Stories of inaccuracy and instability persisted. Resistance to rapid prototyping was widespread, and was in danger of becoming entrenched. The partners would only reap the commercial rewards of the project's technological developments when rapid prototyping techniques were actually put to use. Now that their technical failings had been addressed, it was essential to show development engineers exactly how these techniques could help them. First, the selection of appropriate modelling materials and technologies had to be simplified.
Choices depend upon the use to which the model is to be put, but are often highly complex.
Stereolithography, for example, gives good surface quality, suitable for a single design part which is to be finished and painted. Laser sintering, on the other hand, uses a more stable material and produces a surface quality that is adequate for a mock-up. BIBA built expert system software with a front end designed to help non-specialists to choose the right rapid prototyping process for a particular task. Their 'Rapid Prototyping System Selector' package matches modelling materials and build technologies to information about the intended application of the model. Secondly, engineers had to be persuaded that rapid prototyping could really help them.