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Nypro : 3D QuickFill Nypro Inc., the leading global custom injection molder operates 24 molding companies in 10 countries. The company's eight moldmaking shops make it one of the world's largest tooling companies. Its Corvallis, OR facility provides customers with the latest machinery and systems in molding technology anywhere in the world. As a truly customer-directed enterprise, Nypro Oregon cultivates a culture of quality and service with their customers, offering flexible and innovative solutions to their molding requirements. This emphasis on partnership between customer and molder epitomizes the business environment at Nypro Oregon. Bill Cole, Nypro's engineering manager, offers some insight about how his team locally expedites new quotes and acquires new business. "We use a process called 'AIM' – access, initiate, and manufacture. We access information provided by customers, initiate processes to determine if parts are manufacturable, and ultimately make the components. Our engineering group uses C-MOLD and SolidWorks to determine if the parts are moldable, and if we can generate thin-walled parts to obtain higher-performance and reduce costs. The technologies also help us identify issues based on volume. For instance, we can determine if we can use a higher cavitation in order to reduce piece-part cost. The selection of materials is very important at this stage to optimize performance characteristics as identified by the customer." C-MOLD and SolidWorks Cole says he's been a strong advocate of desktop engineering for a long time. "In the past, desktop engineering was very difficult to provide to every engineer because of costs and the inefficiencies of the programs. Integrated systems were few and far between. The introduction of SolidWorks and its Gold Partners such as C-MOLD allows us to offer desktop engineering to every engineer at Nypro." The combination of C-MOLD's 3D QuickFill and SolidWorks allows Cole and his team to translate a design into a solid model. "We can make changes very quickly in SolidWorks," Cole adds. "The software allows us to point and click and run a quick evaluation for mold flow, identify areas of concern, and return back into the model to make changes to wall thickness, geometry, add radiuses to obtain better performance flow in 3D QuickFill." Fast, accurate quotes Cole believes the Windows-NT environment facilitates desktop engineering. Consider 3D QuickFill's reporting mechanism. Once users complete a model, a report presentation is included in every quote package. The information contained in the booklet proves that Nypro evaluated each component of the quote. One of the most important components of 3D QuickFill's reporting mechanism is an explanation of how Nypro derives its steel selection and gate locations. "When we download a model into 3D QuickFill and begin to consider gate locations, the first rule of thumb is to always follow the thick-to-thin approach to obtain optimal performance characteristics," says Cole. "While we assess gate locations, we can move part features, alternate between 3D QuickFill and SolidWorks, and identify venting issues that might be hard to visualize in blind pockets. Using 3D QuickFill, we can modify gate locations to move them away from blind pockets to eliminate negative elements such as erosions and no-fills." 3D QuickFill's reporting mechanism can also be used for design specifications. Helpful information such as tonnage, based on a single cavity is provided. The tool also calculates part weight based on the specific material being used to generate parts and press cycle estimates. This information, together with cost and overhead, can be compiled to generate an accurate quote very quickly. Cole appreciates the major improvements to the latest version of 3D QuickFill's Cost Cruncher technology. "For quick, one-day estimates, the technology provides all the components necessary to make a successful quote, including identifying all the costs associated with the product and get it back to the customer very quickly," says Cole. Unusual project using 3D QuickFill Nypro is currently developing a new, state-of-the-art, internally worn medical device. It is made of a polycarbonate urethane blend—a tricky material to mold. "Our cold runner-based pre-production tools are a family tool of three different sizes," reports Cole. "We had extreme issues with the product because the material has a tendency to worm and have large flow lines. We are required to mold the parts because of the high accuracy associated with the performance characteristics of this plastic component. We needed to control the polymer flow and control the performance characteristics on a single cavity. That's where 3D QuickFill was very helpful. "First, I used the software to identify a 'play' area of the geometry—one area of the part to determine how to get the material flow to the edge. One of the issues I had with this particular part is that the urethane polycarbonate blend has a tendency to want to snap and gas significantly at the end of the fill. This scenario is totally unacceptable since this material costs $60 per pound and our scrap rate was about 20%. "In complement with SolidWorks, I used the 'play' area geometry as I identified and examined thin membranes down inside a diameter that I intended to machine out. I worked for approximately three hours moving back and forth between SolidWorks and 3D QuickFill changing thickness and membrane at the centerline of this round component. As a result, I was able to completely balance the flow of the material using 3D QuickFill. The software enabled me to have a live, graphic presentation by using a melt-front advancement to keep modifying geometry slightly in order to move the end of fill to the outside of the part. I needed perimeter venting at parting lines. I printed a series of them that showed from 25 per cent to 95 per cent fill. At 95 per cent fill, at the current location and the geometry of the membrane that the gate will go into, I obtained exactly what I needed." Prior to using 3D QuickFill, obtaining these types of results was very tedious and cumbersome. Using 3D QuickFill allows users to quickly and accurately perform the calculations on the desktop. For Cole's medical device project, there were no written specifications for the polycarbonate urethane blend material. "3D QuickFill allows users to customize specific materials. For example, I can select pelathane from the list of materials, adjust the flow characteristics, maximum injection pressure, and adjust mold components (temperature and melt). I can point and click and rerun the model to visualize what opportunities exist to increase my performance," notes Cole. Cole also appreciates that 3D QuickFill addresses sinks. For the medical device project, the contour of the radius had to be very flat. For the first gate selection and thin membrane that Cole incorporated into the CAD model, 3D QuickFill predicted sinks as high as 17 thousandths. For some jobs, that rate may not cause a problem, however, for this project, it did. "This prediction capability is truly a trouble-shooting marvel," notes Cole. "There are no calculations out there that predict where problems will crop up. Most experts in this industry rely on experience." As a result, Cole changed the membrane at the centerline of the part to obtain very accurate symmetry. "In this case, notes Cole, "I went against my better judgment and proceeded going from thin-to-thick based on the performance characteristics of this particular material. What I discovered was, by also increasing the pressure within normal guidelines of the injection molding machine and the tool, I was able to reduce the sink measurement to four tenths on that particular surface geometry. That's very exciting because before we cut any steel, I know the absolute best performance characteristics, gate locations, and part geometry before we begin to design the tool. In our fast time-to-market industry, that capability will help us turn better products around faster and at a lower cost." Author: Laura Carrabine |