The R-S really is a nifty railway!
Not much, but I do have a few photos of their freight equipment...
They were one of the first railways to use equipment made with aluminum:
Here's a builder's photo of an aluminum gon:
RS 609.jpg
Later, these were repainted black:
RS 662.jpg
R-S had some 1944 AAR cars made of aluminum, too:
RS 1010.jpg
Quite weathered by 1972! These look similar to the 1937 AAR cars modelled by Gold Coast - but the 1944 version of the design had Improved Dreadnaught ends (if you compare you'll see the difference) and were taller - the 1937 cars had 10' inside height, while the 1944 design had 10'6" inside height. This translated to an outside height about 6"-9" taller on the 1944 cars than the 1937 cars. Doesn't sound like much, but noticeable in a train.
They also had a unique design with all-aluminum body. If we're to compare this to the GC model the first things to notice are the straight side sills on RS 1500, and the ends: RS 1500 had a three-panel end with the top two panels having 3 ribs each, the bottom panel having 4. I don't believe I've ever seen a 3-3-4 Dreadnaught end like this anywhere else. 3-3-3 yes, but this design, no. Also note the arrangement of side panels: 6 panels - door - 6 panels. This was also rather uncommon (though not totally unheard of).
RS 1500 - 2.jpg
And a caboose. This is similar to the CN design represented by the Art+Detail kit. One could either use the A+D kit as-is as a stand-in, or do some kitbashing to get a more accurate model. The most noticeable differences are the wider-spaced side windows than on the kit, and the diamond-shaped windows on the end doors.
RS 14.jpg
Color Guide to Canadian Freight Equipment volume 1 has a section of colour photos of R-S equipment, freight cars and cabeese. There's one photo of I believe this same caboose in a later paint scheme, IIRC yellow with the later green R-S logo.
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