If you are going to punch a hole through a wall to extend your track, you should check a few things first.

First, make sure that you won’t be cutting into anything that may be hidden within the wall, such as a stud, pipe or wiring. I would recommend drilling a small pilot hole (1/4″ in diameter) in the center of the area you plan to excavate, just deep enough to get you through the wall board or plaster, maybe 1/2″ deep. The idea is to keep this hole as shallow as possible so you won’t accidentally drill into a hidden pipe.

Next, take a piece of coat hanger or stiff wire and bend it into an L shape about six inches long on one end. Stick the six inch end into the 1/4″ hole and try to work it in so that you can twirl the end so that it acts like a probe behind the wall. If you can rotate the wire 360 degrees without hitting anything, it will probably be okay to begin cutting. If you do hit something, you may have to move the proposed hole location left or right until you get clear of the obstruction.

On the side of the wall that has your layout, measure up from the floor to the underside of the existing table. This measurement will determine the lowest part of the opening you’ll be making. Next, draw the outline of the hole you wish to make. The size will be determined by the scale you’re using as well as how many tracks you’ll be running through the wall but add another 1″ to each measurement to allow for some ‘slack’.

Using a saber or keyhole saw, cut through the wall board or plaster on both sides of the wall. After the hole is cut, I would recommend getting the inside measurement between the two walls which will probably be about 2″ to 3″. Cut two pieces of scrap lumber the same width and 3″ or 4″ high. Using glue or screws, attach these two pieces to INSIDE of the hole on either side where the track will go. The purpose of this barrier is to prevent any rolling stock that might get derailed from falling in the void between the two walls.

If the hole is going to be hidden from view, I would just run your roadbed and track through the hole to to the new area/section.

If the hole is going to be in view, I would just mount a normal tunnel portal and add scenery as if the track were running out of a hill or mountain. You obviously could do this on either side of your wall if you wanted.

Hope this helps,

Geof