Le_Forgeron <jgr### [at] freefr> wrote:

> the top part of a teeth must never be close to the bottom part of the opposite gear.
> IIRC, if top part (difference of radius between red and green) circle is 1, the
> bottom part (grey and red) should be 1.25.

Yes, I would agree that there needs to be more [any] clearance between the teeth
of one gear and the body of the other.   I'm progressing towards that.

> And unless you have a specially made gear, the perpendicular straight line to the
black line
> (which start at the red line ?) should be the line on which the teeth of each gear
get in contact
Right the gears ought to meet where the red circles are tangent, and "roll"
along a line that is tangent to both base circles - which makes it normal to
both involutes at that point.  I'm working on illustrating that.

> You are correct: you have a problem with the width of the tooth.

I'll look through that - I've probably seen 100 similar pages, but that doesn't
help me "put it all together" especially when a lot of things are interrelated,
and changing one thing then changes 5 others.  So, this will likely be an
intermittent mix of progress, error, and correction.

> And despite the top schema, the outer circle of one gear does not match the inner
circle of the other. Never.
> If it was, the smallest particle at the top of a tooth would block the system when
crunched in the pit.

Yes.  I have yet to add any clearance, and I need to learn more about how to
construct an undercut.
I found this fascinating page:
http://www.codeproject.com/Articles/1037482/Drawing-Gears-Circular-and-Non-Circular
But apparently the code may need some fixing to run.  I can read it and learn
from it though  :)


Thanks for keeping an eye on things and keeping me on course.
There is always so much to learn.

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