TERRIER MOTORSPORT
DESIGN, 3D PRINTING, TESTING
2025-2026
INTRODUCTION
I am a manufacturing and CAD engineer on Terrier Motorsport, Boston University's FSAE team. I designed and fabricated a drag-reduced DC motor car chassis through a full design review cycle and built a pipe notching tool from scratch to replace a $50 commercial tool the team needed for tube joint fabrication.
DC MOTOR POWERED CAR
My initial CAD had obvious problems: the wheels were too thick, there was no axle, the motor mount had ugly geometry, and the assembly was put together wrong. I documented all of this at the CoDR. The revised design fixed the assembly, introduced a proper axle mount with 4.4mm tolerance, and replaced the flat trapezoid aero cover with a realistic car-profile shell that mounts directly to the chassis via interior lips.
For manufacturing, I intentionally split the work across processes: the chassis was designed for a laser cutter, the wheels for a manual lathe, the axle mount for the CNC mill, and the motor mount and aero cover for the 3D printer. The final CAD included gears for the motor-to-axle drivetrain and correct hole patterns for every component.
PIPE NOTCHING TOOL
I created a pipe notching tool to trace tube joint profiles before cutting, as the commercial version from Centurial Inc ran for $50+. I was tasked with reverse-engineering the tool for under $10 using a 3D printed body and 1/16" stainless steel TIG rods as the pins. The core engineering problem was fitting 32 pins into a body sized for 1" OD tube with enough friction to hold the mold. I worked through the geometry from first principles: the bore inner diameter came out to 26mm with 0.3mm clearance per side, the pinhole diameter to 1.75mm after print tolerance, and averaging the min and max pin center radii gave a PCD of 31mm. I verified the geometry on a PLA prototype before committing to the final print, then assembled by cutting all 32 pins to length and pressing them into the body.
