20 Scenery Demonstration
Prior to the demonstration the excavating team for the ATSGRR worked hard to construct the part of the mountain above Sulphur Gulch. The mountain was deliberately left in stages to show the whole process. The first photo shows this section of mountain.
For those with a technical interest the remainder of this post gives the blow-by-blow description of the construction process. The following are the steps in the process.
1. Before the construction of nature can begin complete the infrastructure for the surrounding area. On the ATSGRR this consisted of completing the trackbed for the high line at Echo Junction, the trackbed leading from Echo Junction to the top of the helix to return to staging, and the trackbed from Echo Junction across behind the helix to Park City which is located above the workbench roll-top desk on the other side of the helix. It was also necessary to complete the protective barrier around the outside of the helix to prevent trains from accidentally jumping to their destruction inside the mountain.
3. Place cardboard strips to create the contour of the mountain. They are held in place with hot glue and a couple of support posts inside the helix. The mountain forms a shell over the helix that is open in the middle so that someone can stand inside the helix when repairs are necessary or an accident occurs. The top of the mountain is above eye level so that spectators cannot view the inside of the helix even though the top of the mountain is open.
5. Paint a soupy mixture of plaster of Paris onto the cheese cloth forming a thin plaster shell when it dries. In places subject to strain or possible bumping from tourists paint several coats of plaster to form a more rigid shell.
6. Make plaster castings from rubber molds formed over real rocks. When the plaster in the mold is still damp but not yet set firm press the casting in place on the plaster shell. The castings can be forced into indentations in the shell to form small canyons as shown in the picture.
8. After the rock castings are dry spray them with a mixture of wet water (water with a drop or two of detergent added) containing a few drops of India ink. This flows into the cracks and crevices of the rock to make them more apparent and to form shadows.
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10. Using earth colored pastel chalks dry brush various colors onto the rocks to form more variety in the color. Go easy as too much color does not look realistic. When the cliff looks like the real thing spray a dull coat matte finish over the work to keep the chalk from smearing.
11. Complete the scene by applying a coat of diluted white glue over the painted surface of the ground and sprinkling on fine ground foam (The ATSG uses Woodland Scenic Products) in appropriate colors for the area and season being modeled. Add shrubs from clump foam and plant trees as appropriate.
For more information about water based scenery consult
Dave Frary -- How to Build Realistic Model Railroad Scenery 3rd Edition
http://www.kalmbachstore.com/12216.htm
For more information about cheese cloth scenery consulthttp://www.ucwrr.com/Kelly%27sScenery.htm