3D Printing : The Next Big (Bad?) Thing
What if you could get that last thing you ordered on Amazon in a matter of hours and not days? What if you could have custom fit clothes that didn’t cost a fortune? What if someone didn’t have to die to provide someone else with a new organ. Well, 3D printing could be the answer to all of those questions.
What is three dimensional printing?
To understand what is 3D printing, you first need to understand what is manufacturing. Manufacturing is the process of transforming raw materials into a final product. There are also four types of manufacturing: subtracting, forming, casting, and adding. It sounds complicated, but it is actually quite simple. Subtracting would be something like taking a big block of stone and chipping away at it, taking pieces away from it to create a statue or something. Forming would be something like making a clay figurine by taking clay and forming and shaping into the figurine. Casting would be something like taking liquified metal and pouring into a pre-made mold to make a metal pot or pan. And lastly additive manufacturing. This actually brings us back to our question of what is 3D printing? Additive manufacturing, also known as 3D printing, is the process of building up multiple layers of a material to create a 3D object. These ‘materials’ can be anything from plastic to aluminum to sugar to human flesh. But how does 3D printing use these raw materials to create 3D objects?
There are actually many kinds of 3D printing
The world of 3D printing continues to expand and evolve which leads to many new kinds of 3D printing. Some kinds are more expensive, some are cheaper, some are more ubiquitous, some more scarce. I have separated the leading kinds of 3D printing into 3 basic categories: the original techniques, the ubiquitous techniques, and the higher quality techniques.
The Original Techniques
The first 3D printing method is goes by multiple names and is known as vat photopolymerization, stereolithography, or SLA. There are multiple ways to use this technique, but they all consist of using a large vat of liquid resin, a certain kind of polymer that can be cured into a solid. This method then uses some sort of curing device such as a laser, projector, or LED to harden the material one layer at a time. This is the first and therefore least advanced method of the three categories. This method is not the most precise of the 3 kinds of 3D printing. In order to use this method, the user needs to have access to a vat worth of resin and some form of high powered curing device. Therefore it is not as accessible as any other more ubiquitous techniques.
The Ubiquitous Techniques
The second category is the ubiquitous techniques. These are going to be the kinds of 3D printing that are seen most often and can be used by almost anyone. The main method in this category is known as material extrusion. Material extrusion is the process of feeding materials into the machine and piping it back out through a nozzle into the desired shapes layer by layer onto a printing bed or the base of machine. This can be done with almost any material, but some materials cannot be extruded as is. A material like sugar or concrete can be extruded out in a malleable “liquid-esque” state and dry out later on, but with materials such as metals and plastics, the machine would have to melt them down prior to extruding them. This is the most ubiquitous method out of all the methods because it can be done with relatively cheap materials and with relatively compact machinery. If you have seen a 3D printer in real life, it was most likely a material extrusion printer. But as great as this method may be, it won’t have the level of precision that an industrial, high end 3D printer might have, which brings us to the last of the 3 categories of 3D printing.
The Higher Quality Techniques
This is by far the most broad out of the 3 categories because there are so many different kinds of methods involved. Each of the methods may not be as common as the material extruder, but they all contributed to the advancement of different techniques in the field as a whole.
The first of the methods in this category that I am going to talk about is material jetting. This process is like that of a normal inkjet printer that squirts out ink onto a paper. However, in the case of material jetting, the liquid being squirted out can later be cured or formed to make a solid layer of material. This is going to be on the more expensive side and is less available to the general public, but it does have one huge benefit: multiple materials. Unlike the other previous forms of 3D printing, this technique can print an object in using multiple materials at once. Material jetting printers often have multiple nozzles so that different materials can be laid down at the same time opposed to other printers such as the material extruder that only has one nozzle, forcing you to manually switch out the materials when needed. Another thing that material jetting allows users to do is print in full color, as in individual layers of color to form a cohesive piece. This is really important because with other printing methods, you would have to change the material itself to print in a different color. However, this is not the only type of higher quality 3D printing.
The second method is called binder jetting. This is done by laying down very fine layers of dust of a material such as metal or sand. Then a layer of a bonding agent will be applied over the dust to bind and set the material. Since the layers are so fine, this will produce very intricate and detailed prints. But there’s more. This method, like material jetting, is much more precise than the other, more ubiquitous methods of 3D printing. However, jetting substances is not the only higher quality method to 3D print.
The third method is powder bed fusion or Direct Metal Laser Sintering (DMLS). It involves a powdered material like binder jetting and a fusion agent such as a laser, electron beam, or energy with an chemical agent. A thin layer of the powder is laid down and then passed over by the fusion agent to bind certain parts of the powder together to create the first layer. More powder is laid on top and the fusion agent goes over it again. This process repeats over and over again until the entire product is complete. The object is then removed from the bed of powder, is treated with a heating process to completely solidify it, and is then ready for use. If done with energy and a chemical agent (which only works for plastic), it too can also be done in full color using colored agents. This method is also currently being used to print parts that are used for building various machinery.
Another method of higher quality 3D printing is direct energy deposition. These kinds of processes only work for metal prints. It is a bit like welding in 3D. A thin metal filament is laid down onto the printing bed and the metal is melted with a fusing mechanism such as a laser or an electron beam. It repeats the process of laying and fusing to create multiple layers that will cool down and harden into a solid. These techniques are most similar to material extrusion, the ubiquitous techniques, except that these methods use metals instead of plastics and a secondary fusing element instead of a heating element with the extruder itself.
The last kind of 3D printing that I am going to mention is sheet lamination. This is one of the most fairly simple processes but has to be separated into two catagories. Sheet lamination can be done with two kinds of materials: paper and metals. If using paper, a long sheet of paper is laid onto the printing bed using a conveyor belt mechanism. Then, a shape is cut out into the shape of the first layer. This is followed by the application of an adhesive that bonds the print to the bed and the other layers. This adhesive can be colored to then create prints in full color. This process repeats over and over to build many thin layers to make delicate prints out of paper. However, if this method is done using metal, then the same process occurs with a thin sheet of metal instead of paper and a laser is used to cut the layers. This same laser and/or a secondary heating element is what then bonds the layers to the printing bed and to each other. Using metal with this method creates less delicate and more durable prints. It can be used to then make tools and parts instead of paper models. This method could also be considered a more ubiquitous method because of the in-home machinery, but it is not quite at a level that competes with material extrusion.
The techniques that I have mentioned, as many as there may be, are not the only ones that exist. There are a countless amount of methods for 3D printing, all of which come with their own sets of pros and cons. No one method is perfect and each has a specific purpose. But why learn about the different tools if you don’t learn how to use them. Each of the various methods of 3D printing have various useful applications.
There are many applications of 3D printing,
some are meant for the public consumption and some are not.
The Public Applications
One of the most used applications of 3D printing is manufacturing prototypes. Companies often print small models of what they are planning to build such as buildings, sculptures, expensive machinery, etc. These are things that would be expensive and laborious to build and if the structure is not right or a measurement was off, forcing them to start again, it would be a serious detriment to the company. That is why companies 3D print smaller models of the thing they are trying to build in a cheaper material like plastic so they can visualize their goals and catch any mistakes. However, 3D printing is also very popular for making parts that would go into the actually project too. Usually, companies will print parts that are very specific in material or measurement. If a project requires a certain type of screw of a certain material, then they would print the part themelves. This allows for parts to be the exact fit for the project and can manufacture everything in house.
The Private Applications
There are also quite a few applications of 3D printing that are either less ubiquitous or are not as prepared for public consumption. One application is 3D printing houses. There are multiple different companies that are working on 3D printing houses and many are successful. The houses can be printed in as short as 24 hours whereas a normal house of similar size would take 2 months minimum. Moreover, the houses typically run cheaper than traditionally built houses. A few houses in California went on market and a 3 bed, 2 bath, and a pool went for $595,000. The average home in that area was reported to be around $825,700. Overall, these houses are much more affordable and can be built much faster than any other houses.
Another application of 3D printing is printing human body parts. 3D Bioprinting is one of the biggest advancements in the world of 3D printing. Many transplant and graft processes were unsuccessful due to the patients’ body not accepting the part. However, with 3D bioprinting, various parts can be printing using the patients’ own cells. As of now, 3D bioprinting works for skin grafts, ears, corneas, bones, and a few other things, but in a recent breakthrough, doctors are finding ways to print lungs and other various organs. With this, there should be almost no need for organ donor waitlists and patients would have a higher acceptance rate to transplants, making transplants much more effective.
There are various other applications for 3D printing in the works and hopefully can bring positive innovation to our world with less material waste and harmful output. However, is 3D printing actually doing more harm than good?
What are the disadvantages of 3D printing?
Are there even disadvantages of 3D printing? Well, yes. There are no disadvantages to the manufacturing itself. 3D printing reduces material waste and production time. It also reduces vehicle emissions in part transportation. However, for each of step of the manufacturing process, there are people making them happen. There are jobs there. Printing materials in-house eliminates the need for transportation personnel and some manufacturing warehouses. 3D printing houses eliminates the need for full construction teams which, depending on the project, can involves thousands of people. 3D printing can eliminate many people’s jobs. Also, there are many dangerous applications of 3D printing. 3D printers have the capability to print fully functioning guns out of almost any material. This makes these guns undetectable by any detectors because even certain types of plastics are strong enough to be made into these guns. As great as 3D printing is, it is also taking people’s jobs and could potentially kill many more people than it could save. So we have to decide, what are we trying to achieve? And at what cost?
In the end,
countless arguments can be made for and against the pros and cons of 3D printing. However, our world is advancing technologically very quickly, maybe too quickly. This world might not actually be ready for the rapid pace at which we are discovering new technologies. You should be able to decide for yourself where you stand and with this knowledge of this technology, you can. So, when looking into the world’s ‘next big thing,’ try to consider this: what are we willing to risk for innovation?
Thanks for taking the time to read my article. I hope you enjoyed it!
I am a 15 year old in high school with a passion for brain computer interfaces. In the future, I hope to write more about my adventures learning about this emerging technology.
Make sure to reach out to me with any comment, questions, or concerns at caitlinkim2024@gmail.com.
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Have a great day! :)
