Paul Woodward
1st July 2016 at 15:56

Subject Genius, Paul Woodward, BAD CAD DAM CAM

No, that’s not an onomatopoeia suggesting an oversized D&T project collapsing, but the briefest summary of how I have seen and heard CAD and CAM described over the years. Here are two technologies that have revolutionised industry and the D&T classroom, yet they aren’t always welcome additions to the subject for one reason or another.

Computer Aided Design is technically any design work which is aided by a computer, so effectively that means anything and everything from Microsoft Paint to the AutoCAD suite of industry standard software. Of course, we tend to think of CAD as 2D and 3D with the former used for image creation and manipulation while 3D CAD, once simply about creating the appearance of a 3D object on screen, is now much more closely linked with CAM.

We all know the generic advantages of CAD that can be used to answer that question that pop up in D&T exams every other year. Virtual storage of thousands of models, photorealistic rendering, ability to change materials and colours, sharing files etc. but most of these apply equally to some extent to Power Point documents. Where CAD really excels is in visualising products or concepts, ‘pre-testing’ ideas and structures before costly manufacture begins and, increasingly as a means of communicating with machinery to create manufactured objects. The danger with CAD as a creative tool is that you can create just about anything you can imagine…but not always recreate it in the real world. To paraphrase Harrison Ford’s response to George Lucas while filming Star Wars: “You can type this s**t but you can’t say it!” I have lost count of how many times I have seen students invert 3D objects in SketchUp to make some mindboggling mess of polygons which they think are actually cool only to then ask ‘Can I make this now Sir?’

Sadly, CAD used as an alternative to pen and paper simply because it’s available or it’s ‘in the assessment criteria for a higher mark’ can be a dangerous approach. Not only is there the potential to veer off task when on a computer (Google, You Tube, Facebook etc.) but there is the danger that the virtual world simply doesn’t reflect what is possible to manufacture in the real world in any software but the most advanced CAD packages which are often way beyond the abilities of many students. Additionally creativity may be limited to the shapes that can be constructed within the software or the limits of the interface rather than the student’s imagination. Strange that such a dichotomy should exist between limitless (read; practical) creative freedom and being restricted by the software or interface, but technology can often work against you.

That brings us on to Computer Aided Manufacture or CAM; the acronym that applies to machines connected to computers that can make objects or perform a physical process and this can range from vinyl cutters to 3D printers. It is another technology that is often used for its own sake rather than for the benefits it can bring, but many of those have been discussed previously. CAM, much like CAD revolutionised the way designers design and changed the way manufacturers ahem, manufacture. In a consumer driven society the speedy supply of cheap mass produced items is necessary to satiate the needs of the consumer but there are many areas of design that can specifically benefit from the use of CAM.

Rapid prototyping of ideas in order to ascertain their suitability and progress the development of a product is an invaluable tool in the designer’s arsenal. 3D printing, as discussed previously is unrivalled in allowing for objects to be constructed or structured in ways never before possible. Equally, the ability to produce a wide range of identical components with incredible accuracy is vital in developing mechanical and engineering concepts or even to produce a batch of items to test or for commercial purposes…but cutting out a few squares in acrylic?

As you can see, my gripe is not with the technology or even their practical use in the classroom it is simply when CAD or CAM are used because they are there and need to justify their investment or to demonstrate a process that could just as easily be shown by video and be more effective at no cost. It is also the production of sub standard designs or physical products because they are the product of using CAD or CAM badly when another approach would have been more beneficial. Surely the key to teaching design students is that old adage ‘the right tool for the job’ rather than ‘technology is here to stay so you might as well get used to using it’.

We would all agree that here are two technologies that have pretty much revolutionised the way we approach the design and manufacture of products, but stop for a second  and ask if they are actually improving the quality of what we teach and how students learn about the process. There is no doubt they are important learning tools and should be studied in use but are you really using them to their full potential or simply because you need to justify the cost or to keep the subject ‘cool’ and appealing to the kids. Do they really enhance the work or open up a world of commercial or entrepreneurial possibilities? If not, why on earth would you feel compelled to use them?


Paul has taught design and technology for 23 years in a range of schools with stints as HOD and Head of a Creative Arts Faculty. He is currently taking a short break from DT to teach photography and media studies.

His Subject Genius blog was shortlisted for the 2016 TES Awards.