Lessons Learned in Converting Machined Parts to Stamped Parts

During the process of converting fully machined parts to stamped parts with machined features, the lessons learned by these two medical device manufacturers and a firearms manufacturer show how each step plays an important role in moving a part from concept to completion at the blazing speeds now considered normal.

The pace of product launch continues to pick up throughout every industry, responding to the speed at which information is exchanged and the perceived need to introduce the latest product revision to beat competitors. This is especially seen in medical instruments and firearms components, as well as parts produced for the consumer, automotive and electronic industries. Original equipment manufacturers are pushing the envelope to get from concept to production in the fastest possible time.

To meet OEMs’ need for this fast pace in the world of metal stamped parts and springs, engineering expertise is taking on an ever-more important role. Expertise in prototyping parts to test and prove design concepts, suggesting ways to reduce secondary operations to reduce cost, and providing value engineering consulting expertise,  are key engineering skills that ensure the success of projects. Behind it all is a foundation of communications and two-way dialogue that ensures that products meet customer requirements.

STARTING OFF ON THE RIGHT FOOT: INITIAL CUSTOMER CONTACT
The devil is in the details, so they say, and that’s what makes the initial customer contact phase so important. No matter what the industry, or the schedule requirements, each project should begin by establishing lines of communication to get an in-depth understanding of a customer’s design, objectives, and material requirements.

A discussion of part dimension tolerance is essential. Some tight tolerances may add significant cost, and may not be critical, while others may be achievable at no additional cost. Understanding the key dimensions and the most critical part tolerances is extremely valuable to both parties when developing the final part print. Familiarizing oneself with the product, including models and 3D drawings, and following that up by talking to the customer to get a clear idea of what is needed and identifying critical characteristics are the next important steps. These steps are followed by internal discussions to develop recommended options for design, tooling and production.

This initial phase set the scene for a successful project for Aragon Surgical, a Palo Alto, CA-based startup medical device firm that significantly reduced its costs by converting a fully machined part to a stamped part with machined features. Brandon Loudermilk, Aragon Surgical’s senior research and development engineer, explained that he was looking to reduce the overall cost of the firm’s previously released laparoscopic surgical device, and was given the task of finding ways to decrease 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; Farmington, CT) began the process by looking at the part and discussing ways it might 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.

Engineers at CSS then 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. Web-conferencing played a significant role, so the two groups could go back and forth quickly and remain on the same page. In just a few short weeks, they came to an agreement and were able to begin working on production tooling.