... connected by a 90 degree double track curve at one end of the room. Hi Ian, I think you mean 180 degrees? Martin. posted: 14 Jul 2008 02:40 from: Ian Everett Martin Wynne wrote: I think you mean 180 degrees? I'm a daft buggar- of course. Hangs his head in shame... posted: 14 Jul 2008 03:41 from: Martin Wynne Ian Everett wrote: 2) Using an existing room 8' wide. Hi Ian, Something like this maybe? ian_room1.png The curves are approaching the limit for P4 but should be just about do-able with some gauge widening. Everything depends on what you want to run round them, of course. You could ease the radii a little by shortening the S-transition zone, but that might restrict the available length for the station throat. How long is this 8ft-wide room? regards, Martin. posted: 14 Jul 2008 03:55 from: John Lewis What you don't say is what sort of trains are you planning ...