Success Stories

CSS worked with Aragon Surgical to significantly reduce its costs by converting a fully machined jaw housing for a laparoscopic surgical device to a stamped part with machined features. Brandon Loudermilk, Aragon Surgical's senior research and development engineer, explained that the company was looking to reduce the overall cost of its previously released laparoscopic surgical device by decreasing costs on as many parts as possible. The jaw housing was one of the higher priced parts for Aragon, and the company also faced challenges with receiving sufficient parts from its existing supplier.

Engineers at CSS began the process by examining at the part and discussing ways that it could be stamped instead of machined from a solid tube. "When we started, I thought there was no way anyone could stamp this part to be perfectly round and make it function properly," said Loudermilk. CSS engineers then engaged in conversations with Aragon and went through numerous steps to arrive at the most important features on the part and determine how it could be stamped within the necessary tolerances. In a few short weeks, they came to an agreement and were able to begin working on production tooling.

CSS showed Aragon a lock barrel for a high end commercial door lock that was similar in many ways to the jaw housing. "When I saw how they could produce that part, how round it was and how good the finish was, it made me consider talking to them more about stamping this part," Loudermilk affirmed. Engineers at CSS went over the Aragon part print with a fine-toothed comb, adjusting the 3-dimensional CAD model and marking up the original drawing with their initial ideas. The groups discussed the tight dimensions, stepping through each feature to see if they could hold the tolerances. They examined the mating parts to see what the critical features were and how the mating parts interacted, discussing which features were critical and agreeing on which other features could be machined out, and how the part would have to be aligned.

The Aragon Surgical part requires a unique rotary head used on milling the portion of the part that gets machined after it is stamped. After the part is formed, it goes into the milling operation to finish mill certain surfaces that need a particular surface finish and accuracy. The tooling costs were significant, but the high per part savings made the investment worth it.

When the part was made as part of a tube, it was held to a tolerance of plus or minus 1/1000th of an inch. The stamped part is capable of plus or minus 2/1000th of an inch. Even though the tolerance is 1/1000th more, the part is fully functional in the design, at a significant savings. The startup firm was conservative with its capital, and went through numerous discussions to arrive at an agreement, which included amortizing the tool costs used to stamp the part.

"We paid up front for a certain quantity of parts, with the additional cost going towards paying for the tool costs. This enables us to get cheaper parts quickly, without putting out our capital up front. After the initial run was consumed, the tooling comes out of the piece price, making it that much more attractive and profitable." Loudermilk estimates that the initial run was 20-30 percent cheaper; when the tooling costs come out the new stamped jaw housing is 50-60 percent cheaper than the machined version, while still meeting all the design specifications.

Is raw material cost a main concern, or is tooling cost the largest issue? Getting this information up front is essential to develop a prototype or series of prototypes to meet their needs. With a brand new product, enough detail is needed to work out the best material to make a prototype that can be manufactured in a production scenario.

Tony Morefield, director of manufacturing and engineering services for Sunnyvale, CA-based Avantis Medical Systems, used the prototyping phase to great advantage to develop a cost effective spring for a catheter, which is fitted on the end to lock the part into the working channel of a scope. Avantis had experienced quality issues with its original supplier and was looking for a spring that would perform well in the instrument.

Spring tolerances were key; there were tight angles Avantis needed to be held for the spring to perform properly. As part of the research and development process for the part, CSS went through approximately 4 revisions where they tested slightly different angles and dimensions on the spring.

"Actually, it's interesting, but at first I didn't even realize we were prototyping," says Morefield. "We received feedback from the original drawings that the engineers were not comfortable they could manufacture the part as designed. We revised the drawings live on conference calls and discussed the design to see where we had leeway as far as changing tolerances. This method was great for coming to an agreement quickly on what the next revision would look like."

From CSS' perspective, the Avantis process was different than many because Avantis came in with a design whose tolerances and bend angles made it extremely difficult to manufacture. Engineers made a few suggestions on the bend angles that connect two coiled sections of the spring. Opening up some tolerances to make the part manufacturable and supplying a prototype to try it out worked well.

The result of the prototyping effort has been successful, says Morefield. "We have been through a lot of benchtop testing and have used the instrument on about 100 patients. We are now in the midst of a full commercial launch."

Value engineering helps our customers design parts that are within a tight tolerance and yet very manufacturable and consistent in the long run. It is most effective when the engineer has familiarity with a customer's product range and can take what they've learned in the past and apply it to new products.

For example, CSS has been working closely with Springfield, MA-based firearms manufacturer Smith & Wesson for more than 40 years, providing prototyping, high-speed progressive die stamping, and short-run die stamping on a variety of parts for numerous models of Smith & Wesson firearms.

One example where fast track value engineering helped Smith & Wesson was the development of Smith & Wesson's BODYGUARD® series, the first personal protection models with integrated lasers. Lightweight, simple to use, and featuring integrated laser sights, Smith & Wesson's goal was to provide the most state-of-the-art, concealable and accurate personal protection possible. The company needed to solve a variety of design and manufacturing challenges and was under time pressure to be able to launch the models with a splash at the Shooting, Hunting, Outdoor Trade Show and Conference (SHOT Show).

As the Vice President of New Product Development at Smith & Wesson tells it: "One of the most important things we look for is value engineering and value analysis to help us reduce costs, and for this project, CSS provided us with virtually a one-stop-shop for very fast feedback that helped us design the models for manufacturability."

She adds, "We are under considerable cost pressures and appreciate suppliers who actually look for opportunities to keep costs as low as possible. CSS utilizes their extensive experience to enhance every new project."

CSS makes the internal stamped grip frame assembly, a large part that holds the trigger bar and plays a significant part in how the trigger feels. CSS worked closely with Smith & Wesson, making several different prototypes and exploring multiple options. Design revisions were quickly incorporated for a variety of small components, which is especially important for critical interfaces. For example, in the BODYGUARD project, CSS produced the original stamping tool for the trigger bar and was quickly able to implement any changes identified during the design and testing process.