For those of you who are looking for a project to really test your 3D printer’s capabilities, look no further. The 3d printed 4-8-8-4 Big Boy Locomotive model is six feet long and was created by Paul Fischer of Maryland (uploaded by MakerBot). Fischer spent nearly 800 hours drawing up the train in Solidworks and another 1,000 hours printing the impressive beast on a MakerBot Replicator 2.

Apparently, during the late 1930’s Union Pacific enlisted the help of their “Department of Research and Mechanical Standards” (DoRMS) to design a locomotive that could pull a 3600-ton train unassisted over the 1.14% grade of the Wahsatch.  The locomotive was manufactured between 1941 and 1944 and was operated by the Union Pacific Railroad until 1959. The Big Boy fleet totalled twenty-five locomotives that were used primarily in the Wyoming Division to haul freight over the Wasatch range between Green River, Wyoming and Ogden.


It took around 16 rolls of MakerBot’s True Black PLA filament and an excessive amount of super glue to produce the impressive model. Fischer said “In the middle of the night I would hear the printer stop, and I would get up and start a new build.”

For those of you wanting a challenge the 4-8-8-4 Big Boy locomotive is the perfect project for you. The files can be found on Thingiverse but it’s worth noting that the project is not for the faint of heart or those who have limited time.