In the previous article we made a kind of introduction to the world of 3D printers. Now it's time to delve a little deeper into this technology, knowing more about the secrets that these teams hide, as well as the types of 3D printers that exist. Something vital when choosing the right one, since they all have their advantages and disadvantages, so there will always be one that is more in line with your needs.
Types of 3D printers according to printing technologies
The types of 3D printers are very numerous, and can be classified according to various criteria. Here are some of the most important:
main families
Just as conventional printers also have several families, 3D printers could be classified mainly into 3 groups:
- Red: it is not a common ink, but a powder compound such as cellulose or plaster. The printer will build the model from this conglomerate of dust.
Advantages | Disadvantages |
---|---|
Inexpensive method to produce in large volume. | Very fragile pieces that need to undergo hardening treatments. |
- Laser/LED (optics): is the technology used in 3D resin printers. They basically contain a liquid in a reservoir and are subjected to laser exposure to solidify the resin and UV curing to harden. That makes the resin (acrylic-based photopolymer) is transformed into a solid piece with the shape that is needed.
Advantages | Disadvantages |
---|---|
You can print very complex shapes. | They are expensive. |
Very high printing precision. | More intended for industrial or professional use. |
Excellent surface finish requiring little or no post-processing. | They can generate toxic vapors, so they are not very suitable for homes. |
- Injection: are those that mainly use filaments (usually thermoplastic) such as PLA, ABS, Tuvalu, nylon, etc. The idea behind this family is to create shapes by deposition of molten layers of these materials (they can be very varied). The result is a robust piece, although slower and with less precision than the laser.
Advantages | Disadvantages |
---|---|
affordable models. | They are slow. |
Recommended for hobbyists, home use, and education. | They form the model in layers, and depending on the thickness of the filament, the finish may be of poorer quality. |
Multitude of materials to choose from. | Some parts rely on supports that must be printed to hold the part. |
Robust results. | They need more post-processing. |
There are many makes and models to choose from. |
Once these families are known, in the following sections we will learn more about each of them and the technologies that may exist.
Resin and/or optical 3D printers
The resin and optical 3D printers They are one of the most sophisticated and with the best results in their finishes, but they are also usually much more expensive. In addition, they will also need additional machines such as washing and curing in some cases, since these functions are not integrated into the printer itself (or in cases where cleaning the parts in an MSLA is cumbersome).
- Washed: After printing the 3D part, a washing process is needed. But instead of brushing and spray cleaning the part, you can take the finished part off the build platform and use the washing machines. These will act as an automatic car wash, with a propeller that rotates magnetically inside and agitates the cleaning liquid (a tank full of isopropyl alcohol -IPA-) inside the hermetically sealed cabin.
- Healing: after cleaning, it is also necessary to cure the piece, that is, exposure to ultraviolet rays that alter the properties of the polymer and harden it. To do this, the curing station removes the part from the cleaning liquid where it was submerged, dries it while turning it to reach all sides. Once this is done, a UV LED bar will begin curing the piece, as if it were an oven.
SLA (Stereo Lithography)
This stereolithography technique it's a fairly old method that has been revamped for 3D printers. A photosensitive liquid resin is used that will harden in the places where the laser beam hits. This is how the layers are created until the finished piece is achieved.
Advantages | Disadvantages |
---|---|
Smooth surface finish. | High cost. |
Capable of printing complex patterns. | Less environmentally friendly. |
Best for small parts. | Needs curing process after printing. |
Fast | You cannot print large parts. |
Variety of materials to choose from. | These printers are not the most durable and robust. |
Compact and easy to transport. |
SLS (Selective Laser Sintering)
It is another process of selective laser sintering similar to DLP and SLA, but instead of a liquid a powder will be used. The laser beam will melt and adhere the dust particles layer by layer until the final model is formed. The advantages of this method is that you can use many different materials (nylon, metal,…) to create parts that are difficult to create using traditional methods such as molds or extrusion.
Advantages | Disadvantages |
---|---|
Batch printing can be done in an easy way. | Limited amount of materials. |
The printing price is relatively affordable. | It does not allow the recycling of the material. |
Does not need supports. | Potential health risks. |
Highly detailed pieces. | The pieces are brittle. |
Good for experimental use. | Post-processing is tricky. |
You can print larger parts. |
DLP (Digital Light Processing)
This technology of digital light processing is another type of 3D printing similar to SLA, and also uses light-hardened liquid photopolymers. However, the difference is in the light source, which in this case is a digital projection screen, focusing on the points where the resin needs to harden, speeding up the printing process compared to SLA.
Advantages | Disadvantages |
---|---|
High printing speed. | Unsafe consumables. |
Great precision. | Consumables have a high cost. |
It can be good for various application areas. | |
3D printer with a low cost. |
MSLA (Masked SLA)
It is based on SLA technology, and shares many of its features, but is a type of masked SLA technology. That is, it uses an LED array as a UV light source. In other words, it has an LCD screen through which light is emitted that matches the shape of a layer, exposing all the resin at once and achieving higher print speeds. That is, the screen is projecting slices or slices.
Advantages | Disadvantages |
---|---|
Smooth surface finish. | High cost. |
Capable of printing complex patterns. | Less environmentally friendly. |
Printing speed. | Needs curing process after printing. |
Variety of materials to choose from. | You cannot print large parts. |
Compact and easy to transport. | These printers are not the most durable and robust. |
DMLS (Direct Metal Laser Sintering) or DMLS (PolyJet Direct Metal Laser Sintering)
In this case, it generates objects in a similar way to SLS, but the difference is that the powder is not melted, but is heated by the laser to the point where can fuse at the molecular level. Due to the stresses, the pieces are usually somewhat brittle, although they can be subjected to a subsequent thermal process to make them more resistant. This technology is widely used in industry to manufacture metal or alloy parts.
Advantages | Disadvantages |
---|---|
Very useful industrially. | faces. |
They can be used for printing metal parts. | They are usually large. |
Does not need supports. | Parts can be brittle. |
Highly detailed pieces. | It needs a post-process that includes annealing to fuse the metals or other types of materials. |
You can print pieces of many different sizes. |
Extrusion or deposition (injection)
When we talk about the family of printers that use deposition techniques using material extruders, one can differentiate between the following technologies:
FDM (Fused Deposition Modelling)
These modeling techniques depositing molten material to compose the object layer by layer. When a filament is heated and melts, it passes through an extruder and the head moves in the XY coordinates indicated by the file with the printing model. For the other dimension use a Z offset for the successive layers.
Advantages | Disadvantages |
---|---|
Closed. | They are big machines for industry. |
Wide variety of materials to choose from. | They are not cheap. |
Good quality finishes. | They need more maintenance. |
Fused Filament Fabrication
Differences between FDM and FFF? Although sometimes used as a synonym, FDM is a term that refers to a technology developed by Stratasys in 1989. In contrast, the term FFF has similarities, but was coined by the creators of RepRap in 2005.
With the popularization of 3D printers and the FDM patent expiration in 2009, the way was paved for new low-cost printers with a very similar technology called FFF:
- FDM: large and closed machines for use in engineering and with high quality results.
- FFF: open printers, cheaper, and with poorer and more inconsistent results for applications in which parts with very specific properties are needed.
Advantages | Disadvantages |
---|---|
They are inexpensive. | Rough surface of the pieces. |
The filament can be reused. | Warping (deformation) is frequent. That is, a part of the object you are printing is curved upwards due to the temperature difference between layers. |
They are simple. | The nozzle tends to get clogged. |
There is a wide variety of materials to choose from. | They take a long time to print. |
They are compact and easy to transport. | Layer shift problems due to lack of adherence between layers. |
You can find them both finished and in kits to assemble. | Weakness. |
The bed or support needs frequent calibration. |
Other types of advanced 3D printers
Apart from the above types of 3D printers, or printing technologies, there are others that may not be popular for home use, but are are interesting for industry or research:
MJF (Multi Jet Fusion) or MJ (Material Jetting)
Another 3D printing technology that you can find is the MJF or simply MJ. As its name suggests, it is a process that uses the injection of materials. The types of 3D printers that have embraced this printing method are primarily intended for the jewelry industry, achieving high quality by injecting hundreds of tiny droplets of photopolymer and then going through a UV (ultraviolet) light curing (solidification) process. .
Advantages | Disadvantages |
---|---|
High printing speed. | It does not have ceramic materials commercially available at the moment. |
Suitable for business use. | Technology not too widespread. |
High degree of automation during the printing and post-processing process. |
SLM (Selective Laser Melting)
It is an advanced technology, with a very high-power laser source, and 3D printers of this type have quite high prices, so it is intended for professional use. In a way, they are similar to SLS optical technology, selectively fusing by laser. Very used in selectively melt metal powder and generate very robust pieces layer by layer, so you avoid certain subsequent treatments.
Advantages | Disadvantages |
---|---|
You can print metal parts with complex shapes. | Limited amount of materials. |
The result is a precise and robust piece. | They are expensive and large. |
Does not need supports. | Its energy consumption is high. |
Suitable for industrial use. |
EBM (Electron Beam Melting)
Technology electron beam fusion it is an additive manufacturing process very similar to SLM, and deeply rooted in the aerospace industry. It is also capable of producing very dense and robust models, but the difference is that instead of a laser, an electron beam is used to melt the metal powder. This technology for industrial use can lead to melting at temperatures of 1000ºC.
Advantages | Disadvantages |
---|---|
You can print metal parts with complex shapes. | Very limited amount of materials, as it can currently only be used for certain metals such as cobalt-chromium or titanium alloys. |
The result is a precise and robust piece. | They are expensive and large. |
Does not need supports. | Its energy consumption is high. |
Suitable for industrial use. | They need qualified personnel and protection measures for their use. |
BJ (Binder Jetting)
It is another of the existing types of 3D printers, with a technology used at an industrial level. In this case, it use a powder as a base for the manufacture of parts, with a binder to form layers. In other words, it uses powders of the material together with a kind of adhesive that will later be removed so that only the base material remains. These types of printers can use materials such as plaster, cement, metal particles, sand, and even polymers.
Advantages | Disadvantages |
---|---|
Wide variety of materials to manufacture the pieces. | They can be large in size. |
You can print large objects. | They are expensive. |
Does not need supports. | Not suitable for domestic use. |
Suitable for industrial use. | It may be necessary to adapt the model to each case. |
Concrete or 3DCP
It is a type of printing finds more and more interest for the construction sector. 3DCP stands for 3D Concrete Printing, that is, 3D printing of cement. A computer-aided process to create structures of cement by extrusion to form layers and thus build walls, houses, etc.
Advantages | Disadvantages |
---|---|
They can build structures quickly. | They can be large in size. |
They are of great interest to the construction sector. | They are expensive and complex. |
They could enable the construction of cheaper and more sustainable housing. | Each case will need to adapt the 3D printer specifically. |
An important development for the colonization of other planets. |
LOM (Laminated Object Manufacturing)
The LOM encompasses some types of 3D printers that are used for the rolling manufacturing. For this, fabrics, sheets of paper, sheets or metal plates, plastic, etc. are used, depositing sheet by sheet for the layers and using an adhesive to join them, in addition to using industrial cutting techniques to generate the shape, such as can be laser cutting.
Advantages | Disadvantages |
---|---|
They can build sturdy structures. | They are not compact 3D printers. |
Possibility of choosing between very diverse raw materials. | They are expensive and complex. |
They may have applications in the aeronautical sector or in the competition sector for certain composites. | They need qualified personnel. |
DOD (Drop on Demand)
Another technique of drop on demand uses two 'ink' jets, one depositing the building material for the object and the other a dissolvable material for the supports. In this way, it builds layer by layer, using additional tools to form the model, such as a fly-cutter that polishes the area under construction. In this way, it achieves a perfectly flat surface, which is why it is widely used in the industry where greater precision is needed, such as to manufacture moulds.
Advantages | Disadvantages |
---|---|
Perfect for industrial use. | They can be large in size. |
Great precision in finishes. | They are expensive and complex. |
They can print large objects. | They need qualified personnel. |
Does not need supports. | Somewhat limited materials. |
MME (Metal Material Extrusion)
This method is very similar to FFF or FDM, that is, it consists of the extrusion of a polymer. The difference is that this polymer has a high metal powder load. Therefore, when creating the shape, post-processing (debonding and sintering) can be done to create a solid metal part.
UAM (Ultrasonic Additive Manufacturing)
This other method uses metal sheets that are layer by layer and fused together by ultrasound to blend the surfaces and create a solid part.
bioprinting
Finally, among the types of 3D printers, one of the most advanced and interesting for medical use, among other applications in the industry, cannot be missing. Is about bioprinting technology, which can be based on some of the previous techniques, but with particularities. For example, there are cases in which they are based on layer deposition, bioink jets (bioink), laser-assisted bioprinting, pressure, microextrusion, SLA, direct cell extrusion, magnetic technologies, etc. Everything will depend on the use that you want to give it, since each one has its potential advantages and limitations.
3D bioprinting has three fundamental phases What are they:
- Pre-bioprinting: is the process of creating a model, such as 3D modeling using 3D printing software. But, in this case, more complex steps are needed to obtain said model, with tests such as biopsies, computed tomography, magnetic resonance imaging, etc. In this way you can obtain the model that will be sent to print.
- bioprinting: When the different necessary materials are used, such as liquid solutions with cells, matrices, nutrients, bio-inks, etc., and they are placed in the print cartridge so that the printer begins to create the tissue, organ or object.
- Post-bioprinting: it is the process prior to printing, as was the case with 3D printing, there are also various previous processes. They can be to generate a stable structure, tissue maturation, vasculation, etc. In many cases, bioreactors are needed for this.
Advantages | Disadvantages |
---|---|
Possibility of printing living fabrics. | Complexity. |
It could solve the problem of the shortage of organs for transplantation. | Cost of these advanced equipment. |
Eliminate the need for animal testing. | Need for pre-processing, in addition to post-processing. |
Speed and precision. | Still in experimental stages. |
Types of 3D printers according to materials
Another way to catalog 3D printers is by the type of material they can print on, although some of the domestic and industrial 3D printers accept a variety of materials for printing (as long as they have similar characteristics, such as melting point,…), just as a conventional printer can use different types of paper.
metal 3D printers
All metals are not well suited to different types of 3D printers. In fact, using some of the technologies seen above, only a few can be handled. The most common metal powders used in additive manufacturing are:
- Stainless steel (various types)
- Tool steel (with different carbon composition)
- Titanium alloys.
- Aluminum alloys.
- Nickel-based superalloys, such as Inconel (an austenitic Ni-Cr alloy).
- Cobalt-chrome alloys.
- Copper based alloys.
- Precious metals (gold, silver, platinum,…).
- Exotic metals (palladium, tantalum,…).
3D food printers
It is more and more common to find 3D printers to make food using additive manufacturing methods. In this case, some of the most common are:
- Functional components (prebiotics, probiotics, minerals, vitamins, fatty acids, phytochemicals and other antioxidants).
- Fiber.
- Fats
- Different types of carbohydrates, such as flour and sugar.
- Proteins (animal or vegetable) to form meat-like textures.
- Hydrogels, such as gelatin, and alginate.
- chocolates.
Plastic 3D printers
Of course, one of the most used materials for 3D printing, especially for home 3D printers, is the polymers:
- Plastics like PLA, ABS, PET, PC, etc.
- High-performance polymers such as PEEK, PEKK, ULTEM, etc.
- Textile-type synthetic polyamides such as nylon or nylon.
- Water soluble such as HIPS, PVA, BVOH, etc.
- Flexible like TPE or TPU, like those of silicone mobile phone cases.
- Polymerization-based resins.
Also, if you are going to use a 3D printer to print objects for use in food, such as cups, glasses, plates, cutlery, etc., you should know what the food safe plastics:
- PLA, PP, co-polyester, PET, PET-G, HIPS, nylon 6, ABS, ASA and PEI. If you will use them to wash in the dishwasher or withstand higher temperatures, discard nylon, PLA and PET, since they tend to deform at temperatures between 60-70ºC.
Biomaterials
As for the 3D bioprinting, you can also find a wide variety of products and materials:
- synthetic polymers.
- Poly-L-lactic acid.
- Biomolecules, such as DNA.
- Low viscosity bioinks with cells in suspension (specific cells or stem cells). With hyaluronic acid, collagen, etc.
- Metals for prosthetics.
- Proteins
- Composites.
- Gelatin agarose.
- photosensitive materials.
- Acrylics and epoxy resins.
- Polybutylene terephthalate (PBT)
- Polyglycolic Acid (PGA)
- Polyether Ether Ketone (PEEK)
- Polyurethane
- Polyvinyl alcohol (PVA)
- Polylactic-co-glycolic acid (PLGA)
- Chitosan
- Other pastes, hydrogels and liquids.
Composites and hybrids
There are also other hybrid compounds for 3D printers, although they tend to be more exotic and very diverse:
- PLA-based (70% PLA + 30% other material), such as wood, bamboo, wool, cork filaments, etc.
- Composites (carbon fiber, fiberglass, kevlar, etc.).
- Alumina (mixture of polymers and aluminum powders).
- Ceramics. Some examples are porcelain, terracotta, etc.
- Metal oxides: alumina, zircon, quartz, etc.
- Non-oxide based: silicon carbides, aluminum nitride, etc.
- Bioceramics: such as hydroxyapatite (HA), tricalcium phosphate (TCP), etc.
- Cement-based compounds, such as different types of mortar and concrete.
- Nanomaterials and smart materials.
- And many more innovative materials that are coming.
According to uses
Last but not least, various types of 3D printers could also be cataloged according to use what will be given:
Industrial 3D printers
The industrial 3D printers They are a very particular type of printer. They usually have advanced technologies, in addition to being considerably large in size, and priced at thousands of euros. They are designed for use in industry, to be manufactured quickly, precisely and in large quantities. And they can be used in sectors such as aeronautics, electronics and semiconductors, pharmaceuticals, vehicles, construction, aerospace, motorsport, etc.
The industrial 3d printer prices can oscillate from € 4000 to € 300.000 in some cases, depending on the size, brand, model, materials and features.
Large 3D printers
Although this type of large 3d printers could be included within the industrial ones, it is true that there are some models designed for use outside the industry, such as some printers capable of printing large parts for those makers that need it, for small companies, etc. I am referring to those models that are not as big and expensive as the industrial ones, like Anycubic Chiron, Snapmaker 3D, Tronxy X5SA, Tevo Tornado, Creality CR 10S, Dremer DigiLab 3D20, etc.
Cheap 3D printers
Many mounting kits 3D printers for home use, or some open source projects, such as Prusa, Lulzbot, Voron, SeeMeCNC, BigFDM, Creality Ender, Ultimaker, etc., as well as other brands that sell compact 3D printers, have brought 3D printing to many homes as well. What previously only a few companies could afford, now can be priced similar to conventional printers.
Generally, these printers are intended for private use, such as DIY enthusiasts or makers, or for some freelancers who need to create certain models on an occasional basis. But they are not designed to create large models, neither massively, nor quickly. And, for the most part, they are made with resin or plastic filament.
3d pencil
Finally, to complete this article, I did not want to leave myself behind 3D pencils. They are not one of the types of 3D printers as such, but they do have a common goal and can be very practical to create some simple models, for children, etc.
they have a very cheap price, and basically are tiny pen-shaped handheld 3D printers with which to make drawings with volume. They usually use plastic filaments such as PLA, ABS, etc., and their operation is very simple. They basically plug into an electrical outlet and heat up like soldering irons or hot glue guns. This is how they melt the plastic that will flow through the tip to create the drawing.
Learn more
- Best Resin 3D Printers
- 3D scanner
- 3D printer spare parts
- Filaments and resin for 3D printers
- Best Industrial 3D Printers
- Best 3D printers for home
- Best cheap 3D printers
- How to choose the best 3D printer
- All about STL and 3D printing formats
- 3D Printing Getting Started Guide