Cutting edge

Stephen Salter. Professor of mechanical engineering, University of Edinburgh

The elite design engineer of the future will need to combine theoretical studies with hands-on experience in the workshop

Inventors suffer from being too early or too late with their ideas. When I was six my father gave me some magnets and told me that they were made by sending electricity through a coil. It seemed very obvious to make electricity by putting a magnet into a coil, but sad that Faraday had done so already. After magnets it was aeroplanes. I wanted to design the successor to the Spitfire and got an apprenticeship as an aircraft fitter. I learned about filing, drilling holes in the right place, wind-tunnels, test-tanks, supersonic fighters, rockets and hovercraft.

I owe my research career to the hostility of a lecturer at the Isle of Wight Technical College, who stopped me getting a university grant. As a result, I was one of the few students who were as poor as many students today and had to moonlight during my degree. This led to a meeting with a prolific inventor, Richard Gregory, who was trying to make a microscope with a scanning objective lens without knowing quite enough about machine tools. Being able to make a round shiny hole of the right diameter in the right place seemed so wonderful to him that I started working more formally on the afternoon of my final exam. Nobody ever asked about the results. By the early 1960s aeroplanes seemed to be less about beating the Luftwaffe and more about dropping atom bombs on Russians, but the chance of getting my own workshop was enough to keep me in a university, working as inventor's mate. After microscopes came a telescope camera, microphones for measuring noises from birds' eggs, robots, a moving-slit spectrograph and a computer touch-screen.

Much engineering involves making things move in the way you want but not in the way you do not. You have to understand actuators, sensors to measure errors, computers to correct them and the bearings where links join. With these skills you can work in almost any area. The greater the number of areas, the better you get because you can import different ways of thinking. Many new products are an intimate mixture of mechanics and electronics, subjects generally separated by tradition and by the jealousies of their respective professional institutions and university departments. Working at the border doubles your range.

In 1973, I started working on wave energy. This needed instrumented models, wave-gauges, test-tanks and a new kind of wave-maker that could absorb reflections. This wave-maker was an invention at the right time and there is now a flourishing industry in Edinburgh. The control idea of the wave-maker may one day be applied to the design of wafer-steppers for making microchips faster, and to improving nanometer precision.

The most rewarding feature has been the experience of a way of educating young designers found by accident during the major model and tank-building projects. If you put bright, motivated school-leavers into workshops and laboratories with skilled engineers and make them use their hands on real projects with good machines and computers, they acquire design skills, theory, three-dimensional thinking and problem-solving ability at an astonishing rate. Furthermore, they understand the need for theory and remember it. The early careers of most great engineers followed this pattern.

But many graduates today, even those with "first-class" degrees, cannot name and do not understand the functions of common cutting tools. They could never make round, shiny holes of the right diameter in the right place and they soon forget much of the theory. My final ambition is to formalise and extend these methods to produce elite design engineers.