As Invivo Corporation began to finalize the design of its innovative Luminescence Breast Coil System and Biopsy Device (LBS), Dean Walters, Invivo’s Lead Engineer for the project, began consulting with the engineers of Nicolet Plastics.
“We’ve worked with Nicolet Plastics for 25 years,” notes Walters, “and experience has shown that it’s best to involve their engineers early in the process because they use their expertise with plastics to optimize product designs, the mold and tooling processes and even materials selection to give us more cost-effective, high-quality options.”
The design of Invivo’s LBS — a device that provides illumination, superior imaging, immobilization and needle guidance for interventional biopsies — was particularly challenging. Not only would the disposable device need to meet the highest sterility standards, it had to have exceptional mechanical strength in order to provide stability, and had to be composed of both biocompatible and flame retardant materials that wouldn’t image during an MRI scan. This meant improving designs with product development engineering.
“Some components were designed ahead of time, but Nicolet Plastics reviewed all our specs,” explains Walters.
“It’s part of every process we do for a client,” adds Nicolet Plastics’ Project Manager for the BBD program. “We ask our clients’ engineers a series of questions about their product requirements to see what alternative materials and production avenues are open to us. We want to make the process as cost effective as possible, without minimizing the quality of the products — it’s a powerful combination of engineering and product development. The engineers of our clients may not be well-versed in plastics, so our expertise helps them discover alternative designs, materials and production methods they may not be aware of.”
Walters agrees, “Some of the LBS’s more complex tools had side actions, and we had to work with Nicolet Plastics to determine directions of pull. We couldn’t have finished the design without their input.”
One of the first cost savings implemented was the result of Nicolet Plastics engineers partnering with Invivo engineers to change the radii of certain pieces, effectively reducing the tooling costs and increasing the structural integrity on several parts. Because Nicolet Plastics specializes in both custom injection tooling and molding, Invivo was able to take advantage of a special tooling program.
Nicolet Plastics developed a unique tooling program that provides customers with lower cost tooling and improved lead times. Because steel is available in house, work can start on the mold build quickly and often at prices that are normally associated with imported tools. Nicolet Plastics was able to produce the Invivo tooling faster and more efficiently than could have been done using conventional tooling methods. It’s all about quality efficiency: 49 parts were made using 24 tools.
Choosing quality materials.
“Materials selection was critical,” states Walters. “The materials we originally selected were not readily available and had long lead times — which isn’t good for rapid product launches. Nicolet Plastics found better materials options that cost less but were just as effective and performed the way we needed them to.
“At one point, we were struggling to find biocompatible material for a Fiducial Cap,” notes Walters. Nicolet Plastics engineers went to work looking for a clear, rubber material that wouldn’t image during an MRI. “Nicolet Plastics discovered the material in a short time and quickly provided us with sample materials,” adds Walters.
“Within a week, we had the tool built for the Cap and everything kept moving forward,” notes Nicolet Plastics’ project manager.
In another instance, Nicolet Plastics engineers assisted Invivo with the design of an LED Light Lens. “Invivo had a single part they wanted to mold that had to be water-clear transparent, chemically resistant and flame retardant because there are electrical components behind it,” explains Grobe. “A previous vendor had recommended a material to Invivo, but we knew it wouldn’t work because it is amber in color. After some research, we recommended using a copolyester material that is transparent and very chemically-resistant.”
Walters adds, “Invivo also suggested making the lens a two-piece design with the transparent copolyester on top and a flame retardant polycarbonate on the bottom. They bonded the pieces together with a bonding agent that did not image — and suddenly our problem was solved. Because of Nicolet Plastics’ excellent material selection, we had a biocompatible shell and the flame resistance we needed in very short time.”
Diligence on the front end, means saved time and costs on the back end.
Prior to production, Nicolet Plastics conducts mold flow analysis as part of the product development process. Mold flow analysis shows the last areas of the part to fill, how the material will orient within the mold and potential warpage and stress points.
Nicolet Plastics’ project manager explains, “We take a good look at the manufacturing process by using a mold flow analysis software that simulates the injection molding process — it helps us identify potential problems before we begin construction of the mold.”
Walters points out, “Nicolet Plastics helped us develop optimal gate location and size. We also identified stress areas and were able to increase radii in order to eliminate those stress points and perfect the tool before the final stages. Ultimately, the product development and mold flow analysis work we did with Nicolet Plastics in advance of production helped us get to market faster and to do so with less cost.
“In the medical field time is of the essence,” continues Walters. “Time-to-market is critical to being competitive. We pushed Nicolet Plastics to provide tools within a very aggressive timeline and they delivered samples in just six weeks.”
Walters credits that to several things — all part of the Total Product Solution™ of Nicolet Plastics, “Project management was exceptional and that’s key to a successful project. Someone was always available for support because they’re entirely dedicated to the project dedication — from the project manager, to engineers and floor support.”
Nicolet Plastics’ in-house custom injection molding and mold building capabilities were also key to meeting Invivo’s aggressive deadlines. Within Nicolet Plastics’ 41,000-square-foot production facility, it completes injection molding and overmolding operations, as well as secondary machining. They also house a substantial inventory of materials in order to quickly meet a client’s customized, deadline-driven order.
Nicolet Plastics has both a tool room and molding area in one building — that saves time. They are able to sample tools and complete the secondary machining, chemical bonding, insert installation and assembly on site.
“They do it all within a very short time — and they’re a great company to work with,“ Walters concludes.