printer with a heating bed allowing the print to cool evenly.
A common question when searching for this type of printer is what is a fused filament fabrication(FFF) printer, well the answer is it’s the exact same type of 3D printer but the phrase Fused Deposition Modeling(FDM) was trademarked so only certain companies have the legal right to use it as a result the other companies use (FFF) to describe their printer.
What are some types of (FDM/FFF) 3D printers?
There are a couple of options when it comes to FDM 3D printers. The most common sold is the already assembled ready to go type then there is the cheaper type, which are the DIY 3D printer kits. The kits come unassembled and it takes about 2-8 hours to assemble the printer. DIY kits have the advantage of being cheaper and easier to modify.
All FDM/FFF printers have either one or two extruders. The extruder is what heats the printing material and pushes it out to make thin strings which then becomes your print when stacked up.
One extruder means that you can only print in one color, which ever color the print material is. The advantage of having a dual extruder 3D printer is that you can have two color materials on the same print.
What type of materials do FDM printers use?
PLA(polylactic acid)- The most commonly used type of printing material sold in all colors and cool types of filament. PLA is environmentally friendly as it’s made from the starch of plants.
ABS(Acrylonitrile Butadiene Styrene)- This a really nice material to use as it melts very easily but then likes to contract while it cools which can cause defects. It tends to be strong if done right
HIP(High impact Polystyrene)- This material is less commonly used for FDM printers because it’s more expensive and very similar to ABS in strength and feel.
Wood PLA- An awesome property of Wood PLA is that it makes your print feel and look like wood but you give up some flexibility and strength compared to regular PLA or ABS.
Flexible (TPE) – Highly flexible/stretchable material that is very strong, it used to make wearable items and phone cases. It is quite challenging to work with TPE making it an uncommon material to use with FDM printers.
SLA 3D printing tech for an everyday user is quickly becoming desirable as it can produces strong, big prints quite fast. Although as of now both the printing material and the printers are quite expensive compared to FDM printers. It uses photopolymer resin as the building material, which comes in liquid form.
How does Stereolithography 3D layering work?
A designing computer program that separates the 3D model into sections, so that the printer knows how to print the model layer by layer, helps assist the printer . The process begins by first exposing UV light to the resin liquid that hardens, this creates the first layer of your print, and then the platform is lowered so that the next layer can be formed until your print is done.
How good are the prints created by stereolithography 3D printers?
Stereolithography 3D printing creates a highly accurate, durable and very strong affordable prints quite quickly. Many manufacturers use it to make prototypes for parts they want to test out and sometimes even the end product. It has now become a lot cheaper than before and now people are able to afford it as a hobby or even for small business.
What are the two most common types of SLA printers?
The most commonly used type of SLA 3D printer is the top-down approach. In this configuration the laser is located above the liquid and printing platform and the platform moves downwards deeper into the resin liquid as each layer is formed.
The second approach is the bottom-up approach where the laser is located below the liquid which shines through a transparent platform which is moving upwards out of the liquid as each layer forms. The advantage of this form of printing is that if your print has a cavity no liquid will get stuck in the cavity as the print is moved upwards.
3) Digital Light Processing (DLP)
DLP type of 3D printers are very similar to SLA printers in the sense that it shines a light source onto a photosensitive liquid which harden when light is shined upon it.
What is the main difference between DLP and SLA 3D printers?
The DLP 3D printers shine the laser first to a digital mirror device(DMD), and then it reflects the light onto the liquid forming each layer. The DMD is a device made of millions of micro mirrors and each mirror is like a pixel in each layer it’s printing.
Each mirror can tilt away from the light source or towards it. The mirror tilting towards the light source then reflects the light to the liquid and the mirrors tilted away do not reflect any light. This way you can reflect an image towards the liquid like a projector printing each layer much quicker.
Although this process is much quicker it also cost a lot more because the DMD component makes the printer more expensive.
Are DLP printers the best choice for making jewelry?
DLP printers are currently the top choice for most jewelers with which they can create the wax mold they need for customized jewelry. The reason this type of printer is the best choice is because it can create a really high resolution print with fine detail, which is the most important aspect of creating high quality jewelry, and this can be printed in a matter of hours.
DLP printers are now very commonly used by jewelers for making customized jewelry. With a 3D printer the process of customizing,making,molding and finally finishing the final product can be as quick as 24 hours. Before jewellers could take weeks with this process creating and perfecting the mold of customized jewelry by hand.
The process starts with creating the design of the customized piece on a designing program and then printing your final design. This print generally being many pieces of jewelry are made out of a wax like resin material. The wax 3D models are then dipped and covered by a layer of plaster and then taken out. Once the plaster is hard the mold is then cooked in an oven for several hours finishing the mold. The precious metal such as gold is heated,turned into a liquid and poured into the mold and once it’s cooled you have your customized jewelry.
What Is Photopolymer Resin Liquid?
Photopolymer Resin is the liquid material that SLA and DLP printers use to form prints by solidifying the resin with some kind of light source, generally UV light. Resin for printing is not so common and can cost around $75-$120 a liter.
4)Polyjet 3D Printers
The polyjet 3D printers patented by stratasys in the year 2000 is widely used in larger companies as it has a wide range of advantages and abilities other 3D printers don’t. Generally used for prototypes and sometimes even props in movies.
Polyjet creates very high resolution prints with the ability to customize the end result. There is a huge range of material available with polyjet printers that come in a gel like polymer before being cured by UV light.
How do Polyjet printers work?
Polyjet uses inkjet technology similar to an ink printer to create high quality prints. The jetting head of the printer moves on the X a Y axis releasing gel polymer creating a very thin layer of about 16 microns. The head is built with two UV lights in the side which cure and harden the layer almost immediately after it’s laid down. The platform where the print is being printed on moves on the Z axis (down) so that the next layer can be placed on top of the last until your print is finished.
What are the main advantages of Polyjet 3D printers?
This method of printing has the ability to mix two types of materials giving you the advantages of both materials in your print. With a huge variety of printing materials the user can customize the strength, flexibility, durability and composition of their print. This is why many larger companies use this type of printing as it has many applications in many different fields.
Another huge plus is the speed it can print at and how easy it is to use. You can basically click the print button after you have told it what to print and very quickly you will have your print.
5) Laser Selective Melting (SLM)
SLM printers generally use metal powder as the printing material, unlike the other types of printers that use liquid or solid printing materials. Although very expensive and a slow method of printing it allows you to have metals prints with high density making them very strong.
The military and aerospace have been known to use this form of 3D printer for their applications in building metal parts. It is quite costly so it’s not commonly found in households.
What is the process of SLM printing?
First a wiper( powder deposition mechanism) lays a very thin layer of metallic powder onto the building platform which is then evenly leveled, then a highly powered laser is aimed at some mirrors which then concentrate the light onto the metal powder. The powder metal is heated to 1000 degrees by the laser which causes the metal to liquify which is then rapidly cooled and solidified.
The excess powder is then wiped to the sides, which falls into powder bins which is then recycled for the next print. The printing platforms lowers downs and the process is repeated layer by layer until it’s finished.
6) Selective laser sintering (SLS)
SLS type of printers are very similar to SLM in that they use powder material which is then laid out into the platform, leveled out and heated by a laser. Although there is some significant differences in a molecular level.
What are the principal differences between SLS and SLM printers?
The main difference is that SLS printers use materials such plastics, glass and ceramics powders where the printing material is never fully melted but is heated enough to so that the printing material can stick to each other which is called sintering. SLM printers primarily use metallic printing powder that is fully melted to achieve the formation of the print.
7) Electronic Beam Melting (EBM)
EMB is built in a similar way with similar principles to SLM in that it heats a metallic powder like substance to create the print but the way it heats the print material is different giving it some advantages such as being able to create titanium prints by achieving higher melting temperatures.
How do EBM printers work?
The EBM printers also have a wiper which lays down a layer of metallic powder and also leveling it exactly like SLM printers at first.
Using 60,000 volts of electricity the printer heats up the filament at the top of the printer, electrons jump from the filament down through an anode which is surrounded by magnets. The magnets create a magnetic field to direct the electrons to exactly where they have to hit the powder.
After the electron beam hits the powder it heats it up kinetically from the electrons hitting the powder at an extremely fast speed. This whole process is done in a closed and very specific environment within the printer so that it can work effectively.
What are the main applications EBM printers are used for?
EBM printers are able to produce higher melting temperatures so it is mostly used to create titanium parts which are stronger and lighter. This is why aerospace and airplane creators find this printer very useful to print airplane or flying craft parts. Another area this is hugely used in is making titanium implants in the medical field.
8)Laminated object manufacturing (LOM)
The LOM printing system has huge potential when it comes to 3D printing because it uses cheap printing material which is most commonly paper, it is very quick, and it has the ability to fully color your print. Although still expensive they are becoming cheaper and more attractive to smaller companies and even for households.
What is the printing process of LOM printers?
The printer is built with two rollers in each side, one side is the carrier roller where thin sheets of paper or plastic come out and the other roller is the receiving roller that takes the waste. This rolling system is the same system that the newspaper printing machines use to move paper print and create newspapers.
On the top there is a CO2 laser which then outlines and cuts the first layer. The platform moves down then a adhesive depositing device puts adhesive(glue) on top of the first layer. A brand new sheet of paper is rolled on top of the first layer which is then outlined and cut by the laser to form the second layer. A heating roller rolls on top of the two layers activating the adhesive gluing both layers together. This whole process is then repeated until the print is done.
What are the advantages and disadvantages of LOM printing?
The advantages of LOM printing are that it uses a very common material which is paper to print. This makes it very easy to get the printing material and also very cheap to make prints. Because it mostly uses paper to print they have added a device to add color to the prints as paper is easier to color than other materials. Most of the other printers use heat to form a certain type of material and then let it cool, if this is done incorrectly deformation and imperfections ruining the print. With LOM printing you never have to worry about the heating and cooling process because it uses a much simpler system than that so it’s hard to ruin the prints.
The first disadvantage of using this 3D printing system are the limited print materials you can use with it as it has to be able to be flexible to roll from one side to the other. Also there is a lot of waste left after the paper is cut and rolled unlike other 3D printing systems. The biggest disadvantage might be that this system is limited in how complex the prints can be.
9) Bio 3D Printers
Biological printing is one of the newest forms of 3D printing which is being used to print out human organs for organ transplants. This is a huge advancement in the medical field and could save many lives. As of yet simpler human parts can be printed such as an ear or skin but in a couple years they will be able to print full organs.
How do Bio printers print organs?
A Similar idea to most 3D printers you first need the printing material which in this case is bio ink made of human cells. The printer has two injectors on the top, first one lays down a water based gelatin layer and the second injector injects the human cells into the gelatin and it does this layer by layer. After that nature takes over and it starts to properly build the organ.
10) Ultrasonic Additive Manufacturing (UAM)
UAM is one of the newest printing technologies yet being fully developed. It uses sound waves to create vibrations that then unifies one metal layer with another. This has quite a few advantages over the other printing methods which require the melting of the printing material which changes the state of the printing material.
The vibration made by the horn which is laid on top of the thin layers causes the molecular oxides to break up temporarily between the metal layers which then stabilizes making the two layers stick from the pressure and heat but never actually melting. This causes really strong bonding between layers making a stronger finish.