Breguet Equal Segment Self-Winding Stop-Work
Breguet's stop-work uses barrel wheels that are not cut equally. Watch No. 28 has 4 sections of about 70 degrees and 1 section of about 80 degrees; a section consists of a segment of the barrel wheel and its adjacent slot. And the other watch has 4 sections of about 67 degrees and 1 section of about 92 degrees.
What happens if all the sections are the same size, 72 degrees? The following animations were created by modifying the barrel wheels using Photoshop.
The third animation was created by calculating the theoretically correct distance between the centers of the arbor and barrel wheels and and using that distance instead of the actual distance in the watch.