one-of-issues-with-trackplan-is
One of the issues with the trackplan is the reverse loops and DCC. There are circuits available that will automatically handle the reversing, and I'll need three of them. The red, blue and green blocks on the layout schematic below will each need reversing circuits. The way they work is by sensing the short circuit that occurs when the metal wheels of the locomotive arcs a gap cut in the wheels. When this is detected, the polarity of the block is reversed. Because metal wheels are key to this system, the block needs to be longer than the longest train, or you need to keep plastic wheels on all the cars. There is a lot of people who say that plastic wheels build more gunk on the tracks and insist on metal wheels for all their cars. I think this makes the train sound like a Pachinco machine rolling down the track. Even so, the shortest block is 14 feet long, so even with metal wheels, I can handle a 14 foot train.Counting the black block, I've got four power districts on the layout. There are circuits available that let me take one power supply and divide it into four power districts. This is great for the reversing circuits and also means that a short circuit won't cripple the entire layout, just the effected area.
As this graphic shows, I've adjusted the trackplan to angle the area near Summit and Silverwood. This was necessary to allow access to a cabinet on the back wall and to shorten the Mormon Rocks leg of the layout. As it turns out, this made a more prototypical depiction of Summit.
The power districts caused me to think seriously about signals for the layout. Automatic circuits are available to create a prototypical signal operation based upon the power districts. That would have required many, many power districts and I've decided that based upon my style of operating, I'm going to use a simpler signalling system that relies on sensors between the rails. When the train covers the photocell the signal turns red. When the train clears the photocell, the signal turns yellow after a delay (either 10 or 30 seconds). After another delay the signal turns green. The system I'm looking at is by Logic Rail Tech.