How to Build a Model Train Tunnel

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How to Build a Model Train Tunnel

As you are building a model railroad layout, planning before you begin is essential. One of the things that you should incorporate in your planning process is building railroad tunnels and bridges.

As you are dealing with challenging layouts, building model train tunnels can help you to create a better experience for people who are on the train. This is done by hiding your trains from plain view with the use of a tunnel during a part of their journey.

If your trains can be seen in plain sight at all time, the people in the train will feel that they are not traveling from one place to another.

It is essential that you create a good experience for people on board the train. By building a model train tunnel, you can make it seem that they are traveling from the hidden valley and then disappearing again into another tunnel. This way, they can feel like they are travelling somewhere.

What do you need to make your model train tunnel?

Firstly, you can either purchase or choose to make the tunnel portal yourself. Most of the tools that you need to create a model train tunnel can be found in any hobby shops. Paints, plaster casts or resin casts which are commonly used in building a model train tunnel can be purchased at shops. If you feel like it, you can also make your own plaster cast or resin cast.

There are several options that you can use to make the body of the tunnel.

  • Styrofoam

By using a sheet of Styrofoam, you can cut and build the walls of the tunnel. The track that you build will most probably be curved. With a Styrofoam, you can curve the sheet to match the course of the track. A Styrofoam can also be used to cover the top part of your walls.

You can utilize beaded Styrofoam which comes in boxes and are usually used for packing materials. You can also cut it with a sharp knife to form the tunnel portal. A Styrofoam is usually used as a base material for model railways. You can also cut it into different shapes and forms.

Styrofoam is easily available at hobby shops or any local hardware stores. As an additional tip, it would be great for you to have an idea of what shape you want from your model train tunnel so that you can save money by purchasing the right Styrofoam.

  • Wadded newspapers

You can cover the track directly with the use of wadded newspapers. Then, you can cover those newspapers using a cellophane tape. Spray on the cellophane surface and make sure to leave openings which marks the starting and ending of your tunnel. This will take some time to dry so you should leave it for at least 24 hours.

For the best result, make sure you do not touch it until it is fully dry. Using a knife, you can also shape the top of the mountain and add the plaster cloth for better texture. The plaster cloth also provides a great surface for you to paint on.

  • Cardboard web technique

To utilize this method, use wadded newspapers to form the sides of the top of the tunnel. As a finish to your mountain form, utilize the plaster cloth. Remember to estimate the inner side of your tunnels correctly so that your train can fit in well.

If you fail to do this, you might have to make the opening bigger and spend more time changing it. When painting, utilize concrete color palettes and add gray or black wash to enhance the look of your train tunnel.

How should you build the inside of your model train tunnel?

As we have discussed the external part of the model train tunnel, you should not neglect the inside of your tunnel although it is not visible from the outside.

To do this, take a piece of any solid color construction paper and cut it to a proper size. Once you have done this, insert the rolled paper into one end of the tunnel. Then fold it and position it to create a rounded effect inside the tunnel.

To build the inside of your model train tunnel better, you can utilize rock castings for your inside walls. To add more colors on the inside, paint it with concrete colors.

How do you maintain access to the inside of your model train tunnel?

Under the Murphy’s Law, any track location on your model train tunnel which has poor access will cause train derailments. This won’t be much of a problem if your tunnel is relatively short. The way that you can see if your tunnel is short is if you can use your fingers to pull out any train cars that are derailed. However, if your tunnel is too long, here are several ways for you to increase access to your track.

1.  Cut and access hole to the inside of your tunnel area

You should do this from the bottom so that you can reach in from the bottom of the layout. This way you can easily grab any derailed cars or trains.

2.  Make sure to use cellophane as the mountain base

By doing this, you can lift the mountain for you to access your track. Use cellophane tape at the base of the mountain before you use plaster cloth.

3.  Cut a hole in the side of the mountain

Once you cut the hole, cover the gap with a plaster rock casting. Whenever you have a derailment, pull the rock out and grab the derailed car. You can easily fix the scenery by putting the rock back in its place.

What’s next?

Now that you are done with creating your tunnel, place your tunnel portals at the end of each tunnel and seal in any remaining spaces. Rock casting should be placed on either side of the portal if you wish. For further effect, you can also create a rock wall or retaining wall which leads up to the tunnel.