Phil Buchwald wrote:

Also, along with the discussion about single sheet vs multi-
panel roofs: The Milwaukee cars' roofs were welded at the seam caps,
which effectively made them one piece roofs. But the West Milwaukee
Shops were huge, very modern facilities (for the 1930s, at least!)
which could handle picking up a 40' x 9' piece of sheet metal. Were
other railroads' repair and construction forces geared to handle
this big chunk of steel?

When welded, the roof has considerable stiffening in it due to all the seams and panels, quite different from the "single sheet of steel" mentioned earlier. An assembled steel roof is not that heavy, compared to other things which are manipulated in car building like underframes, and any shop that could build cars could certainly lift and install roofs.

My money is on several of the theories already presented in
this string: Transportability, and repairability. Repairability
includes both the ability to have one damaged panel replaced, as
well as being able to handle the panels with reasonable size crews.
(I'm lumping railroad built or upgraded cars into the "repair"
category, since they would use the same facilities and crews.)

I think this is sound reasoning.

Tony Thompson Editor, Signature Press, Berkeley, CA
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