Here's something you could toss in to a route.
www.railpictures.net/viewphoto.php?id=339228
www.railpictures.net/viewphoto.php?id=339228
Remarks: Now that’s a curve! CLD Pacific Grain’s trackmobile pulls four newly-unloaded covered hoppers around the loop track at CLD’s O-Dock on the Willamette River in downtown Portland. The bulk carrier Thalassini Kyra, visible at left, is in the process of taking on a load of export wheat. Additional cars wait in the small yard at right for unloading. The loop track is approximately a 45 degree curve -- an 18-inch radius in HO scale.