Rapid tooling comes of age

Citation

Duncan, S. (2000), "Rapid tooling comes of age", Assembly Automation, Vol. 20 No. 4. https://doi.org/10.1108/aa.2000.03320daa.002

Rapid tooling comes of age

Stephen Duncan

Keywords: Rapid prototyping, Tooling, Moulding

Ask any tool or mould maker what he considers to be the most important issues in satisfying his customers and he will probably say quality and price. Push him a bit harder and he might concede that he sometimes has problems meeting his delivery deadlines. By contrast, if you ask one of his customers the same question, while he may sometimes complain about the quality of the tooling and inevitably grumbles about the price, the overriding issue is the lead time on producing the tooling.

The push to shorten lead times on tooling is primarily coming from the drive to reduce the time that is needed to bring a new product to market. This affects virtually all sectors, but is particularly relevant for manufacturers producing goods in rapidly changing markets. In these sectors, there is often only a limited window in which a product can be introduced into the market: if the product launch is delayed, then the supplier may be beaten to market by a competitor or the market opportunity for the product may be lost.

While making the tooling or moulds is only one of the steps required before a new product can be manufactured, it often accounts for a significant fraction of the lead time, particularly for complex products where many individual pieces of tooling are required. The challenge is to develop methods of speeding up the process of generating tools and moulds. Significant incremental steps have been, and continue to be, made in traditional toolmaking techniques, but the pace of change of demands from the market means that even with the advent of methods such as high speed milling, toolmakers are struggling to adapt sufficiently quickly. What is therefore needed is a step change in the rate at which tools are produced.

Where is such a step change going to come from? One promising route is to extend techniques used for producing rapid prototypes. Methods such as laminated object manufacture, selective laser sintering, stereo-lithography and laser powder deposition have been very successful in reducing the time required to create prototype tools. The question is whether any of these approaches can be developed to produce tooling that is both sufficiently accurate and sufficiently robust to operate in a production environment. Also, the costs of producing tools in this manner need to be comparable with the costs of existing methods: while some customers might be prepared to pay a premium for a significant reduction in delivery time, this premium is unlikely to be large.

Is the goal of manufacturing production tooling at the speed and cost of prototype tooling attainable? Prospects for achieving such a goal are now extremely positive. One approach, currently being developed at Oxford University in collaboration with Ford Motor Company and Sulzer Metco, involves spraying molten metal on to cheaply produced ceramic moulds to create tools and dies for stamping out body panels and other parts. The process, which is already used to produce small tools, will cut to less than four weeks a process that typically requires 15-25 weeks for a new car project.

While not appropriate for every application, the use of this process, and others like it, will increase, particularly when supplying tools and moulds to markets where reduced lead time is an important factor.