Ned Carey said:

Don and Tony (and anyone else still listening)

Well, I may be the only one still listening, and...

I don't get it. What advantage is there to lighter cars? Yes you possibly
could get away with lighter cars today but how do you benefit?

Lighter cars, less load for the loco. Of course, rolling resistance of
the trucks often overwhelms car weight, but if everything else is equal,
weight really does matter.

The only disadvantage that I could possibly see is your locos don't pull as
much. Who cares? Just double or triple head them like the prototype. Most
modelers have more engines than they can justify anyway. Here's a reason to
run them. Mike Brock has sometimes chimed in on this issue to say that steam
engines pull about a prototypical amount up grades with current NMRA
weighting.
The WM used 7-10 engines up black fork grade. Why shouldn't I?

Mmmmm. Black Fork, extremely typical prototype situation. Yes, if you
actually model Black Fork, use a whole buncha consolidations. Practically
any other mainline in America, nope.
I fully agree we can double-head, though with steam models they don't
always run well together. Diesels, sure, add more units just like the
prototype and most run better together. DCC is fixing some of the
inter-loco compatibility running problems, but not all. And BTW, Mike means
well geared, well motored, well weighted steam. Not all of us have every
model in that condition (though Mike may well have).
All that said, I still use NMRA weight recommendations, and try to pay
close attention to rolling qualities of trucks. For me, that's the right
compromise. As with so many things, YMMV.

Tony Thompson Editor, Signature Press, Berkeley, CA
2942 Linden Ave., Berkeley, CA 94705 http://www.signaturepress.com
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