What about the commands FlowAlongSurface and than Orient (with scale) and Loft (natural) to get a bevel gear? The FlowAlongSrf command makes it possible to turn all the teeth of the spurgear curves. See attached rhino file. In the layers I descripe the steps.
fig 1 help surfaces for FlowAlongSrf.
fig 2 FlowAlongSurface. ( Copy=Yes Rigid=No Plane ConstrainNormal=No AutoAdjust=Yes PreserveStructure=No )
Fig 3 Orient with scale
Fig 4 loft (natural)
Fig 5 create closing surfaces (cones and planes)
Fig 6 Use the command CreateSolid (delete input: No)
Bevel Gears by FlowAlongSrf.3dm (9.4 MB)
The results looks nice, but is this as good as the official way?
Cheers,
Bas