Building an Authentic MOW Roster

MOW (or Maintenance of Way) trains are an essential yet often overlooked component of every railroad’s roster. Usually having the appearance of a somewhat normal freight consist to the untrained eye, MOW trains are quite literally the trains which keep the railroad running. In this article, we’re going to explore the different types of MOW trains commonly found, while linking to examples that you can add to your layout!

A Brief History

Maintenance trains have been around in one form or another for as long as railroads have operated. In the early days they were rudimentary, and relied heavily on manual labor. With relatively short distances between stations, the earliest maintenance trains were merely unpowered carts on rails. They could be pulled by horses or steam locomotives, and could even be pushed by hand if the distance to the worksite wasn’t too far! Rather than being equipped with machinery to assist in the job, they would mostly just carry tools and replacement parts.

As technology advanced, so did the MOW train. Throughout the 20th century, an increasing number of jobs were transitioned to machinery, which could handle tasks more quickly and efficiently, while also requiring a smaller crew. By the turn of the 21st Century, railroad maintenance had become largely automated. With the dawn of the computer age, many decades old practices became obsolete, with manual inspections typically being replaced by computerized sensors. Despite this, the jobs undertaken by MOW trains today are more varied than ever before, and the types of equipment used have evolved and expanded greatly.

Heavy Lifting

While most maintenance work was historically completed with visual inspections and manual labor, one early development in railroad maintenance technology was the crane car. These were some of the earliest mechanical additions to maintenance fleets, being usable for a range of purposes, from wreck clearing to tie placement. The earliest cars were unpowered, while later examples operated on steam. Some examples were even self-propelled. Today, crane cars have largely become obsolete, with most surviving examples belonging to museums. Their replacements include conventional construction vehicles with removable railroad wheels, and larger road-based cranes.

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Finding the Faults

Thanks to modern technology, maintenance work can today be performed on an as-needed basis. Tracks are regularly inspected, and a work order is created if an issue is found. Most railroads have sophisticated equipment to do this job, however the type of equipment they use can vary greatly. Most Class One railroads have a consist called a Geometry Train in their roster. Loaded with sophisticated monitoring equipment, these trains travel the system continuously checking track curvatures, alignment, and smoothness. Some railroads such as CSX and BNSF utilize retrofitted transition era passenger cars hauled by conventional locomotives for this purpose, while other railroads such as Union Pacific and Canadian National utilize self-propelled railcars. These are either specially designed cars, or former Budd RDC passenger railcars.

The types of issues these cars monitor for are fairly rare, and as such most railroads don’t require more than one or two in their roster. For smaller railroads, the need is even less. Most Class II and III railroads will typically use more traditional visual observation practices for kinks and alignment issues, utilizing a Hi-Railer truck (a pickup truck with railroad wheels installed). For more comprehensive checks, they will contract out to a third party or utilize the Federal Railroad Administration’s equipment.

While these trains are essential for finding external issues, internal cracks and rail fractures also need to be monitored. For this task, a vehicle known as a Sperry Railcar is used. These are perhaps some of the most unique and remarkable MOW vehicles. Made up of former gas-electric Doodlebugs pushing 100 years in age, these cars have been heavily modified to include sensors and x-ray systems that can see inside rails. They are critical for finding cracks and stress points before they become a problem. Sperry also employs a fleet of Hi-Railer box trucks to compliment their railcar fleet, and contracts with just about every railroad across the United States.

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Laying the Groundworks

One of the most common types of MOW train seen traversing the rails is the ballast train. Made up of specially designed hoppers, these trains are critical to the process of laying fresh ballast, and replenishing ballast on existing track segments. Like geometry cars, ballast hoppers are a part of every railroad’s roster. However unlike geometry cars, they are much more widely and frequently used – one railroad’s fleet can in fact comprise of hundreds of cars! Operationally, ballast cars work in similar ways to standard stone or coal hoppers, featuring an open top for loading, and chutes for unloading (or deploying in this case). They will be run at slow speeds as they lay ballast, and can be controlled from a single location to either open or close as needed. More modern examples are even solar powered!

Every railroad typically retains a fleet of ballast cars, with smaller railroads utilizing older cars or retrofitted stone or coal hoppers. Most short line railroads will have just one train of ballast cars, and some even function with just a single car! Both large and midsized railroads will supplement their own equipment’s availability by contracting out ballast work out to third parties such as Herzog, who maintain their own fleets of hoppers.

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Making Tracks

Much like ballast, rails and ties are also typically transported to the worksite by rail. Jointed rail segments and ties are commonly carried in gondola cars, while welded rail segments are transported using specially designed welded rail trains, similar in appearance to a train of log flats. Both types of car are usually equipped with a form of maintenance equipment to offload and position the materials. For tie gondolas, this can be a standard Caterpillar Excavator that has simply been placed inside the car. For larger railroads, the use of a Herzog Tie Train is typically employed. This is a specially designed consist of retrofitted intermodal well cars with their own distinctive rebuilt locomotive. They feature a trolley which can roll up and down the length of the train while carrying a Caterpillar Excavator, allowing access to multiple cars at once. The excavator can remove and replace ties even while the train is positioned over them!

Once the ballast, ties, and rails have been installed, the tracks must be secured in place. For this, a machine known as a tamper is used. Tampers do exactly what they say – they tamp the ballast down, compressing it between the ties and rails to provide a more condensed, secure trackbed. These come in all shapes and forms, with some being as long as a conventional locomotive, while other typically older examples are only a little larger than your average sedan.  Older examples are usually found on smaller railroads, often passed down from larger operators, while the largest examples can be found on higher priority lines where the security of the trackbed is key to the safety of the line.

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Join the Conversation

While we’ve covered the basics, there are still many more types of MOW equipment which are used in the day-to-day maintenance of railroads. These range from ballast undercutters (which remove life-expired ballast from existing tracks), to rail grinders (which grind the railheads to ensure a smooth, even surface). What types of MOW equipment do you run on your railroad? Send us a photo of your consists via social media and we’ll share it on our page!