3D printing – revolution, evolution or hype?

Is there anyone left out there who has not heard of 3D printing?  According to analysts, over the next four years the 3D printing industry will be worth over $10 billion and more than 2 million 3D printers are expected to be sold around the world by 2018.  We’re now expecting our cars to come with 3-D printed components, we’ll all have a 3D printer in our homes, there’s the recently launched Pi-Top 3D printed laptop kits and we’ll even be printing habitable environments on Mars.  Some have gone so far as to argue that 3D printing will transform supply chains; it’s not goods we’ll be moving around the world but data driven to  local printers.  Not quite the tele-transportation of Star Trek fame but not far off – ‘Beam Me Up Scotty’.

Back to where it all started ..

There are many techniques for 3D printing.  Almost all rely on the principle of creating a 3-D object by building it up layer by layer.  The simplest, plastic machines extrude molten plastic from a print head as it passes over the previous layer.  The most common technique for metals is to lay down layers of powdered metal and use lasers or electron beams to melt the powder wherever solidity is required, layer by layer.  Despite 30 years of development the machines are still slow and, in the case of metals, expensive. However, although slow in actual print time there is virtually no setup time.  Conventional manufacturing may need special tooling such as press tools or casting moulds which is  time consuming and expensive. So 3D printing has found its niche in producing prototypes cheaper and faster than by conventional means.

Investment in faster technology

The reason we do not have faster machines is that no one is yet prepared to invest in designing and making them.  Most of the companies who make 3D printers are relatively small and cannot afford the considerable investment needed. The Logistics Business is involved in a number of projects funded by the government’s, Innovate UK initiative to transform 3D printing into a volume production process and to make the UK a leader in the field.

And there are other good reasons we want to do this….

3D printing has a trick up its sleeve.

Because a component is built up layer by layer and because there are no tooling restrictions, such as the need to be able to get the piece out of the mould, internal and other features can be manufactured that would not be possible using conventional methods. In some cases this makes it possible to create a hollow component, where conventional manufacturing could only make a solid one, saving weight and material.  It’s also possible to make something in one piece that would otherwise be made up of many components e.g. an aircraft engine manufacturer is soon to start manufacturing a fuel injector in one piece that previously comprised over 20 components manufactured separately and then assembled together.

And what about the impact on supply chains?

It’s certainly true that if someone did suddenly produce a machine capable of volume manufacture the rest of the supply chain would be unable to cope.  This is particularly the case with metals.  There are only a small number of companies capable of manufacturing the powders and the range of alloys available in powder form is much smaller than in other formats.  And then there is the reverse supply chain.  Only a small percentage of the powder gets solidified in a typical manufacturing cycle.  The rest has to be removed and either re-used or re-cycled but no one really knows how many times the powder can be re-used before it becomes too contaminated or its properties altered in some way and the reverse supply chains needed to process this barely exist.  Similarly 3D manufactured components usually require a range of finishing processes which may not be available in the quantities required.

But the biggest barrier to becoming a volume process probably lies in the heads of designers.  To really make 3D printing a success designers must find new ways to exploit its capabilities, particularly those where conventional techniques cannot compete.  That means designers have to think about design in new ways and in a very real sense be able to think in 3D.

So what is the future for 3D printing?

Will it ever replace conventional processes or is it destined to remain something between a novelty and a prototype / small batch process and will 3D printers become ubiquitous in the home in the way that paper printers have?  Of course no one really knows.  It is almost certain that the use of 3D printing will increase and will become a volume process for those components and products that cannot be manufactured using conventional techniques (which of course are themselves improving all the time) but probably not for those that can.  Printers in the home are unlikely to be much more than a novelty for most but may become part of the DIYer’s tool kit.  And yes, there may well be 3D printers on Mars but that’s unlikely to be troubling the supply chains that we work in, in our lifetime.