Section 12 - Tunnel 1 - Part 2

In the last blog (Section 12 - Tunnel 1 - Part 1) I identified the layout design elements of the Tunnel 1 Section and laid out the roadway lines. 

In this blog I am identifying the scenery construction concept and laying out the landforms.

Scenery Design Considerations

Background.

Sky, Clouds. There is 1 backdrop 22 inches in height. It will be a simple backdrops- a clear blue sky suggesting a sunny day. 

Landforms  

Ridge. The terrain at the North Portal will be consistent with the Polson Canyon ridge line. There is a more moderate slope along the east face of the ridge. 

Here is the generic photograph of the southern part of Polson Canyon as it approaches the the North Portal of Tunnel 1.  

On this section, I continued the construction of the Polson Canyon ridge line with the 2 inch styrofoam. The ridge should be at least 3x the height of the train to provide a reason for the curvature of the main line thru the river valley. Using 2 inch styrofoam insulation, this would make the rock faces at least 7 inches high with the maximum height of 11 inches for the ridge at the rear of the section.  Additional height of the ridge can be painted on the backdrop.  See 5.5.6 Mountains and 5.5.5 Rock Faces for construction details.

Saddle

The tunnel is sited through an enlarged saddle with basalt rock walls on both sides. The possibility of rock spalling due to steam engine smoke stack exhaust requires timber tunnel lining. No additional engineering is required within the tunnel area. 

Tunnel Portal The terrain at South Portal will be a basalt cliff face with a concrete portal. I will use 3/4 inch styrofoam and hydrocal plaster to model the rock shelves and will use matte medium and modge podge for the waterfalls and creek. See xxxxxxx for construction details.

Embankment. An embankment with a dry creek bed comes down the moderate hillside to the eastern river riverbank. Again, I have selectively compressed the AREA standard 60 degree angle to 45 degrees from the edge of the roadbed to the river bottom. This allows a greater river bank edge along the fascia. See 5.5.3 Embankments for construction details.

Waterways

Creek.

Several streams and dry creekbeds will drain from the ridge line toward the river meandering along the the fascia.

Once the basic land form as completed, it will be covered with Sculptamold on the flats and hydrocal plaster on the slopes. Flat areas will have some degree of undulation will be covered with sculptamold. 

Ground Cover

1. Far ground cover on hills and ridges will be modeled with teased and dyed felt. See for construction details.

Near ground cover along the right of way will be a variety of dead, summer and early fall grass colors.

Vegetation

The hill and ridge land forms will maintain a denser growth of second growth conifers, dead trees, stumps and bushes, indications of previous logging activities 

The embankments will have a heavy growth of shrubs and bushes, with growth along at the river's edge. See 5.7.1 Shrubs