MOC-4704 RC Crawler Material Handler Building Blocks

Take control of a compact tracked material handler with the MOC-4704 RC Crawler Material Handler Building Blocks. Designed and authorized by Nico71, this 874-piece model combines remote-control driving with a fully functional boom, extendable arm, automatically tilting grabber, and articulated tracked suspension.

Measuring approximately 33 × 18 × 18 cm, the finished machine brings together multiple mechanical systems in one engineering-focused build, allowing you to drive, lift, extend, and grab through independently powered functions.

Independent Dual-Track Drive

Each track is powered by its own XL motor, allowing the crawler to steer through differential track control and maneuver easily in tight spaces.

Double Bogie Track Suspension

Both tracks feature double bogie suspension, helping the crawler adapt to uneven surfaces while adding realistic movement to the tracked undercarriage.

Motorized Boom Raising

An M motor drives two linear actuators to raise and lower the main boom, recreating the lifting movement of a real material-handling machine.

Extendable Mechanical Boom

A separate motor drives the telescopic boom through a rack-and-worm mechanism, allowing the arm to extend and retract during operation.

Automatic Tilting Grabber

A sliding-gear mechanism automatically adjusts the angle of the claw as the boom moves, helping the grabber maintain a practical working orientation throughout its range of motion.

Motorized Claw with Clutch Protection

The grabber opens and closes through its own M motor, while a rubber-band clutch helps protect the mechanism when the claw reaches its movement limit or encounters resistance.

From the Designer

Nico71 developed MOC-4704 as a motorized crawler grabber inspired by the mechanical concept of the classic 8062 material handler. The design focuses on combining independent tracked drive, articulated suspension, boom lifting and extension, and an automatically tilting claw within a compact machine.

Particular attention was given to the linkage and gearing of the grabber so that several mechanical functions can operate together while remaining clearly visible to the builder.

A Functional Engineering Display

With 874 pieces and multiple remotely controlled mechanical functions, this crawler material handler offers an engaging building and operating experience for construction-equipment fans, tracked vehicle enthusiasts, and builders interested in gears, actuators, and mechanical transmission systems.