The NC State Memorial Bell Tower stands as a symbol of pride and tradition for the Wolfpack community. A figure of unity and remembrance, it serves as a gathering point for celebrations, reflections, and inspiration for students and alumni. Recently, an issue with the clock mechanism has disrupted its functionality. A worn gear has started to cause significant discrepancies in timekeeping on one of the clock faces. This challenge prompted David Bliss, a Master of Engineering Management (MEM) student and the Bell Tower Keeper, to take action.
Bliss first noticed the problem when the north-facing clock began losing time dramatically, falling behind by hours rather than minutes. “The clocks lose about one minute a week,” Bliss explained. He resets them every two weeks to keep the time close to accurate, but he noticed that the lost time was increasing. One time, the north face was off by about 15 minutes instead of two minutes. After resetting the clocks, he found the clock face to be off by nearly four hours. Bliss discovered the gears on the face were worn and slipping, unable to keep time.
Seeking a solution, Bliss reached out to Harvey West, an Associate Research Professor in the Industrial and Systems Engineering Department (ISE) and Manager for Material Testing and Characterization in the Center for Additive Manufacturing and Logistics (CAMAL). “David found my name and reached out to see if we could help,” West said. “We’ve worked on projects before where parts were no longer manufactured. Our process involves examining the worn part, identifying the original dimensions, and machining a precise replacement.”
Equipped with a portable X-ray fluorescence device, West accompanied Bliss to the Bell Tower to determine the composition of the existing gears. “Understanding the alloy composition of the piece is crucial,” West explained. “If you’re going to make new gears, the material must match or be better than the original.” The worn gears, played an important role in the clock’s functionality. To ensure even wear of all the gears, West explained that four versions of each part needed to be manufactured—one for each clock face of the Bell Tower.
CAMAL, known for its cutting-edge capabilities, will play a pivotal role in crafting the new gears using Wire EDM (Electrical Discharge Machining). This advanced technique ensures precision and durability, which is essential for the long-term functionality of the Bell Tower. Additionally, Bliss has been working to retrieve original blueprints from the IBM corporate archives, further aiding the restoration process by showing the original measurements of the Bell Tower gears.
The goal of this project is twofold: to restore the clock’s accuracy and preserve the tower’s historical integrity for future generations. Newly manufactured gears will restore all the clock faces to full functionality and generate replacement sets for when the clock faces fail again. “When we are digging into these systems, one thing we try to keep in mind is the historical pieces associated with the Bell Tower,” Bliss explained. Missing information is archived for future generations and older equipment is kept safe for future generations of the Wolfpack who may want them for museum pieces or other historical interests.
“There are a lot of people on campus that really love the university and its history, and they all seem to step up when needed to help with things like the clock gears or other such issues,” Bliss expressed. The team is now finalizing gear plans and double-checking measurements before CAMAL begins manufacturing. Once complete, the gears will be installed, restoring the Bell Tower to full functionality and preserving its place as an iconic NC State landmark.