With the basic benchwork support erected, the next task on the mountain grade was to form the subroadbed. I am using a combination of plywood and hardboard spline. I have space for the “company village” (operator housing and section crew) at Cruzatte. The housing and support structures need a base, so it seemed a good use of plywood for the entire siding scene. For Wicopee, I used plywood for the end switches and the company spur, connecting the ends with spline. Spline is used for the rest of the mountain grade.
Mountain grade benchwork on the left and in the distance. Cruzatte siding is on the plywood on top. Below is the spline for the grade up to Wicopee. The lower level will duck into Tunnel 20 to get under Cruzatte. The blue tape on the floor in the center of the picture marks the edge of the operator platform that will be on the left for the mountain grade.
Each of the three trestles on my mountain climb (Salt Creek, Noisy Creek and Shady Creek) has a plywood base well below grade. The base will provide support for the trestle towers and clearance for scenery sculpting. Eventually, each trestle will have a spine made of aluminum strap (two 1/8 by ¾ inch straps separated by 1/8 inch spacers) with the bridge girders fit around the spine. My friend Richard C. rolled and formed the aluminum strap for me. Unfortunately, I had not yet planned the Shady Creek trestle. I actually built it (formed with spline) as an S-curve. The temporary spline will stay in place until we can rework the spine. Note all three trestles have curves running through them.
Initial mountain grade roadbed spline with Shady Creek Trestle on the upper line.
I needed temporary risers for the trestles with height adjustment ability. This was done by cutting through the basic riser with a 45 degree cut and then splicing the adjustable riser at the desired height. Doing this in the middle of a curve required an offset reference point which was provided by a combination square. I employed this technique for both Shady Creek and Noisy Creek.
Setting the temporary riser heights for Shady Creek trestle. The long level simply provides a good straight grade reference. Adjustable riser inspired by Jerry B.
The “main event” on my mountain grade is the Salt Creek trestle. This forms the turn back loop on the mountain grade. It is a signature scene for my layout. Indeed, photos taken at Salt Creek trestle serve as the background for this blog and as the inspiration for the railroad. I decide to leap in from the beginning of construction and build the connecting roadbed around the ends of the aluminum strap spine. I was able to accurately cut the riser heights, so the temporary risers are simpler than the ones used at Noisy and Shady Creeks.
Salt Creek trestle spine mounted with connecting roadbed spline formed around the spine ends (clamps are on the hardboard spline).
Roadbed spline formed around the trestle spine. The aluminum trestle spine has been painted black to help disguise it inside the eventual bridge girders.
I now have the core roadbed spline connecting McCredie Springs on the lower level to the roadbed descending from Cascade Summit. The mainline roadbed is very nearly complete!