I built a plate girder bridge to span the space between the module and the main layout. The bridge also provides DCC electrical through-put from the layout to the module. The first order of business was to cut a hole in the Masonite board side panels I use for my layout. The location and angle was a bit difficult to cut, so it is not perfectly square, but there's enough for clearance. I plan to camouflage it with trees and bushes later on. The bridge not only connects with the module, but more importantly it provides the second leg for the run-around track that ends at the turnout shown in the photo below. Without the bridge, two engines are required to do the switching in this area. The bi-fold doors of the room's closet are visible in the background.
The bridge uses some Radio Shack 1/8" mono phone plugs, so the matching jack was installed in the 1/8" thick Masonite. I dug out some scenery base and installed the jack so that it is hidden later on. It fit perfectly, with plenty of space to grip the jack with the nut. I then soldered the DCC bus wires to the appropriate connection points on the jack (you'll need to test with a multimeter to find which one connects to which part of the plug).
The next photo shows the plug-in side of the jack. I also installed some rail joiners. These are just to make sure the bridge's rails line up. I made some oak blocks to hold the bridge up. A small block is glued on the side to prevent the bridge from sliding off of the block. Although I measured as best I could, I was still off by some, so the strip wood and styrene pieces are needed to have the top of the bridge's rails line up with the layout's rails. The bridge is removable, so all I need to do is slide the rails into the joiners, and plug the plug into the jack, and I'm ready to go.
Once the block on the layout side was installed, I could work on the module side. I used some temporary blocks and a clamp to get the oak support block at the correct height (using a small level on the track to make sure the bridge was as level as possible). I put a piece of ceiling tile on the module, and a typical tie on top of that. This gave me the height of where the bridge's rails should sit. I could then drill holes into the oak block and screw it to the module.
The next photo shows the bridge's plug plugged into the layout's jack to provide power to the rails of the bridge. This is on the back of the bridge, so it is not visible from the normal viewing angle of the layout.
With the bridge finished, this is the view from the layout to the module in the closet.
My layout is now two feet bigger!
When the bridge is not in place, I put these Hayes Wheel Stops on the rails. They prevent an engine or car from taking the dreaded fall. However, in practice I have the bridge installed all the time. I even took one of the bi-fold doors out. The bridge really adds to the operation of the layout.