DIY Liftout - Pointers please

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StevenJMorgan

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In the process of organising a lift out for the end of the month, have done this lots before but the only problem is this time due to my location this will be very much a DIY affair. Hopefully the crane driver will be experienced in lifting boats but here nothing is garaunteed.

Lift out involves craining out of boat from a berth about 15m from key wall, placing boat onto cradle on low loader then round to the boat park and craining off again onto hardstanding. Only have one cradle so second lift to hardstand will have to be done by tying cradle to boat some-how so pointers please on this. I also want to use spreaders to stop any crushing action on the hull so any advise on how to make these and how they should be used would be great.

So - to prevent further waffle, could use advice on

- How to make and use spreaders
- how many people and best format for lifting boat from dock to low loader
- How to lift boat and cradle from low loader to hardstanding
- Best way to remove mast from boat prior to lift
- how to best position slings on hull
- how to avoid damage to teak toe rail from slings

And of course any other useful tips -

thanks all.
 
If the crane is quite tall in relation to the beam of the boat, you can get away without using spreaders. If spreaders are necessary you may have problems working on a DIY basis because they span between the crane hook and the top of the lifting slings, usually made of chain kept apart by a length of box-section. As such they take the full weight of the boat, and therefore have to be tested and inspected every year by the insurers of the crane. If you knock up a set yourself, you may find that the crane driver will refuse to use them for this reason. I would contact the crane company and see if they have something 'legal' and suitable.

As for the lift itself, obviously your main concern is to avoid lifting on your propellor shafting etc. If she is a modern paper-dart-shaped boat she will lift with the bow well down due to the aft-most sling having to go round more boat than the front. This may cause problems with your plan to juggle the cradle and boat together. I sometimes add in a short sling to the aft one to compensate for this factor.

For getting the mast out, a well put together aluminium mast can be lifted by means of a short strop under the spreaders. If you are in doubt as to the spreaders taking the load, run a preventer line bowlined on to the strop and made off on cleats or round the winches at the bottom.

Without actual sizes I can't be more specific. pm me and I might be able to email you some relevant pics. Good luck and I hope you get her back in before the summer is gone.

Mick
 
15m from the quay wall is quite a reach. With the crane outriggers on the edge of the quay wall you will be looking at a lifting radius of 20m from the crane pivot. I don’t know the weight of your boat (you will have to find this weight to a reasonable standard of accuracy) but to lift 8 tonnes at 20m radius you will be looking at a 90 - 100 tonne capacity mobile crane. And that 8 tonnes would have to include the spreaders, slings, and crane hook block. Make sure the crane supplier knows about this radius or he might turn up with too small a crane. Also the outrigger loads on the quay wall could be 30 tonnes or more so somebody should check that the wall can take this.

Spreaders for lifting boats in the UK are usually welded steel frames. They would be classed as part of the lifting gear here and have to be tested, certified and regularly inspected. Home made spreaders would be unacceptable. Things are probably a bit more relaxed in the Gulf; but failure of spreaders can put shock loads on the crane and cause it to overturn if it’s working near its limit. Not to mention possible damage to the boat from a less catastrophic failure. The longer the slings from the spreader to the crane hook the smaller the load on the spreader because the angle of the slings to the vertical is smaller with long slings. A 90 tonne telescopic mobile is likely to come with 40m of boom so there will be plenty of room under the hook for long slings.

Slings need to be carefully positioned to avoid the keel and propeller shaft or saildrive leg. Do you know the underwater shape of the boat?

You will need two lines attached to the bow and stern and long enough for two people standing on the quay wall to hold the ends of these lines to control the rotation of the boat as it is lifted.

I’m not sure about lifting the boat with the cradle hanging underneath it. Is the cradle rigid enough for this? You will also have to find fixing points on the boat strong enough to support the weight of the cradle. The weight of the cradle will have to be added to the weight of the boat and lifting gear for the second lift but presumably you can arrange this to be at a smaller radius. Can you put the boat down and temporarily chock it with timber props while you move the cradle?

All the above is based on my experience of construction cranes. I’m not experienced in lifting boats. But at least you have a couple of weeks to get things sorted out; it’s not something that I would like to rush in to. In the UK most of the big crane hire outfits would give you a quote for contract lift for this sort of operation. For a fixed price they would provide the crane and all the required lifting gear and labour. But things are probably different where you are.

Good luck!
 
I am responsible for crane in and crane out operations at our sailing club. I recently attended a week long Appointed Persons course to qualify me to continue doing this.

First, I assume that this lift is taking place in the UAE, and not in the UK. If its in the UK, ask the crane operator for a contract lift - these issues then become his problem.

Don't know what regulations (if any) apply in the UAE. Assuming none:

Are you happy with the condition of the crane?
Are you confident that the ground on which it is to stand won't give way under the load?
Do you know the actual displacement of your boat (manufacturers figure, plus all the gear you have aboard)?
Can you obtain copies of the duty charts (also known as SWL charts) for the crane? If you can, check that the crane is rated to lift your boat at the expected radius.
Look for slinging point marks on the toerail. If none, one sling forward of the keel, and clear of any log impellor, one sling aft clear of the propellor & shaft.
You will need two people to handle tag lines fore & aft (use the mooring lines if they are long enough).
To lift a cradle with a boat, you need two of the ratchet tie down straps used on lorries. Use these to attach the cradle to the boat, and then lift the boat using slings around the boat's hull as normal.

Make sure everyone involved knows who is in charge, and instruct the crane driver to accept instructions from that person only.
Discuss what signals you are going to use with the crane driver beforehand.
Take it slowly, and if you are unsure about anything, stop & sort it out before continuing.

Good luck
 
If this was in the UK the spreader bars would be subjected to the same statutory inspections and insurance as the rest of the lifting gear.
The crane operator who comes to the yard where I am based avoids the need for them by having long slings on "four brothers" (chains) but when one owner insisted on them they had to be hired in specially, they were only used for his boat and he had to pay for them. Even he does not ask for them now!

Not too many helpers who don't know what they are doing. Two in addition to the crane drivers mate may be enough. Hard hats and steel toe caps all round, good tough gloves as well. I know a hard hat won't save you if the boat falls on you but that spanner you forgot to pick up off the deck will kill you if it falls on your head!

Position of slings depends entirely on the hull shape etc Since we are always lifting from a drying pool we always put some bits of old rope around beforehand so that we can pull the slings round where the they need to go. You are not using rope slings are you?

The slings should not damage the toe rail but some old carpet will protect them if necessary, and the rubbing strake. More at risk are stanchions and guard rails.. It's not a bad idea to remove them competely before hand.

Maybe the crane can lift the mast but it will be difficult to bring it ashore if not alongside the quay. Perhaps you can have some supports ready on board so that it can be lowered onto those AND SECURED or then reslung and lifted ashore.

Do not know about lifting boat and cradle ... never seen it done!

Have a long warp on both bow and stern to guide the boat while it is in the air.

15 m from the quay is a long way. It will need a crane with a very high lifting capacity compared with the weight of the boat to do it . We lift very small boats from quite large distances away sometimes but the bigger boats are always alongside.

Hope these comments help. I am not qualified in any way but I have helped out on craning day at the yard many times, even though my boat comes ashore on a trolley, so I am beginning to know the ropes. (deliberate pun!)
 
Didn't see DJEs post until I posted mine - we seem to be saying the same things though.

Just checked - the Malo 36 displaces 6100kg. To that you will have to add maybe 3/4 tonne for gear on board, another 5-600kg for the crane hook block, plus maybe another 250 - 500kg for spreader bars & slings. So 8 tonnes seems a reasonable figure for the lift, for a Malo. Biggest crane for which I have duty charts to hand is a Demag 60 tonne. It won't cope with the job, so you are probably loking at an 80 - 100 tonne capacity crane, for a Malo. The Najads tend to be heavier though, so an accurate figure for displacement is important.
 
Leibherr 90 tonne mobile duty chart here.
If you can get the crane back on to the quay wall you can probably get the radius down to 17 or 18m but I wouldn't push it too hard. Better to have a bit of capacity in hand.
 
All of the above is good. We lifted boat and cradle from hard standing to wagon and back again although check that the cradle is still properly aligned before lowering all the boat's weight onto again. 15m is too far for anything but a large mobile crane and would be unecessarily expensive.

We loosely lashed the slings onto to the toe rail to prevent them slipping too far, but the lashings should remain slack for the lift. Trial lift the boat and adjust the sling positions as required. Oh, and no one should remain on the boat during the lift.
 
My last boat ( a Dufour 35) had lifting point in the bilges for hoisting the boat on a single cable. The full instructions for doing so were in the owners manual.

Certainly might be worth your while having a look in the bilges.

As for the cradle, the yard my boat is in at the moment all the boats are supported on lengths wooden logs about 5 feet long with soft wood wedges.

Be carefull with the whole affair I have seen huge cranes tipping with relativly light loads over long reaches..
best of luck.
 
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