Designing Roadblock

 Planning is never a waste of time. I wish you had shown where the doors are in your diagram because looking at this it looks like you enter from the end. Your walkway is barely a foot wide if each square is a foot wide which would be a problem for me. I also think you have to be able to reach most of the track yet some of the distances seem like a long reach. If there is a man door at the side I would try to put the layout at each end in a dog bone design and be sure to give yourself some room to look at and photograph your trains. Parallel tracks could be on separate loops and would be exciting to watch.  Best of luck.

I have another thread that better defines the space and should have included a link, sorry about that. It is a large table with 2 access hatches. I'm trying to find a way to eliminate the hatches and still get 3 independent levels in. This space is the left stall of a 3-car garage, so there is no entry door per se. The door to the garage is off to the left opposite the aisle entrance at the top of the layout, it is 6" away. There is a 2' strip along the lower left side, 2 more stalls on the top and the garage door itself is on the right. It will have to be open to access that side, but since I live in Phoenix, that is not a problem. The reason for the open space in the upper left is for access to the rest of the garage.

As I said, I know the aisle is narrow, but it's only meant for access, not "walking". It is 13" at the narrow point and the center is 24"x54" in the center. The longest reach is just over 36" on the right side of the center, so I don't see that as a problem. Both the narrow part and the center will get adjusted if I think further work on this type of design is worth pursuing for this space. I laid it out using card tables and I can easily get through the 13" aisle, so I'm not concerned about that.

If I do pursue this, I'm going to consider a swing-out crossing the aisle so I can eliminate the upper reversing loop and widen the aisle/center to make it an actual walkway. I already have a design for a 10x21 space that uses O72 curves on the mains and two semi-hidden O31 reversing loops that I can adapt, but I am trying to see if I can design something for the space "as is" using a loop-to-loop configuration. Given that the 2 loops take up so much space using O54, I'm having difficulty figuring out how to add 2 more levels while keeping the grades below 3%.

The bottom line is I don't think I can do what I want as I've defined it, but there are some talented people here who might see something I don't. Or they might have some ideas how to better use the space even if it means I'll have to forego running 3 independent trains. While that is my goal, it's not a hard goal. I "see" what I want to do in my mind and it would be no problem if I were using HO-Scale, but I'm having some difficulty "squeezing" things using O-Scale. All I've seen are large club layouts, so it's hard to envision operations on a smaller layout. If I could watch someone operate in something close to 10x17, I might have a better appreciation for what can be done and I might be able to scale back my desires.