Finally, my little Atlas RS1 Switcher goes through the entire spaghetti bowl with never a glitch! Even the slightest, unusual tiny little noise at a joint, makes me go in with a needle nose file and further file down the solder that may have gotten to the inside of the rail.
But, as soon as I attach a freight car....before too long the diesel is dragging it on its side. I guess, despite the little steel weights, it is still too light.
Gotta keep at it until ever car can negotiate every turn, every joint. Model Railroading is like Golf! Frustrating! Ah but the rewards are great!