"David Lesher" wrote in message
...
Side topic:

I have read that the Wehrmacht's tanks, esp. the later ones that
were so large, suffered badly from final drive failures. So much
so that a road march of them for any distance would disable
say 33%. This helped me better understand Allied anti-railroad
tactics...forcing them onto the roads.

[They also lacked tank retrievers of enough strength to
salvage them....]

The failures were because of 2 basic reasons: they lacked
sufficient chromium to fully harden the gearing, and the second
was my question.....

This source (that I now can't find again...) said there was a
way to better design/machine the ring gears needed, but Germany
lacked the tooling/resources to use that approach, and instead
used less strong methods. I inferred the better way needed more
time or a better mill but beyond that, I don't know.

I'm curious about what that might have meant, and wonder if anyone
can speak to gear design issues...

I haven't been able to find adequate details of the problem from a
military historian / machinist. Supposedly the bombing had purposely
targeted the makers of gear hobbers and shapers, along with ball
bearings. The stainless tanks and plumbing for the hydrogen peroxide
subs consumed most of their chromium and nickel.

This may help but I can't check it with dial-up:
http://www.youtube.com/watch?v=k9NCPthmTsU

The Wiki is as good as anything else I've found:
http://en.wikipedia.org/wiki/Panther_tank

jsw