Dear Colleagues

Imagine scanning a broken part that is no longer available (for your vintage car) into your computer and then printing out (in 3-dimensions) a replacement in plastic in 60 minutes. A few further adjustments and then you print out the finished version (which you may also give to a machinist to make a metal copy of). This is what is happening today throughout the world – a good example being Mr Jay Leno (the well known hated and loved celebrity) who has his own 3-d printing machine to keep his fleet of old cars on the road (in this case a 1907 White steam-driven car).

These new 3-d printing technologies will undoubtedly have an enormous impact on your work as an engineering professional. Whether you are a plumber fashioning out a difficult to find part or an aerospace engineer creating the aerodynamic ducting on a jet fighter, so it is worth finding out more below..…

Some basic 3-d printing details

Some other terms used are ‘additive’ (and ‘subtractive’) manufacturing. Or simply, ‘3-d printing’. Some of these printers are small enough to fit on your desktop and are appearing everywhere from the consumer/hobbyist to the large sophisticated manufacturing facilities ranging in price from $10,000 (where laser printers were many years ago) to millions of dollars. Printing takes typically an hour for a small simple object with accuracies (at present) of slightly under 0.1mm. The market size was $1.2billion in 2008 and this is estimated to double by 2015. Model making and rapid prototyping are the key uses at present.

One would have thought that with all the incredible 3-d visualisation software available on computers that this would be the key approach; but people simply love to physically hold an object in their hands before commencing a major manufacturing investment. And 3-d printing makes economic sense – Timberland used to take a week to turn out a model at a cost of $1200; now they do it with 3-d printing (from Z-Corporation) in just over an hour at a cost of $35.

It works – layer by layer…

There are a variety of different approaches to 3-d printing. But the first stage is to take cross sections through the part that you want to create and to let the software compute how each layer needs to be constructed.

The traditional approach has then been to squirt a thin layer of liquid resin (plastic?) onto a bed and in using an ultraviolet laser to make it harden to the required pattern. The build tray then descends and a new liquid surface is applied to this layer and the process is repeated.

Another approach followed by Z Corporation is to use a modified form of inkjet printing and to squirt a liquid binder onto a bed of white powder where the layer needs to be solid. Colour is also applied, allowing multicoloured products to be developed. The bed is then lowered a tiny amount and a new layer of powder is spread on top. The next layer of liquid binder is squirted onto this and the process is repeated.

A third approach (from Stratasys) is to feed thermoplastic material from a spool through a moving extrusion nozzle, heating it and then laying it out in the required pattern on a tray.

What are people doing with this technology ?

In addition to ones noted above, there is an incredible range of products being created with this impressive technology. From creating models of video characters to products in consumer electronics, aerospace and car manufacturing. Extending to artists and design studios. Firms are setting up to create products cheaply and effectively and shipping them all over the world. Your local printing store may just be about to install a 3-d printer to offer this service. And naturally, watch out for new tiny digital fabrication stores appearing in your street. The open source RepRap Project based at the University of Bath in the UK, has produced designs for a printer which can be built for $700; with thousands of printers already being built around this design.

How can you seize the moment here ?

This new technology is going to touch all engineering professionals and it is worthwhile finding out more.

• Read up on the topic and think how you can apply it to your work and applications
• Consider how you can cut costs and improve output and quality using this technology
• Consider the commercial prospects in purchasing your own machine
• Do some lateral thinking of where you can apply 3-d printing in unusual ways

In attempting these new technologies – as Robert Rodriguez says:

Only by seeking challenges can we hope to find the best in ourselves.

Thanks to the Economist, the RepRap Project, MIT and Z-corporation for some interesting reading.

Yours in engineering learning