Track center spacing for double tunnel portal

Hi all,

I am putting together the subroadbed for my layout, and it occured to me that I don't know how close the tracks should be to fit through a double track tunnel portal. The subroadbed is 2" wide which is the width of cork roadbed.

I was thinking on 3" center to center, but that may be too far apart to fit through the portal.

Thanks

Shaummy

 

I use 2". On curves between 24" and 30" radius, add 1/8", under 24" radius add 1/4".

Gary

 

if 18" then add a half inch at least.

 

You could always mock up a double track curve with flex that is the planned radius and test you longest equipment to see just how much room you need.