How 3D printing is aiding classic car revival

In contrast to INR’s workshop with its ramps, lathes and even a huge five-axis CNC milling machine, Pugh’s place is a high-tech oasis of calm. In one corner is a 3D printer, methodically layering up, in plastic, a bevel box for a pre-war, chain-driven Frazer Nash. Once completed, it will form the pattern for a sand cast moulding in metal. As it quietly goes about its business, Pugh draws my attention to the room’s other occupant: a 3D laser scanner. Looking like an angle-poise lamp but with a probe at the end rather than a bulb, it’s fixed to a sturdy metal table and connected to a laptop.

Pugh’s colleague, Alberto, shows how, by painstakingly moving the probe around a component – in this case, the diff casing from a 1952 Alta GP car – he can capture and digitise its every dimension, including the internal faces of the screw bores. The result is an accurate digital representation that can be converted into a CAD file for a 3D printer or into an engineering drawing for a machine shop to follow.

“‘From gaskets to gearboxes: scan it, draw it, make it’, we like to say,” explains Pugh. “Laser scanning and 3D printing have so many uses, from enabling classic car owners to have a digitised record of their car from which body panels, for example, can be recreated after a crash, to producing replica parts in plastic as a pattern for a sand cast or simply to test fit and function.”

On that point, he takes the other half of the Alta’s diff casing, produced earlier in plastic by the 3D printer, and inside it places the original crown wheel and pinion, and limited-slip differential so I can see how they fit snugly into their respective places.

But should it all look like just moving a probe and clicking a mouse, Pugh is quick to point out that interpreting the data and knowing what is possible from a manufacturing perspective are crucial. The former graduate engineer speaks from experience, having started out spannering for Nuthall before moving into contract work with Ford, Aston Martin and Jaguar. In fact, it was Nuthall who lent Pugh the £125,000 necessary to buy his first scanner.

He’s now on his fourth and, using it in conjunction with his 3D printer, Pugh has produced a huge variety of components, including a modified and strengthened sump with anti-surge baffles for a Renault 5 Turbo, a bell housing and diff casing for a Volvo 242 GT and even door handles for an E30-era BMW M3. However, one of his proudest achievements is producing a digitised version of a very rare pre-war coupé – with only a saloon version and photographs to go on.

He says: “With no existing model available, we had to scan the saloon’s chassis, steering wheel, back axle and engine to establish the coupé’s hard points and the locations of its major mechanicals. Then we placed a scale archive image of the coupé behind the resulting CAD drawing as a guide to the body’s angles and curves. This part was all done by eye. Having established the body’s shape, we created a one-eighth-scale buck in the 3D printer. This we used to give us the dimensions for the car’s ash body frame.”

And here before me in the workshop is that partly assembled frame in actual size, looking for all the world like a particularly complicated piece of self-assembly furniture. It’s an inspiring story of how a long-lost car has been brought back to life by modern technology. But as I make my way out of Pugh’s high-tech workspace and past the assorted historic road and race cars in INR’s workshop, it’s obvious that it’s not the only example of modern technology coming to the rescue of old and not so old motors.