Southern Pacific AC-9 is a free Model Railroad Discussion Forum and photo gallery. We cover all scales and sizes of model railroads. Whether you're a master model railroader or just getting started, you'll find something of interest here.


Midwest Alliance Rail Sys
I'm primarily an HO railroad modeler (mainly because that's what I have - the momentum factor), but I confess I'm mesmerized by the "bigger stuff". I own a locomotive and a caboose in "S" scale, and a locomotive and a boxcar in 1:29 ("G") scale.

To come to the point: I own a brass HO scale Southern Pacific AC-9, and I really enjoy having it, but if I could find an "O" version, like the Biblical "pearl of great value", I'd probably sell the HO model and whatever else I'd need to in order to own the "O" locomotive, and I'd might even switch to "O" altogether.

I know Lionel made one a few years ago. I assume it's three rail. Does anyone in this community know how "faithful" a representation it was vis-a-vis the prototype? (I know that a lot of Lionel's trains have been "adjusted" in terms of dimensions, etc., in order to run on the smaller radius track some folks use.)

Does anyone know of a dealer who might have or be able to get an AC-9?

This next question will show you what a newbie I am at "O" related matters: How hard would it be to convert a 3-rail locomotive to 2-rail?

Thanks for indulging me!


Entrepreneurial Teen
I'm not an 'O' guy, but it sounds like you're on the right track. If you're trying to keep it true to scale, a general rule is to stay away from Lionel and some MTH. They make O 'gauge' as opposed to O 'scale,' basically meaning they adjust dimensions to fit their needs, so it's not consistent. Atlas and Weaver are true-to-scale 1:48 models.

I don't know how close any of these come to the AC-9, but there certainly are O scale steamers out there: Scale - 2 Rail


Wannabe Engineer
I've seen them on e-bay but I can't afford the $1000 and higher price tag, yet. I would love to have one as well.

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