1. What is 3D Printing?
3D printing is a process where a physical object is created as a digital model and then printed using different types of filament materials.
It was in the 1990s when its potential was slowly being recognized by the manufacturing world. It is and has always been sort of a technological marvel on how it can directly produce solid products straight from digital images.
3D printers are categorized as Computer Numerical Controlled machines or CNC’s. However, contrary to the traditional way of subtractive manufacturing, which is still the normal way of producing solid shapes and parts, 3D printing is an additive manufacturing method of production. Instead of machine cutting or using a drill to cut parts out of a block, 3D printing adds material one layer after another to complete the part.
3D printers are viewed as less efficient than traditional manufacturing methods for mass production, because they can take hours to produce one piece. However, their strength is in producing single parts, prototypes, rare pieces, and complex objects. 3D printers are also relatively inexpensive to use and require much less space and equipment. All you need is the 3D model, printer, and materials. Traditional manufacturing requires molds, presses, CNC machines which require space, time and money. 3D printing truly opens the door to anyone wanting to manufacture at home.
2. What is the history of 3D Printing?
1984- Charles Hull invented stereolithography or SLA, which is the precursor of the more advanced 3D printers in use today. The concept of taking a direct digital model to product manufacturing was the beginning of 3D printing.
3D systems- Co-founded by Mr. Hull, this company pioneered the machine named Stereolithographic Apparatus. This machine paved the way for big technological advancements in 3D printing.
1990's- Possibilities of 3D printing was so big it expanded all the way to medical science. Doctors successfully transplanted a lab-grown organ using a 3D printed synthetic scaffold that was coated with cells from the patient's own body.
2008- Another milestone for 3D printing happened when a disabled person was able to walk using a 3D-printed prosthetic leg.
2009- MakerBot industries, an open-source platform, began selling DIY kits that allowed people to build their own desktop 3D printers. Eventually, more and more 3D printers were bought and sold.
Fast forward to April 2019- Israeli scientists succeeded in creating a human heart entirely out of human cells. It was as big as a rabbit's heart and did not function, but it was considered a big leap in the medical frontier of cardiovascular medicine. The world's first 3D printed human organ.
3. Applications of 3D Printing
In the world of 3D printing, almost anything that you can digitally conceptualize can be 3D printed. If you can design it, you can print it. Many industries are already benefiting from the developing 3D printing technology. As more and more industries see it working, they see how it can be adapted to their respective industry.
Medical
Surgeons can now produce 3D-printed models of their patient's internal organs and other body parts giving them actual models to study, to plan surgeries, and to practice surgeries to minimize doctor error. Little steps in the advancement of quality of life.
Aerospace
3D printing is now used to make precise and lightweight parts for aircraft and space applications.
Automotive
The auto industry uses 3D printing for design check and innovation and improvement of existing engines as well as replacement parts.
Architecture
3D printing in architecture is used for design review, structure verification, scale modeling, and several other uses that involve Computer-Assisted Design (CAD).
Education
It is the perfect tool for 3D geometry visuals. It is even used as an art medium in schools. 3D printers are finding their way into college universities for learning and printing.
Entertainment
3D printing is used to produce prototypes of toys, games, action figures, and other entertainment items that are made of plastic. You might see a prop produced with a 3D printer for a play or performance.
Military
It is also useful for some applications in the army for parts that are used in defense equipment.
Manufacturing Industry
3D printing is used for making models for products that are slated for mass production. 3D printing fast tracks product development, troubleshooting, and innovation.
4. Why is 3D Printing Alternatively Called Additive Manufacturing?
3D printing is additive in nature as it adds material a layer at a time to create an object. Traditional manufacturing is subtractive in nature, as it removes material from an existing block.
By adding a thin layer over and over again on top of each other is where the coining of the term additive came about.
It is important to note that despite its inherent disadvantages for mass production, 3D printing costs a lot less than your traditional subtractive manufacturing methods. Its real advantage is the ability to produce instant unique and rare objects that are needed now. Once you have the model designed digitally you can start producing immediately.
5. What hardware and materials are used for 3D printing?
3D printing material is called a filament. Filaments come in the form of metals, wood, and plastics. The most commonly used filament is a plastic called thermoplastic. The two most common thermoplastics are Polylactic Acid (PLA) and Acrylonitrile Butadiene Styrene (ABS).
PLA is recommended for beginners because of its biodegradable nature and non-toxic properties. It is plant-based, widely available, does not give off any fumes and doesn't warp like ABS.
On the other hand, ABS is preferred by intermediate users who would want more accuracy and durability of their finished product. Despite its synthetic properties, ABS contains deeper color and lasts almost forever. ABS is commonly used to build toys like Legos.
Both PLA and ABS are categorized as thermoplastics for the reason that they are molded by melting, and later shaped as designed when hardened and cooled.
Material is made into reels of filament, thin strands, that are fed into the printer and come out through a nozzle called an extruder, as melted plastic. The melted plastic is thinly layered to create the object. PLA and ABS are ideal for 3D printing because of their ability to maintain their properties of gloss, strength, and durability even when they are melted and cooled back to form.
6. What are the popular types of 3D printers?
Although 3D printers operate using slightly different methods, all 3D printers revolve around the same principle of additive manufacturing.
Depending on the printer, some print large scale, some small scale. Different printers use different materials. It is always important when buying a printer to understand its capabilities as all 3D printers are not created equal.
Currently, there are 4 primary types of 3D printers in use today.
Stereolithography (SLA)
Is the oldest known 3D printing method. It works from the top of the object down; whereas, most 3D printers work from the bottom up.
SLA utilizes a resin liquid, positioned at the bottom of the printer. A platform is lowered, and mirrors direct the laser or ultraviolet lights to harden or cure the resin of the first layer. The layer is attached to the platform and slowly as a layer is completed the platform raises to allow for the next layer to be formed.
SLA printers are fast and very precise. However, the resin itself is expensive and requires special storage containers. The resin is photocurable which makes it sensitive to light. Additionally, they are not as strong as cured plastics such as the ones created in FDM machines.
SLA printed objects have the tendency to be brittle which makes it perfect for prototyping but is not suitable for production. It is, however, capable of making better precise, complex, and delicate structures compared to most 3D printers.
Fused Deposition Modeling (FDM)
FDM is one of the most popular types of 3D printing because it is one of the simpler methods.
It works by melting plastic such as ABS or PLA and is extruded through a printer head. The process is similar to your regular inkjet printer; except, it is done in a much slower fashion since hot plastic instead of ink is being pushed out of the nozzle. As the plastic cools down the layers fuse into each other forming the solid object.
The FDM type is inexpensive to build and its output relies on the quality and precision movements of its extruder. FDM printers come in multiple extruder heads that can print different materials along with the help of chemicals that fuse them together as they cool down. They also come in different colors, expanding the capabilities.
A downside to FDM is related to the way it builds layer by layer on top of each other. The finished object may have a tendency to be weak along its horizontal connection lines. Regardless, this printer continues to be the most popular type because of its simplicity and practical applications.
Selective Laser Sintering (SLS)
Similar to SLA, Selective Laser Sintering also makes use of lasers to manufacture solid shapes. The difference between the two is that SLA uses liquid resin while SLS uses powdered material allowing it to build anything from plastics to glass, and even a few metals.
SLS machines are usually used in highly specialized industries as they require powerful lasers. They can also be very expensive to build or even to acquire.
This type is useful for complex and intricate builds with durability.
Laminated Object Manufacturing (LOM)
The LOM type uses a laser to cut through sheets of material which are then put on top of each other and glued together to form a solid object. This method is best in creating large prototype objects.
This process requires a lot of post-production work where waste needs to be dug out before you are able to get to the finished product.
This type of 3D printing is much cheaper since the raw materials are made out of reams of paper or plastic.
7. What are the steps to 3D Printing?
Choose Your Design
Decide on the object you would like to print. Design the object into a digital model using computer assisted design software (CAD). Or purchase a premade model that you can often find through an online company.
Save the CAD file as an STL file type
Convert the CAD file into a Standard Tessellation Language (STL) file type. This conversion is necessary since the slicer software understands the STL language.
Slice the STL file
Import your STL file into slicer software. This is an important step as it slices the file into thin layers which is what tells the printer how to print. The sliced file will be converted to g-code which is what the printer can read.
Prepare Printer
Place the printer on a level and stable surface and safely out of reach of children or pets.
Prepare the Build Plate/Bed
To make sure that your object stays still and steady, it will either need a heated bed or a taped bed. If not heated, apply the tape to the plate to make sure that your object remains immobile while the printing process is going on. It is best to use special adhesive made for 3D printing.
Prepare Extruder and Filament
Check the extruder for excess filament from the factory. Remove any excess filament by pressing the release lever. Once the extruder is empty, load new material for use. Adjust the screws on your bed plate on all four corners to make sure that they are all tight.
Double-check the bed adhesion and filament flow, as well as x-height to achieve the balance for accurate printing. Don't forget to set the value in your software so that the printer knows what the gap is between the nozzle and the build plate.
Heat Up Your Printer
Put in your choice of material, and turn on your printer. For beginners, it is recommended to use PLA or Polylactic Acid thermoplastic. Aside from it being plant-based, it is also easy to use. Once it is heated up, check for melted plastic that is coming out of the extruder.
Get your File Ready and Start Building
Send the g-code file to the printer and start printing. The process may take a few hours to a whole day depending on the design and volume of the object being printed.
This is where 3D convenience comes in when all you have to do is sit and wait for it to finish.
Post Processing
Once the printing is complete, make sure to carefully remove the object from the machine and avoid damaging any small part. Use a small soft brush to remove any dust or particulate that might still be present. If your design was good, chances are the finished product will be a perfect replica.
8. What is Rapid Prototyping? How Is It Related to 3D Printing?
Rapid Prototyping is the process of quickly producing an object in order to evaluate it for mass production. 3D printing allows this process to be done very quickly and less expensively than making a mold. This is one of the better uses and more common uses of 3D printing.
9. What tools do I need for 3D printing?
It is important to have on hand the correct tools to adjust your 3D printer. Anytime you have equipment certain adjustments or tests need to be made. The following tools will help you produce better prints.
Flush cutter - Is used to make clean cuts and trims on the filament before and after loading it into the extruder. Your objects will produce better if starting with a clean cut. You can also use the cutter for removing excess plastic on the finished product.
Screwdriver - Use this to adjust and level the bed
Index Card - Setting the bed level and adjusting the distance from the base to the extruder.
Calipers – Used to determine exact measurements when making models.
Clean Cloth and a brush - For cleaning the extruder.
Gloves - For hand protection and handling the hot extruder.
Dish detergent - For removing dirt and grime.
Alcohol - For cleaning the build surface.
Proper Storage of Filaments - Filaments tend to absorb water and must be kept dry to avoid spoilage resulting in defective products. When exposed to water filament will expand during printing and it creates steam and bubbles that sizzle and pop as it is being extruded. This results in a rough and uneven finish. Store the filament in a dry container which should be located in a cool dry place. For added protection, you can use a dehumidifier to keep the moisture low.
Hopefully you have learned a thing or two from this article to help get you started on your way to 3D printing or improve the 3D printing you are already involved in. 3D printing is here to stay, the more you know, the better you will be in adapting this new technology.
