For more information visit booth #1467 at MD&M East
Farmington, CT - Connecticut Spring & Stamping ( CSS), a manufacturer of precision parts for the medical, aerospace, firearms and defense industries worldwide, announces that it helped Aragon Surgical, a Palo Alto, CA-based startup medical device firm, to significantly reduce its costs by converting a fully machined jaw housing for a laparoscopic surgical device to a stamped part with machined features.
CSS uses its metal stamping expertise in the medical device arena, which includes prototyping and high speed progressive die stamping from 30-300 tons, in-die tapping, reel to reel processes, modular die options and short run stamping. The company has supplied stampings for hand held surgical devices, endoscopic clip appliers, suturing devices, and staple removers. Drive channels, jaws, surgical staples, and titanium clips are some of the components produced for these assemblies.
According to Brandon Loudermilk, Aragon Surgical's senior research and development engineer, the company was looking to reduce the overall cost of the firm's previously released laparoscopic surgical device by decreasing costs on as many parts as possible. The jaw housing was one of the higher priced parts, making it a good candidate for alternatives. In addition, there were problems getting sufficient parts from the existing supplier.
At the initial contact with Aragon Surgical, engineers at Connecticut Spring & Stamping (CSS) began the process by looking at the part and discussing ways it might be stamped instead of machined from a solid tube. At first Aragon did not believe it would be possible to stamp the part to be perfectly round and still function properly. Engineers at CSS hosted several conversations and went through numerous steps to arrive at the most important features on the part and figure out how it could be stamped within the necessary tolerances. In just a few short weeks, they came to an agreement and were able to begin working on production tooling.
CSS engineers showed Aragon another piece they make, a lock barrel for a high end commercial door lock that was similar in many ways to the jaw housing. CSS engineers 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, looking at 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 The startup firm is 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. 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.
