(On the photo you can see the redrawn top corner)
On old Cremonese instruments, the edge doesn't have the same thickness everywhere. It is thickest at the 4 corners, then is is a bit lower in the "C"-bout and it is the lowest in top and bottom bouts.
In the first year, we just market the different edge thicknesses with the marking gauge, made a flat purfling platform and then made purflind and fluting and arching.
But, when making the fluting up to the edge, this phenomen appears automatically because the fluting is deeper in top and bottom bout than in the "C"-bout, and the fluting going up to notthing in the corner, makes it automatically the highest point.
I had to choose one gouge to do the whole fluting, and determine the edge thickness to start with.
I finally decided to use 3 gouges with the same curve but different widths (sweep 5) and determined 6 mm as edge hight. When the purfling was put in, and the edgework was done, I had a final edge thickness of 5,5 mm on the corner, 5 mm in "C"-bout and 4,5 mm in bottom bout. Which is exactly what I wanted!