Product Idea |

Union Pacific "Big Boy"

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Make way for the Big Boy
Spanning 40 meters (132 ft 9¼ in) and weighing 548 tons (1,208,750 lb), The Union Pacific 4006 has been given the accurate nickname “Big Boy”. The steam locomotive produces a mind-boggling 6290 horsepower and to this date holds the record of largest and most powerful steam locomotive in the world! The Big Boy is quite a spectacle too, with the numerous mechanical valve gears spinning and plumes of steam and smoke blasting out from every little hole. 


The crown jewel
Given LEGOs history of iconic train sets, the U.P. Big Boy must be the crown jewel. Since it has never been produced as an official set, I decided to take matters into my own hands. I present to you: The Union Pacific 4006 “Big Boy”. A locomotive this large presents a lot of challenges; most of which concerning structural integrity. Though this model is mainly a display piece, it was all along very important for me, that the train fits standard LEGO tracks, and that it actually works. 38 wheels is an insane amount on a single model. So to make the thing turn tight enough, I’ve divided all wheelsets into individual articulating sections, that still support the weight 2100 LEGO pieces. And if that isn’t enough, I made the valve gears functional as well, since it’s such an iconic part of any steam locative.


The perfect LEGO set
You don’t have to be into trains to find the Big Boy impressive. The final model is absolutely huge and makes for a great living room centerpiece as well as a great train playset. I wanted to make the Big Boy ever since my dad bought a functional scale model of it. It was about the coolest thing ever! Building the train is also going to be an experience, with lots of mechanical parts, interesting (and legal!) techniques, and tons of pieces.


Getting this model approved would be a dream coming true! If you like what you see please help me reach 10.000 supporters. Feel free to share with your friends and train enthusiasts. Please don’t hesitate to contact me if you have any questions whatsoever, I’d love to hear from you! 


Set includes:
 Union Pacific “Big Boy” locomotive and tender.
 Display stand (info sign coming soon).
 1 minifig


The model is built and rendered using stud.io and part designer. As of now, the model is not compatible with power functions, though I’m working on it. Stay tuned for future updates.