Digital technology has and continues to transform nearly every aspect of our lives, from ordering shopping and planning journeys through to everyday communications and online banking. The introduction of digital technologies into our design and manufacturing sectors has not just moved the goal posts, but it’s cut them down and burnt them. With the introduction of CNC machining capabilities, highly accurate and often intricate parts could be digitally designed in three-dimensional CAD packages, then quickly and consistently manufactured over and over again.
In applying this technique to the design and rapid production of moulds for injection moulding, designers and engineers could quickly turn their ideas into real prototypes and when companies such as Proto Labs brought these technologies together with highly advanced proprietary software to automate and speed-up the process even further, the era of rapid prototyping and production was born.
This capability has meant that, in an ever-more demanding global market place, companies can see their products evolve much faster than before and with lower capital investment being required – responding to changing customer demands and often extending a product’s life. With the ability to prototype using real-life components, design issues can be ironed out and products launched quickly, enabling companies to stay one step ahead of their competitors.
Product development can now be much more innovative than in previous decades, with all components designed, tested and well proven ahead of launch. This of course puts a lot of pressure on the prototyping process, but with the recent advances and automation mentioned earlier, the technology is more than capable of meeting these needs.
Up until relatively recently, the main choices for rapid prototyping have been confined to CNC machining and moulding techniques. With the advent of additive manufacturing - or 3D printing to use its more common name – the opportunities for prototyping and low-volume production of parts with incredibly complex geometries has arrived. Although these systems have been around for a few decades, their capabilities have reached the point at which they are not only accurate enough, but also cost effective to be used as a front-line technology.
Laying down micro-fine layers of material such as plastics or metals, intricate components can be created by additive manufacturing, including features that would otherwise be impossible to machine or mould. The capabilities of the various methods available have come on in leaps and bounds, with one of the most accurate systems, stereolithography additive (SLA), being able to work to layers of around 50 micron (0.05mm) thick - which is a fraction of the thickness of a human hair.
With such a fine resolution, technologies such as SLA can also produce very smooth surface finishes, meaning that minimal finishing is required for most components.Typically, material choices for Proto Labs’ SLA system have a similarity to Polypropylene or ABS providing a wide range of characteristics for the prototyping process and the ability to add additional finishes to meet the needs of the product’s required aesthetic qualities.
This highly-accurate method is vastly superior to the commonly found fused depository modelling (FDM) systems that are widely used by hobbyists. In comparison, the entry-level FDM systems typically have a layer thickness of 127 micron (0.127 mm) compared to the micro-fine resolution of SLA that can produce parts with an layer thickness of 50 micron.
Smart Prototyping
Smart prototyping, as it has been coined, is now using additive manufacturing techniques to produce the very first prototype components. Importantly, they can use materials such as plastics and metals to closely match the mechanical properties and appearance required in the production components, meaning that are identical (or very close) to the real thing. Being able to produce small quantities of such components quickly and very cost-effectively is revolutionising the product development process.
With their 3D CAD models at the ready, designers and engineers can quickly create virtual assemblies of their components for further evaluation and testing.
Once satisfied that they are on the right track, the data from individual parts can be uploaded into the automated systems such as that offered by Proto Labs, where high-powered arrays of computers analyse the data and determine its suitability for manufacture, produce an almost instantaneous quotation – breaking down the design layer-by-layer to provide the set of instruction for the SLA machines to work from.
If it’s a product destined for mass production, then the smart prototyping route will enable designers and engineers to extensively test their product before taking the next steps towards creating full production moulds. Quite often, initial low-volume production runs can be produced by additive manufacturing, or in the case of different materials being needed, rapid-turn moulding services can be used as a short-term bridge (up to 10,000 units) before the transition to high-volume production runs is required.
Once introduced into the market place, customer feedback may well necessitate further design iterations, making the use of additive manufacturing techniques a vital tool in the earliest stages of a product’s life.
Manufacturing the Impossible
As alluded to earlier, additive manufacturing techniques can create intricately complex geometries that would often be impossible to mould, including features such as internal channels and holes that would be unreachable by end mills, or entire assemblies printed as one single piece.
One consideration when designing parts that will be produced with additive manufacturing is that many of the normal considerations for moulded components no longer apply. Aspects of the design such as draft, radii and uniform wall thickness are not as critical, but, should the production method eventually transition to injection moulding, then design changes may well be required.
Production
As with rapid-turn moulding services, additive manufacturing techniques such as SLA can prove to be surprisingly cost effective and delay or even fully negate the need for production tooling.
In applications where heavy use of customisation is prevalent – such as medical and dental – additive techniques are streets ahead of all other techniques. With the shift towards higher levels of consumer choice and the ability to customise products, additive techniques are going to play an ever-increasing role.
When looking at mass-produced consumer goods, then traditional machining and moulding techniques will continue to have the edge, but the use of additive will help lower the costs of development and speed up route to market.
Choosing Suppliers
When selecting a rapid prototyping or low-volume production partner, anyone anyone can claim to be the fastest, but what’s important is to be the most consistently fast, whilst also being able to maintain the very highest level of quality.
At Proto Labs, we not only have an advanced and fully-automated process controlling the various manufacturing technologies of additive, machining and moulding – but a team of experienced engineers that are at hand to ensure that customers are helped at every stage.If their proposed design is not suitable for the chosen manufacturing technique, quite often, Proto Labs’ engineers will have already created adjustments to the design and sent them back to the client for consideration, along with a detailed quotation within hours.
To find out more about how additive manufacturing can revolutionise the prototyping process, please contact Proto Labs on +44(0)1952 683 047 or visit www.protolabs.co.uk where there are a selection of white papers and additional design resources available for free download.
