My two cents on the excellent weathering notes that have already been offered by the group: as with most modeling, I think we come closest to verisimilitude—to fooling our viewers into thinking they are looking at a prototype—when we model the common, the ordinary, as opposed to portraying the unusual and the extraordinary. This applies to weathering as much as it does to most modeling, and I often remind myself of this lest I go seriously "off the rails."
That's my rule, but as your model railroad is yours—and yours alone—you should do anything you please.
La Cañada, CA
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