The major vehicle manufacturers General Motors Holden, Ford, Chrysler, Volkswagen and British Motor Corporation all installed presses (some as early as 1925-26) to produce, first of all, body components and later all steel bodies. The steel body building aspects of the industry, with its important implications for the steel makers, was an important factor in Government decisions requiring mandatory local content by vehicle manufacturers.

The changes in motor car body design followed the overseas trends, from open seating to soft top with rolldown sides, and gradually the development of an enclosed body. From a manufacturing viewpoint the introduction of the first all steel body in 1937 effectively began a new era of design and body building. Progressive changes in engineering design gradually replaced the traditional chassis-body arrangement with monocoque intergral construction, using sheet steel sections throughout and so the importance of stamping capability increased.

Because the economies of steel stampings is directly related to the cost of the individual die sets necessary to form and produce the panel and the volume of production, the relatively low scale of production in Australia necessitated the lowest cost tooling which would do the job. This problem initiated a whole variety of ingenious solutions, some with great compromises. Nevertheless, Australian press techniques, as developed through necessity, came to be recognised as a standard in low volume tooling practice. Stamping die sets normally made of cast iron with steel inserts for high wearing application or trimming, were unreasonably expensive for Australian volume and all kinds of substitutes were used, ranging from wood, concrete and plastic draw dies with a whole variety of trimming, forming and piercing methods using bandsaws, nibblers and even hammering over formers to reduce tooling cost.

There were, of course heavy increases in manpower to undertake these substitute metal forming methods and inevitably a price in quality, but this labour cost was directly related to the part produced, whereas tooling cost is sunk and is only amortised as the volume eventuates. The early years of all steel body building demanded uncommon skill in sheet metal work, where the hanging of a door into an opening of dubious dimensional accuracy, required great experience in the use of rubber hammers, levers, solder, heat application with a torch and metal finishing.

As local vehicle manufacturing increased, Australian manufacturing engineers faced the continuing problem of developing production processes which would not only ensure a quality part but also at a cost which recognised the low volume and hence restricted investment. Selection of appropriate manufacturing techniques with the optimum level of investment to achieve lowest production cost at a given volume became a highly developed skill in the industry. In latter years many of these techniques were transferred to other countries in the Asia-Pacific area as they struggled to establish an automobile industry initially at very low volume.

Australian Academy of Technological Sciences and Engineering