My march up Salt Creek canyon filling in the basic landforms arrived at Tunnel 10. This tunnel has rock sheds on both ends, with the RR-West face opening out on Noisy Creek Trestle. Working RR-West from Tunnel 12, I created a rock wall face base on one side with the other side falling off toward the creek. I will return to this area with rock molds. My terrain covering the tunnel has a very steep fall-off into the creek forced by the proximity to my Wicopee siding which loops inward--toward the wall and the Tunnel 10 track, pinching the terrain near Tunnel 10. I will need to apply more rock work to this area, as I wanted to retain the creek down in what became a gorge.
RR-East approach to Tunnel 10. The gray slope above the track will become a rock face with rock molds applied. Similarly, the steep gray terrain slope on the left forms part of a gorge. Wicopee siding and main show in the lower left corner, forming a very narrow strip between Wicopee below and Tunnel 10 on the upper line. The track connects behind the camera via Salt Creek Trestle.
Working with tunnels, I first establish the terrain line along the wall (backdrop). Next, as with Tunnel 10, I establish any support system in front of (closer to the aisle) for the terrain. I then find it best to establish the terrain at the portals. Finally, I fill in the terrain over the rest of the tunnel. For tunnel 10, I needed to create the gorge with its steep slope and the RR-East approach with a much shallower slope. Geologists will be amused by my terrain shaping, but this is part of the art of model railroading--creating an effect or appearance rather than fully modeling actual terrain. Consider that as the art of compromise. It must fit within hard physical boundaries with the railroad taking priority.
Creating the terrain for Tunnel 10. A terrain profile slab of foam has been attached to the wall (backdrop). A front terrain form (support panel) has been installed in front of the tunnel. Slopes for the tunnel portals and rock shed extensions have been installed. Finally, the ridge terrain is taking shape with panels spanning between the rear (wall) terrain form and the front support.
Once the rough terrain shape was formed with pink foam panels, notable gaps were filled with spray foam insulation. All of this was then shaped using knives and a Surform ™scraper. A couple of treks through the kitchen section of our local Goodwill store netted some good tools for terrain forming.
Tunnel 10 and RR-East approach terrain formed and spray foam insulation applied to cracks and joints.
Tunnel 10 terrain shell formed and shaped. I added a knob to the steep panel face forming the tunnel side of the gorge. This helps break up the expanse.
Finally, I spent three and a half hours mixing and applying Sculptamold to the foam shell. This session covered the Tunnel 10 terrain and completed the lower section of the Salt Creek canyon leading to Salt Creek Trestle. As with prior terrain forming, I mix latex house paint in with the Sculptamold so there is a base color for any chips or dings. It also provides immediate color without the "snow effect" of the basic white Sculptamold. I used a tan color for earthen areas and a gray for areas representing rocks.
Completed base terrain for Tunnel 10. The gap below the track and rock shed on the left will become a scenery access hatch.