Finally decided to add a 'round the ceiling loop to my 12' x 12' train room. Of course this would have been a whole lot easier if the layout wasn't already there, but...
Here's the start - I cut a 3 1/2" wide 3/4" plywood loop that will be cut into 4 quarter curves, connected by similar strips of straight track. Those will be easy after cutting the donut for the corners. Used a router with a board attached to cut the circles (like a compass).
I'm using O-27 track, with 42" curves at the corners... just a basic square with rounded corners (unless I decide on a passing loop on the back wall)
The supports will be brackets similar to the ones pictured:
Thoughts or suggestions greatly appreciated!
Ed