model train set on track

Custom Built Animated Boxcars

e*Train Issue: Apr 2018   |   Posted in:

By John Barkley 75-7771, Larry Kaetzel 08-62813, Steve Lloyd 18-73326                                                                                            Spring 2018 

The original Aquarium Car had an animated display of fish swimming in an aquarium housed in a railroad car with windows so the fish could be seen. Since the original, “Aquarium Cars” have been produced where all sorts of things have been seen “swimming” around inside a railroad car with windows1. Wouldn’t it be fun to be able to customize an Aquarium Car to display images of anything you want? Imagine visitors’ reaction at seeing your family having a sumptuous supper with lighted candles on a “dinner” train running on your layout, or your church group caroling in Dickensian costumes. Imagine your hobby friends’ reaction seeing images of their layouts on a consist on your layout. Imagine how an animated car would attract attention to your table at a train show. The car could show items that would not fit on the top of your table.

To do this using a real Aquarium Car, one would have to create images on a clear filmstrip and a background image mounted on the frame around which the filmstrip rotates2. Most hobbyists don’t have the means to do this, and furthermore, the kind of animation possible with an Aquarium Car is limited. In this article, we share our efforts at creating a railroad car with any animation using a device you may have in your pocket as you read this.

So, you might ask, how can customized animation be added to a model railroad car? Our answer is to use a photo/video display device small enough to be attached to the car. There are at least two possible display devices: an MP3 player that can show video, or a Smartphone. For the railroad car, we chose a boxcar. We attach the MP3 player, or Smartphone, to some O gauge boxcars by affixing the device inside the boxcar. We describe the specifics of our approach below whose implementation we rushed because we wanted to have it in time for Christmas layouts.

Using an MP3 Player

Our first implementation used the Eclipse T180 1.8″ 4GB MP3 player which is available on Amazon for $12. This player easily fits thru the door of a 6464 size boxcar. The player is very light and can be held in place with Velcro that allows repeated removal and replacement.

This photo shows the MP3 player inside a Christmas boxcar.
The MP3 player is playing an abstract video of a set of different size blocks flowing about like snow in the wind, Christmas carols coming from the train. The boxcar was pulled around a Christmas layout adding color and action to the layout.

Limitations of the Eclipse MP3 Player

This technique works well, but the Eclipse MP3 player we used has limitations. Although the player’s display is easily seen, the display could be brighter, and has a standard definition, non-widescreen format, the format used by the old standard TVs. A modern widescreen high definition format video shows in the player’s display “letterboxed”, (the practice of transferring film shot in a widescreen aspect ratio to standard-width video formats while preserving the film’s original aspect ratio) i.e., the widescreen video is seen on the screen with black bars on the top and bottom.

Next, the sound output of the Eclipse goes to earphones and is not heard as a train runs. Our solution was to place a Smartphone on the train wrapped as a present riding in a gondola next to the boxcar carrying the MP3 player. The use of an online music service such as a Pandora “station” can provide a continuous playing of the desired music such as Christmas music.  So now, the sounds come from the direction of the player, but realize that the sound from the Smartphone may not be precisely synchronized with the video. 

Another limitation is that the Eclipse MP3 player only plays using an uncommon video format requiring conversion from the most common formats. Although conversion software to do this comes with the player, their conversion software requires an input format that is not the most common. So, another conversion is required and the software for this conversion is not supplied.

One more limitation is that organizing photos and videos for continuous play requires a cumbersome process with the Eclipse. It does not have the capability of playing a continuously repeating slideshow. This means that a video must be created to include all the photos and video to be shown.  From this initial video, a second video must be made consisting of several copies of the initial video so that the initial video repeats over a long period of time. You don’t want to have to stop a moving train to restart the video.

These limitations can be daunting for those without the knowledge or tools to create and edit video.

Using a Smartphone

Around the time we were working with the MP3 player, a hand-me-down iPhone 4 became available. A used iPhone 4 can be had for as little as $50. We are unaware of any Smartphone that can fit inside a 6464 size boxcar. However, a little research revealed that an iPhone 4 will fit into the MTH 50′ Ps-1 Double Door Boxcar (20-93692) and the MTH 40′ High Cube Boxcar  (30-74329). Like the MP3 player, the iPhone 4 fits into either of these through the door without modification to the car. We used the MTH Double Door boxcar. We missed an opportunity to use the MTH 50′ Double Door Plugged Boxcar with the Christmas lights (20-92133). This car would have really added real pizzazz to our animated car. The iPhone 4 is approximately 58 mm wide. This is also the approximate height of the opening when the MTH Double Door boxcar doors are open.

Now the question was how to hold the phone in place as the car is pulled along. We found that an almost spent roll of single ply toilet tissue, taped so that roll would not unravel, did the job just fine.

At first, we thought that the weight of iPhone 4 might make the boxcar list to one side. This turned out not to be the case. The MTH double door boxcar is sturdy, easily carrying the iPhone without a noticeable list, and the car did not need counterweights. Although we did not test this, we felt that the MTH car was robust enough to have iPhones on both sides of the car. However, the car with a single iPhone inside is heavy and best connected to a train right after the locomotive to avoid other cars on the train from listing as the train rounds curves.

This photo shows the double door boxcar with the iPhone 4 inside being pulled on a Christmas layout.

The video playing is an actual pace of an old time 4-4-0 locomotive filmed by the authors. The animated car, pulled around the Christmas tree, visually suggests that the toy train is pacing the video locomotive as viewed through the open doors of the boxcar.

Here is our implementation of an “Aviary Car” where the video is a finch aviary.

Notice that the doors of the MTH Double Door boxcar are open just enough so that the width of iPhone 4 display fits perfectly, and the entire widescreen format of the video is visible.

Configuring the Slideshow

The Photos App on an iPhone with iOS 9 works well and above supports the creation of a slideshow consisting of selected photos and videos within the Photos App. There is an option to enable the slideshow to repeat endlessly until manually stopped. Instructions for how to do this can be found in iPhone documentation. If the slideshow is to consist of a single video, it may be necessary to put two copies of the video into the slideshow’s album in order for the single video to repeat.

Because the iPhone is a wireless device, it is also possible to show live events. There are many live animal cameras, such as, the Giant Panda Cam at the National Zoo3. It is even possible to have live feeds of trains running on other layouts.

Other Smartphones and other Boxcars

We used an iPhone 4 for our implementation. An iPhone 5 or iPhone SE, among others, will also fit into an MTH Double Door boxcar, as long as the Smartphone’s width is approximately 58 mm. A used iPhone 4 can be obtained for around $50 and a used iPhone 5 can be obtained for around $100 from either Best Buy or Amazon. The MTH High Cube boxcar door height is approximately 68 mm and a Smartphone whose width is no more than 68 mm will fit. There are new Smartphones of the right width, e.g., BLU, an Android phone, that are available from Best Buy or Amazon for around $50. New Smartphones for that small a price will not have the same quality display as more expensive ones, but they may be adequate. We are not aware of any Samsung phones that will fit in any O gauge boxcar.

We presume that small Smartphones will fit into O gauge boxcars from other manufacturers. It is always best to verify that a specific Smartphone will fit into a specific boxcar by actually trying the fit as opposed to just relying on measurement. When considering any boxcar as a host for a Smartphone, the weight of the phone and its effect on the car should also be considered. Another consideration is how well the Smartphone display fits with the open doors of the boxcar. You want to check how much of the Smartphone display can be seen when the doors are fully open. For example, if an iPhone 4 is used with the MTH High Cube boxcar, the entire width of the Smartphone display cannot be seen through the open door.

The use of display devices on layouts is nothing new. Portable DVD players are often used as the screens of drive-in movies. In addition to their use to create animated cars, because of their small size, MP3 players and Smartphones can be used in many other places on a layout. They could show people dancing inside a ballroom in a hotel, or as a jumbotron at a stadium or casino sign.

Engineering a More Sophisticated Method

We have described a simple method of creating an O gauge animated boxcar. One of the key features of this method is the ability to quickly and easily insert an MP3 player or a Smartphone into a boxcar when you want to have an animated car on a train. After running the trains, the MP3 player or Smartphone is quickly and easily removed.

Unfortunately, the MP3 player has limitations and the Smartphone of the size we used are not in common use today. Most of the Smartphones in current use are too large to be inserted in any O gauge boxcar without significant modification to the car. Such modifications might include cutting a channel adequate for the phone to fit within the boxcar, and/or widening the doors.

We can envision an O gauge railroad car being engineered to accept the attachment of Smartphones in current use. We believe that the key feature of such a car would be quick and easy insertion and removal of the Smartphone. With such a car, when you wanted to add animation to a train, you would simply take your Smartphone out of your pocket, attach it to the car, and run the trains. Afterwards, remove the Smartphone from the car and put it back in your pocket. The idea is that the Smartphone you use everyday can be used to provide customized animation to your trains.


(1)  Too Many Fish in the Sea, an updated Article on Aquarium Cars, Bob Mintz
(2)  Animated Aquarium Car, Lionel Instruction Sheet, 71-6681-250,
(3)  Giant Panda Cam