How does 3d printing

3D Printing: What It Is, How It Works and Examples

3D printers might seem like they're right out of a science fiction movie, but they're proving to be useful in a variety of industries. | Image: Shutterstock

How Do 3D Printers Work?

3D printing is part of the additive manufacturing family and uses similar methods to a traditional inkjet printer — albeit in 3D. Additive manufacturing describes the process of creating something in layers, adding material continuously until the final design is complete. This term most often refers to molding and 3D printing.

It takes a combination of top-of-the-line software, powder-like materials and precision tools to create a three-dimensional object from scratch. Below are a few of the main steps 3D printers take to bring ideas to life.

How Does a 3D Printer Work?

3D printers are related to additive manufacturing. 3D printers use computer-aided design to understand a design. When a design is ready, a material that can be dispensed through a hot nozzle or precision tool is printed layer by layer to create a three-dimensional object from scratch.

3D Modeling Software

The first step of any 3D printing process is 3D modeling. To maximize precision — and because 3D printers can’t magically guess what you want to print — all objects have to be designed in a 3D modeling software. Some designs are too intricate and detailed for traditional manufacturing methods. That’s where CAD software comes in.

Modeling allows printers to customize their product down to the tiniest detail. The 3D modeling software’s ability to allow for precision designs is why 3D printing is being hailed as a true game changer in many industries. This modeling software is especially important to an industry, like dentistry, where labs are using 3D software to design teeth aligners that precisely fit to the individual. It’s also vital to the space industry, where they use the software to design some of the most intricate parts of a rocketship.

3D PRINTERS USE MODELING AND SLICING SOFTWARE TO GUIDE THE PRINTER IN CREATING EACH OBJECT. Video: Digital Trends

Slicing the Model

Once a model is created, it’s time to “slice” it. Since 3D printers cannot conceptualize the concept of three dimensions, like humans, engineers need to slice the model into layers in order for the printer to create the final product.

Slicing software takes scans of each layer of a model and will tell the printer how to move in order to recreate that layer. Slicers also tell 3D printers where to “fill” a model. This fill gives a 3D printed object internal lattices and columns that help shape and strengthen the object. Once the model is sliced, it’s sent off to the 3D printer for the actual printing process.

The 3D Printing Process

When the modeling and slicing of a 3D object is completed, it’s time for the 3D printer to finally take over. The printer acts generally the same as a traditional inkjet printer in the direct 3D printing process, where a nozzle moves back and forth while dispensing a wax or plastic-like polymer layer-by-layer, waiting for that layer to dry, then adding the next level. It essentially adds hundreds or thousands of 2D prints on top of one another to make a three-dimensional object.

3D Printing Materials

There are a variety of different materials that a printer uses in order to recreate an object to the best of its abilities. Here are some examples:

Acrylonitrile Butadiene Styrene (ABS)

Plastic material that is easy to shape and tough to break. The same material that LEGOs are made out of.

Carbon Fiber Filaments

Carbon fiber is used to create objects that need to be strong, but also extremely lightweight.

Conductive Filaments

These printable materials are still in the experimental stage and can be used for printing electric circuits without the need for wires. This is a useful material for wearable technology.

Flexible Filaments

Flexible filaments produce prints that are bendable, yet tough. These materials can be used to print anything from wristwatches to phone covers.

Metal Filament

Metal filaments are made of finely ground metals and polymer glue. They can come in steel, brass, bronze and copper in order to get the true look and feel of a metal object.

Wood Filament

These filaments contain finely ground wood powder mixed with polymer glue. These are obviously used to print wooden-looking objects and can look like a lighter or darker wood depending on the temperature of the printer.

The 3D printing process takes anywhere from a few hours for really simple prints, like a box or a ball, to days or weeks for much larger detailed projects, like a full-sized home.

How Much Do 3D Printers Cost?

The cost of 3D printers vary based on the size, specialty and use. The cheapest 3D printers, for entry level hobbyists, typically range from $100 to $500. More advanced models can range between $300 and $5,000. Industrial 3D printers can cost up to $100,000.

3D Printing Processes and Techniques

here are also different types of 3D printers depending on the size, detail and scope of a project. Each different type of printer will vary slightly on how an object gets printed.

Fused Deposition Modeling (FDM)

FDM is probably the most widely used form of 3D printing. It’s incredibly useful for manufacturing prototypes and models with plastic.

Stereolithography (SLA) Technology

SLA is a fast prototyping printing type that is best suited for printing in intricate detail. The printer uses an ultraviolet laser to craft the objects within hours.

Digital Light Processing (DLP)

DLP is one of the oldest forms of 3D printing. DLP uses lamps to produce prints at higher speeds than SLA printing because the layers dry in seconds.

Continuous Liquid Interface Production (CLIP)

CLIP is amongst the faster processes that use Vat Photopolymerisation. The CLIP process utilizes Digital Light Synthesis technology to project a sequence of UV images across a cross-section of a 3D printed part, resulting in a precisely controlled curing process. The part is then baked in a thermal bath or oven, causing several chemical reactions that allow the part to harden.

Material Jetting

Material Jetting applies droplets of material through a small diameter nozzle layer-by-layer to build a platform, which becomes hardened by UV light.

Binder Jetting

Binder Jetting utilizes a powder base material layered evenly along with a liquid binder, which is applied through jet nozzles to act as an adhesive for the powder particles.

Fused Deposition Modeling (FDM)

FDM, also known as Fused Filament Fabrication (FFF), works by unwinding a plastic filament from a spool and flowing through a heated nozzle in horizontal and vertical directions, forming the object immediately as the melted material hardens.

Selective Laser Sintering (SLS)

A form of Powder Bed Fusion, SLS fuses small particles of powder together by use of a high-power laser to create a three-dimensional shape. The laser scans each layer on a powder bed and selectively fuses them, then lowering the powder bed by one thickness and repeating the process through completion.

Multi-Jet Fusion (MJF)

Another form of Powder Bed Fusion, MJF uses a sweeping arm to deposit powder and an inkjet-equipped arm to apply binder selectively on top. Next, a detailing agent is applied around the detailing agent for precision. Finally, thermal energy is applied to cause a chemical reaction. Direct Metal Laser Sintering (DMLS) also utilizes this same process but with metal powder specifically.

Sheet Lamination

Sheet Lamination binds material in sheets through external force and welds them together through layered ultrasonic welding. The sheets are then milled in a CNC machine to form the object’s shape.

Directed Energy Deposition

Directed Energy Deposition is common in the metal industry and operates by a 3D printing apparatus attached to a multi-axis robotic arm with a nozzle for applying metal powder. The powder is applied to a surface and energy source, which then melts the material to form a solid object.

What is 3D printing? How does a 3D printer work? Learn 3D printing

3D printing or 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 instance a milling machine.

3D printing enables you to produce complex shapes using less material than traditional manufacturing methods.

Table of Contents

How Does 3D Printing Work?
3D Printing Industry
Examples of 3D Printing
3D Printing Technologies & Processes
Materials
Services

Jump to your field of interest:

Rapid Prototyping & Manufacturing
Automotive
Aviation
Construction
Consumer Products
Healthcare
Food
Education

Jump to process:

All Technologies & Processes
Vat Photopolymerisation
Material Jetting
Binder Jetting
Material Extrusion
Powder Bed Fusion
Sheet Lamination
Directed Energy Deposition

How Does 3D Printing Work?

It all starts with a 3D model. You can opt to create one from the ground up or download it from a 3D library.

3D Software

There are many different software tools available. From industrial grade to open source. We’ve created an overview on our 3D software page.

We often recommend beginners to start with Tinkercad. Tinkercad is free and works in your browser, you don’t have to install it on your computer. Tinkercad offers beginner lessons and has a built-in feature to export your model as a printable file e.g .STL or .OBJ.

Now that you have a printable file, the next step is to prepare it for your 3D printer. This is called slicing.

Slicing: From printable file to 3D Printer

Slicing basically means slicing up a 3D model into hundreds or thousands of layers and is done with slicing software.

When your file is sliced, it’s ready for your 3D printer. Feeding the file to your printer can be done via USB, SD or Wi-Fi. Your sliced file is now ready to be 3D printed layer by layer.

3D Printing Industry

Adoption of 3D printing has reached critical mass as those who have yet to integrate additive manufacturing somewhere in their supply chain are now part of an ever-shrinking minority. Where 3D printing was only suitable for prototyping and one-off manufacturing in the early stages, it is now rapidly transforming into a production technology.

Most of the current demand for 3D printing is industrial in nature. Acumen Research and Consulting forecasts the global 3D printing market to reach $41 billion by 2026.

As it evolves, 3D printing technology is destined to transform almost every major industry and change the way we live, work, and play in the future.

Examples of 3D Printing

3D printing encompasses many forms of technologies and materials as 3D printing is being used in almost all industries you could think of. It’s important to see it as a cluster of diverse industries with a myriad of different applications.

A few examples:

– consumer products (eyewear, footwear, design, furniture)
– industrial products (manufacturing tools, prototypes, functional end-use parts)
– dental products
– prosthetics
– architectural scale models & maquettes
– reconstructing fossils
– replicating ancient artefacts
– reconstructing evidence in forensic pathology
– movie props

Rapid Prototyping & Rapid Manufacturing

Companies have used 3D printers in their design process to create prototypes since the late seventies. Using 3D printers for these purposes is called rapid prototyping.

Why use 3D Printers for Rapid Prototyping?
In short: it’s fast and relatively cheap. From idea, to 3D model to holding a prototype in your hands is a matter of days instead of weeks. Iterations are easier and cheaper to make and you don’t need expensive molds or tools.

Besides rapid prototyping, 3D printing is also used for rapid manufacturing. Rapid manufacturing is a new method of manufacturing where businesses use 3D printers for short run / small batch custom manufacturing.

Automotive

Car manufacturers have been utilizing 3D printing for a long time. Automotive companies are printing spare parts, tools, jigs and fixtures but also end-use parts. 3D printing has enabled on-demand manufacturing which has lead to lower stock levels and has shortened design and production cycles.

Automotive enthusiasts all over the world are using 3D printed parts to restore old cars. One such example is when Australian engineers printed parts to bring a Delage Type-C back to life. In doing so, they had to print parts that were out of production for decades.

Aviation

Aviation loves additive manufacturing, largely due to the promise of lightweight and stronger structures offered by 3D printing. We’ve seen a whole bunch of innovations in the domain of aviation lately, with the appearance of more critical parts being printed.

Turbine Center Frame

One such large component printed this year was the turbine center frame which was printed by GE as part of the EU Clean Sky 2 initiative.

The Advanced Additive Integrated Turbine Centre Frame (TCF) is a 1 meter diameter part printed in nickel alloy 718 by GE and a consortium from Hamburg University of Technology (TUHH), TU Dresden (TUD) and Autodesk. It is one of the largest single metal parts printed for aviation.

Big turbine center frame. (Image credit: GE AAT Munich)

Typically components like this are manufactured using casting, and consist of multiple parts. In the case of the 3D printed version, it was reduced from an assembly of 150 parts down to just 1 single piece. The printed version also benefits from a reduction of both cost and mass by 30%, and a reduction in lead time from 9 months to just 10 weeks.

Metal Parts Certified by EASA

Back in June 2022 it was reported that Lufthansa Technik and Premium AEROTEC had created the first load-bearing metal part that had been approved for use in aviation.

The new A-link was produced using LPBF and had demonstrated higher tensile strength compared to the traditionally-forged version.

The part was made at Premium AEROTEC’s facility in Varel, Germany, and a large number of test parts were printed and tested to ensure quality and repeatability for certification.

Printed titanium A-links (Image credit: Lufthansa Technik)

Printing the part represented a cost saving for the component and set the stage for using this manufacturing method for creating structurally important metal parts in the future. It was also used to test the process and to demonstrate the certification process of load-bearing AM parts.

Hypersonic Fuel Injector

This next printed item was never destined to be fitted to an aircraft, but rather it was designed to be installed in a facility for testing flow conditions at hypersonic speeds.

When flying in the hypersonic flight regime above (Mach 5), the air passing around the vehicle becomes incredibly hot, and the pressure increases significantly. These conditions can cause the air itself to become chemically reactive, which causes issues for fuel burning vehicles.

Simulating flow conditions with CFD is computationally expensive (if not impossible), and so to replicate the flow conditions, researchers at Purdue fabricated a giant burner to recreate the hot, fast, high pressure experienced in hypersonic flight. In short, they basically built a rocket nozzle and they placed the test components in the exhaust plume to see how they performed.

3D Printed Fuel Injectors (Image credit: Purdue University)

The injectors that they printed feed fuel and air into the combustion chamber to create specific turbulent flow fields and a stable flame.

The injectors were printed with Hastelloy X, which is a superalloy with superior temperature resistance. The team printed multiple different injectors in rapid time, and tested them all in the burner to see which performed the best.

Now they are able to replicate the hypersonic conditions for flight on Earth at a fraction of the cost (and risk) associated with doing it miles above the Earth’s surface. This can benefit fast aircraft such as scramjet powered vehicles as well as space vehicles.

Relativity Space

We have covered US-based rocket printing company Relativity Space quite a lot on this website.

From their super large metal printer the “Stargate” to the rocket themselves, this company has been doing big things with both printing and rockets. The 4th gen Stargate 3D printer is capable of printing objects measuring 120ft long and 24ft in diameter, and 12x faster than their previous printers.

The new AI-assisted robotic printer has been able to achieve faster printing speeds thanks to its innovative multi-wire print head. This print head allows for multiple metal feedstock wires to be fed into it at the same time, resulting in higher deposition rates.

The company is scheduled to make their first LEO test flight of the printed Terran-1 rocket this month of January 2023, so we just thought we would give them an honorable mention in this article as a reminder.

You can see the Terran-1 undergoing a hot fire test in the video below.

Construction

Is it possible to print a building? – yes it is. 3D printed houses are already commercially available. Some companies print parts prefab and others do it on-site.

Most of the concrete printing stories we look at on this website are focused on large scale concrete printing systems with fairly large nozzles for a large flow rate. It’s great for laying down concrete layers in a fairly quick and repeatable manner. But for truly intricate concrete work that makes full use of the capabilities of 3D printing requires something a little more nimble, and with a finer touch.

Consumer Products

When we first started blogging about 3D printing back in 2011, 3D printing wasn’t ready to be used as a production method for large volumes. Nowadays there are numerous examples of end-use 3D printed consumer products.

Footwear

Adidas’ 4D range has a fully 3D printed midsole and is being printed in large volumes. We did an article back then, explaining how Adidas were initially releasing just 5,000 pairs of the shoes to the public, and had aimed to sell 100,000 pairs of the AM-infused designs by 2018.

With their latest iterations of the shoe, it seems that they have surpassed that goal, or are on their way to surpassing it. The shoes are available all around the world from local Adidas stores and also from various 3rd party online outlets.

Eyewear

The market of 3D printed eyewear is forecasted to reach $3.4 billion by 2028. A rapidly increasing section is that of end-use frames. 3D printing is a particularly suitable production method for eyewear frames because the measurements of an individual are easy to process in the end product.

But did you know it’s also possible to 3D print lenses? Traditional glass lenses don’t start out thin and light; they’re cut from a much larger block of material called a blank, about 80% of which goes to waste. When we consider how many people wear glasses and how often they need to get a new pair, 80% of those numbers is a lot of waste. On top of that, labs have to keep huge inventories of blanks to meet the custom vision needs of their clients. Finally, however, 3D printing technology has advanced enough to provide high-quality, custom ophthalmic lenses, doing away with the waste and inventory costs of the past. The Luxexcel VisionEngine 3D printer uses a UV-curable acrylate monomer to print two pairs of lenses per hour that require no polishing or post-processing of any kind. The focal areas can also be completely customized so that a certain area of the lens can provide better clarity at a distance while a different area of the lens provides better vision up close.

Jewelry

There are two ways of producing jewelry with a 3D printer. You can either use a direct or indirect production process. Direct refers to the creation of an object straight from the 3D design while indirect manufacturing means that the object (pattern) that is 3D printed eventually is used to create a mold for investment casting.

Healthcare

It’s not uncommon these days to see headlines about 3D printed implants. Often, those cases are experimental, which can make it seem like 3D printing is still a fringe technology in the medical and healthcare sectors, but that’s not the case anymore. Over the last decade, more than 100,000 hip replacements have been 3D printed by GE Additive.

The Delta-TT Cup designed by Dr. Guido Grappiolo and LimaCorporate is made of Trabecular Titanium, which is characterized by a regular, three-dimensional, hexagonal cell structure that imitates trabecular bone morphology. The trabecular structure increases the biocompatibility of the titanium by encouraging bone growth into the implant. Some of the first Delta-TT implants are still running strong over a decade later.

Another 3D printed healthcare component that does a good job of being undetectable is the hearing aid. It is estimated that 99% of hearing aids manufactured are made with the use of additive manufacturing, and it’s clear to see why.

Dental

In the dental industry, we see molds for clear aligners being possibly the most 3D printed objects in the world. Currently, the molds are 3D printed with both resin and powder based 3D printing processes, but also via material jetting. Crowns and dentures are already directly 3D printed, along with surgical guides.

Bio-printing

As of the early two-thousands 3D printing technology has been studied by biotech firms and academia for possible use in tissue engineering applications where organs and body parts are built using inkjet techniques. Layers of living cells are deposited onto a gel medium and slowly built up to form three dimensional structures. We refer to this field of research with the term: bio-printing.

Food

Additive manufacturing invaded the food industry long time ago. Restaurants like Food Ink and Melisse use this as a unique selling point to attract customers from across the world.

Education

Educators and students have long been using 3D printers in the classroom. 3D printing enables students to materialize their ideas in a fast and affordable way.

While additive manufacturing-specific degrees are fairly new, universities have long been using 3D printers in other disciplines. There are many educational courses one can take to engage with 3D printing. Universities offer courses on things that are adjacent to 3D printing like CAD and 3D design, which can be applied to 3D printing at a certain stage.

In terms of prototyping, many university programs are turning to printers. There are specializations in additive manufacturing one can attain through architecture or industrial design degrees. Printed prototypes are also very common in the arts, animation and fashion studies as well.

Types of 3D Printing Technologies and Processes

The American Society for Testing and Materials (ASTM), developed a set of standards that classify additive manufacturing processes into 7 categories. These are:

Vat Photopolymerisation
1. Stereolithography (SLA)
2. Digital Light Processing (DLP)
3. Continuous Liquid Interface Production (CLIP)
Material Jetting
Binder Jetting
Material Extrusion
1. Fused Deposition Modeling (FDM)
2. Fused Filament Fabrication (FFF)
Powder Bed Fusion
1. Multi Jet Fusion (MJF)
2. Selective Laser Sintering (SLS)
3. Direct Metal Laser Sintering (DMLS)
Sheet Lamination
Directed Energy Deposition

Vat Photopolymerisation

A 3D printer based on the Vat Photopolymerisation method has a container filled with photopolymer resin. The resin is hardened with a UV light source.

Vat photopolymerisation schematics. Image source: lboro.ac.uk

Stereolithography (SLA)

SLA was invented in 1986 by Charles Hull, who also at the time founded the company, 3D Systems. Stereolithography employs a vat of liquid curable photopolymer resin and an ultraviolet laser to build the object’s layers one at a time. For each layer, the laser beam traces a cross-section of the part pattern on the surface of the liquid resin. Exposure to the ultraviolet laser light cures and solidifies the pattern traced on the resin and fuses it to the layer below.

After the pattern has been traced, the SLA’s elevator platform descends by a distance equal to the thickness of a single layer, typically 0.05 mm to 0.15 mm (0.002″ to 0.006″). Then, a resin-filled blade sweeps across the cross section of the part, re-coating it with fresh material. On this new liquid surface, the subsequent layer pattern is traced, joining the previous layer. Depending on the object & print orientation, SLA often requires the use of support structures.

Digital Light Processing (DLP)

DLP or Digital Light Processing refers to a method of printing that makes use of light and photosensitive polymers. While it is very similar to SLA, the key difference is the light source. DLP utilizes other light sources like arc lamps. DLP is relatively quick compared to other 3D printing technologies.

Continuous Liquid Interface Production (CLIP)

One of the fastest processes using Vat Photopolymerisation is called CLIP, short for Continuous Liquid Interface Production, developed by Carbon.

Digital Light Synthesis

The heart of the CLIP process is Digital Light Synthesis technology. In this technology, light from a custom high performance LED light engine projects a sequence of UV images exposing a cross section of the 3D printed part causing the UV curable resin to partially cure in a precisely controlled way. Oxygen passes through the oxygen permeable window creating a thin liquid interface of uncured resin between the window and the printed part known as the dead zone. The dead zone is as thin as ten of microns. Inside the dead zone, oxygen prohibits light from curing the resin situated closest to the window therefore allowing the continuous flow of liquid beneath the printed part. Just above the dead zone the UV projected light upwards causes a cascade like curing of the part.

Simply printing with Carbon’s hardware alone does not allow for end use properties with real world applications. Once the light has shaped the part, a second programmable curing process achieves the desired mechanical properties by baking the 3d printed part in a thermal bath or oven. Programmed thermal curing sets the mechanical properties by triggering a secondary chemical reaction causing the material to strengthen achieving the desired final properties.

Components printed with Carbon’s technology are on par with injection molded parts. Digital Light Synthesis produces consistent and predictable mechanical properties, creating parts that are truly isotropic.

Material Jetting

In this process, material is applied in droplets through a small diameter nozzle, similar to the way a common inkjet paper printer works, but it is applied layer-by-layer to a build platform and then hardened by UV light.

Material Jetting schematics. Image source: custompartnet.com

Binder Jetting

With binder jetting two materials are used: powder base material and a liquid binder. In the build chamber, powder is spread in equal layers and binder is applied through jet nozzles that “glue” the powder particles in the required shape. After the print is finished, the remaining powder is cleaned off which often can be re-used printing the next object. This technology was first developed at the Massachusetts Institute of Technology in 1993.

Binder Jetting schematics

Material Extrusion

Fused Deposition Modeling (FDM)

FDM schematics (Image credit: Wikipedia, made by user Zureks)

FDM works using a plastic filament which is unwound from a spool and is supplied to an extrusion nozzle which can turn the flow on and off. The nozzle is heated to melt the material and can be moved in both horizontal and vertical directions by a numerically controlled mechanism. The object is produced by extruding melted material to form layers as the material hardens immediately after extrusion from the nozzle.

FDM was invented by Scott Crump in the late 80’s. After patenting this technology he started the company Stratasys in 1988. The term Fused Deposition Modeling and its abbreviation to FDM are trademarked by Stratasys Inc.

Fused Filament Fabrication (FFF)

The exactly equivalent term, Fused Filament Fabrication (FFF), was coined by the members of the RepRap project to give a phrase that would be legally unconstrained in its use.

Powder Bed Fusion

Selective Laser Sintering (SLS)

SLS uses a high power laser to fuse small particles of powder into a mass that has the desired three dimensional shape. The laser selectively fuses powder by first scanning the cross-sections (or layers) on the surface of a powder bed. After each cross-section is scanned, the powder bed is lowered by one layer thickness. Then a new layer of material is applied on top and the process is repeated until the object is completed.

SLS schematics (Image credit: Wikipedia from user Materialgeeza)

Multi Jet Fusion (MJF)

Multi Jet Fusion technology was developed by Hewlett Packard and works with a sweeping arm which deposits a layer of powder and then another arm equipped with inkjets which selectively applies a binder agent over the material. The inkjets also deposit a detailing agent around the binder to ensure precise dimensionality and smooth surfaces. Finally, the layer is exposed to a burst of thermal energy that causes the agents to react.

Direct Metal Laser Sintering (DMLS)

DMLS is basically the same as SLS, but uses metal powder instead. All unused powder remains as it is and becomes a support structure for the object. Unused powder can be re-used for the next print.

Due to of increased laser power, DMLS has evolved into a laser melting process. Read more about that and other metal technologies on our metal technologies overview page.

Sheet Lamination

Sheet lamination involves material in sheets which is bound together with external force. Sheets can be metal, paper or a form of polymer. Metal sheets are welded together by ultrasonic welding in layers and then CNC milled into a proper shape. Paper sheets can be used also, but they are glued by adhesive glue and cut in shape by precise blades.

Simplified schematics of ultrasonic sheet metal process (Image credit: Wikipedia from user Mmrjf3)

Directed Energy Deposition

This process is mostly used in the metal industry and in rapid manufacturing applications. The 3D printing apparatus is usually attached to a multi-axis robotic arm and consists of a nozzle that deposits metal powder or wire on a surface and an energy source (laser, electron beam or plasma arc) that melts it, forming a solid object.

Directed Energy Deposition with metal powder and laser melting (Image credit: Merlin project)

Materials

Multiple materials can be used in additive manufacturing: plastics, metals, concrete, ceramics, paper and certain edibles (e.g. chocolate). Materials are often produced in wire feedstock a.k.a. filament, powder form or liquid resin. Learn more about our featured materials on our materials page.

Services

Looking to implement 3D printing in your production process? Get a quote for a custom part or order samples on our 3D print service page.

How a 3D printer works, what can be printed on a 3D printer

The 3D printer is a technology that allows you to create real objects from a digital model. It all started in the 80s under the name "rapid prototyping", which was the goal of the technology: to create a prototype faster and cheaper. A lot has changed since then, and today 3D printers allow you to create anything you can imagine.

Contents:

What is 3D printing?
How does a 3D printer work?
What can be printed?

The 3D printer allows you to create objects that are almost identical to their virtual models. That is why the scope of these technologies is so wide.

What is 3D printing?

3D printing is an additive manufacturing process because, unlike traditional subtractive manufacturing, 3D printing does not remove material, but adds it, layer by layer—that is, it builds or grows.

In the first step of printing, the data from the drawing or 3D model is read by the printer.
Next is the sequential overlay of layers.
These layers, consisting of sheet material, liquid or powder, are combined with each other, turning into the final form.

With limited production of parts, 3D printing will be faster and cheaper. The world of 3D printing does not stand still and therefore there are more and more different technologies competing with each other on the market. The difference lies in the printing process itself. Some technologies create layers by softening or melting the material, then they provide layer-by-layer application of this same material. Other technologies involve the use of liquid materials, which acquire a solid form in the process under the influence of various factors.

In order to print something , you first need a 3D model of the object, which you can create in a 3D modeling program (CAD - Computer Aided Design), or use a 3D scanner to scan the object you want print. There are also easier options, such as looking for models on the internet that have been created and made available to other people.

Once your design is ready, all you need to do is import it into the Slicer, a program that converts the model into codes and instructions for a 3D printer, most of the programs are open source and free. The slicer will convert your project into a gcode file ready to be printed as a physical object. Simply save the file to the included SD card and insert it into your 3D printer and hit print.

The whole process can take several hours and sometimes several days. It all depends on the size, material and complexity of the model. Some 3D printers use two different materials. One of them is part of the model itself, the other acts as a prop that supports parts of the model hanging in the air. The second material is subsequently removed.

How does a 3D printer work?

Although there are several 3D printing technologies, most create an object by building up many successive thin layers of material. Typically desktop 3D printers use plastic filaments (1) which are fed into the printer by the feeder (2) . The filament melts in the print head (3) which extrudes the material onto the platform (4) creating the object layer by layer. Once the printer starts printing, all you have to do is wait - it's easy.

Of course, as you become an advanced user, playing with the settings and tweaking your printer can lead to even better results.

What can be 3D printed?

The possibilities of 3D printers are endless and they are now becoming a common tool in fields such as engineering, industrial design, manufacturing and architecture. Here are some typical usage examples:

Custom Models

Create custom products that perfectly match your needs in terms of size and shape. Do something that would be impossible with any other technology.

Rapid Prototyping

3D printing allows you to quickly create a model or prototype, helping engineers, designers and companies get feedback on their projects in a short time.

Complex geometry

Models that are hard to imagine can be easily created with a 3D printer. These models are good for teaching others about complex geometry in a fun and useful way.

Cost reduction

The cost of 3D printing end-use parts and prototypes is low due to the materials and technology used. Reduced production time and material consumption as you can print models multiple times using only the material you need.

How to choose and buy a 3D printer? →

How does a 3D printer work and what is it for - Code magazine

Over the past couple of years, there has been a lot of news about someone printing something on a 3D printer:

hearing aid,
milk products,
residential building,
robotic fingers,
brain implants,
1mm statue of David,
prefabricated electronic devices.

Let's figure out how this technology works, what its limitations are and whether it has a future.

What a 3D printer is for

3D printers print three-dimensional things from plastic or other materials. They can be used at home or in production. For example, here is what you can 3D print:

Battery case. Hinged LED lamp. Minecraft style lamp. Model of an old castle.

How it works

Usually a 3D printer uses special plastic to print. It comes in the form of powder, liquid resin or plastic wire in coils. It is from this material that the printed part will consist.

Further, roughly speaking, the process looks like this:

this plastic is either applied using a moving nozzle;
or "baked" with a laser;
or the excess is cut out of the mass of the finished material using a movable cutter (but this is more like turning and is often not classified as 3D printing).

The material takes on the shape you want, layer by layer. When all layers are passed, the detail turns out.

Fast 3D Printing with Moving Nozzle:

Due to the fact that the printer needs to constantly heat the plastic, 3D printers do not print very quickly: a part the size of a phone can take 15-20 minutes. The speed also depends on the thickness of the layer: the thicker the layer, the faster the print. But with a large layer thickness, the part may turn out to be sloppy: layers will be visible:

The thinner the layer, the more even the surface is when printed.

Printing Technologies

3D printing is very much needed in industry and industrial design, so there is a whole zoo of printing technologies, each with its own advantages and disadvantages.

Stereolithography . Instead of plastic, a special resin is used here, which hardens in the light. The detail is also formed in layers, but the layers themselves are almost invisible - the resin fills the relief and the detail seems to be a single whole even from a very close distance.

Polymer synthesis (SLS) . This type of printing uses powder, which is then baked with a laser beam. Since the laser beam can be focused anywhere with the desired accuracy, very complex models with high detail can be obtained in this way of printing:

Polyjet. The peculiarity of this technology is that it can print objects simultaneously from different materials. This allows you to create almost any thing of the most complex shape, which immediately have the desired properties. You can even print sneakers that you can wear on this printer:

What can be printed

Anything can be printed on a 3D printer if you have the right material for printing, a finished model and a large enough printer.

Prototypes. Often, before starting production, a company needs to understand how comfortable a thing will turn out to be in use. In order not to launch a line for the sake of one product, it is printed on a 3D printer and they look at what needs to be changed or finalized. On such prototypes, you can notice, for example, that the buttons turned out to be too small and it would be inconvenient to press them, or that the buttons turned out to be very far from the fingers and you will need to reach them specially.

Parts and parts. Sometimes it is difficult or almost impossible to find a spare part for a tool: the manufacturer does not produce them or the model has been out of production for a long time. In this case, you can find a three-dimensional model of the desired part on the Internet or draw it yourself in the editor, so that you can then send it to print.

Medicine. 3D printing is actively used in medicine to create new joints, tissues and treat patients. The difference from traditional printing is that instead of plastic, they print with special “living” solutions that interact with each other and behave like real organs and tissues. Thanks to this technology, it is now easy to print a joint that a surgeon can put on a person instead of a damaged one.

Hobbies and modeling. It is easy to print various miniatures, collectible figurines and models with a 3D printer.

Manufacture of other robots. 3D printers do not yet know how to produce servos and microprocessors, but they already know how to print bodies and frames of robots.

Houses and buildings. We take hefty rails with motors and controllers. We install a movable nozzle, on which you can supply a building mixture (concrete or polymers). You can print the walls of buildings. Unlike traditional brick, panel and block construction technologies, the shape of the walls and the building as a whole can be any. The foundation, floors and roof are not yet printed, but this is for now.

Imagine: we send fifty 3D printers on a mobile basis to Mars. For a year, each of them prints another 100 printers. Then all these 5,000 printers disperse around Mars and begin to build the first colony. While they are building, we order furniture from Ikea, arrange delivery, and just in time for delivery, our robots will finish printing everything. Apple trees on Mars are unlikely to bloom, but five-story buildings can.

Criticisms and issues

❌ Slow and no guarantees: printing is quite slow, not accurate enough. A huge problem in amateur printers is marriage. For example, a part can peel off the substrate right during printing, and hell will happen. Or the motors will decalibrate, and the nozzle will begin to miss the right places.

❌ Low efficiency: to print a 10 x 10 cm part, you need a printer that is at least 50 x 50 cm, which will cost several hundred dollars.

❌ Not the strongest materials: 3D printing is currently limited to plastics and resins. There are separate printing technologies based on metal powder, but if you need a steel part, you don’t need a 3D printer, but a normal turner and machine tool. But not every detail can be made on the machine.