On the layout, when I first put track down, I poured concrete to set it on. I thought this was the best way to keep the track from settling and to prevent the ballast mixing in with the soil under the ties. I built and leveled forms and poured concrete to form the roadbed. Trains have been running on it fine since then. However…
It turns out that since I poured the concrete in sections that were individually leveled against the preceding section and themselves, the track isn’t really level. This wasn’t as obvious running DCC locomotives, where back-EMF tells the decoder the motor’s speed so it can adjust to maintain speed on grades. But now that I’ve added live steamers, it’s much more obvious.
The live steam locomotives slow down a significant amount in two places on the track, both curves where–remeasuring–it turns out there’s a significant grade transition that isn’t visible to the eye but is quite pronounced when measured with a 6′ level.
This means that I’ll have to shim the track level and reballast to improve the running of my live steamers.