To find the radius of the rotor face one needs to know the relationship between
the radius of a circular arc, the length of the chord connecting its two ends,
and the deflection of the highest point or that arc from the center of the
chord. This latter quantity is called the sagitta, or sag for short.

http://liutaiomottola.com/formulae/sag.htm


The cord of the rotor is about  180 mm and the sagitta is 23 mm
so r is about 715.848 mm.


The OD of the phasing gear is about 109 mm.
The oil seal slot wall is 1119 mm ID.

Here is what I have on the cast iron rotor so far if someone wants to
give doing  a 3D a try.

Since titanium is stronger than cast iron perhaps one could cut
the thickness for some of the wall sections.

Paul Lamar

Paul
I always thought the rotor sides were made by overlapping 3 circles, but
the maths in the books by that Japanese gentlemen, Kenichi Yamamoto, are a
bit beyond me at first glance.
George (down under)

You may be right. That may be the way it is machined.

Paul Lamar