I need help creating a patch of desert for a school project. The diorama measures 7” wide, by 5” depth, 5” high (see pic) and is inside an acrylic display case, clear on all sides. I want to have a dune with some rock work embedded into the sand. My main concern is…
To create the dune, is it best to shape a base material into the dune, then glue a thin layer of sand to it or can large amounts of sand be mixed with glue to comprise the whole of the dune? The first option concerns me because people will be able to see the sides of the base material through the glass.
I tried reading Essential Model Rail Scenery Techniques by Sǿeborg but it didn’t really help. I just need someone to tell me what to buy and what to do
There are two ways to build a dune. One, take some cardboard strips about 1" thick and weave it like an upside down basket using a hot glue gun to hold the strips together where they cross one another. Use clothes pins to hold them together until the glue dries. Next, take some old newspaper and cut it into 1"-2" strips, then dip them in a slightly thin batch of plaster of paris and cover the cardboard “basket weave” frame with the plaster coated newspaper. Work fast because the plaster of paris sets up rather quickly. Then, get some cheap paint and paint the entire thing with a color like yellow ochre after the plaster dries. Finally, Spray the entire dune with water or 70% alcohol from a plant spray bottle and then use some dilute white elmer’s glue mixed 50% glue and 50% water with a couple of drops of dishwashing liquid soap in the mix and paint it over the dune. Then sprinkle in the sand over it all and when it dries, wahla! a sand dune. The paper strips are cheap to make. You can use plaster cloth in place of the newspaper strips but it’s expensive and i don’t think you want to spend too much money on it if it’s a school project.
The other technique uses the pink or blue styrofoam board that you have to cut into layers and stack on top of each other to the shape of the dune. Glue each layer between the sheets one on top of the other then follow the steps from the first technique from the painting with the yellow ochre on to the finish. The pink and blue foam can also be used to carve rock shapes with a kitchen knife by cutting and gouging the foam or by cutting the foam with a hot foam cutting tool. chuck
Definitely build up the shape of the dune with foam or something similar, optionally paint it a sandy color to avoid uncovered patches showing through, and then glue on the scenic material. Getting the proper shape of a big pile of sand and having it glued uniformly through will likely not work well.
[Learned this lesson the hard way in Junior High, not on a model railroad project]
One other thing I failed to mention from my previous post is that they have styrofoam blocks at stores like Hobby Lobby that florists use to mount artificial flowers in. (They are a dark green color) They also are easy to carve into rock formations with a kitchen knife and will work great for the space you are providing for your sand dunes. You can also paint them as described above except you want to use colors like raw sienna, raw umber, burnt umber, black and white.
To make a decent looking rock, carve it to your liking, Then paint it white. Once the white paint dries, take the black paint and get it real thin with water. (use acrylic or latex based paint) and brush it over the rock so that the paint will darken the nooks and crannies of the rock thru the capiulary action as the paint flows onto the rock. Next, use the sienna’s and umbers diluted 50% paint / 50% water and then paint over the rock. Finally, Take a very small artist’s brush and dap white highlights on the rock where the sunlight hits it. Don’t use too much white because highlights can be easily overdone…chuck
