What is Additive Manufacturing?
The term additive manufacturing aptly names the process it describes. It involves building (manufacturing) an object by adding layers of an additive, such as plastic or metal.
The manufacturing device gets its instructions on what layers to add from a downloaded model of a computer-animated design, separating this more technologically-advanced process from other forms of an assembly line or manual manufacturing.
Tools and Technology Required for Additive Manufacturing
Additive manufacturing has three basic requirements:
- A computer equipped with 3D modeling software: Some of the most prominent names in 3D modeling software include TinkerCAD, AutoDesk Fusion 360, Ultimaker Cura, and AutoDesk AutoCAD.
- Machine equipment: This is more commonly a 3D printer.
- Layering material, sometimes referred to as “filament” for certain design processes: This material can be anything used to build, such as plastic, metal, minerals, concrete, etc.
Process for Additive Manufacturing
Additive manufacturing reproduces objects on a small scale and creates specialized items that would be inefficient for large corporations.
Whether you are using additive manufacturing to produce simple, everyday items or are a professional looking to create a highly specific part on which precision is critical, additive manufacturing will require several distinct steps, with the details at each juncture tailored to the accuracy needed in your final object:
- Image creation: This involves making a sketch by hand, creating an illustration on computer software, or taking a series of photographs of the item you want to build. Be sure to capture all angles of the object you aim to manufacture.
- Image editing: It is necessary to pare the image down and remove any noise that is not relevant to the print, likely in a jpg file. If you are using a tool such as Adobe Photoshop, it will also be important to extrude a 3D image from a 2D file.
- 3D modeling: Move the computerized image from the photo editing suite to the 3D modeling software for further editing. Using advanced features in the 3D software, you will be able to view your object from all angles and add digital layers to perfect the final model.
- File extraction: After the model is the way you want it, it is necessary to download it as an STL file; this will give the printer instructions on how to add layers of material when creating the object.
- Manufacture: Once the file has been extracted and the print is approved, it is time to let the machine do its work. It will add material along all three axes (X, Y, and Z) until the object has been completed. The time from initiating manufacture to final cooling can take several minutes for small, simple items to many hours for more complex, specialized prints.
How is 3D Printing Different from Additive Manufacturing?
There really is no difference between 3D printing and additive manufacturing. They are the same thing, with the same tools, technology, and processes used for creating objects, regardless of the name applied. (In fact, Wikipedia only has one page created for 3D printing and additive manufacturing, listing them as alternate names for the same technology.)
However, some will argue that 3D printing is a subsection in the larger field of additive manufacturing, thus creating a distinction between them.
MachineMetrics argues that while 3D printing simply involves the printing of an object from a computer file, additive manufacturing is a much more holistic and complex process. Taken from Tangible Solutions, a leading manufacturer of medical implants, MachineMetrics claims that additive manufacturing involves:
- Designing structural supports that complement the manufactured object
- Developing creative ways to remove intricate items from the build plate
- Undertaking rigorous postprocessing to ensure an ideal finish
- Meticulously checking on the quality of the manufacturing process and the object produced
Proponents of differentiating the two names make their argument based on how sophisticated a process is. For example, they may argue that creating a car’s air conditioning control knob from a computer file is 3D printing while connecting all parts and building an entire vehicle from 3D prints is additive manufacturing.
Why Are There Two Different Terms?
As “additive manufacturing” and “3D printing” are two interchangeable terms, there is really no way to tell why one person may refer to additive manufacturing and another to 3D printing. Just understand that they are talking about the same process.
With that said, the two terms may be used in different situations to take advantage of certain marketing efficiencies. For example, the term “mechanic” and “certified automotive technician” are both used to describe someone who fixes cars. However, there may be times when one name may appear more appropriate (or appealing) than the other.
In general, additive manufacturing will be the preferred term when an air of professionalism is desired. The following are some situations in which you may be more likely to see additive manufacturing than 3D printing:
- When producing highly specialized items, such as in the medical implants example mentioned above
- When the objects produced are being sold on a commercial scale. The word “manufacturing” evokes a sense of industrialism that can lend credence to commercial enterprises
- When the process is being described in an academic paper or peer-reviewed journal (although such publications will usually acknowledge both terms)
On the other hand, 3D printing is used to evoke familiarity and make the manufacturing process seem accessible to everyone. In fact, the term “3D printing” is in itself a form of slang, with “3D” being the universally accepted jargon for “three-dimensional.”
Therefore, “3D printing” is more likely to be used when the manufacturing process is sought to be made fun and exciting. The following situations will likely see 3D printing used instead of additive manufacturing:
- When objects are produced at home or on a recreational basis
- When included as part of a middle school or high school engineering class
- When being used to describe the manufacturing process to unfamiliar parties, as the average person is likely more familiar with “3D printing” than “additive manufacturing.”
Differences in Manufacturing Processes
While the process of additive manufacturing and/or 3D printing involves the general series of steps listed earlier in the article, there are distinct processes and technologies used by the machines/printers during the fabrication of the object.
Although several nuanced manufacturing techniques are used, there are three overarching processes that machines follow when making their objects:
The type of printing technology used may influence whether the process is called additive manufacturing or 3D printing.
Fused deposition modeling (FDM) is the most common type of additive manufacturing/3D printing used. Thanks to its relative simplicity and affordability (many FDM printers can be purchased for around $200), this type of printing machine is common among hobbyists and recreational users.
FDM printers use thermoplastic filaments as building materials. This filament is melted and run through a nozzle, which uses instructions given by the STL file to deposit the melted filament at various points along the build plate. Moving along the three axes, the nozzle will continue to layer the filament until the object is complete.
Due to FDM printers’ prevalence for standard builds, this process will usually be referred to as “3D printing.”
Although complex manufacturers may use an FDM printer for creating objects, the following issues common with the FDM process are undesirable for those creators who prefer the term “additive manufacturing”:
- Build plate adhesion: As advanced additive manufacturing looks for ways to extract completed objects from the build plate cleanly, the FDM process can create some challenges. A wide base layer is required to prevent the item from slipping during layering; this can necessitate the use of rafts, brims, and supports, which—when combined with the wider base—can cause the object to stick to the base plate after cooling. This can lead to chipping and increased efforts to ensure the item is smooth, level, and/or symmetrical after extraction.
- Supported parts: As all layers of this build process must be connected to the base plate and initial layer, it is impossible to make a print containing multiple pieces; this becomes an issue for interlocking parts that require separate male and female components.
- Overhangs: Using FDM makes it nearly impossible to create objects with overhangs, as any unsupported part of the print may droop before cooling, which will throw off the entire result. Therefore, any intricate designs that require extending arms or overhangs will be difficult to make using this process.
These issues shed further light on why it is more common to hear the term “3D printing” than “additive manufacturing” when discussing FDM technology machines.
Stereolithography (SLA) uses a basin of resin to create a mold and a laser to solidify the finished object. This process is inverted from FDM builds. Instead of building up from a base plate, the item is essentially created upside down, using a build plate dipped into the resin bath below.
Although the object may not be as sturdy as those created from FDM builds, this manufacturing process yields a much higher resolution in the finished product; this tends to make SLA printers better than FDM machines for intricate designs and complex projects. SLA printers also tend to be significantly more expensive than FDM machines.
Due to the combination of these factors, it is likely that the term “additive manufacturing” will be used in conjunction with SLA printers.
Selective laser sintering (SLS) uses a bed of powdered plastic to form a mold of an object, with a laser solidifying and finishing the final product. This process is extremely similar to SLA manufacturing, with the only real difference being a liquid versus solid material basin.
SLS is another great option for making intricate builds, as the powdered plastic beds make it possible to create complex joints and interlocking parts. SLS manufacturing is the most expensive of all the printing processes.
Thus, SLS printers are likely to be used by creators who prefer the term “additive manufacturing.”
Differences in Common Modeling Software
Just as the machine used for the printing process may influence whether the build is referred to as “3D printing” or “additive manufacturing,” so too may the modeling software. As different modeling software comes with unique features and varying price points, certain options will appeal differently to casual and professional consumers.
The following breakdown looks into which common modeling software will likely be used in conjunction with “3D printing” and “additive manufacturing.”
AutoDesk Fusion 360
AutoDesk Fusion 360 is arguably the premier 3D modeling software on the market. It offers an enhanced array of features and modeling capabilities that makes it a preferred choice for engineers, machinists, and designers.
This software has many key features that make it an ideal choice for fabricating highly efficient mechanical parts, including:
- A History Tree that allows for fast and accurate editing of parts
- A collaboration platform to work with other designers on the same project
- Leverage simulation to allow you to check the design’s quality from its very earliest stages
These, along with a host of other features, make AutoDesk Fusion 360 one of the most expensive 3D modeling software options on the market, with a price tag as high as $60 per month. While this price tag will likely drive away many recreational 3D printers, it can be considered the cost of doing business for engineering firms. Therefore, AutoDesk Fusion 360 will likely be referred to as a modeling software for “additive manufacturing.”
Ultimaker Cura is open-source software that can be integrated with 3D printers. It is a strong choice for new users, as it has a recommendation mode that can help guide them through the modeling process.
It offers a surprising number of features for free software, including:
- Easy to navigate, with new users requiring little training to access all its features
- Widespread compatibility with various 3D printers and file types
- Customization mode for a higher level of control to meet specific requirements
However, as free software, it does have some limitations, such as a long wait time to complete 3D prints and a limited ability to view a model from all angles when in 3D mode.
Due to these limitations and the convenience it affords beginning designers, Ultimaker Cura will likely be referred to as a modeling software for “3D printing.”
AutoDesk AutoCAD is another outstanding 3D modeling software intended for professional use. It allows for a highly scientific approach to the design process, with users able to import data from PDF files, add annotations to drawings, and extract objects to data tables; this can allow the user to visualize data better and make use of real-time analytics.
Best utilized by professional 3D manufacturers with extensive experience in algorithmically processing 3D models, a few of the many features that this advanced suite provides include:
- A dual web and smartphone application
- Preloaded designs and plugins for common products, such as doors and windows
- The latest version of the DWG file format that allows for quick conversion and compatibility of images imported from various formats
With all these features comes an enormous price tag, with a subscription costing $1,449 per year. This high price, along with the advanced features it provides, likely takes AutoCAD out of the consideration set for beginning 3D printers and makes it a modeling software best suited for professionals who prefer the term “additive manufacturing.”
TinkerCAD is a web-based software that simplifies the 3D modeling experience. It has a straightforward interface that uses various simple shapes and shapes groupings to build more complex models digitally.
Some of the key features provided by this free software include:
- Cloud storage to save designs to be completed later
- Detailed tutorials to help users get the most out of the software’s capabilities
- Laser cutting to splice and pare down designs
While TinkerCAD does have features that are desirable for professional designers, its zero-cost price tag and intuitive interface make it ideal for novice users who are more likely to use the term “3D printing.”
Differences in Printing Projects
As the terms “additive manufacturing” and “3D printing” will likely be used differently based on the type of printing technology and modeling software used, it stands to reason that the objects created for each term will differ, as well.
As “additive manufacturing” tends to refer to the more intricate process that utilizes the most advanced printers and modeling software, you can expect to see the following types of objects created:
- Dental implants
- Parts for engines and robotic motors
While this is just a few of the possibilities, it does show that additive manufacturing can be used to solve some important engineering problems.
On the other hand, the term “3D printing” will likely be used when creating everyday objects that may not have as much scientific import hanging on their manufacture. Some examples include:
- Cell phone cases
- Coverings and parts for DIY repairs and craft projects
Additive Manufacturing vs. 3D Printing: A Historical Perspective
Some people argue that while additive manufacturing and 3D printing have generally referred to the same process throughout the years, the two terms’ most modern interpretation reveals a noticeable distinction between the two.
While both terms originally referred to the process of creating a 3D print from a digital model, additive manufacturing has mushroomed over the years to envelop the improvements in engineering, modeling software, and material filaments used to create objects through this process.
As advanced specialization will continue to be required as technology improves, the chasm between additive manufacturing and 3D printing will only continue to widen in the minds of some.
On the other side of the token, some within the industry believe that a distinction between the two terms will only become more nebulous as we move into the future. This party believes that 3D printing has historically referred to a more rudimentary form of object creation, while additive manufacturing was reserved for professionals who had access to the best technology.
As open-source software continues to improve and at-home printers become increasingly sophisticated, it can also be argued that what has traditionally been referred to as “3D printing” is no different than additive manufacturing itself.
Additive Manufacturing vs. 3D Printing: An Alternate Comparison
If you are still having trouble making sense of how these two seemingly different terms refer to the same process, it is worthwhile to create an analogous comparison to the situation. A great place to start is by drawing a comparison between “publishing” and “printing.”
Both terms can refer to the process of transcribing words to a medium that can be shared with other people. Therefore, it can be argued that the two terms are interchangeable. However, there is also an argument to be made that they are distinct.
- “Printing” can be viewed as the isolated act of transcribing words from one source to another, which is part of the publishing process, but not publishing in and of itself.
- “Publishing” is more likely to be seen as a much more holistic process that goes above and beyond the simple transcription of words to include such factors as editing, designing covers and images, marketing, distribution, etc.
In this case, “publishing” would be analogous to “additive manufacturing,” and “printing” would be equivalent to “3D printing.”
Interestingly, the debate between these seemingly different terms has intensified as technology has reached consumers’ hands. At one time, you had to hire an agent, find an editor, and get your work accepted by a publishing house to get a book published. Now that you can upload a file to open-source software and have a book printed on-demand, does that make you any less of an author?
Similarly, at one time, you had to work in large plants in very specific, industrial locations to be considered a manufacturing professional. Now that you can make custom objects from the comfort of your own home, does that make you any less of a manufacturer?
Based on their definitions, examples, scenarios, and analogies, “additive manufacturing” and “3D printing” are two essentially different terms for the same process. For the most part, additive manufacturing and 3D printing are two terms that describe the process of creating a multi-dimensional object from a digital computer design.
However, despite this conclusion, it is still possible to find distinguishing characteristics between additive manufacturing and 3D printing.
Additive manufacturing generally refers to a more holistic process that includes planning, designing, printing, finishing, and testing products. The term is preferred by professionals and will likely be used when the manufactured products are sold for commercial gain. It is highly likely that you will see “additive manufacturing” used in the following situations:
- Any time the words “engineering” or “architectural” are used in conjunction with the manufacturing process (academic classes being the exception)
- The entire process for building an object, from initial planning to post-fabrication inspections, is being described
- Advanced, typically for-pay software is used to create 3D models
- The parts being made are specialized and require a high level of precision
Conversely, 3D printing can be considered the isolated act of taking a computer-animated design and turning it into a tangible object through a machine printing process. It is often thought of as less comprehensive than additive manufacturing. 3D printing is the preferred term for hobbyists and beginners, as “3D printing” carries a more fun and accessible connotation than “additive manufacturing.
You are likely to see “3D printing” used in the following situations:
- The printing is being done on an at-home, casual, or recreational scale
- As part of a middle school or high school class
- When describing the process to laypeople
- When shedding the more domineering “additive manufacturing” in a more fun or accessible light
- The specific step of building the object from a digital model is being discussed
Whichever term you choose to use, understand that both essentially describe the same process, with the preference largely laying with how the creator wants to be perceived.