Today's designers take rapid prototyping pretty much for granted - having a three dimensional model of your design in your hand just hours after creating the CAD files has become the norm. But the technologies that allow these prototypes to be created continue to develop and one of the most innovative launches at Frankfurt's Euromold fair last December was the new Digitalis prototyping technology.
Developed by Huntsman Advanced Materials, the new Araldite Digitalis rapid prototyping additive fabrication system has been designed to deliver speed, accuracy and ease of use, according to its developers. At the core of the Digitalis machine - and key to its high performance - is the Micro Light Switch (MLS) collimated UV light exposure system, which enables selective exposure of the custom-developed UV light curable Araldite resin to be directed and controlled via a micro lens over a large area.
The company said that one of the features that sets its Digitalis system apart from other additive layer fabrication systems is that it does not use either lasers or the light reflecting micro electromechanical systems (MEMS) used in more conventional prototyping (or 3D printing) systems. And the light beam in the Digitalis equipment is always directed at 90 degrees to the surface, not at an angle as in some other technologies.
Huntsman chief technician Ole Hangaard said at the show: "Munich and Vienna universities performed fundamental work on the type of photo initiators for the Digitalis technology that was absolutely key for us." He said that as a result the Digitalis machine is highly productive, with speeds up to three times faster than an SLS (selective laser sintering) machine when benchmarked against a hearing aid reference part.
This speed advantage is due to the use of as many as 40,000 pixels of light in the Digitalis exposure systems, rather than the single dot exposure of laser systems. Hangaard said this makes the system well suited for simultaneous rapid prototyping work or for rapid manufacturing of complex components.
A handful of customers are already benchmarking the Digitalis machine in both application areas, Hangaard said, although he acknowledged that a "step change" is needed in the industry before rapid manufacturing becomes a mainstream application.
Rapid technology industry consultant Terry Wohlers is a close observer of the additive manufacturing sector. He maintains that the market needs new technologies to make the move from rapid prototyping to rapid manufacturing. He clearly considers the Digitalis technology as a step in that direction. "It is an industry first for a chemical company to develop a machine technology and, with 40,000 spots of light striking the resin, the system is clearly much faster than a vector raster system," he said.
Weighing 2,000kg and with machine dimensions of 1.8m by 1.5m by 2.0m, the Digitalis provides a build envelope of 650mm by 370mm by 600mm. The machine is equipped with two UV light bulbs and runs on software developed by rapid manufacturing specialist Materialise and based on its Matrix support structures.
The special Digitalis resin is available in one natural colour, but more options are coming, said Hangaard, with an ABS simulant resin in the development pipeline.
Meanwhile, in the software sector Autodesk, which in the summer of last year added Moldflow to its business portfolio, travelled to Euromold with its Inventor Plastic Features software. The company says that the new software is an independent version of Autodesk that does not need a previous Autodesk Inventor installation. It is claimed to enable a much clearer and faster design of plastics parts, with modelling of thin walled components and typical features such as grids, snap fittings and bushings largely automated.
Wolfgang Lynen is industry marketing manager for the mechanical and machinery area at Autodesk. He said the Autodesk Inventor Tooling Suite has already been launched in China and Brazil, both areas with strong toolmaking industries. In fact, some of the software has been designed in China, he said.
Lynen claimed that Autodesk is now the third largest parametric modelling and drawing software supplier worldwide in terms of sales with 9m licences sold. "We are doing well," said Lynen. The Inventor software incorporates a number of useful features for designers. It can already show whether a part can be moulded - for instance, whether draft angles are correct - using its coloured graphical interpretation and can develop split lines automatically. The next version is likely to include sprue system generation.
Despite the recent acquisition of Moldflow, Lynen made it clear that the Moldflow and Autodesk Inventor software are outside of the Autodesk Inventor Plastic Features product at the moment. However, he said the company is investigating how it can integrate some combinations. "The CAM part still seems to be missing here. We have some integrated solutions in Inventor, however, from third parties such as SolidCam and OpenMind."
Mouldmaker Bloecher showed its capability to incorporate temperature control into aluminium rotational moulding cavities, achieved by integrating stainless steel pipework into the aluminium shells as they are cast. The result of a project commenced several years ago by the company, the resulting geometrically optimised close contoured "circuit of stainless steel veins" in the aluminium moulds enables fast heating and cooling with highly precise temperature control. This can result in an advantage in shorter cycle times and reduced distortion in moulded parts.
Rotomoulding is becoming an increasingly important market for this tooling technique, according to the company, as the thin wall thicknesses of 8 to 10mm used in the industry have traditionally called for exterior heating. Bloecher can now cast the temperature control system with the mould itself, resulting in higher heating efficiency and offering potential for savings in energy consumption.
The central feature on the EOS stand was its presentation of the new Eosint P800 machine and the associated high temperature PEEK HP3 polyacryletherketone (PAEK) material, which is claimed by EOS to be the first laser sintering system worldwide available for operation at up to 385ºC.
EOS said at Euromold that the new P800 system can build PAEK parts in 120 micron layers. Peter Klink, managing director of sales at EOS, said the PEEK HP3 material "is the highest performance material in the PEK family". He said that two EOS customers have been evaluating the material, one for a year and the other for two years.
From the parts on display on the company's stand it would seem Alphaform is one of those companies. EOS displayed headlamp reflectors that the company had produced in the PEEK HP3 grade at the show, adding that the material had been selected to withstand metallising process temperatures of up to 260¡C and lamp operating temperatures of up to 240¡C.
The two other PEEK HP3 applications on display included a hybrid process chamber window made of a combination of a PA 2200 base with a sliding inspection window frame in PEEK HP3. This was said to be capable of withstanding exposure to hot process gases at 180C.
The third application was a racing cycle seat post incorporating a hollow structure to reduce weight. In this application, the PEEK HP3 material was selected simply for its outstanding mechanicals.
Other new developments from the company included its flexible PrimePart ST (soft touch) material. Demonstrated in the form of a flexible airtight hose, EOS claims this is the first flexible layer manufacturing material that does not require a post treatment to make it gas-tight. PrimePart ST offers an elongation at break of up to 250%, making it suitable for applications ranging from shoe soles through to seals or hoses.
EOS also showed its latest IQMS system that provides voxel-to-voxel document information (a voxel is the three dimensional equivalent of a pixel). It also said that its IPCM-M integrated powder management system has now been extended to include all EOS platforms.
French company Missler presented new additions to the 2009 version of its established TopSolid software, including a new collaborative working feature enabling a number of people to work simultaneously on the same tools.
TopSolid 2009 now also includes an enhanced on-screen display of mould cooling circuits, together with improved checking routines for possible collisions between tooling features. This also includes recognition of overlapping cooling channels, a feature that can save a considerable amount of tool design time, according to the company.
Missler also said it would be able to distribute a pre-release version of its TopSolid 7 mechanical design software this month. This is said to be a completely new product and will allow CADCAM functionality to be integrated by 2010.
Missler claims to now be the largest CADCAM software supplier in France and the eighth largest worldwide. The company operates four development centres in France, located at Evry, Grenoble, Lyon and Toulouse, and turned over €27.4m last year. International sales account for €7.5m and are split 38% Europe (outside of France), 42% Asia and 20% in the Americas. The European region of Germany, Austria and Switzerland - DACH - accounts for 33% of its exports and is the fastest growing sector.
One of the key strategies for Missler in the DACH region is the integration of TopSolid CAM with the other leading CAD software systems, including SolidWorks, SolidEdge and Inventor. Prime customers in the DACH region include automotive industry mouldmaker Werkzeugbau Kršger, which has three installations each of the TopSolid Mold, Design and CAM package and one installation each of Electrode and Wire. Thermoforming tooling maker Marbach also has 25 Missler systems.
Voxeljet exhibited the latest version of its VX500 machine, a small to medium sized 3D printer that uses a plastic powder and binder building technology. The machine was previewed at K2007 as a sister to the company's larger VX800 model, one of the latest sales of which was to Ford's Dunton research centre in the UK late last year.
The first VX500 printer has been running at the faculty for fluid and micro-fluid technology at Rostok University, where it is being used in a newly established competence centre for generative production processes for medical equipment. It is the first rapid prototyping machine to be installed at the university.
Voxeljet said it has since supplied a VX500 machine to the plastics and metal rapid prototyping specialist Portec, which is based at Zella-Mehlis in Germany. Portec is said to be using the machine mostly to produce PMMA prototypes, using epoxide, polyurethane and acrylic infiltration materials.
Features of the VX machines include 100% material recyclability and room temperature printing. The 500 machine measures 1.8m by 1.8m by 1.6m and provides a build volume of 500mm by 400mm by 300mm. Build layer thickness is 100 microns, with the machine using 4 micron particle size powder.