While the girders and rails won't be horizontal, keep the bents vertical to the horizon (straight up).
Mark
I prefer to build my scenery and insert the track elements, measure from the track down to the terrain at the places where the sills will rest, and then build the trestle bents to suit. I add 10% so that I can nip off what must be removed in order for the trestle to nest under the tracks and keep them at grade.
In other words, I fashion the roadbed first so that the grade is well established. I lay track over the area, suspended by something over the gap to keep it from sagging. I do the measurements up to the bottoms of the ties vertically from where I want each sill. I turn to the bench and begin to make each bent frame customized to fit...plus 10%. When I go to install the trestle, I always have to use a nipper to remove a 1/8" bit here, more on the other side of the bent, and so on, until I can just slide the whole thing into postion, gently prying up the tracks if I must, and it should sit there almost without needing anything else. Of course, I do glue it, and the tracks to the roadbed atop the trestle. Why tempt fate solely on the basis of hubris?
-Crandell
If you have a 2% grade and the bents are 100mm apart, each bent is 2 mm taller.
Wolfgang
Pueblo & Salt Lake RR
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