What is 3D printing? Understanding the technology that’s changing the way we manufacture everyday objects

• 3D printing creates solid objects from the additive process of layering plastics, metal, wood, synthetic fibers, and more.
• You can 3D-print your own designs using a digital program or download ready-made plans from the internet.
• 3D-printing technology will continue to change the way we make objects, but it is not without ethical, legal, and environmental concerns.
• Visit Insider's Tech Reference library for more stories.

3D printing technology is changing the way we manufacture everything from toys and clothes to human tissue.

The process of printing a three-dimensional object is known as additive manufacturing. A computer program tells the printer where to apply thin layers of materials to build a solid object.

Types of 3D printing technologies and processes

3D printing technology dates to the early 1980s, when Japanese inventor Hideo Kodama used UV light to harden plastics to create an object using this additive technology.

Years later, American Scott Crump developed the most common type of 3D printing today, known as fused deposition modeling (or FDM), where thermoplastic is heated to a liquid and then applied layer by layer. This is what's most commonly seen on workbenches and office desks.

Charles Hull, the co-founder of 3D Systems, was one of the inventors behind the 3D printing application known as stereolithography, which uses photochemical processes.

Kodama, Crump, and Hull weren't the only ones to develop 3D printing methods, however.

Here are some of the other forms of 3D printing in use today:

• Selective laser sintering (SLS) melts nylon powders into a durable solid plastic. The finish is not beautiful, but incredibly functional, and is useful for prototype designs with "hinges" and "snap-fits."
• PolyJet can 3D-print objects with multiple colors and materials. The flexibility makes this process more expensive and not ideal for simpler plastic designs.
• Digital light processing (DLP) hardens polymers using a light projector, rather than a UV laser. That allows it to build an entire layer of an object at once, increasing build speed.

Metal has its own methods for 3D printing, all for different applications:

• Direct metal laser sintering (DMLS) is useful for creating ornate individual parts. That makes it a go-to for medical applications and lightweight designs. This method is often used in conjunction with more traditional metal casting to create one final object or prototype design.
• Electron beam melting (EBM) employs electromagnetic coils to superheat metal powder in a vacuum when printing.

How 3D printing works

The 3D printing process is all about applying layers one by one, but every 3D-printed object begins as a three-dimensional blueprint in a computer program.

You can build your own design in software such as Maya, Blender, or ZBrush. You can also download a ready-made design from Thingiverse or CGTrader.

Once you have your model you can run it through a slicer like Cura, a program that takes the file and creates a code of thousands of layers to direct the printer how to print.

Then you have to set up your printer, choose the quality of the print and the correct material settings. From there you can upload your sliced file to the printer with a USB drive, SD card, or a program such as OctoPrint. Then the printer begins the sometimes slow, additive process of applying material layer by layer.

What 3D printing is used for

If you can dream up an object, especially if it's plastic, you are likely able to 3D print it. Think toys, jewelry, models, phone cases, molds, and more. There are some particularly fun designs, including a 3D-printed guitar, a loom, and an intricate sculpture made with a combination of glass and nylon fused together with a laser.

3D printing has evolved beyond its origins in plastics to print metals, rubber, wood, synthetic fabrics, and ceramic resin. Functional, 3D-printed human organs remain a work in progress, but scientists say it's in our future.

Because additive manufacturing is both cheaper and faster than traditional methods like molding or sculpting, it's becoming popular in both manufacturing and the arts. The possibilities are practically endless, but 3D printers are not perfect machines. In fact, there are plenty of concerns.

3D printers introduce ethical issues

3D printers use a lot of energy and disperse ultrafine plastic particles into the air that can be inhaled. These harmful emissions are comparable to a lit cigarette indoors.

At a time when people are trying to curb our use of plastics, 3D printers are just one more technology reliant on them. That's an environmental concern for all ecosystems, but particularly to our already struggling oceans currently filled with microplastics.

Years ago, news of the first 3D-printed gun caused a media frenzy, and individuals creating untraceable weapons remains a safety concern.

Legally, there are no clear answers about who is liable when someone is harmed by a 3D-printed object because the model designer, 3D printer manufacturer, and the person who printed the object are often different entities. Determining who is responsible for potential injuries and death is a new quandary.

Additionally, the use of 3D printing technology in the medical field for 3D tissues introduces a spate of ethical and moral concerns similar to decadeslong conversations around stem cell research and gene editing.

Any way you look at it, we have a radically powerful tool at our disposal that changes how we make and obtain things. We don't yet know what it means for our future.

Where you can use a 3D printer

While owning your own 3D printer and the necessary software and materials may be too expensive for an individual's needs, public 3D printers are becoming more commonplace, especially if you live in an urban area.

There are such things as 3D printing labs and stores. You can send a design and pick it up in a matter of days. Some big box stores like Staples do 3D printing, too.

If you're a student, you may have 3D printing services at your school. Your local library may also offer 3D printing.

But if you can't find anything nearby, you can order a 3D-printed object online from a service like Protolabs or Fictiv.

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