Grand Prix Metalcraft

Unsung bastion of the sport

Of all the manufacturers who contribute to the production of racing cars, the ones who receive the least glory for the most noticeable association seem to be those who supply the bulk of the metalwork. Cosworth, Goodyear, Hewland and the like receive accolades, but where do those monocoques originate, where are those aerodynamic wings fledged and whose skill prepares those beautiful, alloy tanks for the crucial lubricant? One of the answers is Maurice Gomm’s firm in Old Woking, whose light I removed from under its bushel in the December 1973 issue of Motor Sport. Practically in parallel to Gomm, and much closer to Standard House’s doorstep, are Grand Prix Metalcraft. Hidden away down a puddle-filled, cobbled alley, Thane Villas, off the Seven Sisters Road in North London, their slightly dilapidated, two-story premises look out of keeping with the high-finance, sophisticated and clinical world of Formula One. Inside it is a different story: one of shining alloy, skilled craftsmen and a valuable contribution to the motor racing and rallying arena at large. Grand Prix Metalcraft supply wings for nearly all Formula One cars, provide an off-the-shelf range of wings for most other formula cars and produce a comparatively enormous quantity of dry sump oil tanks, foam-filled fuel tanks and associated containers for practically anything that moves in the four or two-wheeled world of competition motoring. One-off monocoques, prototype bodywork and replica alloy panels for vintage and classic cars all emanate from Thane Villas along with motorcycle frames and forks and such diverse and unusual constructions as sculptures to be set in the middle of Scottish lochs, replacement copings for Georgian houses and modern furniture.

Behind this eternal spring af aluminium goods are brothers Peter and Bob Hingerton, partnered by Alf Goodenough. All three are products of the aircraft industry, apprenticed together for seven years in the sheet metal shop at Handley-Page, Cricklewood. From aircraft the three moved together into the luxury car sphere, first at Rolls-Royce, Willesden and then Aston Martin, Newport Pagnell. None of them were interested in motor racing at the time (football occupied their spare time), but by chance rather than out of enthusiasm Peter took a job with Roger Nathan Racing as a sheet metal worker on his largely wooden-bodied Nathan cars. Meanwhile the other two had moved to Handley-Page, this time at Radlett—”there’s a lot of gypsy in sheet metal workers—we tend to move around a lot.” Peter, GP Metalcraft’s Managing Director, says, “I hardly knew motor racing existed when I moved to Nathan, but there I saw the potential in racing for a sheet metal fabrication market, oil tanks and such things.”

Inspired by the potential, Peter drew together the old threesome to set up business at Lynton Garage, Fortis Green, where Nathan, Paul Hawkins and several others had premises. Amongst the first jobs they did was bodywork on the aerodynamic Aston Martin Project 212 and a complete body for Sid Marler’s attractive Ellova clubman’s car. And, of course, work came in from neighbours Nathan and Hawkins. What made the business project economically viable, however, was a contract to supply “chopper” motorcycle frames to the United States. Since then that “chopper” market has been something of a gold-mine: GP Metalcraft have supplied over 2,000 sets of peculiar, chrome-plated, steel, “springer” forks, for instance.

The trio are far from the image of smart-suited company directors. For them it’s overalls and dirty hands, continuing to employ their skills on the workbench along with their 12 employees. Peter is the administration man, working for half the day from an office with a wall covered with photographs of his firm’s motorised achievements. In the afternoons the Managing Director quits his office for the shop floor, where he does the majority of the welding. “The rest of them prepare all the metalwork, stack it up and I come along later, when office work allows, to weld it all together.”

Dry sump oil tanks remain their biggest turnover product, particularly for Formula Two and Atlantic. Three standard designs of beautifully finished, cylindrical tanks are kept in stock which cater for most cars on the lines of Escort, Formula Ford and Formula Three. Beyond that one moves into the world of specialised, one-off oil tank manufacture. Peter explains: “Too many people think of oil tanks as simply containers. They’re not. Besides containing the oil they perform the vital function of removing the air from it—the tank must have a good de-aeration system.” This is achieved by a clever system of baffling, but, “what you really need is depth. If you could make the tank skinny, long and deep enough you could do without baffles, but this isn’t practical. People come in and say ‘can you chop 6 in. off the bottom of this tank?’ but you can’t because the oil would just surge up the sides. They spend a fortune on the engine, but don’t think of the oil tank as important. Occasionally, shallow tanks are required for awkward sitings and these have to be comprehensively baffled inside, like an egg-box. But we only make these at the customer’s own risk, in case an engine blows. Fortunately most people are beginning to realise how important an oil tank is and are building things round the tank instead of throwing in the tank last in any old position, such as straddling the gearbox. In Formula One, most designers have their own ideas for efficient tanks, which we construct for them.”

Whether it’s a pint tank for a motorcycle or a Formula One tank, they’re all made the same way. Aircraft specification L59 alloy sheet is used whenever possible, for its softness—harder material is more susceptible to cracking during welding. The sheets are bent to shape, wealed by hand if necessary, the complex baffling system welded inside along with the pipework (inlet at the top, outlet at the bottom), assembled with the aid of a jig, and the end-caps welded in place. “We try to gas-weld everything because it’s a lot quicker than the argon arc method and produces a much flatter weld,” explains Peter Hingerton. “You can’t help building up the weld with argon and its a lot more brittle. We only use argon round heavy unions.” The finished weld on GP Metalcraft tanks is a work of art, regular and flat, a tribute to aircraft-standard training. “It’s a matter of practice and experience, like riding a bike,” he says, modestly. The welds are not disguised and the only finishing given to the tanks is polishing. Alloy screw-caps are produced for them by Clive Bracey.

Less complicated to make are the 4-gallon and 6-gallon standard rectangular fuel tanks for competition cars. These are rolled and welded up, leaving one end-cap off to enable cellular foam to be inserted, and then closed up. The smaller tank costs £26, the other £32. Beyond that, most tank production is one-offs, mainly of larger capacities for rallying. Either GP Metalcraft or Gomm fuel and oil tanks are used by the works Escorts, for example. More unusual tanks made at Thane Villas arc some 35-gallon, long-range items for AC Cobras, made for Brian Angliss, whose Cobra Parts firm in Surrey I described in the June 1975 issue of Motor Sport and GT 40 tanks for John Etheridge, who I featured in the December 1975 issue. Still remembered with a certain amount of anguish are a number of Maserati 250F tanks made for Cameron Millar and others. Even Hingerton’s skilled men couldn’t fathom out the system of riveting on the original tank—”we think they must have left an Italian inside there”—and alternative methods had to be used. Somewhat easier items to construct are fuel collector pots, mostly for F2 Chevrons, currently, and radiator header tanks for a number of Monica cars, that Anglo-French project which was killed, leaving British designer Chris Lawrence with a number of unfinished cars to complete. GP Metalcraft are making heater boxes for these, too.

Surprisingly, aerodynamic wing design is much less of a great scientific research effort than one would imagine. “We get normal production wing shapes from an aircraft manual and we just dream up these new, deep, banana-shaped wings we’re doing. But they seem to work,” adds Peter Hingerton. “This is where our aircraft experience comes in. Racing cars are becoming more and more like aircraft, some more sophisticated.” Normal GP Metalcraft wings, constructed from NS4 22 gauge alloy, are rolled up and welded, clamped in a jig and then filled with polyurethane foam for rigidity. For Formula One wings, mostly one-offs, the traditional method of aluminium former construction is employed. Normal wings are sold as complete sets, complete with mild steel stays, plated in the firm’s own cadmium zinc plating plant. Many of them are exported to the USA, which seems to lack its own manufacturers.

Monocoquc production is mainly of oneoff s: “We don’t want the churning-out jobs and we try to stick to Formula One cars. However, we produced the Elden last year.” Shaped aluminium sides are produced for March Engineering to build into their Formula Two and Atlantic monocoques. More recent Formula One work has been on the bits and pieces side—noses, oil tanks, wings and oil cooler ducts. Of late, they’ve produced wings and tanks for the Copersucar and put a considerable amount of work into the Embassy-Hill.

Whatever else they might make, Peter Hingerton confesses that producing bodywork is the most interesting line of business, whether prototype or replica. “On the prototype side, with glassfibre getting more expensive, it pays manufacturers to have an aluminium body built first and then take a mould from this rather than build it up on a clay mock-up.” The body for the prototype Chevron B19 Spider of a few years back must rate as one of their notable achievements in this field. At the moment one section of GP Metalcraft is kept very busy producing new Cobra panels, indeed complete bodies, for Brian Angliss. These are rolled out and shaped by hand to a glassfibre buck. They also mount the bodies to the chassis for Angliss, to ensure a perfect fit. On that GT40 side again, they are the people who repair rusted steel chassis for Etheridge.

Past achievements in the line of vintage and classic cars have included producing new Maserati 250F bodies for Cameron Millar and Innes Ireland, rebuilding two D-type bodies, including straightening the chassis on Martin Morris’s example, making new D-type bonnets, rebuilding a Lotus 11, making a new bonnet for Ray Potter’s ERA-Delage and rebodying two 8-litre Bentleys. “But really, we fight shy of producing complete bodies for vintage cars because of the room they take up and the time they consume,” Hingerton says.

“We had a real eye-opener when the oil crisis came—we realised that if racing stopped we would be out of business,” is how he explains away some of their interesting diversification. The three GP Metalcraft directors formed a separate company, Proto Excel, with racing driver Chris Craft, to manufacture aluminium-based furniture for Craft’s sales outlet. The results are magnificent—and very expensive. As for the sculptures, these are built to the designs of former Groper driver and artist Andrew Mylius; the first, lowered into place by helicopter, graces a reclaimed loch in Fife and a second, about to be made in the same fashion of cladding steel frame in anodised aluminium, will form the centrepiece of a new town at Livingstone in Scotland.

Whether it be sculpture or Formula One wings, GP Metalcraft craftsmanship exudes pure artistry in metal. Pause a while to admire it next time you’re browsing round a paddock or boating on that Scottish loch.