Scenic Diversity
Topic: Scenery

It seems as though my days in college geology class were in a land far away and a time long ago, but if I recall correctly "discontinuity" is  the name for what is pictured in these photos taken during my recent trip to Colorado. Technically, a discontinuity is the surface at which seismic waves passing through rock change speed. Visually, it is a line along which two differing types of rock meet. This geological phenomena can be useful for model railroads.

 

 

 

 

 

 

 

 

 

 

The rock formations on any model railroad layout usually exhibits a good deal of uniformity. The same rock texture and color tends to persist from scene to scene. More variety can make the scenery more interesting and make the layout seem larger. On the MKP layout I took full advantage of radical changes in rock strata. Rock formations in the East and Midwest make fewer and usually less obvious changes than those of the Rocky Mountain West.

At first this can look like you are creating a calico cat. It takes a bit of courage to make these abrupt transitions. But as you add ground cover, trees, and other vegetation these additions compete with the rocks for the viewer's attention and soften the contrasts between rock types and colors. The variety adds interest and a sense of place within the overall scenery. So that which at first seemed un-natural becomes completely natural.

 

 

COLORING THAT MOUNTAIN
Topic: Scenery

Guess what? The lost is found. This entry disappeared not into a black hole, but perhaps a Lycos wormhole and it ended up in an earlier time. Even though the editing date clearly appeared as the year 2007, it was posted to the year 2002. Now that was before I even started this journal. For other purposes I happened to be looking back through all of my posts and low there it was, back before the begining.

Awhile back I described the steps I used to add color to rock castings along a a small cut in the Missouri portion of the layout. I use the same methods for coloring the Colorado mountain areas but it may be easier to see with these larger surfaces. Coloring rocks is one of the most fun parts about scenery, but perhaps also one of the most challenging. It takes a bit of an eye for color, however, if you spend some time looking at real rocks and do a bit of analysis of the color you can begin developing that eye for color. One thing you will notice is, aside from gemstones, the color of most rocks is on the drab side. The colors are relatively subtle and often have a lot of white in them. The coloration is seldom uniform. The color of a rock is often the result of particles of several colors which produce an overall impression of a single color. We are never going to perfectly reproduce all of the subtle variations of color in a rock, but we can use techniques to produce a depth and complexity to the color of our castings which heighten the impression that we are looking at real rocks.

I always have a minimum of four steps in coloring any rock formation. I begin with black. My black is dry powder tempera paint which you can find in stores marketing teachers' supplies. I will then apply at least two colors of acrylic paint. I use the paint available in tubes from any art or craft supply store. I purchase the most inexpensive paint available. You're not going to be painting a personal version of the Mona Lisa and the cheap paint will do just fine. I don't use the liquid acrylic paints so popular at Walmart as I don't feel I have as much control with them as with the tube paints. When I say I use "two colors" I may not be using two entirely different colors, but merely two different tints of the same color. The final step, no matter how many intermediary colors have been applied, is to bleach the colors with an overall very thin application of white.

I apply the black tempera paint dry with a two inch brush. I apply it much as might an old woman powdering her face trying to cover up those age spots, i.e., heavy. This is a dry, dusty process and black powder floats everywhere. I recommend using a face mask to avoid inhaling this stuff. Be really vigorous with your brush working the powder into every nook, cranny, and surface. Don't forget the underside of your rocks! When finished, you're going to have a fair amount of powder which didn't adhere to your castings and has settled on any flat surface below your rocks. Vacume up this left over powder; it is waste. Failing to vacuum the left over powder is going to mean big puddles of black paint after the next step in the process.

The next step is to rinse the entire area with water from a spray bottle. The more water you spray on the rocks, the less black color will remain. If you want dark, moody mountains use only a little spray. If your mountain is to have a lighter color, spray with more water. The spray turns the powder to a black liquid which can settle into the cracks and details of your rock casting. The black will also adhere more to those surfaces which are rough. This procedure introduces the first variations in coloration and will influence each succeeding color application. I call this step "shading". It is roughly equivalent to the "shadowing" which others do with a black ink wash as their final step in coloring. I believe applying the black at the beginning of the process will result in modifying the shade of colors applied later without covering up those colors.

In technical terms, a "shade" is the color which results when a colored pigment is added to black. The relative proportions of black and colored pigments determines if the shade is darker or lighter. Likewise, a "tint" is the result of the colored pigment being added to white. So the following steps in the process are adding tints to the color of the castings. It is more usual to create "tints" rather than "shades" due to the presence of white in so many rocks and to the fact that the illumination of our layouts is many times less intense than that of sunlight illuminating real life scenery. For this mountain I chose to apply tints of burnt umber, yellow ocher, raw umber. burnt sienna, and raw sienna. The following photos show the results after application of each tint in succession.

 

The addition of each color may produce a subtle or a dramatic change, but each is adding to the depth and complexity of the overall color. The final color I add is a thinned white applied with a dry brush technique. I squeeze some of the the white acrylic onto my palette. With my brush quite wet I draw a bit of this paint out. Then I stroke the brush on a dry piece of paper to remove some of the paint. This creates what is called a "dry brush" with which I then start brushing the rock castings in a downward motion. It is important to use only downward strokes because you want to avoid leaving white paint on the undersides of the rocks. This simulates the effect of sunlight which comes from above. I start with light strokes followed by more vigorous ones to stretch the paint out on the surface as a thin film. It requires some practice before you will get the right results. The goal is to leave only enough white paint to create  a very light haze on the rock castings without significantly changing the underlying color of the rocks. This haze gives the rocks a dry, dusty, and sun-bleached appearance. The haze reflects the incandescent lights I use for layout lighting and creates highlights on the rocks and enhances the shadows when you view the rocks at an angle from the light source. So that's how I colored that mountain.

 

 

The Rock Pile
Topic: Scenery

One of my goals for my Colorado trip was to make new rock molds. The weather wasn't entirely co-operative. As a consequence, I was not able to fully complete the molds before it was time to leave Colorado. By working carefully I was able to remove the molds from the rocks, but the molds were too thin for use. After my return to Missouri I picked up a bag of perlite. I spread the perlite in a cardboard tray. I pressed the incomplete molds one at a time into the bed of perlite. With the perlite acting as a support, I tried to shape the molds as nearly as I could into the contours they had on the rocks in Colorado. I then proceded  to fill each mold with Hydrocal.

When it hardened, I turned the molds over and added a heavy final coat of latex. As is my normal practice, I incorporated cheesecloth into this final coat. After the latex cured I peeled the mold off the Hydrocal cast. Presto, I had my molds! All of the fine detail was there and the contours were very rugged.

 

With the new molds in hand, I set about adding rock castings to the hardshell mountain which had been sitting naked for a whole year. This is the mountain inspired by the Highline section of the Durango & Silverton Narrow Gauge Railroad. The track will creep along a ledge nearly 200 scale feet high. After two weeks of work and maybe 70 pounds of Hyrdrocal the casting is nearly complete.

This route would have been built in the later part of the 19th century with dynamite and hand labor. So the N-scale size workers would have removed no more rock than required and clearances would be at a minimum. Not unlike these little workers, I've had to chip away at the castings to allow enough space for the trains to pass. As soon as the last cast is complete, I will put a passenger car on the track and see if I've got the job done right.

I have intended to call this the "Highline", but with the rugged rock faces these new molds have created I think I may need to rename it "Hanging Rocks" because of all the rock overhangs which loom above the tracks. The next challenge will be to come up with appropriate coloration for these cliffs.

We've also been working with rocks of another sort, real rocks this time but little ones. Thanks to Jerry Prott and his friend I have been able to come up with a local source of ballast for the garden railroad. It is called "trap grit" and is available in bulk at a very economical price from Breckenridge Materials. It is mostly black rather than the cherry color of the chicken grit I'd been looking for. This trap grit may not be as pretty, but after all of the hassle trying to come up with any ballast this stuff looks beautiful to me. Doug and I were able to re-ballast about half of the  track in just half a day. It was the easy half since it didn't include any of the trestles or major washouts, but we should be able to finish up next week. Most of the railjoiners will have to be replaced, however, due to corrosion.

Highlights & Shadows Revisited - Again
Topic: Scenery
I hope I don't seem to be harping on this subject, but I feel highlights and shadows play a critical role in creating a natural appearance for your rock castings. Use of appropriate color may be of greater importance. However, highlights and shadows are crucial factors for convincing rocky scenery.

Last night I took a closer look at the rock formations in some of my layout photos. In the close-up view I think you can see the effects of the techniques I have used to create believable rock formations. We can't approach the intensity of a sunny day on our indoor layouts, but we can attempt to emulate the directional character of sunlight. That is why I choose to use halogen lighting rather than fluorescent. I also try to direct the lamps in such a way that illumination comes from the side of the most typical viewing location. These actions mean that layout lighting is itself creating highlighs and shadows. Whereas the intensity of our halogen lamps is incapable of shining with the brightness of sunny highlights or casting the depth of natural shadows, we must give the artificial lights some support with our painting techniques.

You will notice highlighted portions of the rocks are not white. They are a paler tint of the stone colors. This is the result of my use of very thin white paint when I dry brush the rocks. The thin white paint doesn't hide the rock color. It combines with the color as a lighter tint the original. And this is why I call my technique bleaching rather than highlighting. My technique is designed to enhance, not substitute for the highlighting action of the layout lighting.

Likewise you can see the shadows are not black but merely a darker shade of the rock colors. By applying the black color as the first step in painting the plaster castings it darkens the succeeding color applications. It does not cover up those colors as the black will if it is applied last. Good rocky scenery must start with plaster rock casts possessing as much detail as possible, but it is our treatment of lighting and color which will cause the viewers to think they are looking at real rocks.

Building Me A Mountain
Topic: Scenery
Model railroaders are sometimes needlessly intimidated by the prospect of adding scenery to their layout. You shouldn't be because it is probably the most forgiving aspect of the hobby. Some of your best accomplishments might happen almost by accident. There is endless variation in nature. Therefore in most circumstances you don't have to be concerned with duplicating particular details. Scenery gives you the opportunity for personal expression and creativity. Even when modeling a particular prototype location your goal is to capture the character of the scene. Model railroads never have as much space as the real world railroads. As a consequence, you never will be able to replicate the scene in every detail. Your success will be making the scene immediately recognizable to someone familiar with the location.

When doing scenery there is no right or wrong way to do something. All that counts is the result. Scenery is also where you can develop your own personal style. This style is a consequence of how each individual perceives the same scene and of the techiniques by which the modeler chooses to express that perception. I use a variety of techniques in the creation of my scenery. My choice is dependent upon which I feel is best suited for the scene I'm attempting to create.

In this photo you can see three methods which I use in the creation of land forms. My method for building low lying hills is located closest to the camera and at the right corner of the photo. Tightly wadded newspaper is piled up and then held in place with masking tape. Plaster gauze bandages dipped in water are used to cover the piled up newspapers. A second method can be seen just above the newspaper method and to the right of the center of the photo.
With a hot glue gun, I have glued together scraps of pink foam insulation left from other projects on the layout. I then trim (with a hot wire tool) the foam pieces into the shape I want. Just as with the newspapers, I cover this with the plaster gauze material. Some people carve the foam itself into rock formations, but I have never been very successful with that technique and prefer instead to create all rocky surfaces with plaster castings. The castings don't adhere well to the bare foam so I must cover it with the plaster hardshell. I chose to use foam in this instance because I had a narrow space in which to create a steep canyon wall. I could have taped wadded newspapers to a profile board cut from a thin sheet of pink foam. Using all foam, however, seemed to me to allow more control over the finished form and permitted more rugged shapes.

I build big mountains, some more than four feet high. Stacking layer upon layer of extruded foam insulation or wadding up piles of newspaper have limited usefulness for the kind of mountain scenery which I prefer. Instead, I use wire netting ("chicken wire") as an armature over which to build my mountains. This mountain building technique has been around a long time. Some might even consider it out of date. But I give it a little different twist by using the wire in combination with polystyrene rigid foam insulation.

Most of our efforts this past year have been devoted to the urban area of the MK&P's layout. It wasn't until later this summer I began turning some of my attention back to the mountains. The highest peak on the 30 foot long mountain ridge I call collectively Strontia Springs seemed to be suspended in air since before Christmas 2004. This is not a good condition for a mountain. It needed some greater connection with the ground. The peak is located in a corner of the layout. Bringing the mountain back to earth meant turning the corner to move down the next wall. Turning a corner, even an inside corner, is no big problem with a track plan. You just put in a curve in the tracks. I was to find it is not always that simple with a mountain.

This represents my third attempt to arrive at a satisfactory form for making the 90 degree turn. My first idea here was to create a steep canyon with a dramatic waterfalls. But I had been forced by space constraints elsewhere to locate most of mining town into this area and there was not room in which to fit both town and waterfalls. My next attempt was a high peak and it also was too steep to be compatible with the townsite. What I finally settled on is still very steep but with further modifications made after to initial hardshell (which I will show) I have arrived at a form satisfactory to me.


A wire cutter and a Woodland Scenics low-temperature glue gun are my primary tools. I also use a razor knife for cutting foam. A word of caution when working with the chicken wire, the ends of the cut wire are very sharp. I recommend wearing safety glasses when manipulating the wire. The wire pieces tend to flop around and my glasses have saved me on more than one occassion. You might also want to wear gloves to protect your hands, but I find that too cumbersome. I have shed more than a little blood for my scenery! This is probably the reason why many prefer not to work with wire netting.



The chicken wire netting comes in large rolls and must be cut into sizes which are manageable and to fit the area where you are building your mountain. When first cut from the roll, the wire retains the curved form of the roll. I crumple the wire section into a loose wad and then stretch it back into a more or less flat piece. This begins to give the it the irregularities of a mountainside. I then further manipulate the section into whatever form I am attempting to give the mountain.

The chicken wire netting is not the easiest material to work with, it can have a mind of its' own. But I look on that as among the advantages of this material. It can take unexpected shapes as I manipulate it. This gives the mountain what to my eyes is something of a random, and therefore, natural form. It also keeps its' shape while still allowing easliy made changes.

As I shape the wire netting to form the mountains, it is necessary to find a way to anchor the netting to the foamboard which is the comprises the base of the layout. With its' fast setting time hot glue fills the bill. I tack down the edges of the wire at many points with the hot glue. Be prepared to use a lot of the glue to make all of the connections. The hot glue doesn't make a strong bond with the foam so you need numerous points of connection.

The wire netting will hold the shape you give it. Until, that is, you cover it with heavy, wet plaster gauze bandages. The wire must be given some additional support to prevent sagging until the plaster hardshell has dried. To give that support, I make struts from scraps of pink foam. The struts are held in place with more hot glue. After the hardshell dries you can remove these struts if needed for access under the mountain. All of these struts and foam may not look very attractive, but it is all going to be covered up. What is important is that it does the job.

Attention must be given to providing access to any track under the mountain. Whereas the open grid benchwork has been covered with a two inch thick sheet of pink foam, at this point you need to have removed portions of the foam. This is done with either a keyhole or drywall saw. You can see in this photo where foam has been removed between the cross supports of the benchwork. You can also see how foam was used to support the Woodland Scenics foam incline, risers, and track.

With the wire netting and foam in place, the mountains are ready for hardshell. I use plaster gauze bandages to do this. This material is available from Woodland Scenics at local hobby shops. Because I am using a lot of it and need to save money, I procure mine from PEL Medical Supply in Ohio. You can also use the time-honored method of dipping paper towels in Hydrocal plaster, a more time consuming and messy method. Wait at least a day or two for the hardhshell to dry out before proceeding further.

I am not done with hardshell, however. You now have a much clearer view of your mountain with the hardshell in place. No doubt you have failed to see the complete shape of the mountain with only the wire netting in place. Now you will be able to recognize some things which need changing. There will also be some formations and details which you want to add and which aren't easily given shape with just the wire netting. More foam and hot glue to the rescue! Scraps of foam can be attached with hot glue to the hardshell in areas which need correction and additions.

Not all of the foam additions must be done with pink foam. This is one place where you can use the white beaded foam such as comes as packing materials around computers, TV sets, appliances, etc. This foam lacks the structural strength of the pink foam. Also, unlike pink foam the white beaded foam is highly flamable. Neither of these failings is important here, as the foam will be completely encased with plaster hardshell. After attaching the foam scraps they can be further shaped with a hot wire or hot knife tool. More hardshell is then applied over these foam additions.

I wasn't done yet with the hardshell modifications. The base still seemed to too small for the mountain above it. We made a wedge-shaped addition to fill in the corner and allow a small extension to the mountain. More foam scraps filled out the front of the mountain putting it on a better footing.

You can see from the photo that I have already applied rock castings to much of the mountain. These rocks were cast with the molds made in Colorado. I described in an earlier entry how those molds were made. I make the rock castings by filling the molds with Hyrdocal plaster. I use Hydrocal because it picks up the detail of the molds better than other plaster types. It is also faster drying which is both a curse and a blessing. Your window of time to work with the plaster is limited, but this also means you can make castings more quickly.

To mix you your plaster, add plaster to water. Don't pour water into the plaster powder you are going to mix. I am always asked about the recipie for mixing water and plaster. Frankly, I don't have one. There are too many variables to give an exact proportion of plaster and water. What is needed changes with mixing time and conditions. Very roughly speaking you are going to end up twice as much plaster mix as the amount of water you start with. For me it seems to work best to slowly add the plaster powder to the water and wait for it to aborb the water. I then gently stir the plaster until it is thoroughly mixed. I next add some more powder and repeat this process until I have arrived at mixture with the thickness I desire. There are a variety of descriptions of the desired thickness. I guess I'd say it was like cake batter.

After I have filled the molds with plaster I wait until it has set sufficently that when the mold is moved and flexed small shallow cracks open and then close in the plaster. If the little cracks don't fill in immediately you have waited too long. As soon as the plaster has set to this extent, I apply the mold to the hardshell surface of the mountain. While waiting for the plaster mix to start setting in the mold, I have prepared the hardshell by misting it with water. This encourages the casting to grab hold of the hardshell when it is applied.

The plaster-filled molds are flexible enough to conform to the shape of the hardshell. This means you can apply the same mold again and again without creating a repetitious appearance. The underlying shape changes and this causes the surface appearance of the rock castings to change. All of the rock casts on this mountain were made with just four molds. Leave the mold in place until the mold begins to warm slightly. This warming happens because of a chemical reaction which occurs as the plaster hardens. The mold may become very warm to the touch if it remains in place. It is best to carefully remove the mold before this, however, as it becomes more difficult to remove the mold after the plaster hardens. This will increase the wear and tear on the mold and it also means the plaster will be too hard for even minor modifications to be made to it.

To avoid your cliff having the look of mosaic tiles, you must overlap the edges of the castings. If you have removed the mold from the new casting before the cast has become too hard, you will be able to chip away at the new casting with a putty knife, screwdriver, or other small tool to blend the new casting with the previous one. If you remove the mold too soon bits of the plaster will remain in the mold and you will lose details in the rock cast.

Because of the waiting time between when you have filled the mold with plaster and when you can apply the mold to the mountain, there is a temptation to continue filling additional molds. I advise against doing more than a couple molds at a time. The interval during which the molds are best applied to the hardshell and the time which you have to blend the new cast with the prior one is very brief. It is likely you won't have time to work with more than two molds. You may, in fact, find it difficult to accomplish with more than one during this limited time. I also find I may get confused about the placement and orientation of each mold. This may not always be crucial but sometimes it means you will feel you need to remove an improperly placed casting. This can require you to replace the hardshell as well because the rock casting has become too firmly attached by be removed separately. (I assume you don't have to be told how I know this!)

After finishing all of the rock casting, I prefer to wait at least two or three days before you begin coloring the rocks. I'm not sure there is any good reason for this since fresco painting is done on wet plaster. In an earlier post I have described my technique for coloring rocks. You can find that by clicking on the "Scenery" button in the topics list. I wanted a "volcanic" character for this mountain and used grays in addition to umbers and ochre for coloration. Of course I followed my usual practice of beginning with black tempra powder and finishing with titanium white to bleach the rocks. So that's how I got my newest mountain. The Nighthawk townsite awaits more buildings before it too can be completed.