Making Mountains

The Susquehanna river valley in upstate New York is very picturesque. It is hilly terrain containing farm land and forests. The area we are currently working is pretty much all hills. The only flat spots will be the wye and the gravel pits. This means we have to shape the scenery.

We are doing this by taking foam building insulation and stacking it up. Kind of like a wedding cake. Once we have the rough shape, we carve it down to the final shape. The tools we are using are the Woodland Scenics hot wire foam cutter, a wood rasp, Locktite's Power Grab glue and a vacuum cleaner. Don't even think of starting without the vacuum cleaner.

Building the hills is pretty simple. Get a piece of foam, cut it to a rough shape with the foam cutter. I generally just cut rectangles off of the narrow end, that are as wide as the cutter can make. The take this piece, position is where you want it and mark where you want to cut. The glue it down.

You can glue it to about anything, a flat plywood surface, the roadbed, the joists, or smaller pieces of foam that are glued to the joists, or the bottom of the road bed. The power grab glue is nice because you can cut a small piece of foam, put a bead of glue on top of it, then glue it to the bottom of the road bed with a few inches sticking out on each side. It will stay were you put it, and if you are careful you can glue additional pieces of foam on top of it.

Once you have the rough shape of the hills, you can used the hot foam cutter to cut of any protruding pieces. You cannot use the foam cutter to get the final shape. To do this I use the wood rasp to remove the last layer of unwanted foam. Then I use the vacuum cleaner to clean the benchwork, the floor, the rasp, my clothes, and the cat if he happened to be in the wrong place at the wrong time.

Next we build any rock faces that we want. We are using a variety of rock molds including some that were hand made by Jim and Ed. I have used plaster of paris in the past, but decided to try Hydrocal this time. The hydrocal seems to setup faster then the plaster of paris. All I can say about either product is make sure that it is fresh. Chuck gave me some old hydorcal and it took a long time to setup. The new hydrocal I bought setup 5 to 10 times faster. In fact I had one batch that setup so fast that it was unpliable by the time I walked from where I mixed it to where I applied it. You may be tempted to buy a 100 pound box of this stuff and use it over a long period of time. You are better off buying what you think you will use over the next month or two.

When mixing the hydrocal you want a thickness that is just thick enough so that it will slowly flow back a little after you stir it. If you suddenly stop stirring you should see a valley behind the stir stick. You then trowel it into the mold, drop the mold a couple of inches to get the hydrocal into the nooks and crannies and then press it against your hill side. You should overlap any previous castings. You will need to press the mold so that some of the hydrocal 'splurts' out from under the edges. Now hold it, don't move, don't release any pressure. Don't think about that itch that suddenly appears, don't think about the awkward position you are in. After a few minutes poke at some of the hydorcal that splurted out. If it seems firm, you can let go of the mold. You will want to carefully pry up the mold as soon as the hydrocal is hard, but still carvable (less than 10 minutes). Once the mold is off, you will need to carve the edges to remove any splurt and blend it into any existing rocks.

Once the rocks are in place we put a final layer of wood putty over all of the exposed foam. This smooths out the tool marks made by the wood rasp, and fills any gaps between pieces of foam, rocks and any tunnel portals you have. Larger gaps will have to be filled with old news paper or bits of foam before applying the putty. I use Durham's Water Putty. It is a powder that you mix with water just like plaster or hydorcal. Mix it to about the same consistency as you mixed the hydrocal. If you want to color it, you can mix in some artists acrylic paint (about 1" to a cup). I often use brown when making hills, or black when making roads. The paint will also slow down the drying process giving you more time to smooth it out. Once the putty is mixed, trowel it on to the foam. Then while it is drying use a 1" paint brush dipped in water to smooth out the tool marks. Once the putty is dry, you will have a nice solid surface to apply other scenic elements. If you still have some rough spots you can sand them down with a finishing or detail sander.