Jay Bingham asked:

I am interested in determining what private owner tank cars were
regular travelers on Northern Pacific's mainline across the Rocky
Mountain Division circa 1930-1940. Specifically, I am interest in
the car owner and stenciling, the product and the type of car. I
would like to model a few tank cars for my HO rendition of the Butte
Shortline.

Well, as my previous post said, the bulk of traffic in those days was
petroleum products (gasolines, diesel, lube oils, asphalt, and heating oil
I would imagine in that neck of the woods), and acids. In fact, the
biggest SOURCE of sulphuric acid is copper smelting, so my guess is the
Butte area generated quite a few carloads of the stuff. Those are
specialty cars for which there are no exact models that I'm aware of
(Sunshine where are you?!?).

As for the petrol stuff, which brands/companies were biggest in that area
in that era? American? Chevron? Texaco? Conoco? Sinclair? A little
research on your end is needed. Which had dealers on the NP? Then you
need tanks for those brands to haul products in to the oil dealers for EACH
of the popular brands. The various brands didn't play well together so
they had to have their own dedicated dealers. Most towns of any size (like
county seats) had at least one, and two or three dealers were not uncommon.
Sometimes they even shared the same siding. I imagine Butte had a bunch
of dealers and got quite a few tanks.

Now if any of the brands are "baby" Standards (American, Chevron, Esso,
Socony/Mobil, and Sohio), you need lots of UTLX tanks, the bulk of which
were Union's own X-3 design. This looked a lot like an ACF Type 27 but had
full wood platforms at each end, and in that era the side running boards
were wood too. (Another needed kit: frame/boards to kitbash the
Intermountain Type 27 into an X-3.) Run-of-the-mill UTLX tanks rarely if
ever had logos in that era. Plain black tanks are your friends. Give lots
of them a good home.

Scott Chatfield