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  • Mormon Rocks, A Three-Dimensional Backdrop Part 1

    Part 1

    by Ted York

    Photos by the author

    A Burlington Northern Santa Fe train is crossing the wash in front of Mormon Rocks at Pine Lodge. Ted is trying to duplicate this scene on his railroad modeled after Cajon Pass.
    Model Railroading - December 2005 - Page 28

    In the late 1840s a ragtag battalion of Mormon men, recruited by the United States government, marched into southern California to help defend the area during the war with Mexico. For a while they were assigned to defend the southern end of Cajon Pass several miles to the north of what was to become San Bernardino. Within a couple of years Mormons from Utah were entering California to settle the area. They made their way down the rocky desert canyon that would one day become the Atchison, Topeka & Santa Fe's gateway into the Los Angeles basin. It is said that they once camped below a large geological formation midway down the canyon that is known today as Mormon Rocks. The sandstone formation was created by upheavals of the San Andreas Fault, which lies beneath the canyon. Named after the Mormons who settled in the area, the very distinctive formation lies to the north of the tracks, in a location called Pine Lodge, where it is easily seen from both I15 and Highway 138 that run through Cajon.

    On my layout, Pine Lodge is located on a peninsula so there is no backdrop behind the bridge that crosses the wash in front of Mormon Rocks. All you see is the aisle and adjacent wall behind the bridge that crosses a wash. I really wanted to have a view of the Mormon Rocks formation because it is one of my favorite spots for shooting photos on the prototype. My first inclination was to just paint the scene on the adjacent wall, but after thinking about it awhile I decided that a three-dimensional scene might be a more interesting way to depict this sandstone formation. I had plenty of room across the aisle so I had the friends who were helping me with the benchwork install a shelf on the wall for the backdrop.

    Before getting into this project, I would like to take the time to say there are a "gazillion" ways to "skin a cat" in the world of model railroading. Some methods work better than others do, but many don't make a lot of difference in reaching the end goal, which in this case, is to create realistic scenery. Since the inception of my current layout I have developed methods that work for me. Some I've adapted from techniques suggested by a friend or from something I've read; some I've figured out for myself. Scenery is not "rocket science." Even though I espouse certain ways of doing things, I have been known to change on the fly. I equate the way I build my scenery akin to the way Justin Wilson, the Cajun Cook, would create a delectable meal. He would add a pinch of this, a handful of that, and a lot more of something else to the gumbo in the pot. He always seemed to love his food because he made it to taste. A satisfactory end result was more important than following a recipe to the strictest letter of the law. If I don't have the usual tools and materials at the moment, I make due with what I have on hand. If I run out of one type of plaster, I use another. If I can't find a piece of cardboard I grab some Styrofoam. I'll use whatever I find that will do the job. I would add that my intent is not to criticize any other way of doing things, only to offer up some ideas on how to complete the scenery on your model railroad.

    Ted fastened the beginning stages of his benchwork to the wall. The small crosspieces were screwed to the larger 1x4, which was screwed to the studs in the wall.
    Model Railroading - December 2005 - Page 29

    Since I have a fairly large layout, when I prepared to start scenery several years ago, I ran out and bought two large trash cans. One I filled with plaster of Paris and the other I filled with casting plaster. I filled an additional plastic container with Fixall, another plaster product. It had been a few years since Id done any plastering on the layout. So when I started the Mormon Rocks project I opened the plaster of Paris container to find hardly enough plaster to mix two batches. (I also found an empty soda can, a soiled rag, and several candy wrappers. It was obvious that my operators thought it was a real trash can.) Rather than go out and buy another bag of plaster of Paris I made do with some casting plaster. I point this out only to show how you can adjust and make do in the world of scenery. With that said, lets get started.

    The first thing I did was to change the level of the original shelf. My helpers (following my instructions, by the way) had installed the shelf at the same level as the portion of the layout across the aisle. The problem was that from the viewpoint I was trying to enhance, you could also see the fascia on the front of the Mormon Rock shelf. I decided to lower the shelf about 4" or 5" from its original position to make it look correct from across the peninsula. Keep in mind that the correct position is going to depend on your personal God-given altitude and that any one height will never be perfect for everyone. You might want to base your placement on planned camera angles if photographing the layout is important to you.

    My shelf is a simple grid of 1x4 pine capped with 1/2" plywood. I wasn't worried about having to make changes to this shelf after the scenery was in, so we screwed the cross braces to the rear 1x4 from the back of that 1x4. Next we screwed the assemble piece into the wall studs. Finally, another 1x4 was screwed to the front end of the crosspieces. My help cut a piece of 1/2" plywood to fit and screwed it to the top of the framework. If I built the shelf today I wouldn't bother with the plywood there is really no point in this application. A piece of 3/16" Masonite fascia was added to the front to give the project a finished look. When I started to photograph the shelf for this article I quickly A 3/16 Masonite fascia was added to the front for a finished look.

    When I started to photograph the shelf for this article I quickly realized I needed to add lighting before I went any further. I ran down to the local hardware store and found a 2' fluorescent fixture which would be perfect for lighting this small piece of real estate. After assembling the fixture I screwed it into the ceiling. I wired the light to the fixture that was lighting the railroad across the aisle. The light I tapped into happened to be the last one on its circuit, which made the job easy.

    To finish the carpentry I cut two sheets of 1/8" Masonite. One was cut to 24" wide to serve as the backdrop on the module while the other was cut to 17" wide for the valence. I screwed the backdrop into the wall on the right side of the scene then pushed the opposite end in until I got as tight a radius curve at the corner as I felt I could without breaking the Masonite. You might want to practice with a piece of scrap. Once the backdrop was positioned to my liking I screwed the other end to the wall. The valence was screwed into pieces of 2x2 that were fastened to the ceiling. Now I was finally ready to create the Mormon Rocks scene.

    I tell folks that one of the most important things they can do to make their scenery turn out well is to have photographs of the prototype in front of them. I just returned from a trip to California where I spent time shooting images at the Pass so I printed out a couple of the photos I had taken of Mormon Rocks and used them during the construction process. Even if you are not modeling a particular prototype, you are still modeling the prototype in general. Your scenery will turn out more realistic if you can acquire photographs of the type of scenery you have in mind. Im no artist. I cant take a block of marble and turn it into David. I use the reference photos and then spend time working on the scenery until it looks similar to what I want to portray. Trust me! If I can do it, you can do it too!

    This is the beginning stage of adding cardboard webbing to the module. Notice that he grabbed a piece of cardstock to form the base for a rock that is similar in shape. He tries to make due with whatever is handy at the time.
    Model Railroading - December 2005 - Page 30

    My preference for building scenery base is cardboard strips woven together and fastened with hot glue. This method can be a bit time consuming, but I think it is the easiest system for making adjustments. The desert canyon scenery that is Cajon is very recognizable due to the unusual rock formations such as Mormon Rocks. I find that when Im trying to reproduce such scenery, being able to make changes is important. Years ago, when I was planning the layout, I bought screen wire for the scenery because I was familiar with it, having used it on previous layouts. As with other ideas I had in mind during the planning stage, things changed when I was confronted with the realities of actual construction. Screen wire over forms would have been very difficult to change. And with all the changes I made as the scenery went up Im glad I went with the cardboard.

    I considered foam board, but changed my mind for a couple of reasons. First of all, the thought of having to cut the foam to fit the layout and then building risers to support the foam seemed too difficult and time consuming. Most of my benchwork (Mormon Rocks is an exception) is open L-girder. The track is laid on spline so there is no solid surface, such as plywood, to support the foam. I would have had to install risers and that seemed to be too time consuming and too much effort. The other thing I do not like about foam is that it acts like a sounding board, broadcasting motor and wheel noise throughout the train room. One advantage to the foam is that it is very light, but that was not really a factor for me on my home layout. Additionally, as I'll describe later, there is a technique using cardboard webbing which I have used on some modules that produces very light scenery, if that is important for you.

    Getting back to construction, I began to weave the cardboard strips into the shapes I desired for my scene. I recommend the single layer cardboard. It is easy to cut and easy to bend and weave. (Half of my layout it built out of the boxes that my fluorescent lights came in!) I use a hot glue gun to glue the strips to the benchwork and to each other. Wooden clothes pins are used to hold the cardboard strips together while the glue cools. Not having to wait for each joint to cool allows me to move a lot faster. At the plywood base and on the backdrop I simply put a bend in the cardboard and glued it to the wood. I occasionally step back to look at my work to see if Im headed in the right direction. This is where it is important to have those photos out so that you can do a comparison of your work to the real thing. If you need to make a change just cut and paste cardboard. It doesn't get any easier. Use the coolest setting on your glue gun. Do not use the extra hot guns. It is not necessary for this, and you will have fewer burns. But be careful anyway. I was gluing a piece of foam onto this project to build up an area that I had plastered. After the glue melted through the foam it ended up all over a finger I was using to hold the foam in place. The glue was still hot enough to produce a big blister and put me in pain for most of the rest of the day! (If you have to use hot glue to glue Styrofoam dont use very much glue.)

    The cheesecloth is covered with two coats of plaster of Paris. The plaster fills the holes and stiffens the structure in preparation for the finish plaster.
    Model Railroading - December 2005 - Page 31

    Once the webbing was to my liking, I covered it with a thin layer of cheesecloth. To save money I buy the material by the yard at the local fabric store. It comes folded like a tri-fold. Unfold it all the way so that it goes farther. You dont need it to be very thick. Again I used hot glue to fasten the cloth to the webbing. I dont use cheesecloth just to cover cardboard webbing.

    I used to have problems with plaster peeling up along the edges of the layout where I had used paper dipped in plaster to cross the gaps between plywood sub-roadbed and the fascia. It would sometimes peel up in other places too, but the edges were the worst because visitors and operators often hit them as they passed by. I started hot gluing cheesecloth to the plywood and the fascia. The cheesecloth acted as "rebar" for the plaster, and my peel-up problem disappeared. Now, I hot glue the cloth down anywhere I plan on using plaster for scenery.

    With the cheesecloth in place it was ready for a few coats of plaster of Paris. Mix the plaster to the consistency of thick latex paint. I use a cheap paintbrush to paint the plaster onto the cloth. You dont have to be neat. The object is to fill the holes and stiffen things up. Dont worry about sagging cheesecloth. Well take care of that later. The reason I use plaster of Paris for this step is that it sets up fast so the process goes quickly. Only mix what you can spread in a short amount of time. I generally use a cup of water for the mix (just add plaster to the water until you get to the right consistency.) I find it takes two thin coats over the cheesecloth to do the job.

    When I started the layout I bought a couple of cheap basketballs and cut them in half. The halves make perfect bowls for mixing plaster. After Im done with the bowl I just let the bowl sit until the residual plaster sets up. All I have to do is crinkle the rubber bowl and the plaster flakes off so you can dump it into the trash. Washing wet plaster into the sink is risky for obvious reasons. I do wash the brush out in the sink, but I dilute the plaster and let the water run for a long time.

    The right half of the scene has received the finish coat of plaster. He used a combination of the putty knife and a sponge to get the elongated crevices in the oval shaped rock at the lower right.
    Model Railroading - December 2005 - Page 32

    From start to finish, I continually compare what Ive done to the photographs. As you can see from the photographs Im not afraid to take a hammer to the plaster and fix things. If I rip a big hole in the mountain I simply add a bit more cheesecloth and plaster. It is that easy! In this project I used a couple of pieces of Styrofoam packing material to build up a few places for rock formations. Why did I use Styrofoam? Because the foam was the first thing I found when I decided I needed something. Later on in the construction I used a piece of cardboard to do the same thing. After being burned once by hot glue melting through the Styrofoam I found the solution was to use casting plaster like mortar to fasten the foam. But Ill get to that in a minute.

    I hand carve all my rocks. As previously stated, on Cajon Pass the rock formations are very recognizable. In essence, you have to scratchbuild them just like you have to scratchbuild recognizable buildings on a layout modeled after a particular prototype. I used to think that carving rocks into plaster meant hammering at hard chunks of plaster, chipping away in an effort to create something that looked like rock. Ive since learned that carving rocks is really a process of working with the plaster as it sets up; much easier and much more affective, especially for the sandstone scenery that Im duplicating. I use just a few simple tools: sponges, a palette knife, a wire brush, and an X-Acto knife with a chisel blade. I couldn't find the palette knife so I substituted a plastic putty knife for this project. The putty knife and a sponge were essentially all I needed to create the look I wanted for Mormon Rocks.

    I use a rather odd mix of plaster for my finish coat. A friend, Kelly Newton, taught it to me. It has worked well for me so I continue to use it. It is roughly a 50-50 mix of casting plaster and Fixall with a teaspoon or so of dirt. Im not very scientific about it. Most of the time the mix is probably a 60-40 or somewhere in between (remember Justin Wilson?). No matter, it always seems to work just fine. Despite the strange mix and otherwise unscientific methods I use, I can tell you that this mix sets up at about the perfect rate for carving, and it is plenty strong. I mix this finish plaster to about the consistency of cake batter. I use a spatula to scoop it out of the basketball and onto the layout. (My wife read this and told me to tell you not to take the spatula from the kitchen. Get your own! Fortunately for me I picked mine up at The Dollar Store!) As it sets up I use my tools to shape it into the rock formations Im modeling. With a little experience you'll soon gain a feeling for when the plaster is ready for carving. The process of carving rocks is better demonstrated than talked about, but Ill try to share a couple of methods I used for Mormon Rocks.

    The biggest secret to rock carving is the sponge. Sponges are great for adding the fine rock texture. They are really great for sandstone. Dragging a sponge across the surface will give you the look of weathered sandstone. Another trick I learned was to use a palette knife to make an elongated hole in the plaster. Wipe over the hole and you'll get the look of the interesting, sometimes odd looking holes you so often see in sandstone formations. I have used sponges to form the plaster into various shapes such as rounded rocks, eroded gullies, etc. Just experiment and remember to have those photographs out where you can see them.

    Now the entire rock formation is covered with the finish coat of plaster and ready to be covered with scenery materials. In the next installment Ted plans to bring Mormon Rocks to life as he completes his project.
    Model Railroading - December 2005 - Page 33

    In rockier areas you can chip at the setting plaster with knives and wire brushes. I cut one row of a wire brush off with a chop saw. (Do not forget to wear safety goggles. There will be bits of metal flying around when you make the cut.) The small brush is great for scratching at the surface. The carving of rocks is a whole additional discussion, but just experiment with ways to duplicate what you are looking at in the pictures. (Have I stressed that enough yet?) If it doesn't turn out, slap on some more plaster and try something different.

    I used my hand to smooth plaster in areas which are not rock and will be covered with dirt. I keep rubbing it with a circular motion until there are no marks in the plaster. It helps to keep your hand wet by occasionally dipping it in a bucket of water. I used to use my bare hand, but now I wear those thin latex gloves that the doctors and dentists use. The gloves keep my hands from drying out and cracking.

    Earlier I mentioned a way to do lightweight scenery using cardboard webbing. I used it on a couple of modules I built for the Utah Freemo modular group. Instead of using plaster over the cheesecloth I used brown paper towels. Lay the towels down and paint them with Elmers white glue diluted about 50/50. After gluing a couple of layers of paper towels over the cloth, I added scenic materials such as dirt and ground foams directly onto the towels just as you would onto plaster. Ill cover finished scenery in the next installment. I only wanted to mention the plaster-less method here to re-enforce my statement that there are lots of ways to skin a cat when doing scenery. What I found with the paper towel method I used on the modules was that I got extremely light scenery that flexed when it was moved. I think the flex has turned out to be a great feature for a module. I dont get the damage I see on modules that have plaster in their scenery. I didnt use the glued paper towels for scenery on Mormon Rocks because of the numerous rock formations I had to build. Cajon just lends itself to plaster; besides I still had a lot of it left over.

    Well, see you next time when I plan to show you some of my techniques for desert scenery. Meanwhile, cut up the cardboard that your easy chair arrived in and begin building some scenery for your trains to run through!

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