Dear Mark:
I changed the curves to a minimum of 42 diameter. Your baby will work! :-)
The passing siding curve is a 48 diameter. Since we increased to 42 as a minimum a reversing loop at each end became impractical because of everything needing to be with a 30 inch maximum reach and people space.
I discovered that my "Wye" suggestion also became impractical because of aisle way widths. The turnaround "solution" is a 24 inch turntable. Atlas does make one that size that is inexpensive. However, you will need to "weather" it well. I placed turntables at both "ends."
There are three lanes leading to the turntables on both ends. That means you could have another train or two (might be pressed for space) on any of the "free" spokes. Another advantage of this arrangement is that it will allow an engine to get on either end of a train so you may easily "classify" (arrange) your loads/empties in Davis or Hendricks. There are staging drawers at both towns. And you will need to switch the caboose from the front to the rear of the trains at both locations. Talk about realistic!
At Davis, 60 inches off the floor is high for a turntable in my opinion. Maybe not in yours. You may want to consider the height of this layout. I have the bottom at 41" and the top at 60." I wanted a dramatic difference to illustrate the steep grades and sharp curvature.
You may maintain that same grade by "adjusting" the entire profile. I mean make the top of the layout 55" up and the bottom 36" from floor. That 5 inches will make a world of difference in Davis as it will be easier to reach the rear track which is 28 inches back from the aisle way. At your height, you'd be okay at 60" but it may be a stretch. I'm 6'2" and I'm stretching at 60 inches high to reach. TEST YOUR REACH AT DIFFERENT HEIGHTS.
Whatever you decide, everything, that means EVERYTHING must be within 30 inches of reach, and less is better. As layout height increases your reach decreases. And factor in there are two lines of track in front of the rear track at Davis. You would have to reach over to fix a problem. You would need a step ladder/stool.
I have multiple step stools at my layout. As we clean track or install scenery we need to reach over trees and buildings at times. Those objects "reduce" (restrict) your reach. I have library rolling stools which are also a step. These are great because you can sit at Hendricks, stand at Davis and roll this library stool anywhere you need it to be including out of the way.
This track arrangement is fantastic for operation as trains pass each other going up and down the canyon. I can "picture" two Operators running the line. There would be four trains total. Two trains in Davis and Two in Hendricks. The first two would start, one each from opposite ends, and "meet" in the canyon. When they arrived at their respective towns for water and coal, the crew would switch to the other train, already standing by, and make their return trip to "home" and finish their "trick." If a third person was there, he or she, could "stage" additional trains or remove already used rolling stock to the staging drawers.
I suggested the "bare bones" of this theme and operational plan. You may have a better idea for a spur along the way or a different track arrangement at either town. The turntable at Hendricks is pretty much stuck where it is because you will want to maintain a 36 inch wide aisle way. It isn't worth one or two more spoke tracks to store an engine because your people space is at a premium! You and any one else viewing or operating the layout is far more important than one spoke track.
I think this is a great theme and good for the space. If you go with this, you will have to very carefully plan the bench-work. If you don't have it buy Linn Westcott's "How to Build Model Railroad Bench-Work." USE THE L-GIRDER method. This layout is ideal for that support system.
Also plan to include BACKDROPS. You will need them to make the BCL awesome. You will want to curve your backdrops around the corners of the room. It will make the layout look far, far better than square corners. Hardboard works very well.
I would also recommend you extend your backdrops all the wall to the ceiling. I would paint the ceiling a very light sky blue. Think about your lighting prior to constructing all of that bench-work which will swiftly become an obstacle.
I will attach the revised larger curvature diameter plan tonight; which includes suggestions for the "ends" of the line.
