Modular Layout

Build a Portable Model Railroad...

No space for a permanent layout? Constantly moving? Or maybe you're looking for a way to share the hobby with others.
Sometimes the model railroad that moves us moves with us. A portable model railroad can be a great way to take your hobby on the road. And a railroad doesn't have to be huge to offer big rewards.
You don't need to have continuous running options to have hours of fun on a model railroad. In fact, with this method you are able to run the train endlessly through the Automated Reverse Loops, but thinking about its every move and job is a great way to lengthen your modelling enjoyment. This shelf-style layout represents a typical small station with a "fiddle yard" and provides a lot of operations in a relatively small space.
Although the "mainline" on this railroad between the two loops is only 1.2 metres long, you could easily stretch this plan into a larger shelf-style layout around the walls of the room to provide a longer run and even more industrial switching action.
A small train of only a locomotive and two cars can keep you occupied for quite a while on this deceptively simple railroad.

Track
This track plan is designed around standard code 100 track sections.

Wiring
As the entire railroad would be one operational block, conventional or DCC systems could both be used to power the line.
A DCC system would allow you to easily add a second locomotive to make your own operations easier.
A power bus with feeders to the many sidings will allow reliable operations through the many switches.
The number of feeders you install is up to you, but at least one pair on each of the three long tracks of the yard would minimize voltage drop issues.

Scenery and Structures
As a portable layout, scenery is a bit of a challenge. If your interest is primarily in operation, and you move the layout frequently, then minimal scenery may work best. Simply ballasting the track and adding some ground cover will go a long way towards providing a finished look without adding much weight or any delicate parts.
If you do choose to add structures, background buildings will work well. You could use kits as-is, or do some kitbashing to fit and make the most of materials. Walthers and others make many industry kits that can be easily modified for these scenes and stretched along the backdrop.
With sidings branching off in different directions, switching even a two-car train could take a while.
Uncoupling magnets could be added, but given the small size of the operation and the many places you'll want to separate cars, you may be better off using a hand tool.

The main module to be enclosed in a wooden box 
with removable plexiglass top and front panels, 
a photo realistic backdrop and neutral white 
LED lighting...

The control diagram.

Simplified wiring diagram...