GBC Module Catalog
The most comprehensive listing of Great Ball Contraption modules
Recently Updated Modules
This Is Fine
Bling Colour Sorter
Trophy Stepper
This is the 2021 Brickslopes Workshop Module. Visit the Rebrickable page to get a download link for the instructions.
DoubleGBCube
Pump Module Version 2M
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About the Great Ball Catalog
Great Ball Contraptions (GBC) are intricate LEGO machines that transport small balls through creative mechanisms and modules.
This catalog is the world’s most comprehensive resource for GBC modules, featuring hundreds of modules from dozens of builders, a lot of them with build instructions. Whether you’re a seasoned builder or just discovering the hobby, you’ll find hundreds of unique designs to explore and build.
Start browsing to discover the amazing variety and ingenuity of the global GBC community.