On 3/23/2010 3:31 PM Greg.Procter spake thus:
>> On 3/18/2010 10:26 PM Twibil spake thus:
>>
[quoted text clipped - 8 lines]
> I suppose one could place a model on a flat surface
> and measure deck height from the flanges.
One could. One could also, conceivably, measure deck height from the top
of the trucks, or the level of the trainline, or whatever. The point I
was trying to make is that the railhead is the only sensible reference
point for any car measurements, since it's the only place that can be
reliably and precisely measured from, regardless of the weight of rail
used or other variable factors.
Someone may want to know how high the sill of a boxcar is from the level
of the ties, for example, for the purpose of loading the car, but that
isn't ever going to be a precise measurement, since it depends on the
height of the rail (and maybe even the thickness of fish plates, etc.).
For your purposes, measuring height from the flanges amounts to the same
thing, as this is also a precise reference point (well, as long as you
have the same size trucks and wheels as those the car was designed and
drawn for). All you need to do is subtract the flange height if you're
using a measurement made from the railhead.

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You were wrong, and I'm man enough to admit it.
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