Sariel.pl

My third Monorail ceation, features a single loop with two Monorails, a cargo truck and a gauntry.  

Datasheet:

Completion date: 21/05/2011
Power: electric (Power Functions) / 9V (Monorail)

I have a soft spot for unusual machinery, and gauntries, with their distinctive construction and obviously huge fun factor, are exactly such a thing to me. I have already built one simple gauntry back in 2008, and this time I wanted to try to re-approach the subject using the Monorail system.

I started by looking at old Lego harbour cranes sets which used to fascinate me when I was a kid, and it prompted me to buy special Lego supports for cranes. With these at hand, I have built a single, long gauntry with a bogie housing two 71427 motors: one driving the bogie, another one driving a winch (both with safety clutches). Attached to the winch was a simple custom hook that was supposed to lift and carry three identical containers weighing 73 grams each. I have created two Monorails with rear cars serving as container platforms and with front cars occupied by the drivers and battery boxes. To let two Monorails use a single track, a fork was created using two track points. The Monorails were controlled with monoswitches, so they always stopped exactly in the same place. This, and the fact that the gauntry was stretched a lot and already facing problems with structural rigidity, made me decide to make the gauntry fixed, unlike the real gauntries which can move forth and back using special, usually short tracks.

The two Monorails have been completed by a cargo truck. As the Monorails were 4 studs wide, I was determined to keep the truck 4 studs wide too, while making it remotely driven and steered. It was achieved by using two motors: a 71427 motor for drive and a micromotor for steering. The 71427 motor was driving a single wheel hidden under the trailer, and the micromotor was geared down 3:1 and was rotating the whole tractor unit against the trailer. As a result, the truck could drive and steer successfully over a perfectly flat surface, despite the fact that it had no steered wheels and that none of its visible wheels was driven. Additionally, the tractor unit housed working headlights.

While the truck was remote controlled, and the Monorails were controlled by monoswitches, the gauntry itself was controlled by two switches located on its side. I have used the old 9V switches and the old 9V wires, because they were thinner and not as stiff as the Power Functions wires. The gauntry also had over 10 pairs of Lego LEDs installed on it, which resulted in a massive amount of wires.

The whole construction worked reasonably well, except that it was difficult to catch a container with the hook, and that the hook had a tendency to rotate left or right sometimes. This part of the gauntry was clearly underdeveloped. It was only after this construction was finished that I learned about the Lego crane grabber piece, which would solve these problems easily. This piece is so interesting that I’m planning to build another gauntry just to put it to use.

Note that this whole construction used no PF motors whatsoever. Each Monorail was driven by a Monorail motor, the gauntry used two 71427 motors, and the truck used one 71427 motor and a micromotor. The Power Functions system was used only to power the gauntry and its lights, as well as to power and control the truck.

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