how did you build your mountians. i build mine with a foam base, then i build it up with foam and then i carved the foam. next i am in the plaster stage. finaly i paint/glue scenery.
Gidday Robert, I build my mountains using “Chicken” wire mesh as the base, it is sturdy enough to push and pull into different shapes without having to have to many supports. I then cover it with scraps of old cotton sheets dipped into “plaster of paris” to make a hard shell. Then I will plaster it and carve the plaster once it is hard if I want really rocky outcrops.
I also tried your method and it does work very well. Both ways can be messy though.
Keep having Fun, [:D]
Cheers,the Bear
Hi nscale rob
Stacked foam covered with plaster is what I use for hills and mountains how ever I mix PVA glue and primary school type paint in with the plaster.
The PVA helps with crack resistance the paint means no ugly white spots should it get chipped the paint also retards drying time.
Note paint should be darker than you think you need it will lighten as it dries.
Chook wire, paper balls or card lattice covered in news paper and plaster have also been used…
Once the plaster has dried the appropriate scatters and vegetation structures etc are then applied…
regards John
All I’ve got is hills, but the principle is the same. Generally, I build up a foam base, and then I apply plaster cloth where there are gaps, or I want to create a slightly different slope. Next, I apply painted and weathered hydrocal castings for rock faces and outcroppings of ledge. I mix Gypsolite, a gritty plaster, with water and some brown craft paint, and apply that as a general ground base. Once that dries, I paint the resulting tan base with a wash of green acrylic craft paint in a camouflage pattern. Finally, I add several varieties of turf and ground foam, loosely following the paint colors but allowing significant overlap.
My fist set of hills I used foam and plaster like you are doing, it turned up OK. Next set I still used foam, but I carved and painted and skipped the plaster. Turned out much better! I found some video’s on U-Tube and they where very helpful.
Cuda Ken
Gidday , I like the foam method because if you have a jewelry saw it is great carveing the foam.
Hello I am working on a mountian and so far I am useing foam. The plaster will come later. If you have some progress shots I would love to see them. Thanks Frank
the step before plaster
I use wadded up newspapers and masking tape for the general shape. That’s covered with paper towels brushed front and back with white glue. Once that’s hardened (perhaps with multiple coats) I cover the hills with brown sanded grout, which mixes up kind of like plaster but has a dirt-like texture to it so it’s not smooth like plaster. I use the “usual” grass and rock castings etc.
I use different methods for different areas. The one I use most is wadded up newspaper, placed in plastic grocery bags so the won’t get wet and collapse when I apply the plaster cloth.
This mountain was made with high density green styrofoam and covered with a wash of plaster.
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Hi nscale Rob, I happen to be in HO scale with a fairly large layout. The mountain shown in the photo is about 2 ft, high and is build over a reinforced plywood arc frame that is covered with old window wire screening (obtained free from the hardware store.) I prefer Hydrocal plaster to Plaster of Paris, since it is extremely hard and does not chip. The stiff wire window screening can be shaped to form gulleys and ridges that are extremely strong and hold trees vertical when glued to small holes drilled into the plaster. I vacumn away the plaster dust and then spray paint with various shades of brown and grey, and colors the holes that are drilled for a multitude of trees. Incidentally, if you plan on using hundreds of trees, Walthers catalog p372 offers a bushel of Scenic Express Super Trees for $115 that will make over 500 trees of HO size and 1000 n scale trees. Super trees make the most realistic trees imaginable. The mountain has a variety of functions. It hides the rest of the around the room layout from view from one location. A road winds up the mountain to skate&ski resort at the top. It is a hollow shell for four train tracks in a branched tunnel, and has a mine entrance with an ore loader on one side. removable portals allow access to derailed trains beneath. My only regret was that I did not frame the base of the mountain, so that the entire mountain could be lifted. Click onj photos to enlarge them. 
Nice, tomarrow i get to work on my N scale layout after i go Disc golfing.
Hey Nscale Rob,
I also use the wadded up newspaper and cardborad strip method, afterwhich I use plastercloth from woodland scenics, after the plastercloth dries, you can paint your terrain,
I model in HO, but the principles are pretty much the same.
I had a holding section that needed something. There was a fairly wide area on the backside, so I made a rock outcropping using pink insulating foam and some Woodland Scenics rock molds.
The area where the outcropping was going is the area to the left of the tracks. The fascia at the right side has been cut to follow the shape of the scenery.
I started by stacking and gluing sections of insulating foam. The blue color was from a project the wife was working on and will either be carved away or painted over. I used acrylic latex caulk to glue the foam to the layout and each layer.
After all the gluing is done. I let the caulk set for 24 hours before beginning the shaping.
After carving. I used a razor knife (the kind with the longer snap-off blades) and a wire brush to shape.
It’s messy work, but it’s easy to work with, and very lightweight. You DO have a shop-vac, right?
Any large gaps are covered with plaster cloth. Save yourself a lot of grief by covering any track and existing scenery to protec
Foam board was used to give my mountain size and a basic shape. Then I crumpled brown shopping bags to give them texture, un-crumpled them, and glued them to the foam board. I then coated the brown paper with small, irregular pieces of foam board and Sculpt-a-mold.
Interesting not many seem to use the cardboard strip method. I use 1 inch strips of corrugated cardboard woven in a web to form the terrain. I use hot glue to hold it together. I like this method because there is no mess and it is so easy to change by cutting and gluing. The web get covered with plaster cloth.
I’ve used the cardboard strip method, before I like it but I found that the insulating foam method is easier, albeit messier and more expensive.