THE PROTOTYPE SHOP
Finding out how dreams are made real
Coventry. Cradle of the British motor industry, birthplace of many a manufacturer. Home to myriad engineering shops. Home, too, to myriad metal-bashers, although that dismissive term does no justice to the shapers of handmade panels that supplied not only our coachbuilders, but also the major manufacturers as they developed prototypes of new models.
Their names ring loud in the industry’s history: Park Sheet Metal, Motor Panels, Coventry Radiator and Presswork, Carbodies, Coventry Prototype Panels, Abbey Panels and more. It was firms such as these that built bodies for competition and low-volume sports cars, including – to use Abbey Panels and Jaguar as an example – the XK120 and its C-type racing derivative, the D-type and its XKSS derivative, the XJ13 and, right at the end, the XJ220. Abbey made bonnets for the E-type, too.
But that’s all in the past. The motor industry has changed, Coventry has no more car plants and those skills aren’t needed in the modern world. Or are they?
You see a concept car at a motor show. Who built it? Probably not its manufacturer. The work, the making-real of the sketches and the renderings, is most likely subcontracted to a specialist body-creation and prototyping company. Italy still has several of these, producing fabulous concept cars for many big-name manufacturers. With all that carrozzeria history, you’d expect Italy to be good at that. But Britain is good at that too. A new Bentley or something from Jaguar Land Rover, a proposed Nissan, something for new magnate Geely – and dozens of others – are among the in-themetal realisations of the Envisage Group, a collection of companies flourishing across seven Coventry sites.
Envisage can also build production prototypes and develop the data to make the tools required for full production. It can design a car from scratch. It can hand-build bodies for specialist companies, and finish the complete car if required. From potential multi-million seller to bespoke one-off, Envisage makes its creation possible.
Bodies for the continuation XKSS? No problem. Reverse-engineer a body buck for the Bensport project by scanning the single prototype, so more bodies can be made to higher quality? Of course. Or maybe build new bodies for a short run of replicas or evocations, perhaps using nothing more than photographs as the starting point? Envisage can do that too.
One recent, much-publicised Envisage project was to build the prototype of the Jaguar XKR-based DB Speedback. That was when many people heard about Envisage for the first time; one of the paradoxes for a company like this is that it wants the world to know what it does while its customers generally insist on secrecy. David Brown’s outfit, however, was keen to celebrate the huge but little-known expertise on offer in the heart of England, and did Envisage a favour in the process.
Since then, Envisage has been able to disclose involvement with a high-profile project in the world inhabited by Octane. Jaguar didn’t allow this initially when revealing the ‘continuation’ XKSS project but, after the Channel 4 documentary on the subject was aired, Envisage could show how it was building the bodies and mating them to the engine cradle.
Around 12 of Envisage’s craftsmen in its Quinn Close facility, the nexus of handmade metalwork, used to work at Abbey Panels. In some cases their fathers and grandfathers worked there too. And so the circle is closed.
WHERE TO START in an attempt to take in what Envisage does? On Octane’s visit we begin with how the company helps a carmaker get started with a new model. Some of the processes apply to the retro and bespoke projects too, as we’ll see.
So we’re at Visioneering – originally a separate company – in Herald Way: build studios, machining, model-making and, crucially, tooling. ‘This is the typical craftsmanship process,’ says production director Dave Rouse. ‘Once we have the design in Alias software, we make a 3D hard model. It’s in clay, so the designer can tweak
it if needed and refine the surfaces. We’ll then scan the model, just one half, which is mirrored for the other side to make sure they’re the same. The scan is compared with the “package box” – all the required dimensions for the finished vehicle – to make sure it all fits. Then we make the “Feasibility Cube” or Surface Reference Model.’
This SRM is machined in manageable sections, by computer-controlled cutters, from blocks of polyurethane tooling board. Glued together, these represent the surface data and the ‘first radius’ of any panel edges – the bits you see on the finished car, in other words, but nothing beyond. This is then despatched to the engineering department, which will devise a viable and manufacturable structure. ‘That,’ says Rouse, ‘is when the money really starts to be spent.’
Now comes the ‘Function Cube’ or Data Control Model. This includes all the panel returns, the door inners, the undersides of bonnet and boot, but all of it as seen in the completed structure rather than in the individual metal sheets that comprise it. At this point any fitment and alignment issues can be fixed before making the ‘Environmental Cube’. This is machined out of aluminium billets totalling 25 tonnes, again in manageable sections.
Sixteen weeks later there’s a full set of body sections weighing maybe four or five tonnes. The rest of it has been reduced to vast quantities of swarf, all of which is recycled.
One piece might represent, for example, a hollow box section complete with outer skin folded over inner, but it will be one solid machining. They are all bolted together on an armature of extraordinary precision and accuracy, to make a full-size representation of the final car’s shell. This is measured to create a reference for the body press tooling in a temperature-controlled room. Now is the last chance for final adjustments.
That’s for an all-new car, and we sneak a look at a work in progress in the machining shop where aluminium blocks are nibbled away, one side then the other in a coarse cut, then back to the first side for the next, finer cut and so on – all to minimise stresses and dimensional distortion. So how is this relevant to an XKSS body, or the Bensport project in which a curvy coupé body in an early-1950s style is created from scratch to mount on a Bentley R-Type chassis?
The Bensport La Sarthe – the prototype of which was road tested in Octane 142 – is an excellent illustration of Envisage’s lowvolume creations. Bob Perry of Bensport, a Somerset-based Bentley and Rolls-Royce specialist, imagined a racily bodied, R-Typebased Bentley competing at Le Mans and got a metal-working company in Poland to build a prototype body to his design. The resulting coupé, all wood and leather and raciness, turned out well and Perry is offering further Les Sarthes – a maximum of 24 – for sale.
Envisage has scanned the prototype’s body and created a buck computer-milled from ‘Ureol’, that green polyurethane tooling board. ‘It’s hard enough to resist hammering,’ says Andy Hunter, director of Envisage
Manufacturing Ltd, where all the old skills overlay an accuracy of buck-creation undreamed-of in the past. ‘We’ve improved the Bensport design where needed, and we’ll make the body in fewer sections than they used in the prototype.’
An R-Type chassis sits nearby for trial fittings, and the marrying of body to Bensport’s refurbished, upgraded chassis and mechanicals will be done at Envisage – the first one by Christmas. We watch workshop supervisor Matt Godsell forming a piece of body on a wheeling machine, the once-flat sheet of aluminium gradually gaining a double curvature as it’s passed back and forth, squeezed between the machine’s convex wheels.
‘Would you like a go?’ he asks. It looks easy but, as my curve heads uncontrollably off-kilter to make a shape no car is ever likely to need, I discover that it’s not.
Envisage runs an apprenticeship scheme, currently with 12 recruits helping to keep the old skills alive and mesh them with new ones. Godsell was an apprentice: ‘I used to work in a café outside Coventry Prototype Panels. One day, one of the apprentices there was telling me what he did. “I want to do that,” I said, and now I’m doing it.’ And what was CPP is nowadays in the Envisage Group.
Bucks for hand-formed XKSS panels, reverse-engineered by scanning original cars, are also much in evidence. It’s intriguing to see how adjacent sections are placed together, edge-to-edge, and held with bridging tabs and self-tappers while the butt-welding happens. With welding complete, tabs removed and the surfaces smoothed, the join is near-enough invisible.
On the way over to the XKSS build area on the workshop’s far side, Shaun – another magician in aluminium – tells me how he used to work at Abbey Panels like his father and grandfather before him. He points to an Echold shrinking and stretching machine and a metal folder: ‘They came from Abbey Panels.’ There’s a DB Speedback body, an Aston Martin DB6 restoration for The Aston
‘Wheeling looks easy but, as my curve heads offkilter to make a shape no car could need, I discover that it’s not’
Workshop, and now here’s Number Eight of the XKSS continuation cars with its brass windscreen frame and its beautifully brazed engine cradle from Arch Motors, a long-time fabricator for the racing fraternity. The original Jaguar D-types and XKSSs were built from structures fabricated by subcontractors, and it’s no different today apart from being a lot more accurate.
And what’s this in the corner? ‘We’ve bought a small press, which we’re going to have a play with,’ says Andy Hunter. ‘You fill it with Jewelite B3 molten metal, push in the piece that you want to press more of, and make a mould.’ That’s soft tooling, perfect for making short runs of repair panels.
WE LEAVE THE metal-shapers and head to CGI, or Concept Group International, recently bought by Envisage and located in Doyle Drive. We’re met by Sammie Mayers and Kate Webster, design-school graduates and now CMF (‘colour, materials and finish’) designers. They analyse trends in design, drawing inspiration from the worlds of art, fashion and culture, they research new materials such as ‘mushroom leather’ (made from fungal fibres), orange-peel leather and spray metal finishes, and they propose these new ideas to carmakers.
There’s a new trim shop in which these ideas can be realised, and which can trim the concept cars and prototypes that take shape on CGI’s ground floor under the guidance of production director Mick Bradley and design director Oliver Le Grice. And it’s here that new designs are created, as the wall display of the work of the Coventry University Summer School – the students were asked to re-imagine well-known designs for the modern era – shows.
So Chris Devane, Envisage’s CEO with British Leyland, Lotus and Bentley on his CV (‘I started at Triumph in the middle of a strike’), now runs a wholly British creative powerhouse right in the middle of Britain’s motor industry heartland. Metal-bashing is alive, well – and a whole lot cleverer.
‘Original XKSSs were built from structures fabricated by subcontractors. It’s no different today, except it’s more accurate’