DIY: Build a Modern Highway

The CSX W&A Subdivision crosses I-75 near Emerson, GA. Before modeling the actual overpass, I modeled the divided roadway that passes below. This stretch of I-75 consists of a divided highway, with three lanes of traffic in each direction. The results of this project can be seen in the photo above; the detailed step-by-step instructions are included below.

» Steps

Step 1 The highway is constructed using a common plastic FOR RENT sign that can be found at just about any hardware store or home improvement center. The following 18" x 24" sign was purchased from The Home Depot for less than $3.00, not bad considering a similar size sheet of styrene at the hobby shop would easily cost much more:



Step 2 Although the front of the sign has multi-colored printing on it, the back of the sign is plain white. This makes the sign an ideal material for modeling projects such as roads and highways:



Step 3 Each side of the highway has three lanes of traffic and an emergency lane on the right. I decided each lane would be 1" wide and the emergency lane would be 3/4" wide. With an additional 1/4" along the left side of the roadway, this resulted in a total width of 4" per each side of the highway. The depth of the highway underpass scene is 12", so I cut two 12" x 4" sections out of the plastic sign to use as the roadways. I painted the surface of the roadways using Testors Dark Aircraft Gray flat spray paint. This color was suggested by Dave Vollmer and is what he uses for his roads on his N-Scale Juniata Division layout. Here is one of the roadway sections after painting:



Step 4 The following photo shows the tools I used to add the traffic markings to the painted roadways:

• Woodland Scenics MG760 Dry Transfer Stripes (white)


• Woodland Scenics MG763 Dry Transfer Stripes (yellow)


• Ruler


• Hobby Knife with sharp blade


• Paintbrush with blunt handle (or burnishing tool)


• Reading glasses (this is the first time I have ever used this modeling tool)

Step 5 I begin applying the traffic markings by applying the solid yellow line along the left edge of the pavement. A solid line denotes oncoming traffic is to the left of this line, so be sure the side of the roadway with the yellow stripe is adjacent to the highway median. I applied the stripe 1/4" from the left side of the roadway. I used the 1/64" wide stripes on my roadways, which is a bit too narrow for the 4" wide stripes used on the prototype but looked best to the naked eye. Here is the first section of yellow stripe applied to the left side of one of the roadways:



Step 6 On the prototype, the dashed white lines separating the travel lanes are 10' long and spaced 30' apart. In N-scale, this scales down to 3/4" long stripes spaced 2.25" apart. The length of the stripes looked good, but the spacing was way to much when viewed with the naked eye. I settled on 3/4" long stripes spaced 1" apart. With my 12" long roadways, this allowed six stripes to be placed between each lane. This photo shows the results of applying the first row of lane stripes. As with the solid yellow stripe, I used the blunt back end of the paintbrush to burnish the stripes to the roadway. After applying the stripes to the roadway, I place the sheet of translucent backing paper (that comes in each pack of dry transfers) over the stripes and perform a final burnishing to make sure the stripes are affixed properly:



Step 7 Here is a finished section of roadway after applying all striping. The solid yellow line is placed 1/4" from the left edge of the road, the two sets of dashed white lane divider stripes are placed 1" and 2" to the right of the yellow stripe, and the solid white line is placed 3/4" from the right edge of the road:



Step 8 Before adding the roadways to the layout, they must be weathered. Unless it has recently been resurfaced, any busy road or highway will have dark oily streaks running down the middle of each lane that have been deposited by the thousands of vehicles that have travelled down the road. This detail is critical to the realism of a modern highway and is easy to reproduce using simple weathering techniques. Compare the two roadway sections in the following photo to see how the weathering adds to the realism of the modeled scene:



Step 9 There are several techniques that can be used to apply the weathering to the roadways, such as airbrushing or the use of commercial weathering powders. However, I prefer to use simple chalks to do my weathering. I purchase inexpensive chalk pastels from a local art supply store for about $1.00 each and use the edge of a hobby knife to scrape the side of the pastel to yeald chalk powder. For this project, I used two shades of Prismacolor NuPastel Color Sticks: Black (229-P) and Burnt Umber (223-P). I scrape off about twice as mutch brown as black and blend both powders together to yield a nice dark oily color that looks just like real road grime. A little powder goes a long way, so I just scrape a very small amount of powder off at a time:



Step 10 I use art sponges to apply the powder to the roadway.

• WARNING #1 As I mentioned above, only a tiny amount of powder is needed to waether the roadways. Always start by barely touching the sponge to the pile of powder and then applying it to the roadway by streaking it down the middle of each lane. You can always apply more powder to darken the weathering, but taking off powder that has been applied can be difficult. Which leads us to...


• WARNING #2 I have heard zillions of modelers describe how plain powdered pastels and chalks are poor choices for weathering because they come off so easily. However, while this may be true for others, it is not true for me. In fact, I have actually submerged weathered models into water and scrubbed them down, yet the pastel powder did not go away at all. This is probably because I always apply the powder after applying a flat coat of paint such as the Testors spray paint used for this project. Anyway, keep this in mind as you go and everything will be fine. In a pinch, I have found using a plain pencil eraser will remove any weathering that has gone awry and must be redone.

In this photo, two of the lanes have been weathered so far. The package of sponges contains about a dozen art sponges and costs about $2.00 at a local art supply store. I like to streak the weathering powder on with one side of a sponge, then use a swirling motion with the "clean" side to even out the weathering. I discard the sponge after each lane is done. The lighting in this photo makes the weathering appear much darker than it appears in person:



Step 11 The completed roadways have been temporarily placed on the layout with vehicles to see how they fit into the overall scene. They will eventually be glued to the foam layout base using caulk or construction adhesive:



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Layout Progress as of 3/21/2010

I have successfully completed the first ballasted section of track on the layout. After selecting the right ballast (see photos below), I ballasted the mainline, turnout and siding at South Emerson. This is the first step towards my goal of completing the scenery at the extreme south end of the layout.

» Photos

The following three photos show the ballasted trackwork that has been finished at South Emerson. You can see where the ballast ends just before the I-75 overpass:







This photo highlights two features of the trackwork: the superelevated mainline curves and the tall ballast profile. Both are hallmarks of a modern well-maintained, heavily-used Class 1 mainline:



I also painted the rails of the South Emerson turnout. The Micro Engineering code 55 flextrack I am using comes with weathered rails, but the Atlas code 55 turnouts do not. The shiny rails of the turnout have stuck out like a sore thumb for quite some time now; painting the sides of the rails and the tops of the guard rails worked like magic to blend the switch into the rest of the trackwork:



This photo shows the turnout at North Emerson before the rails have been painted. Compare the shiny rails to the painted rails in the previous photo. I use Polly Scale roof brown and a 000 (3/0) paintbrush to do this work:



I had planned on using Woodland Scenics fine ballast on all of the layout's trackwork. In my mind's eye, the Woodland Scenics light gray color would be an ideal match to the ballast on the CSX W&A Subdivision. Before I permanently ballasted the track, I thought it would be a good idea to do some sample sections by temporarily applying a bit of ballast (no glue) to a few sections of track.

Here is the Woodland Scenics light gray fine ballast on a section of mainline and siding. While I really liked this color, I thought it made the concrete ties of the mainline virtually disappear, even though it looked great on the siding:





The Woodland Scenics medium gray ballast solved the problem of the vanishing concrete ties, but I did not like the looks at all. Even though this color of ballast looks great on many other layouts I know of, on my layout it looked way too blue and certainly did not look anything like the ballast in my prototype photos:



Finally, I remembered at one time I had purchased some ballast from Arizona Rock & Mineral for one of my many previous layouts that never got off the drawing board. I found six bags of this ballast in two different shades of gray--along with a receipt from N-Scale Supply dated 2001! One of the shades, labelled #138-2 CSX/Southern Pacific/Wabash, was a perfect match and is what I settled on (as shown in the first set of photos at the top of this page):



I used about half a bag for the first section of track ballasting. My next task is to contact Arizona Rock & Mineral and try to order several more bags of their excellent ballast. I have heard the company is up for sale and may be closing any day now, so I have my fingers crossed that I can find more of this ballast or a suitable match.

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