Hinged lift bridges are a necessity for advanced model railway layouts to allow easy access to all areas of the layout. Building a hinged lift bridge for a model railroad setup is a fairly simple process, but keeping it working smoothly for years takes a few extra steps. Extra attention to detail and a few inexpensive upgrades will give you a bridge that works right and keeps your model trains on the track, not on the floor.
Saw piece of plywood long enough to bridge the span and wide enough to hold tracks and fencing.
Glue the track pieces to the piece of plywood.
Attach hinges to one end of the plywood, on either side of the tracks by screwing them in with the screwdriver and screws.
Screw blocks of scrap wood underneath the train layout base on both sides of the span with a small lip, about 2 inches, projecting from the base. These will act to support the bridge when it it is lowered into place. If necessary, glue shims to the blocks to ensure smooth operation and firm support for your bridge and track.
Screw the other ends of the hinges onto the top of the base of the train layout. The bridge should now lift and lower back into place.
Connect a power cable to the base on the hinged side of the bridge and connect it to the track to supply power, leaving enough slack in the cable that it won't be damaged by the bridge raising and lowering.
If the bridge will be raised often, attach a hook-and-screw lock to the far side of the bridge and the base on that side to lock the bridge in place when not in use. This will ensure the track remains connected to the track on the far side.