Space Dynamics Laboratory Foil Cutter Upgrade
Team: Regan Tracy, Zachary Wheeler, and Conner Simpson
Sponsor: Space Dynamics Lab
Upgrading Foil Cutter Efficiency for Thermal Strap Fabrication
This project upgraded SDL’s foil cutting system for thermal strap manufacturing by adding three modular subassemblies—the wedge, graduated shelf, and wagon wheel. These enhancements improved cutting accuracy, automated waste removal, and stabilized foil rolls, reducing operator input and material waste. The system maintained compatibility, met all constraints, and delivered ±0.10 in. cutting tolerance, 97% automation uptime, and zero foil damage—boosting throughput and reliability.
Requirements, Constraints, and Goals
| Requirements/Constraints/Goals | Target | Threshold | Predicted Performance | Actual Performance |
|---|---|---|---|---|
| The automated plastic backing removal system shall remove plastic backing without requiring user interaction for the specified amount of operation time | N/A | 90% | 95% | 97% |
| For every fifty 3-in. pyrolytic graphite sheets (PGS) foils cut, no more than the specified amount should be damaged or curled by the final deliverable | 3 foils | N/A | 4 foils | 0 foils |
| The following quantity of parts designed for the final deliverable that are not part of the previous build should be backwards compatible with the previous build and not require part substitution | 100% | N/A | 100% | 100% |
| The following quantity of parts designed for the final deliverable that are not part of the previous build should be manufactured utilizing existing, in-house manufacturing technology found at SDL | 100% | N/A | 100% | 100% |
Before
After
Project Outline: The upgraded foil cutter project at the Space Dynamics Laboratory focused on improving an existing cutting system used in the production of thermal straps. The primary goals were to enhance cutting precision, automate the removal of plastic backing from PGS (Pyrolytic Graphite Sheet) foil, and reduce the occurrence of foil tangling and damage. The project involved designing and integrating several new subassemblies—including a passive wedge for backing separation, a graduated shelf for adjustable foil catching, and a wagon wheel system to prevent foil roll slippage. Each component was designed for easy integration into the existing system while meeting strict constraints on space, power consumption, and manufacturing feasibility.
The final system achieved all target performance metrics, including a cutting tolerance of +0.015/-0.011 inches, 97% plastic backing removal efficiency, and no foil damage over 50 test cuts. Despite a conservative budget threshold of $15,000, the total project cost came in at $13,990. The design remained compatible with the original system and proved manufacturable entirely in-house. Overall, the upgrades not only improved operational reliability and repeatability but also streamlined the manufacturing process for SDL’s high-precision thermal components.
Conclusion
Testing
- Backing Removal System
During the testing phase, it was found that the system required only 1 minute of user interaction over a 30-minute cutting period, equating to 96.67% of the time operating without user intervention. This result far exceeds the target of 90%, confirming that the design meets the constraint.
- Foil Damage
The upgraded foil cutter was tested by cutting fifty 3-inch pyrolytic graphite sheets (PGS). After inspecting the foils, it was found that none of the foils were damaged or curled, well below the threshold of 3 damaged foils out of 50. This demonstrates that the design satisfies the constraint of minimal foil damage.
- Backwards Compatibility
The new parts were successfully attached to the original foil cutter without modifications, and the foil cutter operated as intended. This confirms that the new parts are fully backwards compatible, satisfying the constraint.
- In-House Manufacturing
The parts designed for the upgraded foil cutter were manufactured in-house using SDL’s 3D printing and machine shop capabilities, meeting the constraint of using existing in-house manufacturing methods.
Lessons Learned
3D printing was central to the project, with built-in supports key to producing complex parts. Planning ahead, including buffer time, helped us manage delays from absences and holidays. Submitting machining requests early was crucial due to SDL’s internal priorities. Using multiple vendors sped up turnaround and strengthened supplier ties. Lastly, more electronics knowledge would’ve helped, as soldering and wiring proved challenging for our mechanically focused team.
Recommended Future Work
To improve future builds of the foil cutter, we recommend streamlining and standardizing the GUI software to ensure compatibility across different computer systems, preventing issues during IT hardware updates and minimizing the need for specialized electrical engineering support. Additionally, efforts should continue to address the static generated when peeling the plastic backing off the PGS foil, which hinders proper foil separation and can cause jams; optimizing this process would improve reliability. Finally, increasing the cutter's width to handle 6 to 8 foil rolls—up from the current 5—would significantly enhance production efficiency for the Space Dynamics Laboratory Thermal Straps team.
Acknowledgements
We would like to express our gratitude to Wyatt Olsen, Jackson Graham, and the Space Dynamics Laboratory for their support, mentorship, and guidance throughout the design and development process.