How to knit a sports car with carbon fibre

BERTHA RESIDES on a quiet industrial estate in Bristol, in the west of Britain. The affectionate name has been given to what at first appears to be a giant loom from the Industrial Revolution. And in some ways it is. Bertha (pictured above) is an automated braiding machine. Like a horizontal maypole, ribbons of carbon fibre are drawn from 288 bobbins contained on a pair of huge rings, and passed over and under one another as they are wound tightly around a revolving mould. The final product could be a propeller for an aeroplane, a ship’s hydrofoil or a set of wheels for a sports car. In fact, Bertha can knit just about any hollow component up to 800mm by ten metres, and do so quickly and accurately by depositing some 300kg of carbon fibre an hour.

Just as textile production began to be mechanised at the end of the 18th century, creating the modern factory, manufacturing is going through another revolution. This time it is driven by digital processes and new materials, such as carbon-fibre composites. Automated braiders are one of several new systems turning carbon-fibre production from a slow, labour-intensive craft into a mass-manufacturing process that will change many industries.

Carbon fibre is attractive because it is lightweight and exceptionally strong. The toughest fibres are up to ten times stronger than steel...