3-D colour rapid prototype modelling

3-D colour rapid prototype modelling

Keywords Umak, Rapid prototyping, 3D

What is believed to be a breakthrough in rapid prototyping model creation is now available from Umak of Birmingham, described as the world's first commercially available 3-D solid colour modelling package. The new system reportedly allows more effective communication values and representative information to be sourced from the model and provides a solid coloured shape that can be handled and was only previously able to be viewed on the screen of a PC.

The new rapid prototyping system, developed by Z-Corporation of America in conjunction with the Institute of Physical and Chemical Research (RIKEN), a leading Japanese science and technology research institution, provides a quick to build, full colour prototyping model in a single operation and at a cost-effective price.

The Z-Corp Z402C rapid prototyping machine is said to be able to produce a model from a pallet of 24 colours and is likely to be mostly utilised to produce 3-D engineering, marketing, education, research, molecular and medical models. Currently, these are created in monochrome and then surface painted or seen solely as screen graphics or in printed formats.

According to Simon Graham, head of Umak's rapid prototyping division, it would be ideal to portray physical models demonstrating a finished component in customer livery or different colours to represent various elements of an assembly, for instance. The model could then be sectioned to show the critical areas and rebuilt in that format on the Z-Corp machine for further discussion.

In proving the system, Z-Corporation has taken virtual reality mailing list(VRML) files from a range of 3-D CAD systems, including SolidWorks, and produced demonstration parts. Also, models have been created directly from colour bitmap slice data.

The Z402C colour machine is reportedly able to create a 3-D model up to 250mm by 200mm by 200mm at a build rate of 17mm per hour in colour and 50mm per hour in normal mono. This is achieved by distributing a layer of non-toxic gypsum powder onto a movable platen, followed by a programmable routine whereby the two-axis head, with 128 individual jets, similar to an inkjet printer, sprays a 14mm wide trail of binder fluid over the model build area.

The spray only covers the programmed build area, leaving the rest of the platen in a powder condition, which is subsequently vacuumed or brushed aside for further use. After each jet pass, the platen is automatically lowered between 0.1 and 0.2mm and the power application and spray process repeated.

In the colour version of the machine, three cartridges containing yellow,magenta and cyan pigment are applied with the clear binder fluid to produce blue, green, yellow, magenta, white, black, red and purple colours. The colours are selected according to the program and sprayed through the inkjets in a 1mm band, around the perimeter of the model as it is progressively constructed. Apart from the outer wall of the model, the centre portion is left in the colour of the neutral binder, which conserves the colour pigment.

Umak goes on to explain that when building a colour model, the Z-Corp machine works at a third of the speed of the normal mono Z402 machine, which is still the fastest 3-D rapid prototyping system currently available. The new machine will also produce monochrome models at normal speed. Existing Z-Corp Z402 monochrome machines can be upgraded to colour and switching between colour and monochrome cycles takes around 15 minutes to accomplish.

Further details are available from Umak Limited. Tel: +44 (0)121 744 8555;Fax: +44 (0)121 744 6222; E-mail: sales@umak.co.uk