RenLUG

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RenLUG – Central Florida’s LEGO® User Group

An inclusive adult LEGO® community for serious builders, creators, and collaborators — inspiring builders since 2019.

RenLUG brings Adult Fans of LEGO® (AFOLs) together to build, learn, and share — from personal MOCs to large-scale collaborative creations, public exhibitions, hands-on STEM programs for kids and families, and community partnerships across Central Florida.

Wherever we can, RenLUG puts bricks in people’s hands — not just on display. Our Play Brick Build Zone lets visitors free build or tackle creative challenges, while Royal Rally Racing has kids — and more than a few adults — designing and racing their own LEGO® gravity cars.

RenLUG serves the greater Orlando metro region — core membership in Seminole, Orange & Lake Counties, with programs and events spanning nine counties and 9,500+ square miles across Central Florida. See our full service area →

Why RenLUG?
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2026 Calendar – Events & Workshops
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RenLUG Great Ball Contraption

Engineering Chain Reactions with LEGO®

A group of three people, including a young boy and a toddler, are observing a LEGO display at an event. One adult is holding the toddler, while another adult, wearing a 'RenLUG' shirt, is speaking. The display features various LEGO creations and is set up on a table covered with a blue tablecloth.

A Great Ball Contraption — GBC — is one of LEGO® fandom’s most remarkable collaborative engineering traditions. Each module is an independently designed machine with one job: receive a ball from the previous module, move it using any mechanism imaginable, and pass it to the next. Chain dozens of modules together and you have something that stops crowds completely — a looping, whirring, endlessly surprising mechanical exhibit that demonstrates engineering creativity in the most visible way possible.

No two GBC modules are the same. No two loops run exactly the same way. That’s the point.

RenLUG’s GBC Program

RenLUG operates an active and growing Great Ball Contraption program — one of the most developed in Florida. Our members design and build their own GBC modules independently, then bring them together at events throughout the year to run as a collaborative loop.

RenLUG’s roots in FIRST LEGO League run deep — our founding members came through FLL, and that background in sensors, programming, and iterative engineering design isn’t just history. It’s why our GBC program and our approach to automated systems go beyond display-level building into genuine engineering education.

In 2026, RenLUG is bringing GBC to events across Central Florida — including introducing it for the first time to Brick Convention Orlando. We also host a dedicated annual GBC Day at the University of Central Florida, combining collaborative engineering with youth engagement and hands-on STEM learning.

A diverse group of five individuals, including both adults and teenagers, gathered around a yellow table engaged in a robotics project, demonstrating collaboration and learning in a colorful classroom setting.

Why GBC Works for STEM Learning

A group of people, including children and adults, viewing a colorful display of LEGO creations at an event. The scene features various LEGO models, including a roller coaster and miniature buildings, set on tables in a large room.

A GBC exhibit isn’t something you walk past — it’s a living machine that runs continuously, inviting people to stop, trace the path of a ball through a dozen different mechanisms, and ask how each one works. For young visitors, especially those encountering engineering concepts for the first time, GBC makes abstract principles immediately visible and tangible.

Through building, observing, and troubleshooting the GBC, participants:

  • Explore mechanical engineering concepts including energy transfer, gear ratios, and motion control
  • Experience the engineering design process — plan, build, test, and iterate
  • See that engineering can be imaginative, artistic, and collaborative — not just technical
  • Develop confidence in STEM creativity, guided by adult mentors and experienced builders
RenLUG’s GBC Workshop at UCF, Spring 2026

RenLUG’s GBC installations are designed to be welcoming and accessible to participants of all ages and backgrounds. We encourage everyone to engage — and we particularly welcome the opportunity to show girls and young women that engineering is a field where creativity and curiosity belong. By turning motion into a mesmerizing chain reaction, GBC captures the spirit of engineering: curiosity, creativity, and collaboration — and empowers young people to see themselves as the next generation of innovators, engineers, and makers.

2026 GBC Event Calendar

  • February 7 — Rockstar Robotics STEM Outreach Boys & Girls Club, Walt Disney World Clubhouse (GBC brought as a hands-on engineering illustration tool for multiple youth robotics teams as part of collaborative STEM outreach with Rockstar Robotics)
  • February 14 — Spark STEM Fest: Science Night Live Orlando Science Center (Single GBC module on static display as part of RenLUG’s broader exhibit)
  • March 29 — LEGOpalooza! Orlando Public Library, Melrose Center (Full GBC loop as part of RenLUG’s interactive public exhibit)
  • April 18 — Members GBC Workshop Meeting University of Central Florida (Members and invited guests only)
  • May 2–3 — Brick Fan Event Orlando Dezerland Park (Modules integrated into collaborative display)
  • June 6–7 — Brick Convention Orlando Central Florida Fairgrounds (RenLUG introduces GBC to this event for the first time)
  • July 11 — LEGO® GBC Day at UCF University of Central Florida (Dedicated public GBC event with youth engagement)
  • November 6 — Maker Faire Orlando: Field Trip Day Central Florida Fairgrounds (Full GBC loop — hands-on STEM demonstration for school and homeschool groups)
  • November 7-8 — Maker Faire Orlando Central Florida Fairgrounds (At minimum a single recirculating GBC module; full loop planned — Maker of Merit 2025, returning)

Building With Us

RenLUG members design and build their own GBC modules as individual projects, then contribute them to the group loop at events. There are no experience requirements — builders at every skill level participate, from first-time module designers to experienced builders running complex multi-stage machines.

If you’re an existing member interested in contributing a GBC module, connect with us on Discord. New to GBC entirely? Resources and building standards are widely available through the AFOL GBC community and we’re happy to help you get started.

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Bring GBC to Your Event

RenLUG’s GBC exhibit is available as part of larger event bookings across Central Florida. GBC works best alongside our other programs — paired with Royal Rally Racing for a complete interactive STEM experience, or as a standalone engineering exhibit at conventions, science centers, and community events.

Request a GBC Event → Learn About Royal Rally Racing →

RenLUG Great Ball Contraption – Engineering Chain Reactions with LEGO®

The Great Ball Contraption (GBC) is an interactive, collaborative LEGO® engineering exhibit that demonstrates core principles of mechanical design, energy transfer, and systems engineering through motion. GBC hands on workshops developed and presented by RenLUG (Renaissance LEGO User Group), this large-scale kinetic sculpture engages participants, especially girls and young women, in creative problem-solving while showing that engineering can be imaginative, artistic, and fun.

A GBC consists of a series of individually engineered modules, each designed to move small LEGO® balls through a continuous loop using gears, levers, conveyors, and lift mechanisms. Each builder’s module must meet precise design and timing requirements so it can connect and work seamlessly with others – mirroring the collaborative, interdisciplinary nature of real-world engineering projects.

GBC and the Age of Intelligent Systems

The Great Ball Contraption has always been about systems — how individual parts, each doing their own job, combine into something smarter and more capable than any single module alone. That’s not just a LEGO® concept. It’s the foundation of how modern engineers think about automation, robotics, and artificial intelligence. Each GBC module is essentially a small machine solving a defined problem and handing off its result to the next — a physical, tangible model of how networked systems, feedback loops, and collaborative automation actually work. As LEGO® celebrates innovation and intelligent design in 2026, the GBC sits at the natural intersection of creative building and the engineering principles that power today’s most exciting technology. For young visitors watching the balls loop endlessly around the table, it’s not just a cool machine — it’s a first glimpse at how the world they’re growing up in actually works.

Through building, observing, and troubleshooting the GBC, participants:

  • Explore mechanical and electrical engineering concepts, including energy conversion, gear ratios, and motion control.
  • Learn the engineering design process—plan, build, test, and iterate.
  • Experience the power of collaboration, as every module’s success depends on teamwork and communication.
  • Gain confidence in STEM creativity, seeing firsthand that engineering can blend art, movement, and innovation.

RenLUG’s GBC installations are featured at major community STEM events, such as Spark STEM FEST, School STEM Nights and the Orlando Science Center’s STEM Showcase, where hundreds of young visitors, many first-time builders, are invited to help troubleshoot or design their own modules. The activity particularly encourages girls to explore engineering roles in a playful, supportive setting, guided by adult mentors and experienced builders who model inclusive participation in technical fields.

By turning motion into a mesmerizing chain reaction, the Great Ball Contraption captures the spirit of engineering: curiosity, creativity, and collaboration. It empowers girls to see themselves not only as participants in STEM, but as the next generation of innovators, engineers, and makers.