I'm laying some track that will later be inside of a tunnel.
I imagine that prototypes superelevate their curved tunnel track - but which tends to perform better?
On my layout this is one of the tightest curves at a little over 22" radius.
Since the tunnel track can't be seen I'm wondering about the added effort of superelevating that track.
Any thoughts?
i would think speed through long tunnels is usually somewhat restricted. if you won't be able to see it, why bother. you might just be asking for trouble. i would strive for the simplest and most dependable track work in locations like that.
grizlump
Unless you run your trains at scale speeds measured in Mach numbers, superelevation is purely cosmetic. OTOH, proper spiral easements are easily worth the effort.
Every millimeter of track I have laid so far is part of the netherworld, never to see daylight once the landforms above it are completed (unless I lift a removable piece of scenery for access.) That said, I have a couple of curves (610mm = 24 inch radius) which I superelevated in different ways to see which techniques would work. (At last report, tilting the subgrade had a three-length lead on shims under the roadbed, with shims under the ties a distant third.) Other curves are flat from one side to the other. There is no perceptible difference in performance among the several variants [which include transitioning from level to grade and vice versa on several curves and through two turnouts(!!!)]
Unless you want to experiment with superelevation and hide the results where the sun won't ever shine, lay your tunnel rails flat. The only exception would be if the visible rails approaching the portal are curved and superelevated - in which case, carry the superelevation into the tunnel or all the way through if the curve is continuous from one portal to the other.
Chuck (Modeling Central Japan in September, 1964)