An Introduction to 3D Printing - Part I
March 20, 2013
According to one of the most powerful people in the world, 3D Printing “has the potential to revolutionize the way we make almost everything”. Speaking at the State of the Union address in February of this year, President Barack Obama revealed himself to be one of the many proponents of 3D printing and its potential to change the way we make things.
That’s all very well and good, but what is 3D printing? What’s all the hype about? Why are we writing about it?
The answers to the first two questions will be addressed later in this blog, but we thought it would be pertinent to quickly introduce the reasoning why we’ve dedicated a few thousand words to the technology up front.
3D printing is a technology that’s close to RHA for a number of reasons, principally, that it is an integral part of our product design and pre-manufacturing processes. RHA has been using 3D printing to develop prototypes of our products since the company’s founding and invested in the technology at an early stage to be one of the first headphone manufacturers to make use of 3D printing’s many advantages for consumer electronics companies. We’ll discuss the specific applications of 3D printing at RHA later on in this blog, so keep reading.
Now for the other questions, if you already have an idea what 3D printing is all about but want to know a little more about how it works or how it can be used; if your eye has been caught by an outlandish headline about a 3D printing project that seems unfeasible and wondered if its achievable or if you’ve simply just heard the name this blog is for you. We’re covering all the bases to ensure that anyone can get up to speed with technology’s ‘next big thing’. So dive in, read on, and enjoy!
So what is it?
3D printing is a method of creating physical objects from digital 3D drawings; and unlike typical manufacturing processes, 3D printing is an additive process. Additive manufacturing means that rather than taking a block of material and removing parts of it to create an object (subtractive manufacturing or machining), an object is built up from nothing, adding substance to create a fully realised shape. There are a number of methods of 3D printing, each using slightly different technologies, but all adhering to the additive manufacturing principle.
How exactly does it work?
3D printing uses cross-sections of objects to build them up in layers. The first 3D printing method was developed in 1986 by Charles Hull, founder of 3D printing company 3D Systems. He created stereolithography (SLA), a form of 3D printing which uses a vat of UV sensitive, plastic resin. The liquid plastic is subjected to a UV laser which traces a shape of an object’s cross section across the surface of the liquid, curing and hardening it. The base of the vat then descends to lower the solid, cured plastic below the level of the liquid plastic so that the process can be repeated and another layer of plastic lasered and cured on top.
A second method of 3D printing, known as Fused Deposition Modeling (FDM), was developed shortly after stereolithography. FDM is similar to stereolithography in that both primarily use plastic as a source material, however FDM uses an inkjet-style printhead to draw layers of an object from molten strands of plastic which fuse together as the material hardens.
Whilst there are a number of other 3D printing technologies emerging (including the excitingly named Selective Laser Sintering), FDM and SLA are the most prevalent. FDM is the most commonly used printing method for non-commercial 3D printing; it is by far the cheapest method, and the printer hardware is usually of relatively small size. SLA is used mostly by industrial grade machines and offers greater speed, reliability and strength properties of the objects produced. SLA objects are often strong and accurate enough to be machined and used as prototypes of objects to be later manufactured using injection molding techniques, something we’ll discuss in greater detail later.
How did we get to today?
FDM and SLA underwent intensive development in the late 1980s and early 1990s, however it was not until the final few years of the twentieth century that 3D printers had advanced out of the prototyping stage and could be made available to the public. Three different companies released 3D printers in the late nineties - Stratasys (the company responsible for developing the FDM printing method) 3D Systems, and Z Corp.
Once the first 3D printers were on the market, the technology received more and more attention, leading to more research, which in turn lead to drastic improvements in the efficiency and cost effectiveness of 3D printers in the early 2000s. Founded in 2006, the RepRap project is an open source, collaborative initiative started by the University of Bath with the aim of creating the world’s first self-replicating 3D printer. Their first printer, the Darwin, was released in 2008, utilising a variation of FDM technology. The Darwin was capable of reproducing over 50% of its own parts and its successors capable of producing even more, which helped reduced the cost and greatly quickened the spread of early home 3D printers.
The current state of 3D printing could be described as at late-stage early adoption. The consumer 3D printer marketplace is becoming crowded, and online and local 3D printing centres that users can send designs for professional printing are becoming more and more common. There’s a wide variety of companies attempting to get onboard with technology’s ‘next big thing’, but are their efforts in vain? Will 3D printing instigate major change in the way we manufacture, interact with and repair objects? To answer these questions we need to look at what 3D printers are capable of.
What can they do?
The current applications of 3D printers are slightly limited, but there are examples of fantastic things being created within the confines of the current abilities of the technology and exciting theories regarding how 3D printing could be used in the future when the technology advances.
One of the most useful things that 3D printing can produce at the moment are small, precise components for equipment. The additive manufacturing process has the potential to be much, much more accurate than traditional methods, meaning intricate, mechanical parts for machines can be created with a much greater degree of accuracy.
Similarly, 3D printing product prototypes has become a common practice for industries making consumer electronics. We mentioned earlier that RHA uses 3D printing to manufacture prototypes of new products, product parts and components. Using a SLA 3D printer for prototyping gives our design team the opportunity to experience the aesthetic and functional properties of a design before committing to manufacturing on a large scale. Where normally a factory tooled prototype would take several weeks to produce, the speed and convenience of 3D printing means our that designers have the opportunity to create completely unique designs and test them within hours of making their first sketches, and can refine the design based on the first prototype before printing another prototype just as quickly.
3D printing also has applications in the field of medicine. 3D printing is already being used to create replacement bones, and there are some incredibly exciting advances being made in the field of stem cell printing. In January of this year, Edinburgh’s Heriot Watt University announced it had successfully 3D printed human stem cells using bio-ink. This breakthrough is effectively the first, small step towards 3D printed human organs created using the host’s own DNA. 3D printed organs could eliminate the need for organ donors and greatly reduce the risk of host rejection.
Currently, the most common use of 3D printing, especially in regards to consumer 3D printers, tends to be small scale craftwork and art projects. The technology, despite its recent significant advances, is yet to reach a stage that the average consumer is able to create a particularly wide range of meaningful products. There are examples of bigger 3D printing projects including guitars, clothes and even headphones, but for the most part, these items exist as one-offs and novelties - experiments to illustrate what the technology could be capable of.
At the other end of the scale, media outlets are often quick to pick up stories about large scale 3D printing projects such as cars and houses. These are projects which are far from being a reality, yet capture the imagination of the public because of the hype around technology. Like every major technological advancement, there are companies racing to be the first to market with a new version of it, or a new way to use it, and large scale projects such as these are likely to generate publicity for the companies behind them, if nothing else.
So what are the pros and cons of 3D printing? Why is the technology the subject of so much hype? Revisit the RHA blog next week, as we’ll be discussing the benefits and drawbacks of 3D printing in its current state and those that might arise in the future and trying to figure out just whether 3D printing could be the catalyst for the next manufacturing revolution.
Image courtesy of U.S. Army Materiel Command