I was working on modeling rail units for my BattleTech battlemap, and while poking around the Internet looking for specs and dimensions for rail cars, I remembered that I had a box full of detailed large-scale models of various rail stock kicking around. So I dug out my old HO-scale electric trains, and have been using those as a basis for the POV models. Though I'm using the renders for their original intended purpose, they're not really BattleTech, so I've broken them out into their own section.
Alco Century 430, in Rutland Railroad livery. This locomotive never actually existed; Rutland Railroad folded before the Century line was released. But to be fair, the Tyco locomotive I largely based it on is in Rock Island livery, which the Century 430 also never actually wore. I also used Green Bay and Western #315 as a guide for a lot of the detail and proportion adjustments where the Tyco is inaccurate, because it's one of the very few — possibly the only — surviving 430s, and there are a lot of photos of it available online. There were only 16 of them built, and three of those were Alco demo models.
Standard plug door boxcar, based on one of my Tyco Burlington Northern cars.
Single-dome tanker car. The Tyco car I used as base is done up in Coca-Cola
colors, but I based a lot of the detail on a photo I found
on Flickr of a Gulf Oil tanker that appears to be the same model car
that the Tyco is based on.
While I was looking for the box with the trains in it, I found a '50s-era
construction toy called American Skylines
that I inherited from somewhere and had forgotten about. It's a sort of
pre-Lego thing for building Art Deco skyscrapers. It claims to be HO-scale
— though it also claims ⅛" = 1', which works out to 1:96, and
it looks to me more like 1:72; HO is 1:87 — so it can be used to build
scenery for HO-scale trains.