ok, a really small version, but I don’t have more space The two spans are 5.5" and 9.5" (about 75ft and 125ft scale). Any idea what kind of bridge I can/should build for that? Clearance is 0.5" (6.5ft) and the track is slightly curved (no idea about the radius) – so the prototype truss and plate girder bridge might be difficult, no?
The radii look large enough that adaptations of double track through plate girder bridges or through truss bridges might work. Wood (or concrete depending upon the era modeled) trestles would also work. Since the clearance is small, you will need to be very careful of the depth of the bridge below the track. No matter what you choose expect to have to do some kit-bashing or even scratch building to make them work out.
BTW, looking at Walther’s selection of N-scale bridges for some ideas might help narrow this down.
Thanks for the tips! I also saw some nice wood trestle pictures on here, so maybe that’s the easiest to model and adapt. the prototype hodgepodge of through plate girder + truss + masonry seems too tight to model (span-wise and clearance-wise)
I agree that a trestle would fit the bill. But I think that you could build a concrete one. Use precast type pieces for the track bed and support them with round pillars. Each “bent” could be three or four pilings. They can also be spaced out more than the bents on a wood trestle.
Something like this -
What mine is made out of is some Atlas True Track ballast sections turned upside-down and square styrene strips glued on the top edges. You could also make the deck sections from styrene with some square strips glued to the sides, then ballast the track once it is in. My pilings are square but yours can be round. I would use dowels and smaller (thinner) cross supports.
Regardless of what style/ type bridges you decide, another problem area would be how to address the river banks. There is very little space between yard tracks for such a river that would also incorporate an island. Some sort of stone/ concrete retaining wall will be needed up to the abutments of that longer span (one w/ cars on it).
The longer span appears to have a very small radius and a truss bridge, like your prototype may work, the shorter tighter radius may work w/ using a plate girder, Note a Central valley double track could be narrowed if added side clearance is nec.
Steel or wood trestle would be the simpler way, however, the look of a truss or girder may be far more appealing for your final scenery.
My initial thought was a brick arch for the short bridge and some sort of curved girder bridge for the long bridge.
Curved girder bridges are not really curved but a series of straight sections that should be easy enough to bash out of a couple of commercially available kits.
Looks like it will have to be all steel or a low timber. trestle and a steel bridge.
Don’t forget the river banks will have to be shored up so the bridge abutments don’t get washed out. they will be right on the rivers edge by the look of it…
Really good thoughts - I kept the river shallow out of pure laziness (not cutting another layer out and setting it deeper into the cross beams). This is something that is still possible to do, but then the river banks would also be much steeper and even more unrealistic (it’s already a stretch, I know, about 6 scale feet to the water surface is not really enough for the typical flooding, etc.)
I’ll try my luck with a concrete bridge that will also span the “island” very much like the prototype, and then a “curved” plate girder with modified Model Power bridges to fool around. if that works (and the upper level is added) I might try “curved” box girder bridges.
…don’t know if this is what you’re looking for, but I’ve always liked these two truss bridges on the cover of N Scale Model Railroading, and am looking to incorporate this “two-bridge look” for over a creek on the CR&T.
The two spans are 5.5" and 9.5" (about 75ft and 125ft scale). Any idea what kind of bridge I can/should build for that? Clearance is 0.5" (6.5ft) and the track is slightly curved (no idea about the radius) – so the prototype truss and plate girder bridge might be difficult, no?
