CHOICES MATURE PROTOTYPE INSIDE P Controls & Sensors. 18 Prototyping. 22 Electronics. 30 Motors

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1 October 2010 REACHING OEM DESIGN ENGINEERS ACROSS CONSUMER AND COMMERCIAL MARKETS WORLDWIDE PROTOTYPE CHOICES MATURE P. 18 INSIDE 14 Controls & Sensors 30 Motors ap 22 Electronics pl F ia o on nce ap Tw DE ln itt S cd er IG sg! N n 18 Prototyping

2 PROTOTYPING WHICH RP MATERIAL IS BEST? Choosing the most appropriate prototype process is essential and can help manufacturers save money. Materials for additive fabrication have been evolving over the past 20 years. In the beginning of rapid prototyping (RP), just getting a part out of the machine that resembled the design was amazing. Companies were not so concerned that the part had a rough finish and the material was as brittle as an egg. Early adopters shed many tears when they dropped their model on a table and it exploded like glass. Sadly, that piece of glass had cost thousands of dollars to make. While the primary processes of additive fabrication have not changed greatly over the years, the intense focus on the materials has allowed for this area to develop into a fairly mature offering of choices for the user. What makes this a bit more complicated is that the technology path of each RP process is unique, including stereolithography (SLA), selective laser sintering (SLS), fused deposition modeling (FDM) and polyjet. Each has its own development path since their technologies are so different, and it can be very difficult to determine which material to use and why. The typical behavior for a design engineer that has some experience with a particular technology, such as fused deposition modeling (FDM), is to really focus on the material options of that technology. While this approach works, it would be like a consumer looking to buy a mode of transportation who only evaluates trucks for their transportation needs, rather than considering the wide variety of options: trucks, cars, motorcycles, bicycles, skateboards, etc. There is still not a clear-cut approach for engineers to select the right process and material for an application. Even with expert consultation, guidance is typically skewed to the expertise of the consulting salesperson or the processes the company has to offer. However, there are some high-level guidelines that may help get an engineer started down the right path for parts. Keep in mind that the main areas of consideration include material by dr. ronald l. hollis Dr. Ronald L. Hollis is president & CEO of Quickparts.com Inc., Atlanta. SLA SLS FDM PolyJet Strength Medium High High Medium Surface Finish Smooth Grainy Coarse Smooth Speed Of Build Fast Moderate Slow Fast Heat Resistance Low High Medium Low Each rapid prototyping process has different strengths and weaknesses. It is best to have help in trying to select which process best works for your application. Source: Quickparts 18 appliancedesign October 2010 For more information on suppliers in this issue, take the at

3 PROTOTYPING Mechanical Properties Strength Modulus Elongation at Break Flexural Strength Flexural Modulus Izod Impact -Notched Heat Deflection Temp Test Method ASTM D790 ASTM D790 ASTM D256 ASTM D648 Prototyping Process Units % (ft-lb)/in F SLA ABS-Like - White (Somos 18420) 6,100-6, , , % 9,700-10, , , SLS Nylon (Duraform PA) 6, ,000 14% N/A 201, FDM ABS 3, ,000 6% 6, , Polyjet Hi Res Rigid VeroWhite 7,200 N/A 15-25% 10, , This chart compares the standard material properties for one commonly used material in each of the four primary rapid prototyping processes. Source: Quickparts properties, application and economics. Material Properties Typically, a designer or engineer will understand that his product will operate in some environment and have expectations of the materials being used. When buying a prototype, ideally engineers would love for it to represent the end-use material to get a full assessment of the product but unless the engineer is going to use an additive fabrication strategy for the manufacture of the product, this will not be possible and the engineer will be forced to select a representative material for the parts. With RP materials, this can be very tricky since the data is always vague and will have the caveats that the data presented from the appliancedesign October

4 PROTOTYPING testing samples, which may not be applicable for a specific product s geometries. Also, most of the material property data for the RP materials are produced by the material manufacturer with little independent assessment. The best way to apply the data is as a general representation of the properties and not as a hard fact. Application The next area to consider for a material choice is the application of the prototypes an engineer is going to develop. If you will be passing the parts around to your team and doing some minor fit and form assessments, then the material properties may be less important than if the application requires bolting the part to an engine and letting it run. If the need for the prototype is to fully represent the final designed part, due diligence will dictate that the engineer assess all manufacturing processes to get the part built. It may be that a non-rp method will be best so that the user can get the part that will really operate in the application of the prototype. Help in deciding the right process for the part is where getting great sales consultation will pay off without blowing the development budget. The right consultation can make a world of difference in selecting the correct rapid prototyping process for a part. As one can imagine, if someone goes to a wood worker for a solution to a problem, most likely the proposed solution will involve some type of wood. The same holds true for rapid prototyping. With such a wide variety of materials out there for each application, it is best to receive an unbiased opinion of what process would provide the best application. The processes include: Stereolithography (SLA). This rapid prototyping process uses a vat of liquid UV-curable photopolymer resin and a UV laser to build parts one layer at a time. SLA rapid prototyping is an ideal process for concept models, master patterns and tradeshow models. PolyJet. PolyJet processes jet photopolymer materials in ultra-thin layers (16μ) onto a build tray layer by layer until the part is completed. Each photopolymer layer is cured by UV light immediately after it is jetted. PolyJet rapid prototyping is ideal for concept models, master patterns and tradeshow models. Selective Laser Sintering (SLS). SLS is a rapid prototyping process that uses a highpowered laser to fuse small particles of powder to build parts one layer at a time. SLS rapid prototyping is a great process for functional Stereolithography (SLA) uses a vat of liquid UV-curable photopolymer resin and a UV laser to build parts one layer at a time. Photo: Quickparts With such a wide variety of materials out there for each application, it is best to receive an unbiased opinion of what process would provide the best application. Selective laser sintering (SLS) fuses small particles of powder with a high-powered laser to build parts. Photo: Quickparts 20 appliancedesign October 2010 For more information on suppliers in this issue, take the at

5 Fused deposition modeling (FDM) is a rapid prototyping process that uses a plastic filament of material supplied to an extrusion nozzle. The nozzle is heated to melt the material and can be moved in both horizontal and vertical directions. Photo: Quickparts testing and for low-volume manufacturing, such as in the aerospace industry. Fused Deposition Modeling (FDM). This rapid prototyping process uses a plastic filament of material supplied to an extrusion nozzle. The nozzle is heated to melt the material and can be moved in both horizontal and vertical directions. FDM rapid prototyping also is a good process for functional testing and for low-volume manufacturing. It is especially helpful since the materials used are actual ABS and polycarbonate. Economics PROTOTYPING Product development can be an expensive journey for many companies. The procurement of the prototypes is essential for the design process but can be a real black hole if the wrong process, materials or applications are used. Today, designers have many great options to produce prototypes that can work for them. With a little research, thinking and support, the designer can find what is needed for the prototypes at that time. For example, if it is a concept model to pass around, then a low-cost 3-D printed model may be the best option. When a real production-quality part is required, then a low-volume injection mold may be required that will shoot the part from the end-use thermoplastic. It s the designer s responsibility to understand the purpose of the prototypes and the right way to invest the budget. Think of it this way: Of course, a man could drive his truck one block to buy a newspaper, but a nice bike ride may suffice. For more information, visit: or Our pumps for more efficiency! Give free rein to your ideas. Your requirements are our drive and have been for more than 60 years. HANNING's sophisticated and customized pumps and drive systems in synchronous technology result from a close contact with our worldwide customers. If you wish highest efficiency and lowest ppm rates come to HANNING. Challenge us! HANNING ELEKTRO-WERKE GmbH & Co. KG Holter Straße 90 D Oerlinghausen Tel +49 (5202) Fax +49 (5202) info@hanning-hew.com appliancedesign October