Posted by Ernesto Hernandez on December 09, 2015 at 22:46:40:
In Reply to: Re: differential constant posted by Dan McEachern on December 04, 2015 at 01:39:09:
the differential constant is as fallow
.352459 *diametral pitch * sine of helix angle/ starts of the hob = ratio.
search this ratio in the pfauter change gear ratio book
is all you need good luck Ernesto H