Infinite LEGO Candy Factory: When Technic, Mindstorms, and Sweet Engineering Click

A mesmerising closed-loop production line that sorts, dispenses, and recycles candy—plus practical tips and MOC ideas to build your own

If you’ve ever watched a real factory and thought, “I want that… in LEGO,” this one’s for you. The “Infinite LEGO Candy Factory” showcases a complete, self-sustaining production flow: candies are sorted, orders are picked, portions are dispensed, and the leftovers are whisked back onto a conveyor to be re-sorted—again and again. It’s the kind of build that blends the best of LEGO Technic mechanics with programmable logic (LEGO Mindstorms or similar control electronics), turning a simple treat into a hypnotic dance of belts, hoppers, gates, and sensors. The result isn’t just a machine; it’s a systems-engineering lesson wrapped in studs. Watch the original “Infinite LEGO Candy Factory” video for the full spectacle. 

What makes this model so addictive is the loop. Most LEGO machines are linear: input on one side, output on the other. Here, the “output” becomes the “input” again through a clever recycling conveyor. That feedback loop means the machine can run indefinitely, which forces the builder to solve real industrial problems at miniature scale: jam prevention, throughput balancing between modules, consistent dosing, and sensor calibration. Articles that covered the build note that it combines Technic hardware with Mindstorms-class control and some custom electronics—a common recipe in advanced LEGO automation that gives you the torque, timing, and sensing to pull off reliable motion. 

You can treat the whole setup as a series of micro-modules: a hopper that meters candy one by one; a sorter that separates by color or size; a picker that fills “orders” (e.g., N red + M blue pieces); a transfer system that parcels out the goods; and a return line that closes the loop. Each module has a clear purpose and interface, so you can swap parts, tune speeds, and upgrade logic without tearing down the whole system. It’s also a perfect playground for experimentation: try different belt textures, chute angles, or gear ratios; swap optical sensors for weight-based triggers; or rewrite the control program to prioritise different orders. Once you see it as a kit of interoperable factory “organs,” it becomes far easier to design, debug, and scale. And because the machine cycles forever, even tiny improvements are obvious—you’ll immediately see when jams disappear, flow smooths out, and the rhythm locks in.

Below, you’ll find practical tips for building a reliable candy-handling line, followed by a bunch of MOC ideas that use the same techniques—whether or not you include actual candy.

Tips: How to Build and Use This Technique

• Start modular. Build and test each stage alone (hopper → gate → sorter → dispenser → return). Only link modules once they’re stable at the intended speed.

• Design for flow, not force. Candy prefers sliding to squeezing. Use smooth interior surfaces, gentle curves, and 1–2-stud-wide “lanes” to control single-file flow.

• Use “gravity + gate.” Pair a shallow chute with a Technic gate or axle-driven shutter that meters one piece per step. Add a rubber element only where needed for grip.

• Calibrate sensors in situ. If you use a color/light sensor, measure ambient light at runtime and set dynamic thresholds. Shield sensors from glare with a small hood.

• Gear for consistency. Choose slower, torquey gear ratios on metering components. Let conveyors run slightly faster than sorters to avoid backups.

• Add anti-jam escapes. Include bypass gaps, rounded corners, and tiny agitation cams (slowly oscillating beams) along chutes to nudge stuck pieces.

• Serviceability matters. Make hatches to clear jams, removable belts, and quick-release modules. Label input/output heights so reassembly keeps alignment.

• Close the loop thoughtfully. The return conveyor should merge gently into the sorter’s intake—ideally at a height and angle that minimizes bouncing and re-mixing.

• Balance queues. If the dispenser is your bottleneck, add an intermediate buffer (a mini holding bin) to decouple it from the sorter’s tempo.

• Log and iterate. If you’re programming the logic, record counts per minute and jam events. Small code tweaks (e.g., longer gate dwell) can transform reliability.

MOC Ideas Using the Same Factory Technique

• Micro Fulfillment Center: Pick-and-pack “orders” of colored studs into tiny boxes, then recycle any overflow back to stock.

• Airport Baggage Sorter: Luggage (2×2 bricks) routes by color/“destination,” with a return loop for missed bags.

• Coin/Token Sorter: Size-based sorting with inclined planes and slots, plus a recirculating coin elevator.

• Sushi Conveyor (Kaiten): Plates circulate endlessly; an order-picker diverts specific “dishes” to a table.

• Recycling Center Demo: Separate “materials” (tiles/rounds) by color/shape; compress into mini bales.

• Pixel Billboard: Sort colors into bins that feed a pixel-drawing head; misfeeds loop back for another pass.

• Candy Gashapon: Capsule loader that refills itself via a hidden return line behind the cabinet.

• Theme Park Mini-Ride: Omnidirectional belt “dark ride” that loops figures and props—perfect for show control practice.

• Quality-Control Line: Vision or light-gate rejects “defective” pieces onto a return path for rework.

• Educational Queueing Model: Show FIFO vs priority queues using colored candies as “jobs” moving through stations.

Factory MOCs like this are the ultimate proof that LEGO can be both playful and profoundly educational. By chaining Technic mechanics with sensor-driven logic, you learn real principles—flow control, feedback, throughput, and robustness—while building something everyone wants to watch (and taste). Whether you copy the full loop or start with a single metering gate, take the modular route, instrument your machine, and iterate toward that satisfying, jam-free rhythm. And if the candy disappears during testing… consider it part of the calibration.

Disclaimer: This article was created with the assistance of AI. While efforts have been made to ensure accuracy and originality, the content may include automatically generated text and should be considered as informational only.