What is 3D Printing?
3D printing, also called additive manufacturing, is a process of making three dimensional solid objects from a digital file.
The creation of a 3D printed object is achieved using additive processes. In an additive process, an object is created by laying down successive layers of material until the object is created. Each of these layers can be seen as a thinly sliced cross-section of the object.
3D printing is the opposite of subtractive manufacturing which is cutting out / hollowing out a piece of metal or plastic with, for example, a milling machine. These additive techniques enable you to produce complex shapes using less material than traditional manufacturing methods.
Due to the ability to produce very complex shapes and structures with high precision and repeatability from a diverse range of materials, 3D printing is used for a broad range of applications in: aerospace, automotive, construction, fashion, food, jewelry, manufacturing, and medical sectors. There are numerous techniques to 3D print objects using a wide variety of different materials.
What steps are needed to create a 3D printed Object?
- First, a virtual 3D representation of the object is created using computer-aided design (CAD).
- Then, the model is ‘sliced’ into a series of horizontal layers to convert the design into instructions code that is readable for the 3D printer.
- When the files are “sliced”, the settings that the 3d printer needs to print properly is also applied. This data is then transferred to the printer.
- Once the printer has received the instructions code, the final object can then be produced one layer at a time, with each layer bonding and building onto the previous one. - After the object has been created, it must then be processed into the finished product. This may include removing supporting material, sanding, smoothing, and/or painting.
What are the Benefits of 3D Printing?
-
Faster
For small to medium runs of small objects, 3D printing is already faster than many methods of traditional manufacturing, simply because of the time it takes to create the tooling for injection molds and casts required for traditional manufacturing. Reduced turnaround time on design and production is a major advantage for manufacturers.
-
Renewable and efficient
The additive nature of 3D printing makes it intrinsically less wasteful than subtractive manufacturing technologies like milling or machining. This has a tremendous benefit of using less material, producing less waste, and lowering costs of the finished product. 3D printing can also make use of renewable materials like plastic made from soybeans and other biodegradable substances. Therefore, 3D printing can be cheaper for the consumer and better for the environment.
-
Lower costs
The molds and casts required for conventional manufacturing methods are not cheap, so small to medium production runs can be far more affordable with 3D printing. This also makes it possible to create inexpensive one time or small batch productions of items at an affordable cost. This is because no special changes are needed to produce a variety of items.
-
Versatile
3D printing machines can create almost any shape or design of item without the need for alterations for each item created. Conventional mold injecting, casting, or milling methods are not as versatile, or cannot change what is created without costly or time consuming alterations to the production equipment.
-
Customizable
3D printing enables parts and items to be customized and personalized without slowing down production or incurring significantly more cost.
What is Fused
Deposition Modeling?
(FDM 3D Printing)
Fused deposition modeling (FDM), also called Fused Filament Fabrication (FFF) is the most common and inexpensive 3D printing technology. A spool of plastic filament (like a spool of wire) is unrolled and heated to its melting point, then extruded through a nozzle onto a platform. Once on the platform, the molten material cools and solidifies. The object is produced by forming layers one on top of another until the item is complete.
.jpg)
What is PLA?
(Type of 3D Printing Filament)
Polylactic Acid, shortened to PLA, is the world’s most popular 3D printing material. It is a type of plastic that is plant based instead of petroleum based. It is often made from corn or soybeans, which is a renewable, natural resource.
It is very popular because it can be printed at a low temperature, and does not always require a heated print bed (although it still helps!). There are almost infinite combinations of colors or blends of PLA with different mechanical properties for any application you could possibly think of.
Advantages of PLA Filament
-
Easy to print with: Some filaments like ABS tend to warp a lot, PLA prints at a lower temperature and warps considerably less. As a result, PLA does not require a heated bed, making the 3D printer safer, though a heated bed still helps create better quality parts.
-
Biodegradable and environmentally friendly: PLA is made from a renewable resource, usually from corn or soybeans, and under the right conditions, will even biodegrade.
-
No harmful fumes when printing: Whereas some filaments can create smelly or harmful fumes, PLA is safe and odorless, as it is formed from plants rather than petroleum-based compounds.
Inexpensive: PLA is one of the most inexpensive filaments, and for the price, offers good surface finish and of strength of parts.
Disadvantages of PLA Filament
-
Brittle: PLA is not very good for prints which need to be malleable or twisted in any way. Some improved filaments like PLA+ can help with this issue.
-
Problems with oozing: PLA tends to have difficulty with oozing and stringing when it is heated. This results in more cleanup work to create a finished part.
-
Not ideal for durable parts: Since PLA softens at around 60-65C or 140-150F, PLA is not suitable for parts that need to be used outside, or in hot temperatures. Moreover, filaments like PETG and ABS have stronger mechanical properties, so are better for functional parts.
Types of PLA Filament
There are a wide variety of different PLA types.
Here are a few examples:
-
PLA+: Regular PLA is improved by blending it with other plastics. It is known for being less brittle (a major drawback of PLA) and absorbs less moisture, as well as offering better mechanical properties.
-
Wood-filled: PLA mixed with wood particles can make the parts look or feel like wood. Can also be stainable or paintable.
-
Metal-filled: Gives parts a realistic metallic look. Mixes include stainless steel blends, aluminum, copper, brass and bronze PLA filaments.
-
Carbon fiber infused: For very strong, lightweight parts.
-
Flexible PLA: Mixed with TPU or similar materials.
-
Aesthetically modified PLA: Including glow-in-the-dark PLA, transparent or translucent blends, silk-like PLA, glittery and sparkly PLA, fluorescent, and color-changing PLA based on factors such as heat or UV light.
-
Lightweight (LW-PLA): Designed so it foams up when it melts, spreading to a larger surface area to print lighter parts that require less filament to print. It’s more expensive, but allows for up to 65% lighter parts.
How to Get the Best Results When Using PLA Filament
-
Reduce oozing: Because of PLA’s fast flowing speed, oozing and stringing can occur, making prints look less polished. By optimizing your retraction settings you can mostly prevent this from happening,
-
Use a cooling fan: A cooling fan makes a huge difference in quality, and prevents the plastic from stringing and creating imperfections. Having your fan set to high helps layers to cool before the next layer prints, especially on miniatures.
-
Print slower on smaller models: Small parts take less time to print each layer, leaving them less time to cool. Running your printer slower for small parts ensures layers have enough time to cool, reducing any deforming.
-
Optimize extruder temperature: Different PLA blends can have a variety of optimum temperatures. For example, carbon fiber-filled or wood-filled filaments are going to have very different melting points. Check for the best temperature for your particular filament before printing, and if stringing is occurring then you may need to alter the temperature slightly.
-
Use the right build surface: A layer of glue stick, blue builder’s tape, or a special coated build plate may help printing with PLA. Other surfaces like PEI film or just printing directly onto a glass heated bed may also work.
