Tunnel & Portal Tutorial

This tutorial will show you how to install my tunnel and portal system. In Surveyor, switch to 'Wireframe View F9', and begin by laying a section of track through the area where you wish to install the tunnel. Make sure that 'Fixed track vertex height' is checked in 'Options".

At this point, you may wish to add some type of tunnel track as shown in the picture below. Next add 'Dig Holes' at both ends of the tunnel (I use Dig Hole, Kuid2:69518:1999:1). For double track, you'll need two at each end. Move the track left or right, so that it is centered through the dig holes

Next, open the 'Objects-Add Spline' tab, choose one of my portals, (double track in this case) and install it, starting inside the terrain and dragging it to the outside.

Now, take the elevation at the front of the portal, and apply it to the spline point at the rear, to level it.  Move the front of the portal back until it is just covering the dig holes, as shown in the picture below.
Install a portal at the other end of the tunnel in the same manner. Bring the tunnel track to the face of the portal

Undo Wireframe View to view the result below.
Open 'Topology', and select 'Height Down'. Select the smallest diameter radius and the lowest 'Sensitivity" dial, and start pulling the terrain down until it disappears below the top of the portal roof. Do the same at the other end. You should get the results shown in the picture below.
Now it's time to install the tunnel. For double track, select 'Tunnel 2 Track' (Kuid73500:100079). Attach it to the rear of the portal, as shown in the picture below, and drag it to the other portal
The final result should look like the picture shown below. Be sure to adjust the portal and tunnel height so that it is below thw track ballast.

That should complete the installation. Run a test consist through the tunnel to check for any terrain that might be protruding below the portal roof.

If you wish to install a curved tunnel, the track will seek its own radius, however, it might be necessary to add a couple of spline points to the tunnel to center it on the track. This can be easily done in Wireframe View.