Change by design
Ian Ellul
Imagination. This represents the bunch of keys with which humankind can attempt to open nature’s locks and unravel its secrets. This being
just a personal point of view – after attending the EuroMold fair in Frankfurt last November – it has now become a justified way of thinking.
Additive manufacturing (including stereolithography) is precisely one of these keys. At this stage please forgo economies of scale being hammered
onto us during management studies and forget as well the scare being instilled in blue chip interim reports that their business positioning will be
negatively affected due to technical migration to poorer counties (namely due to cheap labour). But what is this seemingly tongue twister? To put is
simply it is 3D printing.
In 3D printing a software takes a series of digital slices through a computer-aided design (similarly to a CT scan) and sends descriptions
of those scans to a 3D printer, which adds successive thin layers until a solid object emerges. 3D printers can employ diverse technologies. Objet, an
Israeli company, uses an inkjet head to spray an ultra-thin layer of liquid plastic onto a build tray. The layer is cured by Change by design exposure to ultraviolet light. The tray is then lowered fractionally and the next layer added. Another method is fused-deposition modelling, a system used by Stratasys, a US company.
This involves melting plastic in an extrusion head to deposit a thin filament of material to build the layers. Other systems use powders as
the print medium. The powder can be spread as a thin layer onto the build tray and solidified with a squirt of liquid binder. It can also be melted
into the required pattern with a laser in a process called laser sintering, a technology which EOS, a German firm uses. On the other hand, Arcam,
a Swedish company, fuses the powder in its printers with an electron beam operating in a vacuum.
Indeed, the variations are endless.
And that is why there has been a gradual paradigm shift from simply creating prototypes to producing the finished goods. Actually we are now
seeing machines building parts to build more machines like themselves. Reminiscent of the Terminator movie series, right?
This technology is very versatile and has numerous advantages. One of the most important advantages is that manufacturing objects
through a 3D printer is becoming comparatively cheap to produce, simply because the software which is used can be tweaked endlessly.
Different objects can be produced by the same printer. Remember also that the fixed cost of making a 3D printer, similarly to a normal home
printer, is the same whether you print one object, or thousands of them (excluding maintenance costs, of course). Besides, as opposed
to traditional manufacturing, it is possible to use just enough material to make the finished product thus contributing to considerable weight
savings. Needless to say this drives down the production costs. Also since the number of people involved in the manufacturing decreases this
will push further down the costs. This means that some of the manufacturing would eventually return to the richer countries, this being catalysed by the fact that such technology is handled more efficiently by richer countries since it is they that fund the bulk of the R&D investment.
Where does medicine come into this? The link could not have been more aptly evidenced than by an 83 year old woman who was suffering from
osteomyelitis hailing from Netherlands. Last year a new titanium lower jaw has been fitted in her skull. The link is a 3D printer. An MRI scan was fed
to the printer which in turn made the titanium jaw. A computer controlled high-precision laser was used to fuse titanium powder particles in layers
(it took 33 layers to build just one millimeter). Later, the jaw was coated in a biocompatible ceramic layer. In the end, the jaw weighed 107 grams, which was only one-third heavier than her previous jaw.
Furthermore, replacing the jawbone through artificial implantation took only 4 hours, but if the operation was done in classical micro-surgical
reconstructive method, then it would take 20 hours. As the 3D-printed jaw fitted the patient perfectly, the woman was able to speak and swallow
normally.
And this example is just the tip of the iceberg.