The usual way to do segmented turnings is to cut trapezoids and glue them up in a ring then stack the rings up to make the vessel. Typically, one cuts the same angle at both ends of the segment.
When doing reverse segments, one cuts one end to the appropriate angle, and leaves the other end at 90 degrees. The angled edge of the segment is oriented outwards rather than inwards. See my facebook post for an example of a ring being glued up:
OR = outside radius IR = inside radius
Width = OR - (.924* IR) Length = (.541*IR+Width)/.707
The segment length seems to come out a little long but that gives some fudge factor so that's fine.
What I'm looking for is the formula to enter the number of segments, the inside and outside diameter and for it to calculate the length of the long edge of the segment. Any math whiz out there that can clue me in?
Thanks...
...Kevin