That sounds doof easy the way you describe it, Douglas. But if there are slots (or spikes) for a straight piece, then putting a curved track in there would require a lot of bashing, sounds like. At least it would not be a matter of simply laying in flex track. Or?
is there enough room under the bridge to install it upside down like above
I think the bridge might have built in ties and spikes and rail slides in. Unslide the rails. You can nip or file off the spikes. Or you can build up the surrounding area with styrene. Maybe cover the whole bottom deck with sheet styrene. Maybe ballast over the whole deck. Experiment.
Not sure what you mean, Greg. I dont’ think the bridge in that image is upside down. It’s just a deck girder, although I think it was Ed who pointed out it looks awfully tall.
But to answere your question, I have enough room for a deck bridge, but as I think I wrote in an earlier post, someone baiting a hook in a dighy upstream better look up once in a while because the water will have to be within a few feet of the bridge. Ed commented that prototype railroads would not use a deck girder if the water was that close. I could also make a narrow gorge here, but then I have the problem that my bencwork will get in the way downstream.
Hmmm… I could reverse the course of the river and then add a falls just before the bridge…
Spoken like an astronaut. Have you no fear?
It’s good counsel, actually. I think I might look at some of the new old stock my LHS guy has next time I’m down there. Getting a look at some of these models up close would help me imagine the work involved.
Again, thanks all. It may seem to you like you repeat yourselves endlessly here, but each time you do, at least one modeller learns something.
-Matt
I’d skip the fiddling around and simply remove the existing floor, then add a new one, using fairly thick sheet styrene. Nobody’s going to look at the underside of a low bridge, and the track can be ballasted…no need for more details.
One thing that’s not being taken into consideration is that the needs of model train bridges do not require the same engineering details of the real ones…if you want to spend a lot of time on those details, then do so.
Otherwise, make your bridge accommodate the curve(s) that you need to get your trains to go where you want them, and don’t sweat the details.
That long bridge over the river, which I showed earlier, has a Central Valley Pratt truss bridge that’s bracketed by two Atlas formerly through-girder bridges, which have had their decks removed, and the girders flipped over, and placed closer together, with cross bracing added - not because I wanted those details, but because I wanted the entire bridge to be strong enough to not only handle heavy trains, but also be strong enough to be removed as an entity, not as a bunch of broken-apart bridges. Nobody sees those details.
It does what I need it to do.
Here’s a curve (and a grade) on a succession of fairly short bridges…
…somewhat similar in execution to the modelled bridge that I showed earlier that’s made-up of short spans to accommodate the needed curve.
Wayne
Move the river back to where it was and build a twin track bridge…or move the turnout even further back and build two single bridges that carry the two routes…
The Atlas plate girder bridge isn’t made to use a straight track; the floor has cast in place ties and has grooves that the rail (code 83 or code 100) are slid into. The result is that the track sits unrealistically low - the track is in the very bottom of the bridge. On a real bridge, the track would sit higher up. I’ve used the Atlas bridge on my layout using Kato Unitrack (track and ballast strip combied) - I just removed the Atlas rails and put the Kato track over it, fill in with ballast. The result puts the track at about the correct height for a real bridge. If you use flextrack, maybe remove the Atlas rails and glue a flat section of plastic sheet in place over the ties, then lay your track over it…or just cut the sides off of the bridge and attach it to a new plastic sheet floor - which you could make as wide as you want/need.