Materials technology
at ANU

CSEM home

last modified
April 2003

An object being created within the FDM8000. Prototypes are constructed by building them up layer by layer.

A prototype turbine created by the FDM8000.

The FDM Rapid Prototyper
Turning abstract thought into hard plastic

Artists, scientists and engineers are constantly generating clever designs and constructions using the computer. There's a lot you can do with a 'virtual object' , however, to fully appreciate a design it helps to hold it and examine it from a number of angles. The FDM Rapid Prototyper allows you to do just that, convert a computer design to a working three dimensional hard object.

The Computer Art Studio, as part of the National Institute of the Arts, operates a rapid prototyping machine for producing three dimensional hard copies of computer generated designs. The machine is called the Stratasys FDM8000 (FDM stands for Fusion Deposition Modelling).

Once an object has been modelled using Computer Assisted Design (CAD) software, the object is analysed and sliced into hundreds of thin layers (up to six layers per mm). These cross-sections are then laid down one by one in fast-setting, white, molten ABS plastic. Each layer fuses onto the layer underneath. As the layers build, the design takes form.

Where required, support structures are added in by the machine. These are laid down as brittle grey plastic, and serve as scaffolding to support the model as it grows. When the prototype is finished, the support plastic can be broken away leaving the model by itself.

The ABS plastic is a rigid and strong material. It can be sanded, painted, drilled and tested in a number of ways. There's even a 'medical grade' ABS for the creation of prototypes that can be used directly in clinical trials. Objects can be designed so that other materials, like metal-strips, can be inserted during the building process, producing objects of composite material.

With an upgrade, it's even possible for the rapid prototyper to create machine prototypes with moving parts. The process uses a system called 'waterworks' in which the plastic support structure is made of a water-soluble plastic. This is dissolved away when the model is complete allowing for the creation of working gears and moving parts to be created in one treatment - no assembly required.

Besides being used to produce hard copies of computer art, the facility has also been involved in a number of collaborations to generate prototypes of experimental components and designs. Examples includes the incredible PD saddle polyhedra (see the March 2003 issue of Materials Monthly) for Applied Maths, a model of a lens concentrator for the Centre for Sustainable Energy Systems and an extruder for the Department of Engineering.

For more information on the operation and use of the FDM8000, contact Gilbert Riedelbauch (Lecturer in Charge of the Computer Art Studio) on Gilbert.Riedelbauch@anu.edu.au

More information: Gilbert Riedelbauch