A look at some rear bumpers illustrates changes in the way cars are constructed
Around the mid 1980s the bumpers of most cars were quite separate items added to the front and rear of the car’s metal structure or “body in white” as it is sometimes known. If you look at a Volvo 340 in its first iteration, for example, the bumper is a plastic coated metal item wrapped around the wings and front valence. The same goes at the back. Clearly the bumper is not an integrated element of the car and you can see the painted metal all around it.
However, the 1971 Renault 5 kicked off a trend with its single piece plastic bumpers that the Volvo eventually caught up with during a facelift. The newer bumpers attempted to look like one piece items but unlike the Renault, the front valence was still there underneath. Throughout the ’80s old school cars were given refreshes that attempted to make the bumpers look like one-piece items.
What was happening in principle was that the extent of the pressed metal visible on the outside of the car was being reduced. Under the Renault 5’s bumper there were merely some metal brackets to hold the bumper in place along with a lot of fragile bits like radiators and fans. A car like a Series 1 Mondeo is a direct descendent of this construction. Remove the bumper and there are only unstyled components and ugly brackets. Remove the front bumper of a Volvo 340 and the 340’s main shape is still visible underneath.
Moving forward to the later 80s and early 90s, designers at various firms were still slowly extending the bumpers. The main design themes of horizontal shutlines between the body in white and bumper below left a small metal strip between the bumper and the grille or rear lights. The Mitsubishi Colt from a few days back is an example.
I have selected a few “before” and “after” photos to show how the gap between the rear lamps and the bumper changed from being a small metal tab welded on to the rear wing to being a vertical extension of the bumper. This got rid of the vertical groove that was left when the weld was made. I assume such a line was never shown in sketch drawings of the cars but arrived during the productionising process. The result of this is that the bumper has grown upwards, the lamps
extend downwards and perhaps the tailgate is enlarged. By this means the strip of metal between the lamps and tailgate on the upper side and the bumper on the lower side is eliminated.
The advantages are that there is less dentable metal on view and the car can be a bit lighter. This solution also allows a more flexible approach to the graphic aspects of the outlines of the lamps and their relation to the surrounding surfaces. Another effect was to free designers from the clearly horizontal arrangement of the bumper to body shutline and a corresponding freedom to give the lamps newer and sometimes ever more irrational outlines. At the same time the old function of the bumper is hinted at with the residual rub-strip (see the Laguna 2) that still runs horizontally along the assembly. The body in white was receding and the graphics and forms were becoming ever more plastic, in the aesthetic sense. The shutline between the bumpers, lamps and body in white was now free to be placed more or less wherever the designer wanted it and the visible distinction between the body and bumper disappeared.