erLay • Ultra-Portable CoreXY

At robotics tournaments, mechanisms inevitably take damage. Problems need to be solved with quick revisions between matches. I designed and built erLay, a compact CoreXY 3D printer engineered to pack into carry-on luggage and print functional replacement parts directly in the pit alley.

Mechanical & Firmware Highlights

• Carry-On Form Factor: Sized specifically to fit inside standard carry-on luggage while maintaining a practical build volume for robotics brackets, pulleys, and standoffs.
• Klipper & Input Shaping: Tuned with an ADXL345 accelerometer to measure frame resonance and compensate for vibration, allowing 10,000+ mm/s² accelerations without ringing artifacts.
• Wireless Control: Raspberry Pi Zero 2W hosts Klipper and the Mainsail web interface, allowing any team member to upload STLs and monitor prints over local Wi-Fi from pit laptops.

Results

• The printer was flown to Denver, Colorado and was demonstrated at Rocky Mountain RepRap Festival 2025.
• Documented full CAD models, configuration files, and assembly on GitHub.