I’m building the Walthers Double Track Swing Bridge. I am going to modify it to fit a prototype railroad I am modeling. It will have 1 Track to one side and a two lane highway on the other. I don’t have any locos or cars to see how much space I have for them. If your interested in looking at trhe bridge, go to a search engine and type Canso Causeway in Nova Scotia, Canada. Again if someone can tell me how wide normal locos and cars are I would appreciate it. Sorry about some confusion, I’m modeling in HO Scale and will be using Diesels, no Steam. I’ve read the 1.5 inches answer and that’s what i’m looking for. Maybe some cars are wider???
My LL F2 A/B set is just under 1.5 inches wide. Count on a bit more for a steamer’s cylinders, so an even 1.5".
Realistically your question doesn’t quite have an answer - I assume you are talking about HO scale (I don’t think Walther’s makes the bridge in other scales).
Railroad cars are sized to fit “plates” like “Plate C” or “Plate F” - you’ll often see “Exceeds Plate x” on the ends of high/wide cars.
http://www.trains.com/content/dynamic/articles/000/000/003/045jcxoa.asp explains this.
http://www.trainweb.org/utahrails/drgw/plate.html has the actual dimensions.
Model equipment varies by how much lattitude the builder took with scale nd on steam engines how much fidelity the company/modeler took with the cylinders.
Best bet. Buy an NMRA clearance gauge. A very useful tool.
Dave H.