Mammouth Gulch

Just west of Tolland, the valley once again narrows into Mammouth Gulch. Here, the trains actually disappear into the trees, before crossing over both East Portal Road and South Boulder Creek.

Mammouth Gulch Area. Photo from Google.

Approaching the Mammouth Gulch Bridge from the east in June 2014. Photo by Cameron Turner.

Looking back at the Mammouth Gulch Bridge from the west in June 2014. Photo by Cameron Turner.

At this bridge the tracks and railroad literally jump back into view from the road. From here, the trains are almost upon East Portal, leaving very little chase remaining before the Moffat Tunnel. I wanted to model this bridge, but I also needed separation from Tolland and East Portal, and the track will pass back through the doorway here, which meant that I had the upper limit of the doorway to negotiate.

Mammouth Gulch LDE Plan.

The resulting plan made use of my loop trick a third time, but this time I used it to gain elevation. The track leaving Tolland crosses through the doorway at 48.25" above the reference elevation. If the reference elevation (Prospect Junction) is set at 30", this places the height at 78.25", which will give me a little more than 2" of clearance through the door frame - enough for N-scale and without requiring any work to the door frame or its header. This is also well below the 96" ceiling height of the basement.

The plan calls for the tracks to disappear into trees as they approach the door frame. From there, the tracks turn left and loop around the helix, gaining height on the first lap to achieve a height of 50.25" at the cross over point. A second lap is made to extend the run at this elevation and the track then loops back out onto the visible layout, once again appearing through the trees, onto the fill and across the Mammouth Gulch Bridge over East Portal Road. The crossing of South Boulder Creek is through a culvert in the fill. The train reaches the east switch of East Portal Siding at an elevation of 50.25" above the reference point, or 80.25" above the floor. This section has a grade of 1.26% during the climb.

The combined effect of the double loop is to make the distance between Tolland and East portal approximately 40 feet or a about 1.2 scale miles. In reality, the distance is about 3 miles by rail. Nonetheless, this is sufficient to space out the two sidings in the model by several train lengths. Unfortunately, 29 feet of that run is hidden track, but then again, the railroad does disappear from the road between Tolland and East Portal. In operations, there will generally be about 1 train length during which the engineer will not have direct sight of the train (either the locomotives or the trailing end) during this run. However, the alternative would be to have the two sidings effectively next to each other where the train would be leaving one while entering the other.

One possibility it to eliminate the second lap, which would shorten the distance by about 14 feet, or one train length. However, I think at this time that I will keep the extended run, and could envision implementing a signal or camera system that would allow the operator to see their train making progress, and could even envision introducing some scenery to the area to provide for better continuity of operation for the engineer.

Cameron Turner