While viewing the work of a local artist I noticed a group of three female figures made of what appeared to be white porcelain. I learnt from the accompanying leaflet that the figures were in fact miniature likenesses of the artist’s models and had been created using advanced technology.
The leaflet explained that the figures had been produced from a plastic resin by “selective laser sintering … using the latest body screening technology and 3D imaging software”. While setting aside my thoughts about modern art (I know some of you will like this sort of thing), I did wonder what was meant by “selective laser sintering”.
Selective laser sintering (SLS) is a process that employs a high powered laser to sinter, or fuse together, small particles of metals, plastics, ceramic, green sand or glass. The raw material, known as the powder bed, has to be heated to just below its melting point.
The three-dimensional digital data produced in the design process (or body scanning in this case) is sliced into a series of layers using the imaging software. The laser, guided by the software, draws on the surface of the powder bed to build up each of the layers, which are then sequentially recombined to make the final product.
The system can be used to make complex shapes, although the size of the particles is critical to the accuracy and smoothness of the finished product. Since several items can be made in the powder bed at one time, the system has a high degree of productivity compared with traditional manufacturing processes. Large objects can be made in hollow form to save weight and even flexible items can be produced in this way.
Although the technique was originally developed to make prototypes of machine tools and parts, SLS is increasingly used for limited production runs of a wide range of industrial artefacts and, it seems, to manufacture art.