Engineers build 3D printer for making plastic parts

Engineers at De Montfort University (DMU) in Leicester are building what is hoped to be the world’s fastest 3D printer for manufacturing high-performance plastic components. 

The machine, which will print and fuse fine polymeric powders to make complex parts on demand, is the intended result of the £750,000 SPRINT project funded partly by the Technology Strategy Board.

DMU has partnered with manufacturing specialists from MTT Technology, Renishaw and Parker KV to develop the machine’s core technology, an additive manufacturing process known as selective laser printing (SLP), for use with high-performance polymer materials such as the thermoplastic polyether ether ketone (PEEK).

Additive manufacturing techniques, which rely on a range of laser-based or advanced printing techniques to build up models layer by layer from scratch, are viewed as a potentially more economic alternative to subtractive production methods that remove sometimes as much as 95 per cent of raw material to craft a component. In depth coverage from The Engineer can be read here.

While the technology has been taken up by industry, its applications are limited. This is because current units are unable to compete with the quality and speed of conventional manufacturing techniques.

Jason Jones, who is leading the project at DMU, hopes to develop a machine capable of depositing layers of high-performance polymer powders at rates comparable to the time it takes a desktop printer to churn out a sheet of A4 paper. At this speed, he said, a complex component for perhaps an aircraft or a car could be built in less than 20 minutes.

Jones said that an SLP machine moulds polymer powders into components by first charging them with static electricity. It then uses a CAD-controlled light-emitting diode to trace a desired shape onto a photoconductor surface. Due to electrostatic force, the powder particles will ‘jump’ onto the surface at the locations traced out by the light.

The machine fuses each layer using controlled heat and pressure. According to Jones, this is a unique feature because most 3D printing processes use negligible pressure. ‘The application of pressure gives a much higher density and integrity throughout the part,’ he said.

Paul Gray, manager for advanced manufacturing technology at Parker KV, said that his company is looking to use the technology for printing crucial and complex aeroplane components such as manifold systems.