New Advances in Rapid Prototyping using Inkjet-based 3D Printing

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1 New Advances in Rapid Prototyping using Inkjet-based 3D Printing April 2011 Objet Geometries Ltd. DISCLAIMER: Objet Geometries Ltd. ("Objet") does not guarantee the final release and availability of materials, products and/or features referred to herein. Materials will be released subject to Objet s sole discretion. Not all released materials are currently available for all platforms/systems. Objet will update its website further to releases become available and/or compatible with specific platforms/systems.

2 Bringing Prototyping to the Modern Era Rapid prototyping techniques have found their place in a range of industries such as consumer goods and electronics, automotive, defense, education, motor sports, jewelry, dentistry, orthodontics, medicine, and more. Today it is enabling both large and small companies to simulate complex parts and finished assemblies straight from the printer quickly and more accurately than ever before. Workshop lathes, boring machines, planning and slotting and shaping machines all essential capital equipment for mass production were all invented in the 1800 s. Since the days of the industrial revolution, manufacturers have, until now, never succeeded in replicating and transferring the cost efficiency of mass production to the prototyping process. Prototyping has remained a major Achilles heel for designers and manufacturing companies due to its inability to conform to the economies of scale principle: Architects pay students to painstakingly build and glue cardboard models of their buildings; car manufacturers hire teams to build heavy wood and clay models of their next generation of vehicles; dental labs use bite impressions to design veneers, crowns and orthodontic appliances, and so on. Prototyping has therefore traditionally been slow, tedious, expensive, difficult to repeat, and in some cases, inadequate for the task of simulating the end products they are built to represent. When once it might have taken days, weeks or months to produce prototypes, using 3D printing technologies, the same work can now be achieved in hours. Businesses who want to streamline their efficiency and become more productive can now use 3D printing technology to deliver fast turnaround from initial design to final production of goods. Answering the Requirements of Form, Fit and Function Along with speed, accuracy and repeatability, 3D printing provides the massive advantage of producing realistic representations that can be properly tested and checked for design faults early on in the design cycle. Once a design fault is identified in the model, designers and engineers can simply tweak the design on the CAD/CAM program and print and test again, as many times as they like, until the design is perfected and meets their precise visualization and verification requirements. 2

3 Whereas fulfilling the fit and form requirements of rapid prototyping has always been dependent upon the type of 3D printing technology used, the functional requirements are naturally more dependent upon the properties of the materials being laid down by the 3D printing machine. Fit and Form Testing: Accuracy and Resolution According to industry reports, companies today use 55% of their additive manufacturing processes today for fit and form testing. Fit and form requires an accurate look and feel, so designers, marketers and focus groups can accurately visualize their intended product. So what sort of 3D printing technologies is best suited to simulating fit and form? Inkjet based 3D Printing Technology A cursory Google search for Rapid Manufacturing Technologies will display many competing companies. The main differences between these additive manufacturing technologies are found in the way layers are built to create parts. Some involve melting or softening materials, others by binding powdered material, while others involve jetting or selectively laser hardening liquid materials. Objet Geometries has over 110 registered patents and pending applications in inkjetbased 3D printing technology and a range of over 60 UV curable liquid photopolymer acrylic based materials. These materials are used on specialized 3D printing machines fitted with inkjet heads conceptually similar to regular printers. Providing high resolution, detailed parts, and the ability to print finished model assemblies straight from the machine, inkjet based 3D printing promises designers and engineers the ability to accurately simulate the fit and form of the products they aim to produce, and with the provision of a new range of materials that closely simulate engineering plastics; realistic function testing now comes into play as well. Smooth surfaces Perhaps more than any other technology, inkjet based 3D printing has the ability to produce precisely built parts based on a layerthickness of 16 microns. A closer look at the structure of walls will show that layers are highly integrated, with no log building effect that is typical of many of the melted material deposition (also known as Fused Deposition Molding) 3D printing. 3

4 Choice of gloss or matt finish Inkjet printing also produces parts with smooth surfaces, with a choice of either matt or gloss finish straight from the printer. This is not commonly found in other 3D printing technologies. Minimal post processing Apart from the advantage of using only what you need, jetting the material onto a build tray rather than using Stereo lithography techniques which cures or hardens a selected area within a full vat of liquid resin, means you can jet different materials from the different nozzles of the inkjet head. This has two major advantages over Stereo lithography with regard to fit and form testing: 1. Objet inkjet technology has multi material capability Due to the use of inkjet nozzles that can spray different materials parts can be made of multiple materials or even mixed, composite materials, providing designers the unique ability to simulate complex parts that include both rigid and flexible elements within the same model. An example would be a remote control with hard surfaces and soft, rubber like buttons and over molding grips, essential for simulating the precise look and feel of an end product. 2. Inkjet can use a water removable support material Stereolithography uses the same material for both models and support. This support hardens along with model and must therefore be broken off by hand often leaving flashings and protrusions on the surface that need to be fettled, filed or sanded down in post process. This last point will have a direct bearing on the ability to simulate engineering plastics in the next section. 4

5 New Developments: More Dimensional Stability and Visualization With the release of a new range of materials, Objet Geometries has now further enhanced its fit and form capabilities by providing enhanced dimensional stability and clear transparent properties. Higher Dimensional Stability Transparency & High Dimensional Stability Objet has now released the new Objet VeroWhitePlus a material providing high dimensional stability (the ability to maintain its original dimensions when subjected to changes in temperature and humidity). This is an essential characteristic for fit and form testing, since if a model s dimensions are distorted even slightly, then fitting precise parts together becomes more difficult or even impossible. Objet s newly released Objet VeroClear material produces prototypes with similar visual properties to PMMA, a common glass substitute used when light weight and resistance to shattering is important and where the index of refraction and light transmission qualities are required to be comparable to regular glass. Common applications for this material include lighting covers and cases and glass like elements in consumer goods, consumer electronics and cosmetics packaging. Answering the Requirements for Function: Engineering Plastics Simulation Functional testing is an essential requirement for the rapid prototyping process and in many cases requires the simulation of engineering plastics. A major player within this market is Acrylonitrile Butadiene Styrene, or ABS by its commonly known acronym. 5

6 Why ABS? In terms of price performance, ABS represents an important benchmark for 3D printing due to its ability to combine the strength, rigidity and surface quality of acrylonitrile and styrene polymers, the toughness of polybutadiene rubber, but with the lower price point associated with standard plastics. The list of applications for ABS is long and still growing. Its light weight and ability to be injection molded and extruded make it extremely useful in a wide range of manufacturing products including automotive trim components, enclosures for electrical and electronic assemblies, protective surfaces, home appliances and toys. ABS Like Toughness Objet s new ABS like Digital Material (RGD5160 DM) has a temperature resistance of 65 C out of printer, 90 C with post thermal treatment and a high toughness of J/m. This is comparable to standard ABS and three times the toughness of the Objet VeroGray material. This uniquely tough and light photopolymer material is actually a composite digital material created by jetting two different materials simultaneously both a high temperature material and high toughness material. This is a capability unique to inkjet based 3D printing, and the Objet Connex Multi Material 3D printer in particular, and cannot be replicated by any other 3D printing technology currently available. Using this technique, manufacturers can utilize the high accuracy and resolution of inkjet for fit and form testing, and also the engineering plastic quality for functional testing. The Objet ABS like Digital Material can be used to: Simulate snap fit parts including models and prototypes with moving parts and compositions. Simulate living hinges that go through repeated flexing and bending such as clips and fasteners. Endure high stress usage such as falls and blows or high pressure. Withstand outdoor environments where hot and cold weather would typically cause material deformation. Simulate contact surfaces such as knives, scissors and other cutting surfaces. 6

7 High Temperature Resistance To produce parts combining high surface quality, fine details and 80 C resistance is not easy to achieve by any prototyping standards. Objet s new High Temperature material (RGD525) combines high surface quality with a heat resistance of 65 C out of the printer and 80 C after a short ovenbased post thermal treatment. Light testing The primary applications for this material are thermal testing of static parts. This can include light testing under prolonged strong lighting such as is required for various automotive and heavy industry design projects. Hot water and hot air flow testing Another application involves running hot water through a tap at 65 C a process that typically requires hours of testing. The main advantage of inkjet based 3D printing for hot water testing is clear. Whereas before, customers would have to produce an actual production part very much at the end of the design process, this is no longer the case. A tap can be tested straight out the printer and still mimic the precise look and function of a tap without any of the log building effect typical with Fused Deposition Modeling style 3D printing. Metalizing, painting, gluing Objet s High Temperature material is also ideal for painting, gluing and metalizing, which all require highly smooth surfaces. Post processing of this sort with Objet s High Temperature material is rapidly and easily achieved, without the filing down or fettling of unwanted protrusions that may be typical of other methods such as Stereolithography. 7

8 Summary One of the biggest challenges of 3D printing today is how to achieve allround high scores for fit, form and functional testing. As shown, only inkjet based 3D printing technology currently has the ability to produce the fine detail printing, ultra thin layers, smooth surfaces, high dimensional stability and clear transparency required for fit and form testing. In addition, Objet s unique ability to print multiple materials, conveys a clear and significant competitive lead over both Fused Deposition Modeling and Stereolithography in the fit and form departments. With a new range of high temperature and ABS like materials, Objet s inkjet based 3D printing technology now fills much of the remaining functional gap by providing an ABS level standard of engineering plastics simulation for functional testing, comparable to the materials used in both Fused Deposition Modeling and Stereolithography 3D printing. The 3D world in the coming years will move to increasingly resemble the 2D printing world. The next step in the evolution of 3D printing will see more and more rapid prototyping tasks for form, fit and function testing performed at the design and engineering office and desktop levels. There again, inkjet based 3D printing led by Objet is paving the way, providing the demanded levels of print quality and material properties. With such a technology at their fingertips, product designers and engineers can now make light work of prototyping cycles that used to take weeks or even months and that fared poorly in real world representation. With inkjet based 3D printing the result is a more instructive and efficient prototyping process and at the end of the day, a better end product, more quickly delivered to market. 8

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