It Takes a Lot of Thought and Planning to Paint a Train
Over the last 50 years, Amtrak has seen many designs come and go.
...“Airlines have it easier because the plane is a stand-alone vehicle,” he says. “But a train is made up of different pieces of equipment coupled together, and they’re mixed around often.”
Designing a paint scheme for a locomotive that can seamlessly match up with different types of cars is key. It also needs to look right from a distance, as a train rolls across the landscape, and up close for the passenger standing next to it at a station. The paint also has to stand up to the rigors of traveling thousands of miles back and forth across the country. Donnelly says that while Amtrak tries to keep its equipment clean, moving passengers is the primary goal, and that sometimes means going a long time between visits to the train version of a car wash (what the railroad calls a “wash rack”). To deal with that, designers try to figure out what parts of a locomotive accumulate the most dirt, and then use darker paints to mask those areas. That’s why the roof and the areas around the wheels are often black or gray. Another factor is what manufacturers provide; if a part only comes in one color (usually something neutral like gray) it ought to be incorporated like that into the final scheme for ease of maintenance.
“It’s not just like creating a piece of art,” Donnelly says. “A locomotive or passenger car is a functioning tool.”
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https://www.atlasobscura.com/articles/amtrak-paint-designs