Helix Angle relative to Pitch of a Spiral 1

[williedawg]

I know this is easier than what I'm making it....

When constructing a Spiral and the starting position is known, what is the PITCH value you'd enter to get
a common 45deg tooth gear such as for a matched set of right-angle gears.
Tried 8, which doesnt look too bad, but I know it's gotta be something definite.

The gear blank is 1.942 dia; How is the PITCH value arrived at?

 

[williedawg]

after some deliberation, it dawned on me that the value for PITCH is the blank O.D. x Pi for a 45deg tooth. (1 to 1 ratio)... unless I'm missing something.

 

[RangerGirl]

Here is a list of equations that came from the machinery's handbook that I use for reference. Page three has equations for Sprial Bevel Gears.