Model Train Bridge Scene
A river crossing can provide a dramatic backdrop to a model train set. The change in elevation helps eliminate that “tabletop” look of the model layout while making the entire platform more natural and realistic. It's not difficult to create, either. This bridge and river scene can easily be completed in three or four evenings and that accounting for both the time needed to plaster and for the paints to dry.
Your river scene doesn’t have to be intricate to be interesting. By using recycled components, you can make it an affordable pastime to share with your children. A few tips and techniques will put you on your way to a realistic looking train scene that will make anyone envious.
Planning the Bridge Scene
Building a successful train scape requires adopting the mind of an engineer. First, study the prototype pictures on the train's box—as well as any additional images you find online. Then take these things into account during your planning process:
- Take note of riverbanks and specific bridge types and supports in the examples you find.
- Think vertically and plan to add scenery above the tracks as well as below it.
- Line out appropriate areas to place your bridge, while reserving other areas of the scene for topography like rolling hills and railroad cuts.
- Make your bridge look real—as if it's planted into the earth—by planning for proper abutments and foundations.
- Plan out your color scheme and source good paint for the longevity of both the train and its backdrop.
Choosing the Right Bridge
Constructing a realistic bridge scene begins with placing your bridge and then designing all the other elements around it. Unlike real engineers, hobbyists can make the “natural environment” fit the bridge, and not vice versa. So go back to your prototype photos and choose a style of bridge that suits you.
There are dozens of different bridge models available in almost every scale. With a little creativity, train kits can be kitbashed (modified or combined) to create even more options. If you're committed to building an exact replica of a specific bridge, you may need to start from scratch.
The subject of this article is a small steel bridge spanning Raccoon Creek, a small tributary of the Ohio River near Monaca, Pennsylvania. Just upstream, the former Pittsburg and Lake Erie RR Ohio River Bridge is much more impressive and well documented, but would be a tremendous modeling project in any scale. This relatively tiny bridge on a connecting branch line is suitably sized for the typical model railroad.
While ground-level photos of the bridge are hard to come by, satellite images available online provide enough details and perspective to capture the look of the structure. Aside from capturing the basic shape, replicating the side walkways and piping are essential to fully capture the flavor of this structure.
Begin with two Atlas Warren Truss Bridge kits. Cut and splice the basic structures to fit the exact length and height you need. This is a critical task that needs to be completed before starting the next step.
Benchwork for Bridges
Once you know the length of the bridge, the valley itself can be constructed. Special attention should go into supporting the bridge adequately and giving the tracks leading to it a strong foundation. With the bridge dimensions predetermined, you can prepare a space that's just the right size.
L-girder benchwork allows for flexibility when planning scenes like this.
- Support the track with plywood and the sub-roadbed with risers above a grid of beams.
- Provide for the bridge space by leaving a gap in the sub-roadbed.
- With the dimensions of the bridge already known, a plywood river base—slightly wider than necessary—can then be screwed directly to the girders.
- Install risers on either side of the bridge and trim the sub-roadbed to the exact length, making sure the bridge fits neatly in between without gaps. If necessary, you can trim the roadbed more during the next step.
Creating a Backdrop for the River Scene
A good backdrop delineates a river from a lake. And a river stretching toward the horizon adds a sense of distance to any model railroad. However, capturing that perspective requires either a very large layout or, in this case, a backdrop.
Adding a backdrop is really two projects in one. First, the backdrop must be built. Then, it must be supported. While there are many options for building a backdrop, in this particular project a styrene plastic sheet is used. The styrene curves easily with the back of the platform at the river's end.
Painting a backdrop is one of the most daunting tasks for beginner hobbyists. Even still, it's not as hard as you think. A few general steps and guidelines will get you going:
- Keep the horizon low. You're creating a river, not a waterfall. Keeping the waterline low makes the perspective more believable.
- Avoid direct lines of sight. Add a bend in the river or intersect the backdrop at something other than a right angle in order to give the viewer's eyes a distraction from the junction of horizontal to vertical scenery. This also forces the viewer to change vantage points to take in the whole scape. It can make the railroad seem larger, too.
- Try blending the colors of the backdrop. And always paint the sky, first—day or night. Once that's done, you can easily add the horizon and foreground details.
- The last layers painted should be the details closest to the front.
Even without any foreground scenery, the addition of your backdrop will completely change the way you look at your railroad. If you're not convinced you can pull off the paint job, enlarged photographs can also be used.
Supporting the Span With Abutments and Piers
Abutments and piers support the bridge and tie the model to the scenery. Poured concrete structures can be recreated with commercial castings or by using wood scraps.
- Start by making two abutments for your bridge from layers of luan plywood or scrap strips of basswood. Then, glue the two layers together to form the center section. Make the rear layer match the height of the bridge deck, then taper it at the top from a width slightly greater than the track itself to the exact width of the bridge. Make the front layer as high as the bottom of the bridge supports and as wide as the total bridge width. This provides a ledge to support the bridge.
- Create two winged walls made from additional strips of luan, angled at approximately 45 degrees on top. These walls should angle back from the center section and the adjoining edges can be beveled using a disc sander.
- Each of the winged walls should be specially cut to fit the scene, based on the prototype photos. Then, glue the pieces to the roadbed supports and the base, being sure to keep them perfectly plum. Fill any gaps with spackle, checking the bridge span frequently throughout this step.
- The center section of the bridge needs to be supported by two piers cut from scraps of 3/4-inch plywood. Height is a critical dimension, so make sure the piers will fit under the supports of the bridge without gaps. Determine the width of the piers by matching them to the width of the bridge itself. Then bevel the front of the upstream ends of the piers. All of the cuts should be made with a band saw or a small hand saw. Any areas that reveal plywood or other blemishes can be covered with a thin coat of spackle.
- With the bridge in place, carefully position the piers and mark their location on the river base. When finished, paint the wood to look like aged concrete.
Modeling the flow of water starts below the surface. Before installing the water, a riverbed must be prepped.
- Fill any joints, knots, or other blemishes with drywall compound. A light coat of compound over the entire riverbed will help hide wood grain.
- Paint the river using dark colors to represent deeper water. Blend the colors to provide a gradual change from shore to shore.
Using brown and black looks more realistic than blue unless you are modeling a seaport scene. You can also model the bottom of a shallow stream or tributary with dirt and rocks.
Modeling Water With Plexiglas
The easiest way to add water to your model railroad scene is to use a scrap of Plexiglas. Plexiglas works well for large, still bodies of water and waves can be added to the surface with resin or another commercial product if desired.
With Plexiglas, there is nothing to pour, so the results are easier to control. However, cutting the Plexiglas can be challenging and messy.
- Use a band saw with a thin blade and move quickly so you don't melt it.
- Once the Plexiglas is cut to shape, paint the edges black to help them disappear into the surrounding scenery.
- When the paint is dry, set the Plexiglas in place.
- Bring in the piers and bridge for another test fit. If all looks good, glue the piers in place and seal the edges of the Plexiglas with clear caulk.
Riverbank scenery begins with a frame. While there are many ways to make hills and mountains, hardshell techniques are common and easy to learn. Again, refer to your prototype photos to determine slopes, contours, and colors. Note where the ground extends above the track level to help correctly place the railroad and the bridge in the scene.
- Cardboard strips cut from old packing boxes can be used to create a web to support the plaster. Foam, newspaper, or wire screen material can also be used.
- When using cardboard for scenery supports, cut strips perpendicular to the sandwiched corrugation (i.e. across the ridges, not parallel with the troughs). This yields more flexibility and stronger strips.
- Use hot glue to join the strips, holding them in place with clothespins or spring clamps until they dry.
- It is easy to visualize and modify the shape and contours of the scenery at this stage. Simply cutting and splicing more strips will manipulate the outcome.
Hardshell Scenery for Riverbanks
The final step—a plaster skin—pulls the whole scene together.
- Cover the lattice frame you've created with paper towels soaked in Hydrocal plaster.
- Overlap the edges of the Plexiglas water to create a shoreline.
- Once the undercoat dries, add a topcoat made from mixed drywall compound or a similar material.
- After drying, the finished scenery can then be painted or stained with water or oil-based paints.