Lego City Set 60409 and 60420 Mobile Crane and Crawler Excavator (1749 pieces)

Lego City Construction Set 60409 and 60420 Mobile Crane and Crawler Excavator (1749 pieces)

Construction Node Equipment and Heavy Machinery Mechanics

The combined construction equipment set brings together two independent engineering machines for modeling the full cycle of loading, unloading, and earthmoving operations. The mobile crane is equipped with a multi-axle wheelbase and a complex multi-section telescopic boom, capable of extending to a significant height for vertical lifting of construction loads. The crane platform rotates fully around its axis, expanding the working area to 360 degrees. The crawler excavator complements the site with a massive bucket on a movable boom, which is driven by manual hinge joints simulating hydraulic pistons. The set includes builder minifigures with specialized work accessories, blueprints, and additional objects for transportation.

The functional features of the moving elements include the following engineering solutions:

• Four extendable side supports on the crane platform for stabilizing the position when working with the maximum boom extension.

• Integrated winch with manual tension mechanism, cable, and metallic hook.

• Crawler tracks of the excavator with deep tread for moving over uneven play surfaces.

• Opening control cabins with detailed interiors and seating for play figures.

The mechanical units of both machines operate without electronic components, relying solely on gear transmissions and axle connections. This allows for a clear understanding of basic physics laws, weight distribution of counterweights, and the principles of block lifting systems directly during assembly and play.

Integration of Construction Elements and System Compatibility of Components

The unified modular attachment system ensures a rigid fixation of all parts and high strength of finished structures under intensive play loads. Chassis elements, wheel axles, crawler tracks, and fastening pins are made according to the brand's single standard, allowing for the combination of special machinery units with each other. You can upgrade the crane boom, change the configuration of buckets, extend the wheelbase, or integrate parts into other large-scale engineering objects of the city series.

The process of interacting with the constructor elements includes the following construction stages:

• Connecting plastic blocks using stud fastenings, maintaining grip density during multiple assemblies.

• Using standard connecting beams for quick replacement of special machinery attachments.

• Using original helmets, radios, jackhammers, and wrenches of minifigures in all play locations.

The constructor serves as a basic platform for expanding the transport network of metropolises and is suitable for joint use with stationary objects, road plates, cargo terminals, and buildings under construction.

Technical Specifications

• Brand: LEGO

• Brand Registration Country: Denmark

• Product Group: Children's Constructors

• Purpose: Development of fine motor skills, spatial thinking, construction, modeling of construction processes

• Compatibility: Fully compatible with all elements, parts, wheel axles, and minifigures of LEGO City series and classic LEGO block sets

• Features: Extendable telescopic crane boom, 360-degree rotating platform, movable excavator bucket, functional winch, crawler track, extendable supports

• Gender: Unisex

• Age: 9

• Condition: New

• Contents: Plastic blocks for assembling a mobile crane, parts for assembling a crawler excavator, 7 builder minifigures, accessories, construction plan, hanging bio-toilet block, illustrated assembly guide

• Number of pieces: 1749 pcs.

• Number of minifigures: 7 pcs.

• Material: ABS plastic

• Size of the mobile crane with extended boom: 480x250x110 mm

• Weight: 2840 g