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  • 3D Printing – A Self-Replicating Design for Rapid Prototyping.and Inspiring Innovation

3D Printing – A Self-Replicating Design for Rapid Prototyping.and Inspiring Innovation

"3D printing is fast becoming an essential part

of the design process. Increasing numbers of companies are beginning to see the benefits of using this technology to create quick-turn- around prototypes and save months in the design cycle."

 

Barriers to adoption in the past have been the cost of hardware and a lack of easy-to-use design software for non-CAD specialists. Now, the RepRap open-source self-replicating3D printer initiative has culminated in the latest Ormerod 3D printer. In conjunction with the DesignSpark Mechanical 3D modelling software tool, it presents companies and developers with a massive opportunity both to shorten the product development process and inspire innovation, writes Mark Cundle, Head of Technical Marketing at RS Components.

Three-dimensional (3D) printing, or additive manufacturing as it is also called, is revolutionising product development, and also production in some cases. It is the process of making a solid object from a computer-aided- design (CAD) model, achieved using an additive manufacturing process, essentially building up successive layers of materials such as plastic or metals that are laid down in different shapes. The more traditional machining technique of course uses a subtractive process, involving the removal of materials – in an approximately similar way to that adopted by sculptors chopping off whatever they didn’t need from their chosen block of marble, to paraphrase Auguste Rodin.

While 3D printing has really come to the attention of the general public over the past year or so (some partly due to headlines about weapon manufacture unfortunately), it has actually been around since the 1980s. Many 3D printing methods have been used

such as Fused Disposition Modelling (FDM), which is the most common process used today in low-cost 3D printing, along with Stereo Lithography (SLA), Electron Beam Melting (EBM), Laminated Object Manufacturing

(LOM), among many others. These technologies are increasingly being used for rapid prototyping and also some manufacturing across a myriad of industries including engineering, construction, automotive, defence and aerospace, medical applications and a number of consumer industries such as fashion.

 

Increasing Ubiquity

Since the turn of the millennium, there has been a significant growth in sales for 3D printers, which are becoming increasingly attractive with substantial reductions in price – mass-market models are now being priced at less than $2500 and below. A recent market research report, published by analyst Markets&Markets, forecasts a CAGR of 23% for 3D printers from 2013 to 2020, eventually reaching $8.41 billion.

3D printing is moving from a niche technology used primarily by larger companies into a mass market for consumers and small businesses.

In fact, there is a now an increasing line of thought that says a 3D printer could even eventually find a corner in our homes enabling us to avoid costs associated with purchasing common household objects. The technology is fast becoming available to all and individuals will be able to make small numbers of products that are comparable to those from large companies.

There is a rather good quote related to all this, made a few months ago by dotcom pioneer Joe Kraus on the BBC Radio 4 programme ‘In Business’, essentially delivering a high level view on the current revolution in manufacturing and production: “The 20th Century was about dozens of markets of millions of consumers. The 21st Century is about millions of markets of dozens of consumers.” There is every chance that 3D printing, in conjunction with other technologies and movements such as open source, is destined to play an important part in a future that is likely to see uniqueness and increased customisation rather than the one-size-fits-all manufacturingapproach of old.

 

Rapid Prototyping – Hours Not Weeks

3D printing is certainly making an impact in mainstream product manufacturing in many industries, especially in low-volume or highly customised applications, but technology has its limits for high-volume production. 3D printing technology, which is used to create products in layers means that the structural integrity of components may not be strong enough to be used in production parts. 3D printing is therefore unlikely to replace manufacturing involving moulded liquid metal, at least any time soon. But perhaps the critical point, at least for volume manufacturing, is 3D printing’s ability to build prototypes rapidly. It is revolutionising product development – machine skills are not required to deliver prototypes, enabling huge time-to-market benefits as well as delivering a significant increase in design freedom.

There has been significant improvement in the product- development process across a wide range of industries, including car manufacturing, consumer electronics and medical devices. 3D printing technology is being used to design and test new concepts in companies both large and small as an alternative to employing custom machine tools to make early prototypes of new parts or components. The method allows product developers to have a prototype in a matter of hours or days compared with weeks or months previously.

But the process offers more than just saving time and cost; rapid prototyping using 3D printing is producing more innovative and higher quality products. Product developers no longer have to wait for tools or parts to come back from outside machine shops or injection-moulding houses. 3D printers allow the physical testing and further refining and improving of prototypes before committing a product to mass production.

 

 

What if a 3D printer could create a duplicate of itself?

 

RepRap and Self-Replication

A major dynamic in 3D printing is the movement for open source and 3D printer self-replication: what if a 3D printer could create a duplicate of itself? The ‘Replicating Rapid Prototyper’ project, also known as ‘RepRap’, was founded in 2004 by Adrian Bowyer, a former Mechanical Engineering professor at Bath University in the UK, as an attempt to put 3D printing into the hands of everyone at low or at least reasonable cost. Very simply, the RepRap project is an initiative to develop a low-cost 3D printer that can print most of its own components. RepRap printers employ Fused Disposition Modelling (FDM) based 3D printing methods: using a computer-controlled plastic-glue gun and a spool of plastic fed into a heated chamber. The plastic material is squirted out via a small nozzle to make the first layer on a baseplate, which is then lowered by a small amount ready for the second layer, and so on.

According to presentations given by Bowyer, there is a symbiotic relationship between machines and people within the RepRap project: the machines are the flowers that provide goods and people are the insects that will help replicate the machine. While the machine will be able to make all of its plastic parts, RepRap specifies that all the remaining components required for the construction of a duplicate machine, such as the electric motor, electronics assemblies and various other components such as metal threaded rods, must have two properties: they must be relatively cheap and simple to obtain; and they must be easily available to everyone everywhere in the world.

A fundamental motive of RepRap is to make 3D printing available for all and therefore a central tenet of the project is that it must be open source. Anything that can copy itself is subject to the laws of evolution; and because it’s a machine that is manufacturing its own parts, the design files need to be readily available. However, the machine will not evolve primarily by random mutation, it will be much closer a selective breeding process similar to the development of Linux and open source software. Those in the RepRap community will inevitably change the design to improve it, perhaps making it more accurate or easier to build, and naturally many of these improvements will be posted to the web. And if a user has an older RepRap machine, it can be used to make a new machine based on the improved design.

The project has met with much success: there are now a handful of low-cost printers on the market and most of them are based on the RepRap project. In a recent survey on 3D printing (Manufacturing in Motion, Moilanen, J. & Vadén,T), the RepRap project took the largest share of the market. In addition, to further proliferate the concept, RepRapPro, the commercial arm of the RepRap project, was launched in 2011.The first RepRapPro 3D printers available were called Huxley and Mendel, both selling at a cost of a few hundred pounds (sterling) as a kit of parts, with or without the printed plastic components. And now, the next generation RepRap is here – the Ormerod.

The first RepRapPro 3D printers available were called Huxley and Mendel, both selling at a cost of a few hundred pounds.

RepRapPro Ormerod Available at low cost, the new RepRapPro Ormerod complete 3D printing kit is now available from RS. When used in conjunction with the free DesignSpark Mechanical 3D design software, the printer will enable design engineers around the world to develop sophisticated concepts and products incredibly quickly and inexpensively. Also suitable for small production runs, the Ormerod is one of the most versatile 3D printers available: it is easy to expand in functionality, fast to replicate and fast to assemble. Like its predecessors, the Ormerod uses the FDM process, also known as fused filament fabrication, to build 3D objects in a range of plastics and eventually in a variety of colours. This process enables the user to create almost any shape that can be modelled on a computer, including some that cannot be produced by traditional manufacturing techniques at all. While the Ormerod is actually a monochrome 3D printer that has been configured to work with one type of plastic at a time, the device’s head is fundamentally designed to work with three-colour deposition; an upgrade kit is to be made available soon. In addition, the Ormerod’s electronics has been redesigned and now enables connectivity via a web browser. In addition, its construction is far simpler compared to the Mendel, which took two days to put together, on average; whereas the Ormerod only takes two hours, making it significantly more accessible to non-engineers.

The RepRapPro Ormerod is shipped as a kit of parts containing all the required components, ready for assembly. The complete kit includes: all printed parts; all hardware, including threaded and smooth rods, screws, nuts, washers, belts and bearings; pre- soldered and programmed electronics; MicroSD card and adapter; heated PCB build surface; motors; nozzle assembly and extruder drive mechanism; 100m of 1.75mm-diameter PLA (polylactic acid) filament material (approximately 300g); power supply (for EU, UK, US and Australia); and finally, software to run the machine, including firmware for the electronics. Other specifications of the Ormerod include accuracy of 0.1mm, resolution of 0.0125mm, build speed of 1.8mm per minute and deposition rate of 33cm3 per hour.

 

In summary, the availability of low-cost 3D printing technology with the RepRapPro Ormerod in conjunction with the free and intuitive DesignSpark Mechanical and the ModelSource library of 3D component models means that 3D design and rapid prototyping is now available to a much wider universe of users and not just CAD specialists, enabling increased innovation and faster time-to-market.