KEY POINTS:
Few of us don't have access to a laser or inkjet printer for outputting high-quality text and images. The day is coming, according to an AUT University professor, when 3D printers will be just as widely available and will allow us to produce customised items of all kinds - a toothbrush, a crown for a tooth, a house or even a kidney.
That's the world described by Olaf Diegel last week in his inaugural professorial address, marking his appointment as professor of product development at AUT. Diegel heads the university's Creative Industries Research Institute, in which postgraduate students are working on different aspects of 3D printing.
Rather than pushing the envelope, you might say they're helping to refine its form. The 3D printing process works by layering thin slices of plastic or metal - and even biological material - and fusing them in a precise shape.
Typically, objects are built from flat layers and as new ones are deposited on top of each other, they leave a stepped edge. One of Diegel's students is developing a way of making curved layers, to produce a smoother edge and stronger laminate.
"Imagine you're printing a hemisphere, or half ball. We want to be able to print it by having the layers follow the round surface," Diegel says. "We've managed to get our first proof of concept to show that it does work so we'll be able to print parts that don't have the staircase effect and don't have the weakness in the lamination."
Technology for 3D printing has developed from rapid prototyping used for years in product design. It starts with creation of an object using computer-aided design (CAD) software.
That's then saved as a stereolithographic (.stl) file, which is sent to the rapid prototyper, or 3D printer, in the same way as a word processing file. The process, says Diegel, gets products to market faster, cutting development time by as much as 50 per cent. It also leads to improved design.
"From a product development point of view, no company in New Zealand, or anywhere, would put something into the market without first doing a rapid prototype, a 3D print."
Diegel recalls developing a blood pressure monitor designed, with patients in mind, to be as unobtrusive as possible. However, once doctors got their hands on his prototype, they told him they actually wanted something big and flashy for the device's $3000 price tag.
By going back to the drawing board at that stage, he saved a six-figure amount on tooling for production of the device.
Prototyping machines are fast becoming cheaper. A $30,000 machine which AUT has would have been 10 times as expensive just a few years ago. They're also becoming much more capable.
"The current state of the technology has gone way beyond plastic parts. We can now do metal - titanium and stainless steel."
That's by a process called laser sintering, used by the French military, Diegel says. "They actually design a part, hit the print button and bolt it straight on to their fighter jets.
"To me the biggest change is that it's no longer prototyping, it's becoming manufacturing. Now this technology can actually make real products for use in everyday life."
The possibilities are boundless. Warehouses of spares will disappear as replacement parts are printed on demand.
That won't just be confined to inanimate objects. Already, hip joints are being produced to individual requirements and a hearing-aid manufacturer is making devices tailored to the shape of the wearer's ear canal.
On a bigger scale, a University of Southern California researcher is developing a machine that, by layering concrete or other materials, will construct a house directly from an architect's CAD drawings.
Diegel says much research effort is going into developing new materials, including those that can be implanted in the body.
"There are a lot of papers out there about people printing body parts - that's miles away yet, but that's the ultimate goal." Printing a kidney may not be possible in his lifetime but he thinks less complicated parts will be available.
Within a couple of decades, homes will have their own 3D printers, he predicts. Then, if you need a new toothbrush, you'll feed in the old one, it'll be broken down, recycled and a new one will pop out with bristle hardness, colour and grip customised to suit you.
"It's borderline science fiction but it's not science fiction that's 50 or 100 years away. It's science fiction that's five, 10 or 20 years away, which is what makes it fairly exciting."
THE ADDED DIMENSION
* 3D printers take a computer design file and turn it into a solid shape.
* Many work like an inkjet printer, building up successive layers of some material - anything from corn starch, to plastic powders, to molten materials.
* Often used to create prototypes.
* Increasingly used for manufacturing finished products.
* Have been suggested as a way of making replacement body parts out of layers of living cells.
Anthony Doesburg is an Auckland technology journalist
