Howto un/step keel-stepped mast without crane ?

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Boo2

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Hi,

Is there a way to un/step a keel stepped mast on a 35 foot sloop without the use of a crane ? (Note : please take this as a given, not a debating point - I would surely use a crane if I could, I'm not completely daft.)

The mast is fitted fairly normally, including spinnaker gear, but there are no special tools or fittings available (though they could be bought if required).

Websites with detailed descriptions and pictures, book references or forum links are all welcome.

Thanks,

Boo2
 
I've seen it done with the boat in question moored between 2 others, each on a pontoon and using their main halliards, and several bodies. The lifting strop at the spreaders.
A bit fraught though, IMHO!
Edit:- Even more fraught for a twin spreader set-up!!
 
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Moor between two other boats and tie their halyards to your mast.

A friend was a flotilla skipper and this is what they did with their fleet at the begining of the season. Admittedly, they did it with deck stepped masts, but the principle is the same.
 
My mast is keel stepped, it is difficult enough with a tall crane. Lifting in is trickier than taking out (just did it yesterday)Taking account of the replacement cost, there is no other way I would try it. However the jib on most travel hoists can also cope at low tide. They dont need the same clearance over as they dont use a big hook swinging about, so only have to reach the top spreaders (Airdraught about 15m. plus 2m. below deck)
Keel stepped masts are much better than deck stepped, the handling issue is the only downside.
 
I think the advice from Sighmoon and Earlybird is crazy, the risk is considerable and no insurer would cover it. I dont think either could have tried to guide a foot on to an keel step, you need a very stable controllable arrangement or you could lose a hand or just a few fingers. I have stepped about 15 times on two different boats, this year because it was windy I now have to go to the top of the mast to straighten the Windex.
 
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The method suggested by Sighmoon & Earlybird is just fine. In the the Merchant Navy (when we had one) this was known as a Union Purchase, albeit rigged from derricks.

The two partner boats will need, ideally, taller masts than your own to deal with the additional 7' of draw needed to get the heel of your mast out through the partners.

Gear will need to be good and well sized as the two halyards will form a "Y" shape at the becket where it girdles your mast. The wider the "y" the more the load on the lines will increase exponentially, hence the taller the masts the better.

Simple, safe & easily controlled procedure which has worked well for many many years.
 
Still waiting to hear from some one who has done it with a 16m+ mast with two yachts. I have used all sorts of jibs to put up smaller deck stepped masts (Sigma 33 OOD) but lining up through the deck collar and on to the step requires more precision and stability than you could manage this way. Charter companies and the Navy may have cover but I don't think many yacht owners could insure it. The derrick arrangement would be well over its limit with the mast the OP is referring to. It is not good to advise a beginner that he could easily do something that you have never done yourself, he could buy the boat on the strength of the advice. No matter how old the mast is, a replacement will be new and very expensive when you have to pay for it yourself, and it will still need to be stepped.
 
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Quandary said:
I think the advice from Sighmoon and Earlybird is crazy, .
Click to expand...

Except that I've seen and assisted in just such an operation on some-one else's 30 ft. boat. My own mast is keel-stepped and also heavy, so I do know about lifting and re-stepping. I personally don't particularly recommend the method, but it is possible.
A club that I know regularly handle two dozen or more deck stepped masts in a day, twice a year, by this method, but that is a more straightforward operation.
 
earlybird said:
Except that I've seen and assisted in just such an operation on some-one else's 30 ft. boat. My own mast is keel-stepped and also heavy, so I do know about lifting and re-stepping. I personally don't particularly recommend the method, but it is possible.
A club that I know regularly handle two dozen or more deck stepped masts in a day, twice a year, by this method, but that is a more straightforward operation.
Click to expand...

I am genuinely interested in that, can you tell me a bit more? which club? how many of the masts are keel stepped and what type of yachts are used to do the lift. Also does the club provide the insurance for the operation or can the individual owners get an extension to cover it.
I spend £400 on every lift out/in including unstepping and stepping, organized by the local boat yard and covered by their insurance. The crane has to make a 6 hour journey each way because the local cranes are not tall enough which makes up a lot of the cost. However I might have difficulty finding two willing owners with stable enough boats with tall enough masts. It would be much cheaper to use a marina travel hoist but then I would have to go a considerable distance and pay for the winter storage.
 
Scaffolding and Chainhoists

If your boat is ashore erecting scaffolding around it may give you the platform and structure needed to lift it and rotate the mast horizontally. Even if it's along side a quay or shallow water you could erect a structure, then with chain hoists lift the mast up and out. Fraught with hazards which would need careful planning to avoid.

You could erect the very straight forward tower systems, one on each side then span between them beside the mast and lift. An 8 m tower is about £75 - 150 a week to hire. They are very common and you might be able to get loaned a set for free if you ask around.
 
More negative response from me. The boat is 35' the mast will be at least 15-16m long (the mast on my 33' boat is 15m. plus appendages) and will need to be vertical above the step until through the deck so tower pivot will need to be more than 12m from deck plus 4m to ground say 16m. (Think 6 storey building) Even you erected such a structure putting the mast back up there to restep would be some fun. No offence, I know you are trying to help but I think we are getting close to fantasy
Wonder why so many people use cranes?
I am amazed to be the only one who sees serious risk in encouraging these methods.
BTW. I don't think Boo has bought a boat yet, so this may be a theoretical exercise.
 
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My sailing club (Carrickfergus) had a static lattice jib crane beside the slip with about a 12m jib. it could handle big loads and masts up to about 40'. only a select small group of members were allowed to operate, it but in the end it became impossible to insure and certify it so it had to go for scrap.It could not have coped with the mast the OP refers to though because of the problem of elevation needed to get a true vertical feed through the deck ring and on to the step car.
 
It only needs to be 8 m tall one each side with a beam between (yes 8 m may be too small once the mast is out but he can work out the height) Top of mast is stayed 4 ways. The fore and aft stays are used to pivot the mast and the boom is used to lower it vertical.

I know this works and have used many staid towers to handle 40' joints of 5" steel pipe from horizontal to vertical and vice versa when running them into a hole on low cost water well work overs. I also raise and lower drilling derrick masts at over 147' tall using stays and simple "A" frame.

Its not fantasy, its facts. It needs thought through and planned but is very easy to do and has been done, probably for many thousands of years, on many structures. The methods are simple and the standard 8 m scaffold tower is probably more than adequate to provide the structure height.

Its an option he can consider.
 
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I have a compass derrick, and it handles the relatively small mast ( 9m deck stepped) on my Dehler easily, but even so its not what I would call a painless exercise, probably as I don't lower the mast much (did it 3 weeks ago)

It may be too obvious a suggestion, but why not contact a few riggers for advice. Its not a job I'd want to do for the first time without at least some well experienced person on hand. Once you've seen it done and helped its so much easier to contemplate the job on other occasions.

Tim
 
Right Boots, you reckon a few amateurs with ropes will be safe lifting a 15m mast using an 8m. tower? When it clears the deck 11m of it will be above the support structure and have to be lowered safely with guys, when it gets down to about 20 degrees above horizontal the moment of the rig weight (say about 200kg.) on that lever will be what? You dont need to put much of a kink in an alloy mast to make it useless. Are you absolutely sure you don't have powered winches and trained operators when you handle your long pipe sections?
Don't get me wrong, I am content it can be done, but not by a guy who has never owned a boat working in the confines of a boatyard or on the water. Having once dropped a much shorter mast, only about 11m. and deck stepped (fortunately into deep water) I still recall the amazing increase in force on the guy ropes as the thing went down.
The OP should not be put off by the mast being keel stepped, nearly any boatyard will have gear that can handle it and it will not cost any more than deck stepped, but he should not contemplate trying to step and unstep it himself, the risk of injury and damage is just too great.
 
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