Transmission gurus: Does this gear look right?

[amalventano1 at tds.net (Allyn)]

> Anyway, there's a notch in every tooth, all the way around. 
> But someone has told me that this is actually the way VW 
> machined it to be. Is that true? Is this the way it should 
> look? Why would they do that?

Yup, that's expected.  I was able to ask a rather old gentleman about this -
as he was working a burr out of one of the gears on the submarine (a few
subs ago).  To get the proper picture, you have to realize that the man was
basically the only guy allowed to bring metal into a tented-off area, and
was flown in to do his work, on a set of gears so expensive that the Navy
*leases* them instead of owning them (example - the bull gear is a few
levels in diameter).

Anyhow... He described these grooves as methods of fine tuning the transfer
of load from tooth to tooth as the gears rotated, effectively shifting the
torque to a different axial band of the teeth as the load is transferred
among the teeth.  The basis was that compromises had to be made when
selecting the angle of the cuts, and the groove was a way of cheating the
system and redistributing the load among each individual tooth.

I may have skewed the exact answer slightly, as I only remembered/understood
the theory and not his exact wording, and this conversation took place
nearly ten years ago, but I hope it helps nonetheless.  I put quite a bit of
faith in this guys' words, as he was probably the only man in the USA
qualified to take a bunch of files to a multi-million (billion?) dollar set
of extremely large gears.

HTH
Al

Allyn Malventano, ETC(SS), USN
87 Rieger Scirocco GTO 2.0 16v (my daily, 220k, rocco #6)
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