Time to bring 3D printing in-house?

The buzz around 3D printing continues unabated. So is it now at the stage when that sweet spot between price and capability has been reached, and no self-respecting design team should be without one?

3D printing gets masses of media coverage and there is a reason for that. People see the potential. In our recent survey of Eureka readers over half the respondents quoted 3D printing as the single most disruptive technology affecting our industry. But is the reality matching up to the hype – at least to the point where it should be a standard rather than a luxury appliance in a design environment? We asked one 3D printer supplier, a design consultancy and a prototyping house for their differing perspectives.

But before installing a 3D printer as a standard accessory, perhaps the first question that needs to be addressed is what do you want your 3D printer to make for you? Ross Nicholls, general manager of prototyping company Malcolm Nicholls, commented: "The answer to this question is what is most commonly misunderstood by the masses. The idea that we can print anything that you can imagine is not uncommon. Managing expectation is a very important part of project managing our work. Believe it or not, we have actually been asked if we could produce a small scale motorbike engine that actually worked, all for less than a tank full of petrol in cost!"

With respect to mass production, could 3D printing replace injection moulding? "Certainly not now," claimed Nicholls, "and not in the next few years. Will it ever? – maybe."

Assuming then that we are not looking to 3D printing for next generation manufacturing, but as the 'turn to' prototyping solution, is the quality of 3D printers now adequate? Again that depends on the particular application. "For a lot of parts and models, the level of detail and resolution that current generation printers produce is excellent," said Fred Hamlin, a principal engineer at product design and development firm Cambridge Consultants. "However, if your part contains very small details, or relies on parts which are expected to slide past each other or tight tolerances on parts which have to fit into each other, then printed parts often are either not suitable or will have to have additional subtractive manufacturing operations performed on them afterwards. The surface finish of 3D printed parts is often quite different from the equivalent moulded part you are trying to simulate."

This is often not an issue but must be a consideration, as is the lifetime of the part. Usually the longevity of a prototype is not important but if it is then the degradation of some of the polymers used in 3D printing must be taken into account.

And, if calculating total cost of ownership, these polymers remain expensive. Nicholls commented: "SLA materials are circa £150 per kilo, still very expensive, these prices haven't changed much for years. SLS material can account for 50% of SLS component prices, again the price hasn't really changed much over the last 5-10 years. Filament for FDM type machines is decreasing with increasing competition."

Part of the reason for lack of movement on prices is that the market has not developed enough for economies of scale to apply, according to Peter Hansford vice president of sales at 3D printer manufacturer Blueprinter. "The big chemical companies are not directly supplying and they won't get involved until the market is big enough. For them 3D printing is very small. Higher prices of materials leads to lack of use, which is counter-productive for end users. There does need to be a balance, I see the pricing coming down in most cases for the future. If you buy a printer today that costs a lot to run, you might not have the money to invest in additional technologies, so choosing the right type of 3D printer is very important."

Getting an early prototype in hand can be invaluable when trying to sell a concept - either internally or externally

Blueprinter now believes that 3D printers have come down in price sufficiently to become affordable for the masses and claims there are ROI calculations to prove it. Moreover, claimed Hansford, it has allowed users to benefit in unexpected ways. "It can change the way they create products," he said, "changes the way they work. So buying the correct equipment is the key regardless of initial cost, as long as the payback is there."

The payback depends on what needs to be made and how often. A high-quality professional FDM (fused deposition modelling) machine, which would be suitable for handling models and industrial design rapid exploration of form factors, would require no larger an investment than many of the software packages or IT infrastructure which most companies already own.The problem is that one 3D printer does not do everything. Companies like Cambridge Consultants require a range of materials, sizes, finishes etc. Hamlin said: "The major hurdle is that many companies, ourselves included, require flexibility in the materials and construction technology they are able to use so that they can select the correct properties for the part. This requires a whole room full of state-of-the-art machinery rather than a single installation. This rapidly multiplies the capital expenditure and associated maintenance costs, which become prohibitive."

This is one of the reasons why bureaus/prototyping houses remain popular. Another is that bureaus will invest in the latest technology so that its customers don't have to. They also, as Nicholls (predictably) pointed out, believe they offer the best value for money: "I firmly believe this is still true today as it has always been. We have lots of technologies to chose from to best suit the application in mind. We also have highly skilled finishers to produce the quality demanded. The market place is still full of potential service providers so competition is rife ensuring that prices are kept competitive."

"In my opinion they do offer better value for money," concurred Hamlin. "Using external services means that you are not tied to one technology or resin and can easily pick and choose what materials you want the part to be constructed from, depending on the aesthetic, mechanical, tribological, dimensional and cost requirements of the part."

And while Hansford does not disagree with this, he added: "3D Printers can be bought for small amounts - sub £10K - and it's all about sharing ideas and communication. There is a huge advantage of having a printer to explore a design brief or going off piste with something a client hadn't thought of. It helps all aspects of the business - design, engineering, marketing, packaging, customer steering groups etc. Showing parts in someone's hand has a huge impact."

Perhaps that sweet spot is still a few years off. While machines are affordable for all, the ones that provide the necessary quality are typically found in the bureaus. But maybe the machines at the lower end of the market are increasingly being deployed by design teams for those 'first design in hand' scenarios.