The Diecasting Industry

New machines were produced at regular intervals each containing innovative designs to overcome some shortcomings of earlier machines, or for use with other alloy systems. By 1927 five diecasting machines were in constant use producing zinc alloy and aluminium diecastings. However, developments overseas were taking place at a rapid rate and units of quite different design to those made here were imported, others were imported during the war. In 1981, Lawrenson Diecastings Pty. Ltd. were to win the Grand Award of the American Diecasting Institute for a zinc diecast air conditioner grille.

Huckson Diecastings of Melbourne had its beginnings in the engineering company, N. J. Huckson and Co. of Wagga Wagga, NSW, a company which was re-established in Melbourne in 1929. Shortly before this H. J. Huckson had designed a diecasting machine for which the first Australian patent was granted for this type of unit. With this unit, a range of aluminium-bronze alloy articles such as gas taps, hardware fittings and bronze nuts and bolts was cast. Another machine was built in 1936 when mass production started with an order for 200,000 drum seals in two sizes. Hucksons also produced diecastings for the businesses of Henry Lane in Newcastle and Edwin Wood in New Zealand. In 1977 the Company was the winner of the AZDA Award of Distinction for a redesigned diecast soap holder which increased productivity so that profit per kg metal sold, increased from $1.62 to $3.96.

Many other Australian firms entered the diecasting industry between 1950 and 1970 as the industry increased manufacture of components for mass produced cars, domestic appliances and builders' hardware. In Australia, the Society of Diecasting Engineers was formed to improve education and technology transfer in the industry, while the Diecasting Institute brought the management together at a common forum. It was appreciated that in the industry as a whole, instrumentation and control were less than optimum and there was considerable variation in the quality of product.

A co-operative technical development programme led by a CSIRO team was instituted which also brought in technical representatives of the metal supply industries. In 1973, CSIRO produced the first pressure diecasting in Australia where the important manufacturing parameters such as flow rate, pressure and temperature, were measured. From such work, instrumentation was developed that could be applied to machines in the factory. This led directly to much improved machine and die designs. In addition, it showed that reduced casting pressure could be used, allowing the castings to be made on smaller machines at lower cost. Rapid progress was also made in designing for thin (less than 1 mm) castings which placed the Australian industry ahead of the world in many aspects of diecasting technology, particularly as it related largely to zinc base alloys. A survey in 1984, however, indicated an increase in the number of firms concerned with only aluminium base diecasting and there is evidence that the pre-eminent place the Australian industry enjoyed some years ago, is being lost.

Australian Academy of Technological Sciences and Engineering