Parking Cranes in Weather Vane Mode

One of the local construction sites set up this self erecting tower when they had easy access to the center of the building.

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It is electrically powered and controlled by remote control. So you are renting just a trailer, not a truck, diesel engines, and a cab.

The above photo after it was cropped

Each day the boom would be facing a different direction, so that allows me to get several different angles of the base from the one area where they have not yet built a wall so that construction equipment can drive into the building area.

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This video records the rotation speed. It was getting close to quitting time and they just rotated it over 360 degrees with no load.
(full window)

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The next day was the first time I saw them actually use the crane. Here they are adding posts to the edge of the east wall. Earlier, when they were working on the north wall and I first took pictures of them, they came over and talked to me because I had a camera. I find this common and to my benefit because it gives me a chance to ask questions. The crane was installed mainly to lift the wood panel walls when they get that far into construction. It can lift four tons by the tower and one ton at the tip of the boom. Those posts were certainly less than a ton! I'm glad you can't recognize the faces because inside the fence is supposed to be a hard-hat zone. When I mentioned that every time my wife or I go to the library, we noticed the boom was pointed in a different direction. We thought that was because they had done some work that day and we missed it. He explained it could be because they park it in "weather vane" mode. That is, the boom turns rather than create a lateral force on the tower if there is a crosswind. He said the wires going up the tower will tolerate three revolutions. I confirmed that the reason the turned it at the end of the previous day with no load was to remove the twist from the wires so that it could do a full three revolutions in either direction while it was unattended.

The photos that were here of a Bucyrus-Erie 1360W have been moved to the coal mine in which it is parked. That dragline was parked with its boom facing West. Then a strong storm turned the boom towards the North. The boom has been rotated back to facing West.