Re: roofs, was detail of AAR 1937 boxcar


Patrick Wider <pwider@...>
 

--- In STMFC@..., Randy Hees <hees@r...> wrote:

No argument on cheap or weight (but railroads were not historically
aggressive about reducing weight as one might expect.
Maybe, but the carbuilders obviously were, how else do you explain the experimental
lightweight box cars built by AC&F, P-S, General American, et al. circa 1940? To quote the
P-S ad in the 1940 CBC: "The necessity of reducing the weight of freight cars and
converting the saving into revenue load is well recognized."

And from the U.S.S. ad: "Reduction of dead weight with a corresponding increase in
capacity for carrying payload has been the outstanding feature of this new development in
freight car construction using U.S.S. High Tensile Steels." The ad goes on to press this
point further.

And it was the carbuilders buying most of the standardized roof panels. To quote the SRE
ad in the 1946 CBC: "Both the Improved Solid Steel Roof and the Murphy Welded Roof are
made of galvanized material, and the designs are such that the strength is uniform over
the entire surface of these roofs, and maximum strength is obtained in both designs with
the minimum amount of weight." Hmmmm, I wonder why they put that in there?


I wonder about repair, forming, construction and transportation issues.
Being railroad related industries, transportation wasn't really a
problem, and most shops had the ability to lift large items. In an
industry which was casting locomotive and tender frames in a single
pour, and dealt with boiler plate on a daily basis roofs would not have
challenged the technology.
I don't. Forming a 50' single piece of steel with stiffening ribs and complex impressions is
not easily done. And the more difficult it is to fabricate things, the more they cost. Cost is
an important factor in manufacturing. Are you saying that 50' single-piece roof sheets
have more advantages than disadvantages? Please name them. Making, moving, and
storing big, extremely flexible, easily damaged, thin steel sheets or panels susceptible to
corrosion (yes, I know they were galvanized) would be a pain for anybody, even the
almighty railroads. Underframes and car sides were shipped preassembled but they must
have presented fewer problems as you suggest.

I doubt that a typical shop tried to keep in stock replacement roof
panels. More likely they would have either welded or riveted a patch,
adapted the local common material, or ordered replacement material via
the car owner if substantial repairs were needed. (or just scrapped the
car and paid off the owner)
I don't. To quote the 1946 CBC SRE ad again: "Both of the above designs of roof readily
lend themselves to replacement of damaged sheets in railroad car shops." It says
replacement, not repair. Also, I can't imagine one railroad calling another railroad and
saying, "hey, I 've got one of your box cars with a hole in it's roof. Can you have SRE send
me two roof panels, pronto? We don't keep them in stock here at XYZ Railroad".

Does anyone have photographs of a railroad car shop circa our period of interest? I bet
there are some stacked SRE roof panels somewhere handy.

Pat Wider

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