Applied Science: Nick Scott meets the man who oversees the ultra-complex, highly skilled process of painting BMW Luxury Class models

Ponder, for a while, the role of colour in our lives – as a cultural signifier, as a determinant of our behaviour, as an expression of personality – and it quickly becomes clear why it can bolster the emotional connection between a car and its owner. So it’s no surprise that the process of applying pigmented liquid to the shells of motorised vehicles has improved, since four-wheeled automobiles first started trundling along the world’s thoroughfares, as dramatically as the internal combustion engine itself.

In those early years, it was a case of owners applying ordinary paint from the local store with brushes on an annual basis. In the 20s, nitrocellulose lacquers, chrome plating and spray guns raised the game a little; stoving enamels, then acrylics, then urethane and polyurethane paints followed in the subsequent decades. Today, primer baths, electric-current binding, e-coat dryers, dip-coating conveyors and sophisticated robotics are all involved, making a wealth of effects – varying levels of reflectiveness, interesting textures, subtle contrasts, metallic gleams – all achievable.

Which is why people such as Roland Laurer – paintshop manager at BMW’s Dingolfing plant in Bavaria – play a key role when it comes to the emotional bond owners forge with their vehicles. Laurer’s remit is to ensure that his department’s work does justice to the elegant curves and contours of a modern luxury car. “Our job is to enable the design of each unique BMW body style to be coated in a perfect way,” he explains. “There are many challenges to guarantee that every single part of the car – doors, bumpers and bonnets – will look perfect from each and every perspective from which a customer will look upon their car.”

One of the challenges he faces is the sheer number of different vehicle shapes that pass through his department. “Our process is specially set up to allow us to overcome the challenge of having a variety of different models – the 3 Series Gran Turismo, 4 Series Gran Coupé, 5 Series Saloon and Touring, 6 Series Gran Turismo, The 7, The 8 – being produced in our plant,” says Laurer, who is responsible for ensuring that more than 1500 cars are coated with the correct colour with vividly perfect results, from around 48 standard and around 300 custom options, each day.

As with the production hubs of the world’s finest shoemakers and watchmakers, here, the human touch and cutting-edge technology work in synergy with the same ruthless precision as the two blades of a pair of scissors. “We work with 136 robots to apply the paint, without any manual intervention – other than to quality check the work before the car leaves the line,” says Laurer, adding that highly ingenious systems are in place to ensure the plant runs “as efficiently and in as environmentally friendly way as possible”. The quest for perfection can be a gruelling one, and the eagle-eyed checks go on right up until the finished shells leave for the next stage of production: even the tiniest of dust particles must be removed with hand-held smoothing planes.

The logistics, meanwhile, are mind-blowing, and change constantly – especially of late, says Laurer: “It just so happened that, at the same time as the ramp-up of the new 8 Series began, we also launched a new paint process on all lines, which was pretty intense. And, of course, the technical design of the 8 Series makes the process even more complicated: the mix of materials – steel, aluminium, plastic – with the boot lid alone all added up to an enormous challenge for us.” With cars increasingly put together from intelligent formulas that mix steel, aluminium, carbon-fibre and plastics, it’s unlikely the logistical jungle Laurer traverses on a daily basis will get any less dense soon.

Making Laurer and his colleagues’ challenge even trickier as consumer tastes change and the demand for more and more choice grows. “Compared to 15 years ago, when we always had a lot of cars being painted silver, we see a lot of variation – both new shades of colours and variations on traditional ones. We have a large variety of different greys now, and six different versions of white available for our customers to choose between.”

Technological strides are constantly being made, and a big leap forward is about to be made in an area that traditionally required flesh and blood, rather than silicone and circuitry, to be done correctly. Mechanical vision systems are already working wonders in fields as diverse as medicine and farming, and it’s unsurprising that BMW is leading the way when it comes to their application in the automotive arena. “We’re working on highly intelligent camera-based systems which can quality check all surfaces of a car as well as, if not better than, any person. This can only help our goal to deliver the absolute highest-quality finish for our customers,” says Laurer.

It’s only the latest chapter, of course, in an epic narrative – The Quest for Perfection.