Scientific molding methods help to close the gap from tribal knowledge and individual experience at the press to predictable outcomes and clear actions for tooling adjustments and press control settings, says Robert Bodor, Chief Technology Officer, Proto Labs (Maple Plain, MN). He will address the many benefits of this approach at the forthcoming co-located MD&M Chicago and PLASTEC Midwest event in Schaumburg, IL, during a conference session devoted to developments in materials, sterilization capabilities, and quality control.
During the Thursday afternoon session, Bodor will explore common issues experienced in injection molding, and present some tools that can be used to solve them. Much of the focus will be on part design and material choice, he adds. "At Proto Labs, we examine the material properties and shrink rate of plastics, and use an internal flow analysis program called ProtoFlow that illustrates injection pressure and fill temperatures. If there are issues, we can make adjustments before the mold is milled and parts are molded," says Bodor.
Scientific molding techniques can help to shift the focus from the mold, which is typical of traditional tool making, to the plastic that will fill the mold, he explains. "Of course, both must be considered, but scientific molding takes into account the characteristics of the plastic: its temperature, the pressure at which it's injected, how it flows the through the mold, and the speed at which the plastic cools," says Bodor.
Relying on the expertise of a seasoned operator may get you the same result as scientific molding principles, Bodor acknowledges, but a data-driven approach will get you there that much faster. "In scientific molding, you develop a standard approach that yields predictable results to achieve repeatable parts. Usually this is about developing an optimized process to produce consistent parts with speed. By using scientific molding, you have essentially created a work instruction for your process engineers," he explains. The technology "creates predictable outcomes and clear actions for tooling adjustments and press control settings, and it can also help create good results for complex or hard-to-mold parts."
Bodor will expand on these and related themes at the MD&M Chicago and PLASTEC Midwest conference on Thursday, Oct. 16. He will be joined by Dennis D. Jamiolkowski, Distinguished Research Fellow, Ethicon (Somerville, NJ), who will be speaking on bioresorbable plastics, and Stephen Spiegelberg, PhD, President, Cambridge Polymer Group (Boston, MA), who will explore failure analysis of medical polymers. Read "Deep dive into medical polymers at MD&M Chicago" for more information about this session.