Theme: Evolution – From Iron Bars To Plastic Assemblies

The role of the bumper can be inferred easily from the name.

2015 Nissan Altima: where does the body start and bumper end? http://vietq.vn/so-sanh-xe-sedan-honda-accord-va-nissan-altima-d55126.html
2015 Nissan Altima: where does the body start and bumper end? Source: vietq.vn

Originally they were mere metal bars attached to the front of the car, and were visually separate from the wings and grille they were intended to protect. Let’s take a quick look at how they changed over time from a piece of steel to complex plastic assemblies merged seamlessly to the rest of the car.

The Altima (above) shows how far bumpers have come from being horizontal iron bars. The bumper has grown to be a part of the unified form of the car and at the moment is extending upward around and past the lamps, and rearward to take surface space from the pressed-steel elements of the cars. The wing is becoming a smaller proportion of the area of the car, leading to the need for unusually placed shutlines. Where did this all start?

1930 Austin 7. Note the clearance from the bumper to the body and wheels: http://tommy_eliasson.ownit.name/EUbilar/Austin%201930%20seven.jpg
1930 Austin 7. Note the clearance from the bumper to the body and wheels: http://tommy_eliasson.ownit.name/EUbilar/Austin%201930%20seven.jpg

Our first example is a 1930 Austin 7. Notice how the bumper is separated from the other parts, connected to the body by two steel rods. There is a lot of space between the bumper and the wing and grille. The bumper itself is only very slightly decorated, with ribs for additional strength. The small curls at the end are there to provide a simple finish and to reduce the chance of the car hooking onto something during parking manoeuvres. The stylist was not very involved in this, one could say.

1950 Humber Snipe - the bumper is closer to the body but still under the main volumes. Note the over-riders: www.leylandp76club.org.nz
1950 Humber Snipe – the bumper is closer to the body but still under the main volumes. Note the over-riders: http://www.leylandp76club.org.nz
1954 Buick Century: forums.aaca.org
1954 Buick Century: forums.aaca.org
1964 Lincoln Continental: barret-jackson.com
1964 Lincoln Continental: barret-jackson.com

Our second example, a 1950 Humber Snipe, shows the bumper becoming a chromed item, made of pressed steel. It is now closer to the body but still visually distinct. It features over-riders which offer some capacity to vertically extend the protection offered against bumpers of a slightly greater height. In the US a 1954 Buick Century shows the American approach, flamboyant, dangerous and integrated with the grille.

Moving to 1965 the Rolls-Royce Silver shadow shows little advance on the 1950 concept. Around this time in the United States bumpers were far more advanced in terms of integration but of rather less use, as shown on this 1964 Lincoln Continental.

In 1971 the US government decided that bumper design was unsatisfactory. For one thing they were incapable of withstanding damage and had become very costly to repair. The result of legislative changes was that bumpers now had to withstand a 5 mph impact. This requirement vexed the designers whose first response was to separate the bumpers from

1965 Rolls Royce Silver Shadow: wikipedia
1965 Rolls Royce Silver Shadow: wikipedia

the body and to make them stand further forward. Adapting the regulations to existing vehicles was thus something of a challenge as this 1976 AMC Matador coupe. The indicators and tail lamps migrated from the bumper to the body, reducing the cost of small collisions.

1978 AMC Matador. Just like the ´76 for the purposes of this article: bringatrailer.com
1978 AMC Matador. Just like the ’76 for the purposes of this article: bringatrailer.com
Setting the template, the 1971 Renault 5: netcarshow.com
Setting the template, the 1971 Renault 5: netcarshow.com

In Europe it was mostly business as usual, as shown by this 1972 Opel Rekord which is conceptually the same as a 1960s US vehicle. However, Renault’s 1971 Five showed the way forward, in being the first car with plastic bumpers. Note also how it is beginning to show integration of the bumper and the body. For the next twenty-five years, bumpers were generally a variation on this theme.

1972 Opel Rekord. In term of bumper concept, it´s the same as a 1965 Rolls Royce: best-selling carsblog
1972 Opel Rekord. In term of bumper concept, it´s the same as a 1965 Rolls Royce: best-selling carsblog

Some manufacturers managed the transition from bumper to combined bumper-spoiler more effectively than others. Half-way houses involved adding an apron to the underside of the bumper though the metal-work was still there underneath. This is the beginning of the trend to reduce the extent of the car’s body-in-white to only those areas where it was needed structurally.

1983 Volvo 740 - the bumper has a distinctly separate spoiler underneath: http://www.autogaleria.hu -
1983 Volvo 740 – the bumper has a distinctly separate spoiler underneath: http://www.autogaleria.hu

The 1990 Honda Civic shows the same concept as the Renualt 5 but paint has been added and the construction is more complex. The bumper is now formally a part of the

1990 Honda Civic: netcarshow.com
1990 Honda Civic: netcarshow.com

overall shape of the car’s body and the addition of paint means that the aerodynamic requirement of a smoother body plus the need to protect the car is being carried by one assembly. From then on it was a matter of time before the visually distinct bumper vanished into the car’s overall form, with small black strips added at crucial points: bumperettes or bumpers on the bumper.

The possibility of extending the now nominal bumper is being pushed by various manufacturers. The game is to see how far back and how far upward the area made of plastic can be extended. The advantage is that these parts can be more cheaply restyled, potentialy changing much of the car’s character without altering the expensive sheet metal. The trick is to avoid having feature lines cut across the metal-plastic border so that when the front and rear bumper changes the centre section can remain the same.

2010 Peugeot 508
2010 Peugeot 508

PSA have been quite aggressive about this on the 508 and C6 cars. Here is the 508’s rear end. The bumper is quite huge, making this a very complex piece of injection moulding indeed. The trade off is that it can be very hard to manage the continuity of highlights from the metal areas to the plastic. The 508 is an especially egregious example as the flow of reflections is quite poor owing to problems reliably aligning the parts during construction and also the different properties of plastic and metal during forming.

2010 Peugeot 508 rear bumper. The relationshop of the graphics to the forms is tight. Here one gets the idea that the wish to reduce the amount of metal work drove the shutline pattern. It seems expedient.
2010 Peugeot 508 rear bumper. The relationshop of the graphics to the forms is tight. Here one gets the idea that the wish to reduce the amount of metal work drove the shutline pattern. It seems expedient.

Author: richard herriott

I like anchovies. I dislike post-war town planning.

8 thoughts on “Theme: Evolution – From Iron Bars To Plastic Assemblies”

  1. I want to mention the 1977 Porsche 928. Especially the rear bumper is innovative – it is no more a separated part added to the car – it is a fully integrated part of the car.
    Also to mention the clever way to protect the rearlights from contact to other cars and – a horror for joint-fetishists – the obvious wide gap between bumper and the rest for a better response to low-speed-collisions.

  2. The Renault 5’s bumper might be the first all-plastic one, but a mention is due to the 1968 Pontiac GTO and its Endura bumper. Deformable plastic foam, painted in body colour over a metal frame. See it in action.

  3. Cool GTO ad !

    I remember – when i really was a young boy – i was a fan of the TV-series “Dallas”. I do not know why I was looking this boring trash, but I still remember very well Bobby Ewing´s red Mercedes SL, It was the first time I saw the result of Ralph Naders safety campaign – big bumpers that are spoiling the design of many cars completely.

    For me – the most ugly example is the Toyota Starlet – i am sure some Toyota dealers had some sleepless nights when they saw what they should have to sell….

    Checker solves this problem in a very practical manner – they are mounting crash barriers on their Marathon.

    And the 1973 Ford Torino shows the desperate try to give those bumpers a more integrated look

    The Bricklin Safety-Vehicle 1 (but there never was a number two) was a different way to respond to the new safety instructions – and it never found followers. Maybe because it has neither an ashtray nor a cigarette-lighter in order to avoid fire-accidents….

    In my eyes – a good solution was the MGB´s new nose – add some colour to it and it would look pretty modern:
    http://cimg.carsforsale.com/494445/CAF46881-FD95-421B-B8B2-42482D3B87D3_3.jpg.

    The american safety regulations did create a lot of dead-ends in the bumper-evolution. But maybe they were necessessary to push this evolution.(remarkable that for example the Citroen GS with its tiny bumpers did fulfill the new rules without any modulations).

  4. Many of the ‘safer cars’ of the 70s look massively naive now. Few people want to die in a car crash, but its salutary how we, and our legislators, look at risk in isolation. Whilst the NHTSA was fettering the US industry, violent crime figures in the US were rising relentlessly towards their early 90s peak. Not that you can’t address more than one cause, of course and, as Markus points out, the lumpen ‘safety cars’ of the 70s probably inspired manufacturers to come up with the generally more elegant solutions we see today.

  5. We should not forget that a new regulation generally takes some time for the manufacturers to comply with in a satisfying way. For many cars in the 70s, the new bumpers were an add-on to existing structures, and it often showed. Only later the technology was ready to better integrate the bumpers. I see parallels in more recent times. When the topic of pedestrian safety came up 10 or 15 years ago, we often saw cars with ungainly high and protruding bonnets, and the front overhangs grew to unproportional lengths. Only with newer generation platforms, the trend seems to have been reversed in the last few years.
    Examples are not limited to safety topics. Take catalytic converters. The Americans started in the 70s, and they developped engines with a particularly unfavourable ratio of size, power and thirst. The Europeans also struggled ten years later. I remember my ’88 Citroën AX with its electronically regulated carburettor and its rather restricted temperament. It took ten or more years before the engines became pleasant again.

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