A few minor changes were made to outer edges of blades.

Created helix, times 4, extending down 70 mm, for a section. (60 degrees)
Six sections would reach 360 degrees.
For blade cross section profile, did a two_rail_sweep to two helices. Repeated for other blade.

To Do: two interlocking pins and sockets, axis, top, bottom.

- Brian

ps Earlier, script ImportSTL was used to import the thingiverse .stl.
The 59,000plus triangles mostly imported, with some lost.
The very large file produced a moderately good looking rotor section, enough to check and get distances and angles.
Then deleted the .stl import. Too Big...