As you’d expect, LEGO has a variety of kits to build heavy construction equipment. But, in keeping with the LEGO System, they’re all designed at the same scale we’re all used to. Matt Denton isn’t satisfied with that scale, so he’s been building huge versions of LEGO kits. His latest creation is a giant RC LEGO bulldozer, and it’s his most impressive build yet.
This is a 5:1 scale version of the classic LEGO Technic 856 Bulldozer that was originally released in 1979. In total, there are 372 individual pieces, and they took 600 hours of 3D printing on a Lulzbot TAZ 6, a TAZ 5, and a Lulzbot Mini. Everything was printed in PLA, with the only exception being steel dowel pins in the tracks and the electronic components. Denton has provided his STL files on Thingiverse, so you can build your own if you have the patience!
To convert the bulldozer to radio control, he used a simple RC receiver that connects to an Arduino and an amplified motor driver. The motor driver powers two DC motors, which in turn drive the tracks. The Arduino is used to recreate the sound of a bulldozer engine with a clever program that increases both the volume of the engine noise and the RPM as the throttle is pushed. The finished bulldozer is impressive, and if you’ve got enough time on your hands you can build it yourself.