Gear to Gear clearance

[Bertho]

I saw an option in a tutorial to add a small offset to allow for machining tolerances but I can not find it.
I just bought Gerotic Thought

[ArtF]

Hi:

  In the past you added a small correction to the shaft distances, in G2 you make the tooth
a bit thinner by changing the tooth width from .5 ( 50%) to a lower number.. say .48(48%)
and youll find the connection gets looser. This is the way your supposed to do backlash
in gears, the distance bwteen them isnt supposed to change, its always supposed to be
the total of the two pitch radii

Art