Swiss engineer and Thingiverse user Christoph Laimer has successfully fabricated a working clock with a tourbillon made entirely from 3D printed gears, mechanisms and components. The parts were printed on an Ultimaker 2 desktop 3D printer with the case being printed in PETG while all of the internal gears and mechanisms were printed with standard PLA. Even the clock's spring was 3D printed and it will run the clock for 35 minutes before it will need to be wound up again. You can read more about this amazing 3D printing project over on