Articles - Track: Handlaying Series: 2. Ballasting
03/03/2018

Making Ballast

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When hand-laying track, I prefer to ballast before laying the rail. This prevents the ballast from getting caught up in the rail, and it also allows me to manipulate the ballast to my heart's content without the rail getting in the way. I am currently using Arizona Rock & Mineral's HO-scale mainline size ballast for my S-scale layout. I also used that company's ballast when I was in N-scale. However, for S-scale I have also made my own ballast. I will describe how I did that here, although it is a bit time-consuming to make.
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Ballast, from my research, is rock about one to two inches in diameter. Ballast needs to be sharp for it to settle and grip well. Rounded river rock will not work. One day I was cleaning our parrot's cage when I realized the crushed walnut shells we use for litter for the bottom of the cage is just the right size. I grabbed the ruler, and, sure enough, it was, on average, two scale inches in diameter (for S-scale, that is). It has sharp edges. It is called Kaytee Walnut Bird Litter. It is about $11 for a bag at Petsmart and you will find it in the bird or ferret aisle. The advantages of using crushed walnut shells are that it is relatively cheap (one $11 bag will probably provide enough material for an entire large layout), it is light-weight (great for modules), can be colored to match your prototype's ballast, and is readily available (most larger towns have a Petsmart or similar pet store). The disadvantages are that it takes more time to prepare, and doesn't look like rock until it has been prepared and weathered. The advantages of using real rock are that it looks like the real thing because it is, it doesn't have to be colored, the rock dust will "weather" the surrounding ties, is ready to be used right out of the bag, and is available in different sizes. The disadvantages are that it is harder to obtain, can be heavy in large quantities, is relatively expensive, and color selection is limited.
Handlaying Series: 2. Ballasting
The crushed walnut shells look like, well, walnut shells. This is not the right color for Pennsylvania Railroad ballast. That is more a mixture of white granite and dark-gray coal. I color the crushed walnut shells using Delta Ceramcoat "Hippo Grey", white, and "Charcoal" (not shown). These acrylic paints can be found at any arts supply store for about $1.50 each. Any kind of acrylic paint will do (oil-based paints don't seem to work on walnut shells), and any color of gray will provide the balance between it and white. You can experiment will small batches and different ratios. You can, of course, use any number of colors.
Handlaying Series: 2. Ballasting
I grab a handful of crushed shells and put them in a bowl. Next, I add a good amount of paint and a very little amount of water; just enough to make it mix easily. If you add too much water, the color is thinned too much and the color won't take. However, if you don't use enough water, the walnut shell pieces become glued together and can be difficult to separate. Experiment to find the right consistency. Make each batch of a separate color (mxing will be done later). I thoroughly mix the paint until I no longer see any tan-colored walnut shells.
Handlaying Series: 2. Ballasting
Next, I spread the mixture out on a piece of glass and let it dry overnight. I do the same with the other color or colors. I used to use newspaper for drying, but the ballast was hard to remove from the paper. Sometimes the paper would tear off and stick to the ballast, which would be visible on the layout. Not good. The paint will actually make the ballast stick to the glass as well, but it can be easily scraped off and the glass can be washed with hot water and soap.
Handlaying Series: 2. Ballasting
Once the ballast has dried (usually overnight), I try to remove it from the glass. I break up the ballast while working it on the glass surface. If there are parts that are really globbed together, I throw those away. What I am looking for is individual pieces of walnut shell, only colored. I then place all the ballast in a plastic jar (one that has a lid), insert some metal weights, and shake and rotate the jar for as long as I can. This really breaks them up, mixes the colors nicely, and even rubs some of the darker ballast onto the light ballast. It gives the whole thing less sharp of a contrast between the various colors. When it is all done, this is what I get.
Handlaying Series: 2. Ballasting

Applying Ballast

If the track has a slope, I glue the ballast to the slope area first. This will provide a barrier for the remainder of ballast; keeps it from falling down as I adjust it. To get the ballast to stick to this slope, I use full-strength matte medium (white glue would work as well). I cover a section with the matte medium using an appropriately-sized hand painting brush. I then sprinkle the ballast over the area using a teaspoon. I put a sheet of paper under the area so that I catch most of the ballast that falls off, so that I can use it again. I also gently blow on the area to remove any ballast that didn't get glued down. The matte medium takes about an hour to dry.
Handlaying Series: 2. Ballasting
Next, I use the teaspoon to put a pile of ballast in the center of the ties and carefully work it into the ties. I use my fingers for that. I also use my finger to tamp it down so that it will stay and that it is even with the tops of the ties.
Handlaying Series: 2. Ballasting
When I am happy with the ballast, I use a fine-mist sprayer filled with water and a few drops of dishwashing detergent (this mixture is typically referred to as "wet water") and soak the area that I am about to glue. You can also use rubbing alcohol, but that really leaves a strong smell, especially in a closed off room. Water works just as well, but without the smell. Although water can do damage to surrounding scenery or structures, if you already have those in place. Use rubbing alcohol in that situation, because it evaporates faster. At first I spray very lightly so as to not to disturb the ballast, and then I soak it more heavily. The purpose of the water is just to allow the glue to be more readily absorbed into the ballast. I use a small, re-used Elmers white glue bottle for applying the glue. It allows me to place one drop in just the right spot. The glue is actually a mixture of 50% matte medium, 50% water, and a few drops of dishwashing detergent. I usually mix a large bottle of this material (because I also use it when I make scenery), and then just pour it into this small bottle. The ballast is covered with this glue mixture one drop at a time. I try to avoid placing the glue on the ties, because it can leave a watermark on the ties (this is not so much of a problem if you use alcohol). I let this dry overnight.
Handlaying Series: 2. Ballasting

Store-bought Ballast

Although the approach I described above works well, it is rather time-consuming and messy to make my own ballast. I now use Arizona Rock & Minerals' "HO Mainline" ballast. This is larger ballast, and actually flagged to be used for O-scale by the company. I bought some and found that the average ballast pieces come out to just under two scale inches in S-scale. This is just about right. It is definitely easier to buy these bags rather than to make your own. The company's new owner has made it very easy to order online, so it is easy to buy even if you don't have a local store.
Handlaying Series: 2. Ballasting

Non-ballast Ballast

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Sometimes thinking outside the box is good. Years ago I was at the arts and crafts store Michaels and found containers of coarse sand. These are typically used for making clear-glass fake (or real) flower containers, where layers of colored sand are used in the container for decorative touches. These are available in a several colors, two of which I show here, namely gray and black. Size-wise they have granules that measure between 1 and 3 inches in S-scale. Perfect for yards, coal industries, or hopper car loads. One of these containers costs about $4.
Handlaying Series: 2. Ballasting
Here is a photo showing the two different colors. They are classified as a "sand" and water is not recommended. I have had no problems using these as ballast and using regular ballasting techniques (wetting it down before spraying a mixture of 50/50 white glue and water). You could use rubbing alcohol instead of water, especially the 90% variety, if you are concerned about water breaking down the sand.
Handlaying Series: 2. Ballasting