I’m just getting into n scale modelling. My space is pretty tight, so I want to know before I plan out the layout how tight I can make the turns. Both for hidden track and visible. Meaning, what’s the smallest curve radius that will still look good, and what’s the smallest radius for track that no one will see?
While it depends on the equipment operated, the vast majority should be able to operate on a “standard” Atlas 9-3/4in radius curve.
I suggest 11in or 12in for hidden track. 18in for visible main lines. Industrial tracks where only 40’-50’ cars and small locos are operated could be as tight as 9in-10in for contrast and to fit into tight places. A branch might be 15in for scenic contrast with the main.
I like to use code 80 rail for main lines and code 55 for sidings and spurs for scenic contrast. This is easy to do with Peco track. Other brands take some work to properly align and attach the different sized rail.
This page on the NMRA’s site http://www.nmra.org/standards/rp-11.html gives a set of recommendations based on the equipment you are using or planning to use.
Enjoy
Paul
I have 9 3/4" radius curves on my layout, dictated by the size available to me. In my experience, diesel engines the length of a GP7 work fine, and look okay. Engines the length of a GP38 work okay but look somewhat iffy, and anything longer will work and look awkward.
If I had space, I too would try to keep a minimum of 18" radii on mainlines, 15" on branches, and 12" in spurs. And those are minimums.
—jps