Re: New Accurail Offset twin hopper


Ed Hawkins
 

On Nov 17, 2009, at 10:14 PM, devansprr wrote:

Outside of the taper, and the number of ribs, it seems like the
various prototype cars had few spotting differences outside of safety
appliances? (and the obvious peak vs flat ends) Can someone educate
me?
Dave,
When looking at the various 50-ton AAR hopper cars that were built, one
of the key features I look at to distinguish one version from another
is the shape of the side sills. The earliest version (used from 1934 to
1949) had side sills that angled upward from the bolsters to the
corners and were straight between the bolsters. A later version (used
from 1940-1960) had side sills that were level with the track from the
bolsters to the corners and had a shallow fish-belly between the
bolsters. Note there's a 10-year overlap from 1940-1949 where new cars
could have either version. By the way, the same side sill variations
were present on 70-ton AAR offset-side hoppers.

The Atlas model has side sills representing the early version while the
Athearn and Kadee models have side sills representing the later
version. The image of the model on the Accurail web site shows a side
sill of the early version.

Then, of course, there are the differences in how the side sheets
nearest the ends were formed as well as a variety of different end
arrangements. The combinations of all of these variations are
practically endless, not to mention other more subtle differences and
specialty items.

Some ends with flat tops used angles extending from the top of the end
to the end sills, others used channels extending from the bottom of the
end sheets to the end sills, and some used closely spaced Z-sections.
Further variations include ends having extensions (i.e., peaked
ends/heap shields) of various shapes. All of these combinations add to
the complexity and cost of tooling.

It's my understanding that Accurail is using the same end configuration
for their 50-ton model as they used on their 70-ton model. It
represents (poorly in my opinion) an end arrangement having Z-section
vertical supports that are closely spaced near the middle. The
Z-sections on the model aren't Z-sections, and instead are rectangular
cross sections, because otherwise the body could not be ejected from
the mold. Unfortunately, combining this end with the side arrangement
creates a very rare prototype 50-ton AAR hopper car.

There are other end arrangements that would be a better choice for more
road names. It comes down to the tooling cost involved with making
other variants. Since Accurail already had the end tooled from their
70-ton model, they chose economy by reusing the end despite the
relative rarity of the car that will be offered. Depending on sales
once the models are released, perhaps Accurail might be open to
offering other end variations that were more commonly found on
prototype 50-ton AAR Standard hopper cars.

My intent is NOT to hurt Accurail sales, but rather to help educate
consumers in making an informed decision on what they buy. To that end
I will be happy to assist any manufacturer interested in producing
accurate models of AAR hopper cars.
Regards,
Ed Hawkins

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