Not new but new to me at W&W - when I first looked at this movement, the nicely finished click spring jumped out at me. Not a lot of linear features in movements and this one was subtle and beautiful
They call it guilloche a main because it is done by hand-controlled machines. If you aren’t very, very careful with the pressure, the cutter will dig into the surface and ruin the pattern Roger Smith did a short series on guilloche on YouTube that’s great. “After a couples of hours, a slip here will