In the last few days I have been going through some graph paper in working out some designs. Solved the aisle space problem by going back to a initial idea I've always had floating around in the space between the ears. Essentially I have gone back to a shelf style layout design with shelf widths varying between 30 inches and 36 inches. The mainline curvature is not less than 16 inches and not more than 19 inches with a total of 68 feet of mainline running. The only locations of 16 inch radius is in entering and leaving the town of Lyle. The line is a water level route with no grades. The logging and mining branch will have approximately 40 feet of mainline with grades not to exceed 2% only in the climb up from Lyle. The layout will have two levels but not in the ordinary sense and design of a dual level layout. The area modeled along the Columbia River has steep rises of 300 to 500 feet and more not far off the riverbank where the mainline runs in the area being modeled. The upper level will be on top of this with the mainline down following the river. A number of places those rock outcroppings run to the river thus there are quite a few short tunnels which gives me places where the upper level can widen out for log camps etc. In another concession to having gimpy knees etc. I'm going to set the heigth of the lower line to a comfortable chair heigth. Probably 36 to 40 inches, If I want I can just set and watch trains run and switch the town of Lyle from some level of comfort. The upper level will be just below eye level probably about chin or neck level. Inside corners will rounded and be void spaces keeping everything within decent reach of 30 to 36 inches. The layout is being designed to fit in a 12X12 foot room and using the shelf concept around the room gives me a lot of open space in the middle for a small work space. I'm still working out the logging and mining branch track layout but here I get to play with 9 and 3/4 radius. All the tunnel portals will be double wide even though a single track runs through them for the most part and a little higher than normal in case I end up having to go up in scale to HOn30 because of the eye issue. Another issue with the tunnels, which I think I have a handle on because although numerous, they are all short and in accessible areas. I plan to make liberal use of rerailers in the tunnel areas. I have been able to get a harbor/port area into the design so the river and coastal craft will get used.
Doing a reality check I've had to make a number of compromises and just flat give up some things. The Broughton Flume and sawmill is one of them. It will be modified for a small mill in Lyle. The Chinatown module I built back some time ago cannot be used and will most likely end up in a display case, or maybe cut into smaller sections, and the largest turntable will be the Atlas model with a single stall engine house. Fortunately a number of my structures are smaller in size and may be able to fit up on the branchline so the branchline may get a brewery located on it. But unless I get ahold of a nice basement along with the new digs where I can add some footage to the Lyle area probably about 50% of my structures are going to end up being surplus. And of course the narrow gauge is history both because of the vision issues and because there just won't be room for it.
One of the other things I scrapped for now is the idea of a staging yard. It ate up too much space and I don't want anything under the layout with the inherent problems of getting to it. What I may end up designing is a portable staging that can be rolled out of the way, or even out of the room, and can be connected by a single track to the main by a narrow hinged bridge. Probably not more than 24 to 26 inches wide so it can be rolled out the door if needed.