I agree, but it didn't come across well in the photos. I use roof brown, rail brown, or sometimes Rustall but the latter is raw iron oxide and needs to be toned down at least on a truck that is supposed to be "in service".
The B&O F units look to have been weathered with only grimy black or something similar. It's easy to overdo it. I haven't tried to weather any Genesis F units yet... only ones I really have "in service" are the warbonnets. They did get some dirt on them, but in the heyday of the 1950s they sprayed the trucks silver on every run... which must have been quite a mess for the maintenance shops once they got about 35 coats of paint.
Andy
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