Single Track Stone Tunnel Portal for O Scale Model Trains

This is more detailed version of my original tunnel portal for O Scale Model trains like Lionel or MTH. The exterior dimensions are based off the MTH single track portal. The internal dimensions have been expanded to give more room for trains when the portals are installed near curves.

This is a modular design that can be printed on smaller 3d printers like the Davinci Mini.

The internal dimensions of the portal when assembled are:

single track width ~4.8 inches
146mm height ~5.75 in