Filament Winding Resin Bath
Team: Tate Adams, James Alder, Daegan Mansouri and Crystal Tingle
Project Description
This project focuses on redesigning a filament winding resin bath to improve control of resin content and fiber wet-out in Composite Overwrapped Pressure Vessels (COPVs). The previous system exhibits misalignment between the drum and doctor blade due to excess degrees of freedom, resulting in inconsistent resin film thickness and variability in fiber volume fraction.
Design Requirements
- Consistent and repeatable gap control (±0.001 in)
- Uniform tow wet-out
- Compatible with existing filament winding systems
- Ease of cleaning
Constraints
- All resin-contact components compatible with acetone
- Component size compatible with cleaning process
- Drum weight < 50 lbs
- Maintain tow separation throughout wind
Static Rollers
Maintains consistent tow alignment, tension, and exit angle from the resin bath
Reversible Combs
Guides and separates fiber tows while allowing quick reconfiguration for different tow paths
HDPE Side walls
Determines bath configuration
Dynamic Rollers
Rotates with fiber motion to reduce friction and help maintain uniform tension at entrance of the system
Drum Movement Mechanism
FUNCTION
Regulates resin film thickness through controlled drum-to-blade gap, directly influencing fiber volume fraction.
Ensures uniform and repeatable wet-out across the full tow path.
PRECISION
Precision Lead Screw allows for fine, low backlash linear motion
Bearing housing constrains drum ends for stable alignment relative to the doctor blade
SYNCING
Timing belt links motion between both sides for equal movement
Maintains a uniform gap and prevents drum misalignment
Drum and Doctor Blade
Resin application to the fiber is controlled here. The drum rotates through the resin bath, carrying a thin film of resin to the fiber tows as they get pulled through. Adjusting this gap directly controls resin content and fiber volume fraction in a COPV, making it the primary mechanism for achieving consistent and repeatable wet-out.
Constraining the doctor blade and controlling the position of the drum with the Drum Movement Mechanism reduces variation in gap size along the entire length of the doctor blade.
Bevel Gear Box
Converts rotational input 90° with a 1:1 ratio for ergonomic hand crank operation
Pulley
Transmits rotational motion to synchronize both sides of the adjustment system
Bearing and Housing
Supports drum and transfers load while maintaining alignment with the adjustment system
Hand Crank
Provides manual input with increased mechanical advantage for fine, controlled adjustment
Lead Screw and Linear Slides
Converts rotation into 0.025” linear motion per turn while constraining movement for precise gap control
Performance Review
The design improves performance by reducing unnecessary degrees of freedom between the drum and doctor blade, resulting in more consistent gap control and resin film thickness.
Evaluation shows that precise adjustment of the drum position directly controls resin content, improving repeatability of fiber volume fraction. The guided tow path minimizes fiber overlap and ensures uniform wet-out.
Compared to the existing design, this system reduces alignment variability and improves consistency in resin application while maintaining ease of operation and cleaning.
Conclusion
The redesigned resin bath meets the design requirements of precise gap control, consistent fiber wet-out, and ease of cleaning while satisfying all system constraints. By reducing excess degrees of freedom and introducing synchronized motion, the design improves alignment and repeatability compared to the previous system. These improvements directly contribute to more uniform resin film thickness and more consistent fiber volume fraction.
Lessons Learned
A key lesson learned was the importance of constraint-based design in controlling alignment. Rather than relying on manual adjustments, properly constraining motion and eliminating unnecessary degrees of freedom will prove essential for achieving consistent and repeatable performance.
Future Work
Future work includes experimental validation of resin content as a function of gap distance and integration of motorized control for automated and programmable adjustment. Additional improvements may include enhanced guarding, sensing, and process monitoring to further increase reliability and usability.
Acknoledgements
The team would like to thank our professor, Jackson Graham, for his guidance and support throughout the design process, including feedback on the project.
We also acknowledge our industry sponsor, HyPerComp Engineering Inc., for providing project direction, technical insight, and real-world context that helped shape the design requirements and ensure relevance to industry applications.
Additional thanks to the Utah State University College of Engineering for providing the resources, facilities, and academic support necessary to complete this project.