Gear Rack Elevator is a very smart LEGO Great Ball Contraption module from the GBC builder mickthebricker.

This LEGO ball machine works like a three steps stepper, but where each stage is relying on a distinct mechanism.

The first stepper from this cool LEGO ball machine is a non-motorized one: it carries GBC balls from the entry bin to the main ramp of the module and is only actioned by the main ramp.

The second and the third steppers are constituting the main mechanism of the GBC module. A central block underneath the exit ramp is moving up and down these two steppers, keeping a perfect synchronization thanks to the LEGO Technic racks located on each side of the LEGO GBC build.

This marble machine is capable to cope with a very large number of balls.

Reproduce it thanks to ready to build LEGO kits available on BuildaMOC.