7chains and pulleys

Transferring torque with LEGO pieces is possible not only with gears and axles but also with two additional systems: pulleys and chains. All of these systems work with similar principles.

LEGO pulleys are wheels that can be connected via strings or rubber bands, allowing for the transfer of drive and movement. You’ve seen similar pulleys in “belt” systems in real life. Pins without friction, bushes, and other circular elements can also be used as LEGO pulleys. A pulley system is particularly useful for lighter loads, transferring drive silently and over a long distance.

LEGO chains work similarly, though they’re better suited for higher torque than a pulley. A chain replaces the rubber band of a pulley system, and gears replace ...

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