lifting boat out of water

gonad

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no uhauls here could i use a large crane put one strop round front of the mast and one under the cockpit or might that just crush the sides in want to do it with mast up thank jon
 

William_H

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Any good crane operator should carry spreader bars which spread the webbing slings just above the deck. Without these you risk crushing the hull sideways. He will need 2 slings one forward and one aft. These may also need a spreader from one sling to the other depending on the height from the deck to the point where the 2 slings meet. He will then have to lift the boat a little to get the balance correct by moving the slings forward or aft. I think he should be able to work around the mast.
I have been involved wwith one operator here who lifted a 24ft boat. He knew what he was doing and there was no fuss or problem.
good luck olewill
 

charles_reed

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Crane-lift is probably the most common method of lifting boats out of the water, outside of marinas.
Though I have had my boats more frequently lifted by crane than travelift, I would probably refuse a lift in the manner described by WilliamH.
To avoid having to take backstays etc off the boat the crane hook needs to be about mast height, the strops go round the hull, one set @ about the level of the cockpit sheet winches, the others to balance the boat.
Spreaders are desirable, for monohulls, and essential for multihulls. Frequently this is a fabricated rectangle but I have seen a single boom used.
These dimensions demand the use of a fairly large crane, operating well within its load limits.
It's much slower than a Travelift, needs about twice the personnel and, unless boats are being deposited close to the exit point, requires a parking trailer. It demands far lower capital investment and, used in conjunction with a boat trailer, allows about 30% more boats to be packed into the stand. The majority of big boatyards use a Travelift in conjunction with a trailer.
The largest boat I've seen crane-lifted was a 84' long caique by a fixed dock crane.
 
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Tranona

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You need to find a crane operator who is familiar with lifting boats. With the proper equipment it is an easy job. As already suggested, it needs a jib that will get high enough not to need spreaders if you want to do it with the mast up. Provided the strops are long enough spreaders are not needed - and with some hull forms can actually be bad. There is little danger of crushing the hull if they are properly placed. They should be placed at the position of the main bulkheads. Make sure the crane is big enough. The yard I use lifts boats up to about 45ft and uses a 25ton mobile crane.
 

oldharry

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As has been said, using a mobile crane tp lift boats is very common. An operator experienced at lifting boats is important, as he will know safe spacing of the two strops as per the pic above: on a more curved hull there is a risk that the strop can slip out with dramatic and unexpected results! You also need to be sure the strops do not foul any hull fittings like log transducer paddle wheels. Our yard regularly lifts boats with the mast up, but the crane operator needs to know beforehand so that he has long lifting chains chains to clear the mast and rigging (see the chains in Fantasie 19's pic - they need to be about twice the length relative to the size of boat. The longer chains also reduce the crushing pressure on the hull as the strops lead out nearer vertical. If a spreader frame is used, it will be quite difficult to work round the mast and rig, particularly on a bigger boat.
 

ianat182

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Some thing that is often forgotten by first-timers is to slacken the lifelines(and remembering they are slack when getting aboard again!) this will help prevent bent stanchions during the lift-in and lift-out.

ianat182
 

VicS

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As has been said, using a mobile crane tp lift boats is very common. An operator experienced at lifting boats is important, as he will know safe spacing of the two strops as per the pic above: on a more curved hull there is a risk that the strop can slip out with dramatic and unexpected results! You also need to be sure the strops do not foul any hull fittings like log transducer paddle wheels. Our yard regularly lifts boats with the mast up, but the crane operator needs to know beforehand so that he has long lifting chains chains to clear the mast and rigging (see the chains in Fantasie 19's pic - they need to be about twice the length relative to the size of boat. The longer chains also reduce the crushing pressure on the hull as the strops lead out nearer vertical. If a spreader frame is used, it will be quite difficult to work round the mast and rig, particularly on a bigger boat.

Long chains like this.

DSCF0314.jpg
 
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