RepRap 3D Printing Movement

A Self-Replicating Design for Rapid Prototyping and Inspiring Innovation

By Mark Cundle, Head of Technical Marketing at RS Components

Three-dimensional (3D) printing can create quick-turn-around prototypes and save months in the design cycle. While the 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, the RepRap open-source self-replicating 3D printer initiative, in conjunction with the free-to-download DesignSpark Mechanical 3D modeling software, is presenting companies and developers with an opportunity to shorten the product development process and inspire innovation.

 

3D Printing

3D printing is revolutionising product development. It is the process of making a solid object from a 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. 3D printing is increasingly being used for rapid prototyping and also some manufacturing across many industries including engineering, construction, automotive, defence and aerospace, medical applications and a number of consumer industries. Increasingly, it is moving from a niche technology used by larger companies into a mass market for consumers and small businesses, and 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 manufacturing approach of old.

 

Rapid Prototyping – Hours Not Weeks

While 3D printing is making an impact in mainstream product manufacturing in many industries, especially in low-volume or highly customised applications, the technology has its limitations for high-volume production. However, the ability to build prototypes rapidly is revolutionising product development as 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.

 

RepRap and Self-Replication

A major dynamic in 3D printing is the movement for open source and 3D printer self-replication. 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, and is an initiative to develop a low-cost 3D printer that can print most of its own components. RepRap printers employ Fused Filament Fabrication (FFF) based 3D printing methods. It uses 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.

While the machine is 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. In addition, 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, i.e. the design files need to be readily available. 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; therefore if a user has an older RepRap machine, this can be used to make a new machine based on the improved design.

 

RepRapPro Ormerod

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. The latest RepRapPro design, the Ormerod complete 3D printing kit is now available. When used in conjunction with 3D design software, such as the free DesignSpark Mechanical 3D tool from RS, 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.

Figure 1 – RepRapPro Ormerod

Like its predecessors, the Ormerod uses the FFF (Fused Filament Fabrication) process to build 3D objects in a range of plastics and 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 a monochrome 3D printer that has been configured to work with one type of plastic at a time, the device 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 its immediate predecessor, the Mendel, which took two days to put together, on average; whereas the Ormerod takes considerably less time, making it significantly more accessible to non-engineers.

 

Kit of Parts

The RepRapPro Ormerod from RS is being shipped as a kit of parts containing all the required components, ready for assembly. The complete kit includes: all 3D 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); 220V power supply (for EU, UK,  and Australia); and finally, software to run the machine, including firmware for the electronics. Other specifications of the Ormerod include build volume of 200 x 200 x 200mm, accuracy of 0.1mm, resolution of 0.0125mm, build speed of 1800mm per minute and deposition rate of 33cm3 per hour.

In addition, as all RepRapPro printers are capable of self-replicating their own plastic components, hardware-only Ormerod kits without 3D-printed plastic parts will also be available, meaning that Ormerod owners will be able to make Ormerod printers for others. The availability of low-cost 3D printing technology with the RepRapPro Ormerod, in conjunction with design software such as the free and intuitive DesignSpark Mechanical and an extensive library of 3D component models from RS, 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.

The RepRapPro Ormerod is available via the RS website at /web/p/3d-printers/7952333/ and DesignSpark Mechanical is available for free download via the DesignSpark website at www.designspark.com.