How to Build a Model Railroad Mountain With Foam Board

Mountains enhance the scenery of your model railroad. You can make your own mountains out of a wide variety of materials, but foam board offers flexibility and low cost. Foam board mountains are made by layering sheets of foam board, covering them with plastic cloth, and adding your own paint finishes.

Determine the size and shape of your mountains, according to where you will place them. Draw the approximate size and shape for the base of your mountain onto a piece of paper. This will serve as the tracing template for the base of your mountain.

Trace the shape of the template onto a foam board sheet. Cut out the base shape of your first piece of foam. Use the base piece as a template to draw the shape on another sheet of foam. Cut the second sheet of foam so it’s about an inch smaller than the first one.

Trace your newest layer onto another sheet of foam. Cut the next layer about one inch smaller than the previous layer. Continue this process until your mountain comes to a point. Repeat these steps until you have completed the basic shapes for all of the mountains you wish to make.

Cut off the edges of the foam, and then move the layers around slightly to make your mountain look more natural. Reshape your mountains until you’ve achieved the texture and look you want from them.

Glue your foam board pieces together by applying epoxy in between each layer.

Trim the upper edges of the foam board sheets with a hot knife or foam cutter. Your hot knife will also allow you to enhance the shape of your model train mountains by making crevices or indentations.

Cut and glue any extra shapes you’d like to add to your mountains. Add foam rocks and rock formations to make each mountain more individual.

Cut several 6 to 8 inch lengths of plaster cloth. Place one strip of plaster cloth in a flat pan of water for a few seconds, just long enough to soak the length with water. Place the sheet of soaked plaster cloth on the foam form, starting at the top. Cover over a section of the mountain with the cloth. Continue this process until the foam board underneath is no longer visible. The plaster cloth will conform to the shape of your mountain and give it the proper texture for painting.

Paint your mountain with latex paints in order to give a thick coat of even color. Applying beige and flat black to different faces of your mountains will help contrast the faces of your mountain. Consider dusting on some dry pigments to add the effect of mineral deposits. Green shades of pigments can also be dusted on to add fields of grass to the sides of your mountain. Once your mountains are entirely covered with these scenic painting techniques, you can allow them to dry and add them to your railroad scenery!