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Barry Matties leads this engaging retrospective conversation with Dave Hillman, a Fellow, Materials and Process engineer at Collins Aerospace, who talks about mentorship, pandemic changes, and solder. “Soldering is soldering,” Dave says. “But how we do that keeps evolving in response to the new technologies and smaller packages.” What’s the key to his success and longevity? “Find your passion.” Here’s how he’s done it.
Barry Matties: Dave, you have been in the same position with the same company for nearly 40 years. That type of thing doesn’t even exist anymore.
Dave Hillman: I’ve been really privileged to be able to do so. We have a co-op program at Collins, and I’ve been able to mentor. We get four co-ops a year, two for spring/summer, and then two for summer/fall. About 150 kids to date. A lot of them now are industry colleagues, both in and outside Collins. It’s been fun to watch that transition, to watch them grow, to see the technology changing.
I think it’s interesting how my mentors have always talked about how big a shift it was from plated through-hole to surface mount and how that was revolutionary for the industry. Well, lead-free is doing the same thing. It’s challenging our material sets. What do you do? How do you get there? Collins is one of the few defense contractors that has been building lead-free for 10 years and it’s been very successful. I think the real trick is that we’re engineers. It’s a problem; go solve it.
Matties: Your expertise was in soldering, correct?
Hillman: Correct. I attended Iowa State University for my bachelor’s, then went back 10 or 15 years later for my master’s. I function as the soldering subject matter expert in terms of metallurgy, alloys and processes, troubleshooting, that sort of thing. It’s been a lot of fun. Our industry seems to like to replay the lessons of the past; gold embrittlement is probably this sexiest topic ever on the planet because we just keep talking about it.
Matties: One of the things that we hear constantly is that field defects primarily come down to the solder and solder joints. As an expert, would you validate that statement?
Hillman: I do. If you don’t want defects, it comes down to making sure a design is producible. For instance, why would you have three different product design teams that are using the same part with three different footprints? You don’t need three footprints. You need one footprint because for the manufacturing guys that will be efficiency on their end and uniformity in the solder joints.
As my friend Doug Pauls would say, you can design the most beautiful thing on the planet, but if you can’t build it, what good is it? This industry no longer designs something, then throws it over the wall. Nowadays, the design teams and the manufacturing teams are very much connected.
Matties: With the soldering process, there are a lot of ways it can go wrong.
Hillman: I think it’s interesting that we had this huge drive for “just in time,” “no WIP,” and “keep your inventory low.” Then COVID hits and suddenly we don’t have anything in stock. We have no security backup. That “just in time” philosophy works when things are coming together as planned. I think we all underrated how critical it is to a process.
Matties: We’re seeing a new trend in how we’re melting solder as opposed to the traditional reflow processes. How do you view these new technologies in terms of market acceptability and performance?
Hillman: I remember my mentors telling me early in my career, “Here’s the wave solder machine, but don’t pay much attention to it. It’ll be gone in about five, six years. We’re not using it very much.” Yet, we still have wave solder. Our soldering processes have evolved to deliver what’s needed.
To read this entire conversation, which appeared in the March 2022 issue of SMT007 Magazine, click here.