In 2007, while hand-assembling the 1001-horsepower, 253-mph Veyron 16.4 supercar, Bugatti engineers noticed how its body materials of aluminum and carbon-fiber blend into a unique and beguiling two-tone finish of highly contrasting light and dark hues. At the 2007 Frankfurt Motor Show, Bugatti pulled the sheet off its Veyron 16.4 Pur Sang, a special unpainted version of the Veyron with a body of highly polished aluminum and naked carbon-fiber.
AUTOart has achieved its own “pur sang” edition. As with the real car, the AUTOart Bugatti Veyron 16.4 Pur Sang has a body of aluminum that is painstakingly hand polished to a mirror finish to contrast perfectly with the replica carbon-fiber center panels – producing the exact stunning visual effect that Bugatti intended to create in 2007.
Compared to a conventional painted model, AUTOart reports that their process of making the 1:18-scale Veyron Pur Sang is slow, expensive, and time consuming. To accurately reproduce the Pur Sang’s exterior finish, AUTOart’s engineers switched from zinc alloy — the common user-friendly material for die-casting model car bodies — to actual aluminum, far trickier to work with. AUTOart learned that the hard way when it produced its first polished-aluminum model, the acclaimed Ford GR-1 Shelby Concept Car.
TECHNICAL CONSIDERATIONS IN CHOICE OF ALUMINUM
The choice to take on the challenge of working with actual aluminum did not come lightly. For the Veyron Pur Sang, AUTOart rejected zinc because, though it can also be polished to a mirror finish, if left unpainted it will oxidize within days as humidity corrodes the metal surface. A clear coat can be applied to prevent this oxidation, but the clear coat appears as a heavy layer that alters the look of the finished body. A clear coat can also degrade over time in direct sunlight. Chrome plating the zinc is another way some model producers replicate polished aluminum. But a chrome finish is too bright and doesn’t have the same surface depth or texture as actual polished aluminum.
The only choice for AUTOart was to go with aluminum alloy, even though the raw material is more expensive and the aluminum, with a higher melting point than zinc, attacks the die-casting mold and shortens its life. A mold injected with molten aluminum may last for only 1/10 as many “shots,” or die-casting cycles, as one injected with zinc.
Once the Pur Sang’s body is cast in aluminum alloy, most of the work is by craftsmen. While a conventional zinc body needs 45 minutes of labor to trim and prepare for paint, three hours worth of labor is expended to trim, sand, and polish each Pur Sang body to its glossy finish. The contours of every bare panel, from the bumpers to doors to bonnet to the quarter-panels, must align as perfectly as on the real car. That is a difficult standard to achieve in mass model production! Up to 50 percent of the die-cast aluminum alloy bodies are rejected, scrapped, and recycled due to over-polishing and minor blemishes introduced during polishing.
The only authentic way to replicate Bugatti’s Pur Sang masterpiece is to use genuine aluminum alloy and polish it to get the same look and texture as the real car. AUTOart undertook this model for the same self-validation that Volkswagen committed to the Bugatti Veyron in the first place: this is how great a car we can make!
OWNERSHIP MAINTENANCE ADVICE
As with the real Veyron Pur Sang, the finish of the AUTOart 1:18-scale model requires some maintenance. Aluminum alloy is also subject to oxidation at a very slow rate in dry and indoor condition and the surface will slowly turn dull after one or two years. Happily, as with tarnished silverware, it is easily re-polished to make the model look brand new. Owners can use any commercially available tarnish remover such as Brasso or Autosol, or any aluminum polishing cream such as 3M Marine Aluminum Restorer or Mothers Mag and Aluminum Polish. As you polish your model, you can be certain that somewhere, in some beautiful garage, somebody is doing the exact same thing to the body of a real Bugatti Veyron 16.4 Pur Sang.
- polishing aluminum parts : 148 minutes of trained manual labor
- trimming of all metal parts: 35 minutes of normal manual labor
- trimming and machine-cut opening of parts : 58 minutes of normal manual labor
- manual drilling of small holes : 34
- manual spray paint : 116 processes
- tampon printing : 47 hits
- number of components : 271 pieces
- hot stamping area : 12 spots
- development time : over two years