
GBC Module Catalog
The most comprehensive listing of Great Ball Contraption modules
Recently Updated Modules


REF06 - Mia�s Friendly Wheel

REF09 - Rotating Truss

MOD04 - Avengers Tower

MOD01 - Compact Reservoir
This Compact Reservoir is a modified version of the BW 2018 Ball Pump by Brian Alano. I wanted to build a small...

Wheel 36
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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.