How to Make a Train Tunnel Out of Styrofoam

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model train memeHave you ever wanted a train tunnel for your model railroad but didn’t want to spend the money?

Or maybe you’ve tried to make one out of cardboard or wood and it just didn’t turn out right.

Well, I have the perfect solution for you: a train tunnel made out of Styrofoam!

This tutorial will show you how to make a realistic-looking train tunnel using only a few basic tools and supplies.

Let’s get started!

First 2 Awesome Facts On the Subject

  1. New Jersey, a railroad world, built of 52,000 feet of track. “The world’s largest model railroad, ‘Northlandz,’ includes over 8 miles of track and features impressive mountains, valleys, tunnels, and bridges, all built primarily with styrofoam and other lightweight materials. The level of detail and realism achieved in this massive layout demonstrates the potential of styrofoam in model railroading.” – The New York Time

  2. “The Walthers Cornerstone Series Mountain Division Tunnel Portal is an example of a high-quality styrofoam train tunnel product. It is designed to replicate a prototypical concrete tunnel portal and is lightweight, durable, and easy to install in any model railway layout.” – Walthers Model Railroading

Gathering Your Materials

styrofoam tunnel

Typically, for this project, here’s a quick shopping list:

  • Styrofoam board (1/2 inch thick)
  • Ruler or compass
  • X-ACTO knife or box cutter
  • Pencil
  • Sandpaper (220 grit)
  • Spray paint (optional)
  • Elmer’s Glue or hot glue gun
  • Clamps (optional)
  • Model trains (optional)

If this has already got you feeling lazy because of the effort ahead. We’ll give you fair warning, this takes a bit of time and effort. This is not for the impatient! 

For the lazy ones, we have a quick hotfix solution at the end of this article.

No shame in either approach. We won’t tell anyone (we promise).

Styrofoam sheets

Choose sheets with at least 1-inch thickness to ensure stability and durability. You can find these at most craft stores or online.

“Styrofoam can be carved and shaped to create stunning landscapes and intricate details for model railroading. It is an excellent material for making mountains, valleys, tunnels, and other terrain features because it is lightweight, easy to work with, and can be painted to replicate various natural elements.”Model Railroader Magazine

Cutting tools

A hot wire cutter is the best option for cutting styrofoam, as it melts the foam and creates a smooth finish. You can also use a utility knife or a serrated blade.


Use a glue specifically designed for styrofoam or a low-temperature hot glue gun to avoid melting the foam.

Paint and paintbrushes

Acrylic paints work well for styrofoam projects. You’ll need a variety of paintbrushes for different effects and textures.

Base material

A sturdy base, such as plywood or foam board, will help support the weight of the train and tunnel.

Creating the Train Tunnel Structure

Cutting the styrofoam sheets

Draw the desired tunnel shape on your styrofoam sheets, including the entrance, exit, and side walls. Use your cutting tools to carefully cut out the pieces.

Assembling the tunnel pieces

Once you’ve cut the styrofoam pieces, dry-fit them together to ensure a proper fit. Then, apply adhesive to the edges of the pieces, and press them firmly together. Hold the pieces in place until the glue sets. You may use masking tape or pins to keep the pieces secure while the adhesive dries.

Attaching the tunnel to the base

Position the assembled styrofoam tunnel on your base material, ensuring it’s in the desired location. Apply adhesive to the bottom edges of the tunnel, and press it firmly onto the base. Allow the glue to dry completely before proceeding to the next step.

Painting and Decorating Your Styrofoam Train Tunnel

Choosing the right paint

As mentioned earlier, acrylic paint is an excellent choice for styrofoam projects. Select colors that resemble the natural environment you’re trying to replicate, such as shades of gray for rocks or shades of green for moss.

Applying paint

Start by painting the entire tunnel with a base coat of your chosen color. Allow the paint to dry before applying additional layers or details. Use a variety of brush sizes and techniques, such as dry brushing or stippling, to create textures and visual interest.

Adding details and textures

To make your styrofoam train tunnel look more realistic, consider adding details like rock formations, moss, or grass. You can use small stones, modeling grass, or even crumpled aluminum foil to create texture. Attach these materials using adhesive or paint, and then blend them into the surrounding environment with matching paint colors.

Caring for Your Styrofoam Train Tunnel

Proper care and maintenance will ensure that your styrofoam train tunnel lasts for years to come. Keep it away from direct sunlight, as prolonged exposure can cause the styrofoam to deteriorate. Also, avoid exposing it to extreme temperatures or moisture, as these conditions can damage the structure and paint. Clean your train tunnel by gently dusting it with a soft brush or cloth.

How do you make a train tunnel portal?


1. Gather Your Materials

Before diving into the project, make sure you have the following materials on hand:

  1. Styrofoam, plaster, resin, or wood (choose the material that best suits your needs and skill level)
  2. Cutting tools (hot wire cutter, utility knife, or saw, depending on your chosen material)
  3. Adhesive (choose a glue that works well with your selected material)
  4. Acrylic paint and paintbrushes
  5. Sandpaper or emery board (optional)
  6. Ruler and pencil
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10/05/2023 11:02 pm GMT

2. Design Your Tunnel Portal

First, let your imagination run wild and sketch out your tunnel portal design on paper. Look up real-life tunnel portals or existing model railroad designs for inspiration. Don’t forget to consider the scale of your model railroad and the dimensions of the tunnel.

3. Bring Your Design to Life

Once you’re happy with your design, it’s time to transfer it onto your chosen material. Using a pencil and ruler, carefully draw the outline of the tunnel portal, including the entrance, side walls, and top arch.

Now, carefully cut out the tunnel portal using the appropriate cutting tools for your material. Be patient and take your time, as precision is key to achieving a realistic look.

If needed, use sandpaper or an emery board to smooth out any rough edges.

4. Assemble the Tunnel Portal

With all the pieces cut, it’s time to put them together. Apply adhesive to the edges of the pieces and press them firmly together. Hold the pieces in place until the glue sets, or use clamps if necessary.

5. Add a Splash of Color

Acrylic paint is perfect for adding a touch of realism to your tunnel portal. Choose colors that match the surrounding landscape, such as shades of gray for a rocky appearance, or shades of brown for a more earthy look.

Start by painting the entire tunnel portal with a base coat of your chosen color. Allow the paint to dry before adding additional layers or details. Experiment with different brush sizes and techniques, such as dry brushing or stippling, to create texture and visual interest.

6. Install the Tunnel Portal

Finally, it’s time to install your masterpiece in your model railroad layout. Position the tunnel portal at the entrance of the train tunnel and use adhesive to secure it in place. Be sure to double-check that the placement is correct before the glue sets.

And there you have it—a beautiful, realistic train tunnel portal to enhance your model railroad. Enjoy the satisfaction of having created a unique and eye-catching feature for your layout!

How do you make a HO scale tunnel?

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10/05/2023 07:53 am GMT

First, you’ll need a large sheet of Styrofoam. You’ll need this for the inside walls of your tunnel. This will help you create smoother walls and allow you to place larger pieces of Styrofoam inside for walls. If you don’t have a large sheet of Styrofoam, you can always buy premade tunnel walls in OO or N scale.

Next, you’ll need to cut a piece of Styrofoam two inches thick. You can find the material in big blocks or two-inch sheets. Use a cutting tool to cut the piece into the desired size and shape, and then glue together the pieces. If you want a larger train tunnel, you can stack several two-inch pieces together.

You’ll need to create a gradient. Depending on the scale, a steeper slope can be more difficult. In HO scale, a single locomotive can pull up to nine Overton passenger cars, but if you need to pull more than that, you can add a second locomotive to pull the entire train.

How to make straight tunnels?

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If you’re a beginner and want to make a straight tunnel for your model train, there are a few simple steps you can take. First, you’ll need to cut a piece of cardboard about five feet long. You can use a hobby knife or box cutter to cut it into three pieces. Next, cut out a small square from the top piece to make a window. Then, duct tape these pieces together. You’ll also need a small piece to make the door.

You’ll also need to cut the tube twice as long as it is tall so you have plenty of vertical clearance for trains. Cut the tube about half-way around on both sides. Once this is done, place it over the track. Once you’ve got it in place, you can build up the sides and top with papier-mache or plaster. You can also decorate the inside of the tube.

Feeling Lazy? Here’s The 3 Best Ready-Made Options


Q: Can I use spray paint on styrofoam? A: It’s not recommended to use spray paint on styrofoam, as the solvents in the paint can cause the foam to dissolve or melt. Stick to acrylic paints for best results.

Q: How can I make my styrofoam tunnel more sturdy? A: You can reinforce the structure by adding additional layers of styrofoam or by inserting wooden dowels or skewers into the foam for added support.

Q: What other materials can I use to create a train tunnel? A: Some alternatives to styrofoam include plaster, cardboard, and papier-mâché. Each material has its pros and cons, so choose the one that best suits your needs and skill level.

Q: Can I use styrofoam tunnels for outdoor model railways? A: Styrofoam is not ideal for outdoor use, as it can deteriorate under extreme weather conditions. Consider using materials like concrete or plastic resin for outdoor train tunnels.

Q: How do I create a realistic-looking entrance and exit for my tunnel? A: To create a realistic entrance and exit, add details such as rock formations, vegetation, and weathering effects. This can be achieved using paint, modeling materials, and creative techniques like dry brushing and stippling.