Posted by Dimebag on January 02, 2017 at 04:34:59:
In Reply to: Re: No.104 Straight bevel generator - cutter designation letter posted by Dimebag on January 02, 2017 at 04:22:57:
"In the case of a 20° pressure angle system and a tilt angle of 20° for each cutter, the planes of the cutter disks would generate flank surfaces that consist of precise spherical involutes." - This seems to be untrue - a spherical involute can not be generated with a standard disc shaped tool in one pass, the shape would be octoid instead.
https://en.wikipedia.org/wiki/Bevel_gear#Geometry_of_a_Bevel_Gear