GBC Module Catalog
The most comprehensive listing of Great Ball Contraption modules
Recently Updated Modules
Queen Watevra’s Magical Ball Mover
Tales of Space
RFID Ball Tracker
Uses modified balls embedded with an RFID tag to track loop travel times in a layout.
Perpetual Motion
Little Black Stepper
Ferris Wheel
Ball Coaster
Ball Counter
7 Segment Ball Counter
Ball Dozer
Construction Elevator
About the Great Ball Catalog
Great Ball Contraptions (GBC) modules are custom-built LEGO machines that transport small LEGO balls through creative mechanisms.
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.