Pretty-well all of my mainline curves are superelevated, including those on bridges. One long one, on a 2.5% grade, turns the track 180° and enters immediately into an ess-bend (partially on a bridge) and another ess almost immediately after that.I have a short video somewhere, taken with the camera on a flatcar right behind a steam locomotive's tender, and the superelevation is apparent, even though it's not too extreme.
I've also done superelevation on a portion of the layout's upper level, which is cork on sheet plywood. For that, I used strip styrene under the tie ends on the outside of the curve. I found the riser method to be easier, as the vertical spiral transitions are self-forming.
Wayne
Hi,
I use superelevated curves on my visible portions of main line track. I like the appearance very much but it can be a bit of a challenge to get everything working properly.
You can see that this Mohawk is leaning into the curve. (the siding on the right is flat) This happens to be at one of the places where I eliminated the superelevation on that distant, short curve because the "overlap" caused too many derailments. Idealy there would be at least two feet minimum of tangent (HO) between these curves for the transition to take place.
As Carl points out, the ballast profile is what the railroad uses. On bridges, the ties are chamfered to fit the bridge girders. On some main-line, high speed curves, the outside rail can be as much as 8" above the inside rail!
In HO, I used .030" styrene strip under the outside rail. I lightly tacked the track nails then gently coaxed the strip under the rail before gently tapping the spikes in place, never completely "setting" them but leaving just a few thousandths play. I used small dabs of Goo and a few thumb tacks to hold everything in place.
Where the curve enters the tangent I made transitions using .010" then .005" strips for maybe 8" of each step. I also use spiral easements which also helps with the transition.
I have to be sure every car has enough lateral pivot to negotiate the rise to the superelevation. A few rigid wheelbase engines 2-10-2s) still give me problems but I have pretty much worked out the "kinks" there.
I seem to recall a manufacturer of HO flex track that made superelevated track. I'll have to update this post when I find it...
You are working in N scale if I recall correctly, TrainsRme? I believe Kato makes a superelevated curve.
http://www.katousa.com/HO/Unitrack/g-concrete.html
And in N:
http://www.katousa.com/N/Unitrack/concrete.html
Since you already have tape on hand, here's a method using tape.
http://www.rgwrail.com/SuperElev.pdf
Have Fun, Ed
I built two Free-mo modules with curves that are eased and superelevated.
I used Walthers Code 83 flex. For the non-eased middle part of the curve (48" radius), I used .040" thick styrene shims. I placed them at the outer edges of the ties.
To go from the straight flat section to the fully superelevated part, I used graduated thicknesses of shim. This fit in nicely with the curve easement, and everything looks and works great. There have been zero derailments caused by this setup.
The .040" shims provide about a 2" superelevation in the main part of the curves. Done with this size shim, the superelevation sorta shows and sorta doesn't. By that I mean that it doesn't quite draw your eye, but you still "see" it. It just looks right, and I'd do it again the same way.
Ed
The way I've always understood it, railroads build superelevated curves with the ballast pile, not the roadbed. If you use the styrene shim, your curves will look like the prototype.
If you use the riser/subroadbed trick like described above, it will look like this tilted.
Odds are that once your ballast is glued in place, it won't matter what you use for the shim. But, to be on the safe side, I'd stick with the styrene. Anything at all porous might swell when wetted with the glue for the ballast then shrink back unevenly when it dries. The strips you need would only cost a few bucks.
I have the right to remain silent. By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.
I did what Wayne is talking about on my previous layout using risers and cutting the subroadbed from 3/4 plywood. I will be doing the same again on the new layout, two sheets of plywood were just picked up on Friday.
Lynn
Present Layout progress
http://cs.trains.com/mrr/f/11/p/290127/3372174.aspx#3372174
Depending on the construction methods used for your layout, here's another option for superelevation:
If you use open grid or L-girder benchwork, superelevation is easy to add, including the vertical easements into and out of the curve.
I use 3/4" plywood as a sub-roadbed, but any similar-type material, or even spline roadbed should also work. Install the straight roadbed on either side of the curve by fastening the risers to the joists, except for the last riser beyond the ends of the curve. Install risers to the underside of the curved roadbed, but don't fasten them to the benchwork just yet. If your curve is on a grade, as most of mine are, raise the roadbed through the curve to the proper height, then mark a pencil line on each riser which corresponds to the top of the benchwork to which it will eventually be fastened. If the track through the curve is to be level, adjust the risers accordingly, then make the lines. Next, choose the riser closest to the mid-point of the curve, raise it to the proper height, then push the bottom end of the riser towards the outside of the curve. Re-align the height line on the riser so that its inner end corresponds to the top of its benchwork member (the height line will be tilted, with the end on the outside of the curve somewhat above the benchwork). I've found that the best way to establish the amount of superelevation is by placing a train on the curve, then adjusting the off-set of the bottom of the riser until it "looks right". I use a C-clamp while I'm making the visual adjustments, then, when I'm satisfied with the appearance, that mid-point riser is screwed to the benchwork. Because the roadbed is torsionally flexible, each riser on either side of the mid-point will now be off-set from the vertical, to diminishing degrees, as the distance from the mid-point increases. Working from the mid-point of the curve, carefully raise each riser so that the inside end of the height mark aligns with the top of the benchwork to which it will be fastened, making sure to not change the angle of off-set, then screw the risers to the benchwork. This allows the roadbed to form its own easements into and out of the super elevation. I did all of mine with the trackwork in place.
Hi Guys n Gals,
Hope all of you and a great weekend, I took my Grandson to The Columbia Gorge Lines modelrailroad club here in Portland and he had a blast!! anyway I have a question, I saw this video on YouTube on constructing a super elevated curve, by using styrene strips, I think, 010' thick, could I use the woodland scenics paving tape for the same usage, I have two roles of it that I haven't used for anything, thanks MRR'ders!!!
Trainsrme1