Here’s a video I made of one of my mules (a 2006 vintage Kato F7) traversing an N gauge turnout built with Proto:120 flangeways some .016″ wide. The locomotive has Proto:160 wheels near enough to scale to call them that and thus designed to interact with Proto:160 track and its .0115″ flangeways. Anyways they play well enough together in this instance.
And another video showing how the loco traverses the diverging track.
And a photo showing the pizza cutters I made up:
AH
Cascade Division 