@DoubleDAZ posted:Well, like I said, I use 3”, but if you want it closer to the walls, you need to test the overhang on your engines.
As for O72 curves, it all depends on whether or not any of your equipment requires O72 curves, or just runs better on them. A lot of folks don’t like the look of the extra overhang you get with tighter curves, but I can honestly say that’s not something I’ve ever noticed. You do notice it if you look for it though, but all I care about is that the equipment goes around the layout without derailing. I’ll redo my latest version with O54 curves so you can see the difference.
I think you’d be crazy not to have 2 mainlines on a layout this size, but it does increase the cost substantially. They also reduce the space that’s available for scenery and spurs, but they let you run trains in both directions without having to use passing sidings and control your trains manually as well as providing over/under options. If you’re into switching and servicing businesses on spurs, then a single main might be more to your liking.
With your recommendation I would like to keep the two main lines. I think having 054 curves in tunnels would hide the over hang issue. I’ll check out the differences with 054 curves. I do not have the experience with any curves larger than 031 LOL
