Here you go.
Basically this started because I needed an Nn3 test track as I've been building Nn3 Climax A's as one version of my kit as custom builds. So they really have to be run and tested.
So if I needed a test track, well, may as well make it a Ttrak module. IF, and IF, I could figure anything out that fit. There was a very small lumber mill at West Hickory that had a Climax A, only lasted for a few years, was wiped out by a flood. McCabe Lumber. So when I discovered I could JUST BARELY get a circle of Rokuhan 4 1/2" radius in there as a loop, I was off and going as another logging railroad module concept.
I tried Mark's (narrowminded's) Code 40 on tie strip only to discover that Pliobond to hold the rail deteriorated the ties after a year, it looked great while it lasted. Tore that all up and redid it with Marklin sectional on the interior on cork, two Marklin curved switches. One Rokuhan 'medium' turnout on the main, and a Rokuhan "medium" that I added a third rail to to make it dual gauge. So that siding (third track in) is actually dual gauge, and it works.
But yes, you can get an oval of Nn3 in on a standard T-trak triple, and yes, it works. This is a pretty general track plan too. I'm trying to fit it to a mill on the left and an enginehouse on the right. Runs quite well with my little Nn3 Climax A's. The track to the rear is literally hanging over the edge, had to cut a hole in the skyboard to get that additional 1/4", that will kind of be a hidden storage track in the hill and trees. Pond and feed stream is cut, but scenery is a ways off, let alone the scratchbuilt structures.
Note that I paint everything, including every visible piece of the Rokuhan sectional, rail and ties.
link:
http://www.randgust.com/McCabe%20module%203.jpgThe mysterious toggle in the front solves a problem. The dual gauge shares the one rail, and if I don't want power leakage from the Ttrak in the future and still run mine independently, I have to be able to swap that rail over between my local control and the inner Ttrak line (that may even be DCC).