There are many different ways to build retaining walls for your layout or diorama. Perhaps the easiest is to go out and buy one
that looks appropriate for the place where you want to put one; then incorporate into your scenery. Chooch Enterprises, Inc. makes an interesting flexible retaining wall that may be just what you need. However, some model railroaders have become quite creative in developing their own walls.
Natural walls and cliffs
I like to create rock walls and cliffs that tower on either side of the track. This simulates a natural type “retaining wall”, which works well for rural areas, but obviously not for cityscapes.
First I develop the mountainous terrain. Then on one side of the mountain near the track or road, I build up the cliff or “wall” using Sculptamold. I usually use an old spoon or a small trowel to spread it out, making irregular ridges in the wall before it hardens, to make it look as much like rock walls that have been cut out of the side of a mountain as possible. After it hardens, I then just paint the wall in a spotted irregular fashion with a variety of washes in the same manner that I paint regular Hydrocal rocks that come from rock molds.
Many model railroaders like to use other materials for their rock walls like stacked, broken or cut ceiling tiles, or stacked cork tiles or even chunks of cork glued together. You can always use Styrofoam sheets stacked vertically or horizontally and cut or roughen up the edges as much as you want. I've even used pine bark mulch from the garden stacked on top of each other to create natural-looking walls.
For more of a man-made look, you could use scale-sized wooden railroad ties stacked up to create a retaining wall. You could also use a plain sheet of Styrofoam packing material, cut to fit, and paint it a cement color for your wall. Or for an even more realistic look, use real Portland cement or QuiKrete to cover your wall. You are limited only by your imagination.
Plastic Retaining Walls
You can also make a “man-made” type retaining wall using a flat piece of Styrofoam cut to fit the area where you want it and then glue on the surface an embossed plastic sheet that has the simulated appearance of brick or cut stone. You can buy these sheets from Walthers and other catalogs if you can’t find them in your local hobby shop. If you are creating a curved wall, I would fasten the Styrofoam in place first, let the glue dry and then place the plastic sheet on the surface of the flat Styrofoam “wall”. If you glue the plastic to the Styrofoam first before you try to curve it into place on the layout, it may not bend or curve the way you want it to.
Printed Paper or Cardstock Retaining Walls
This is basically the same idea as above, using the flat Styrofoam as the structure of the wall, but this time, instead of using a plastic sheet on the surface, you would use a printed sheet of paper or cardstock simulating the appearance of brick or cut stone. You can buy paper that is already printed like this or you can print your own using your computer and software that can help you do this. This type of wall would look better in the smaller scales than in the larger scales where it would be easier to tell that it’s just paper on the surface.
Make Your Own Mold
You could use an embossed plastic sheet or a retaining wall that you have purchased as the bottom and create a mold by gluing wooden sticks or styrene strips around the base forming an enclosure about ¼ inch deep and the height and width according to the size of the wall that you want to create. Paint or pour in your mold-forming latex or resin into the enclosure and let it dry completely. Once you pull off the mold and separate it from the base, you now have a casting mold that you can use to make a Hydrocal retaining wall. Just use the mold as the base, use the same enclosure you used before or make a new enclosure again about ¼ inch deep and pour Hydrocal into it. Spray the base of the mold with a mixture of water containing a drop or two of liquid soap before pouring in the Hydrocal to make it easier to pull the casting away from the mold after it’s dry. You can use the same mold over and over for as long of a wall as you want. When you place the wall castings on your layout side by side, you can hide the seams with painted strips of wood or use a small amount of Hydrocal in the seam and use a small trowel or dental tool to try to blend in the Hydrocal into the pattern of the brick or stone on either side of the seam.
Scratchbuild Your Retaining Wall
If you like to make things completely from scratch for your layout, this is for you. This is probably the best way to really get the wall that you want and make it fit into your layout like it was truly meant to be there. I found a fantastic example of how to do this at the following web page written by Randy Hawkins:
However you like to make retaining walls, and whichever method you choose, it will add an extra element to your layout, much like a bridge or a river, that will greatly enhance the interest and realism for you and your visitors.
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