Choo Choo Charlie said:
" . . with multiple loops can be interesting to watch for an hour or so."
Particularly if designed to provide lots of variation. I spent alot of time planning my layout for this, so that " routes vary and trains meet" and it's just fun to watch for long periods, and I deliberately did this so I use few swtiches. I have three loops with a little less than 300 feet of mainline track, using this strategem:
- the outer loop (141 feet of track) loops around the layout and has no switches at all, it goes over itself and loops back around once, then down and inside itself again. It has no switches at all: the train on it always goes the same direction ut comes around any viewer twice per one orbit of the loop.
- the second loop (75 feet of track in a twisted dogbone with switched reversing loops at each end for a total of 103 feet of run each lap) is inside that outer loop. A train on it changes direction with each orbit: last time you saw it it was coming left to right, not its right to left, etc.
- the third loop (64 feet of track in an over and under dog bone with unswitched reversing loops - the common (two way) portion of the "bone" is a guantlet track - is inside that second loop for about 74 feet of travel per orbit. Unswitched reversing loops at the ends mean although the train reverses, except for the common truck of the dogbone, it is always going the same direction around the end loops.
The result of this pattern of two dogbone-reversing loops inside one that is not reversing, all of different lengths, means that trains meet and pass one another at different times in different patterns as you watch. Not a lot of repeition and lots of surprises. Its fun.
The result is near-unpredictable patterns of trains coming at you wherever you stand near the layout: with three trains running.
- you see the train on the big loop twice per orbit because its over and under itself, always going the same direction.
- you see the train on the second loop once per orbit, but the switched reversing loops mean it comes back at you the other direction each time. Also, it passes the train on the outer loop in the other direction each time.
So anywhere you stand to watch, there is a lot of variation in what you see coming at you, watch passes what, where. Never the same thing over and over and over. This makes it fun - at least for me.