What woyld be a standard height for one train to pass under another. I have tried different areas and unable to come up with anything. don`t tell me as high as your biggest car please. there must be a standard thanks.[?][:I]
An NMRA guage would be helpful for you, but i think 3" would be good.
Well, if you ask me, it depends in what scale you are modeling. For example, if a bridge in 1:1 scale is 20 feet high like they are in my area, then you would convert that to fit your scale (or at least as close as possible. Im not aware of a “standard”, but then I am not a pro. I try to model everything to scale as I can so that is the standard I go by I guess. most of my bridges are 3 1/2 to 4" high with a couple at 4 1/2". In HO of course you are talking 87 feet=1 foot or 6 feet = roughly 3/4".
So for easy figuring a bridge I do at 24 feet high in 1:1 is 4 1/2" high in 1:87. (in 1:87 scale taking 6 feet times .75 inches = 4/12" for my 1:1 scale 24 feet bridge).
The standard has shifted as cars got taller. Some cars are now taller than engines.Pick your era and you have different requirements. And on the side-to-side it depends on what you are running. Full length passenger cars (85’) on an 18 radii will require more clearance than a 36’. As you model, your compromises and compression will be part of the clearance requirements for your road.
Standard min. vertical clearance today (over rails) is usually 23-24’.
Hope this helps.
Thanks guys helps alot
For modern equipment, figure 25 scale feet from the railhead. See: http://www.nmra.org/standards/gauge.html “Standard S-7 Clearances and the NMRA Gauge” for a good explanation.
I don’t think the NMRA gauge accounts for the taller rolling stock on today’s railroads, such as stack trains or Auto-Max cars. In HO scale, I allowed 4 inches, and had to raise Woodland Scenics tunnel portals or grind out the tops of them to clear stack trains.