3D printing is a manufacturing technique that turns a digital model file into a physical object. A complete object is constructed by adding layers upon layers of material.
In this beginner’s guide, we provide you with all the information you need to get started with 3D printing.
Introduction to 3D printing
It was initially termed rapid prototyping until the 1980s, when 3D printing was developed. In comparison with traditional methods, it enabled companies to build prototypes faster and more accurately. Over the past three decades, its uses have become much more varied.
The technology is used by manufacturers, engineers, designers, educators, medics, and hobbyists alike.
What can you 3D print?
3D printing is no different – it exists to solve problems or improve our lives. Let’s first look at what 3D printing is used for before diving into all the technical details.
Prototypes
Despite its origins as rapid prototyping, 3D printing is still widely used for this purpose. A designer or engineer can print their digital design and review it within hours, thanks to 3D printing.
It is possible to prototype in several different ways using 3D printing. In later stages of product development, designers can create a realistic mockup to assess shape and form and how the product feels in hand.
The engineers can also use various materials to perform functional testing on their prototypes, such as checking heat or impact resistance or fitting the design of a new component.
Functional parts
The majority of plastic products are made through injection molding – a process where molten plastic gets injected into a metal mold, where it sets into the desired shape. While this process can take just a few seconds and can be repeated many times, making the initial mold takes more time and is only economically feasible once you have made enough parts.
Would it be possible to order a few hundred instead? Can they be delivered by Thursday? That’s where 3D printing comes in.
As 3D printers are getting more reliable and capable of printing with a wider range of materials, including flexible rubber-like materials and strong glass composites, short-run manufacturing has become a realistic option.
The production process is more controllable and flexible with 3D printers. When a shipment of a component is delayed or demand spikes for your product, parts can be 3D printed so that production schedules remain on track. This is useful for manufacturing businesses and helped keep medics safe when PPE and other supply chains were not available during the COVID-19 pandemic.
In manufacturing and packaging, replacement parts are common because downtime and problems can be very costly. It is now possible to print a replacement part within hours if you can no longer source a part or if it frequently fails and requires optimization.
Tools
3D printed tooling is technically a functional part, but it is now so prevalent that it can be considered a category of application. Tools, jigs, and fixtures can be created whenever necessary for the manufacturing process to be more straightforward and more repeatable, for first-time-right results.
Models to illustrate concepts
3D printing is useful not just for designing and manufacturing products but also for visualizing concepts in 3D.
Models are used for many purposes, including architectural models of new developments, medical models for explaining procedures to patients, and educational visualizations.
The added benefit of 3D printing in education is that students gain experience using the technology, develop STEAM skills such as 3D design, and understand material properties and manufacturing processes.
How does 3D printing work?
To create an object, layers of molten plastic are built up during the 3D printing process. Layers are printed repeatedly, one after another, and the object is built up as each layer sets.
To create a 3D print, a digital file must be used that tells the 3D printer where to print the material. G-code files are the most common format for this. In basic terms, this file contains ‘coordinates’ that drive the printer’s horizontal and vertical movement, also known as XYZ axes.
These layers can be printed at different thicknesses, known as layer heights. In a similar way to pixels of a screen, adding layers to a print will increase its “resolution.” You will get a better-looking result, but the print time will be longer.
3D printing vs. additive manufacturing?
Additive manufacturing is known as a result of this layering process.
It is common to see the same manufacturing process referred to by different terms. Additive manufacturing is the opposite of subtractive processes, in which materials are removed (or subtracted) from a larger block to create the final object, for instance, CNC machining.
FDM vs FFF 3D printing – explained
The FDM (fused deposition modeling) and FFF (fused filament fabrication) processes may confuse newcomers to 3D printing. As both terms refer to a specific type of 3D printer, they are essentially different names for the same thing.
Are there different types of 3D printers? Yes, indeed! There is really no reason to get confused – we’ll take a quick look at these next.
What are the different 3D printing technologies?
Due to the versatility of plastics, there are many ways to manufacture them. Let’s explore the different methods of 3D printing.
Among the most widely used technologies are FFF 3D printing, SLA (stereolithography), and SLS (selective laser sintering).
What is FFF 3D printing?
During FFF, a heated nozzle is used to extrude a string of material, sometimes called filament. A motion system moves the nozzle around a build area to deposit melted filament onto a build plate. Layer by layer, the build plate moves down by a fraction of a millimeter as the material cools and solidifies.
What is SLA 3D printing?
Raw material for SLA 3D printing is UV-curable resin. The resin gets poured inside a glass-bottomed container, into which a build platform is submerged. Using UV light, the resin is selectively hardened in the shape of the desired cross-section. Over time, the platform slowly rises out of the container to build up the print.
What is SLS 3D printing?
Powdered raw material is used in SLS 3D printing, usually a polymer. In a container, the powder sits, and a blade applies it thinly to the build area. The laser is used to fuse the tiny particles to form a horizontal layer. The container is moved a fraction of a millimeter to begin a new layer, and the blade is used to deposit raw material. To create the finished object, this process is repeated.
Other types of 3D printing
In addition to the items listed here, you may find the following:
DLP (direct light processing) is a resin-based process similar to SLA. Instead of using a laser to cure individual points of resin, DLP uses light to project an image of the entire layer onto the resin.
Binder jetting – A powder-based process that is similar to SLS, although the powder is fused by a binding agent rather than by a laser.
Material jetting – A way of creating 3D parts by depositing wax or plastic material and curing it with UV light, a variation on “2D” inkjet printing.
SLM (selective laser melting) – One of several similar variations of SLS technology for metal 3D printing.
