Mark, I think you need to test climbing ability to check on the max grade with your worst engine WITH a full load. (Easiest on the floor imo...tell the knees I'm sorry ) You also need about 6" clearance from rail top to roadbed. I don't see that yet.
I was surprised when on the ceiling, mine ate up 12-15ft one way to get to 7" ( partially extended pantographs). It is straight though, a curve may give more traction as the flanges hit... Oops, flat rail..no tellin'.
My point is test and test again before committing to a grade permanently.
I used two tressels sideways, and a beam between them for the track to sit on to get around my ground level tracks directly below the El on the table layout. Offset, even wider at about 5". I got the idea from a real El (NY I think)
You could cut the foam up for now, lay a paint stir, ruler, etc. across them for tests and carve and paint it or send dimensions to Mike for a more solid piece.
Butch, Good thinking!! I wonder where I left my brain since I first came up with this idea!! I did all that figuring maximum grades for the Blackwater Canyon Line, but left those thoughts on the shelf once I started this little project. Fortunately, I'll be running short, light LionChief Christmas trains, Polar Express, Hallmark Toymaker, and Hogwarts too! (While I'm not much into Harry Potter, my daughters are, and I do like the Christmas scenes in the movies) The trouble is, those engines are weak pullers.
I think I can play around on the carpeted tabletop instead of the floor, since my legs are in a bad way and the little terrier dog is a train terror! I actually saw your post last night about 2 or 3 o'clock in one of my house ramblings trying to get the sciatic to settle down.
Since it rained overnight, I'll have to see if things dry out a bit before I tackle fallen leaves. My sister is taking Dad to a hearing aid doctor and they and Mom will get lunch out, so I won't go to visit them either. All that to say, I may get some time to try to work this out before getting back to our gracious friend, Mike!!
Thank you again!!