dimnix86's Lego Technic Liebherr 9250 Excavator

[DLuders]

dimnix86/ NaturalBornUser posted this

of his Liebherr 9250 Excavator model using Lego Technic elements. On his website (in Polish and in English), he wrote (in this rough translation),

"I present a model Liebherr 9250, the largest of the excavators...The original weight exceeds 250 tons, the engine power is more than 1000 hp, and the bucket capacity is 15 cubic meters (about 27 tons of rock and earth) indicate that we deal with a serious machine":

"Pf [Power Functions] XL {motor] drives both tracks, with the possibility of a seven-speed adjustment via remote control. Pf Medium [motor] is used to turn moving to the front of the vehicle while speeding up the one and releasing the second caterpillar to a degree dependent on the remote control. Thus, the higher the twist the steering wheel on the remote control, the smaller vehicle's turning radius makes steering very convenient....Running the Medium [motor] during the stationary-off XL provides turn in place by the movement of one track to the front and one back with the same speed. So much for the advantages of a subtractor."

The model's specifications:

* Weight of Base = 1100 grams

* Rotating Cab Tower Section = 2300 grams without arm

* Upper Arm = 900 grams

* One caterpillar tread consists of 42 Technic Tread pieces.

* Inside the tower there are 3 motors:

- Pf XL Motor - to raise the whole arm

- Pf Medium - Tower Cab rotation

- Pf Medium - bending the arm in the middle

There is a good description of the wire-activated Linear Actuators that he used -- check it out on his website links above.

[garson]

i would think using string to lift those loads would break it and also how does he lower the arm does it just fall by weight?