Unstepping Of Mast

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PeteD

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I need to unstep my mast this winter to replace the standing rigging. The Marina will supply a crane/driver only, with myself and a couple of helpers to provide the man power.
I have had many years exprience lowering/raising masts on my previous boats but the masts were all fitted in tabernackles. My current boat has a double sweptback spreader mast head rig (deck stepped). Is there anyone out there that could advise if the following de-stepping method sounds feasable.
Secure crane strop/lifting rope under the top spreaders; tension (with crane), remove forstay followed by shrouds and backstays(secure to mast base), raise mast (with crane) off it's mounting plate whilst manually stabalising/guiding off boat to ground.
Sorry it's long winded and possibly boring but any useful advise/comments/encouragement/discouragement would be greatly appreciated.
 
Pretty much how we've done it - however we attach strop under upper spreaders, then tighten a line from strop down to a cleat on mast so that weight is taken on line, and not loaded onto spreader base. Second thing is to have a pair of lines fastened to mast base, so helpers can control where it goes from a distance, rather than try to hold onto mast itself.
 
This reminded me when the yard provided the crane and driver to put themast of my boat in,the driver was late and Iwould have sworn he was at least I sheet to the wind.On reflection I wondered in the event of an accident,who would be responsible.
 
A seemingly minor but important point. Remove the forestay LAST and have a helper hold it under tension (pulling slightly forward) otherwise you run a real risk of the masthead clutter (Windex etc) being damaged by the crane lifting block or wires. It obviously helps if you (or another helper) move the foot of the mast aft gently as it clears the deck fitting/tabernacle.

Once clear of the boat, the forestay can be brought aft to lie alongside the stick.

I speak after snapping one of the vanes of my Windex/VHF aerial this year. The first damage sustained in over 30 years of dropping the stick every winter!! Doh!! /forums/images/graemlins/mad.gif I've seen it happen loads of times before too, so no excuse! /forums/images/graemlins/blush.gif

Agree with using a load carrying warp tied to the lifting strop and secured (we use the spinnaker pole attachment point on the mast) to a strong point. It may not be necessary, depending on the type of spreader attachment you have, but good practice anyway.

Aside from the above, you've got it spot on. My guess is you'll be amazed at just how simple and easy the whole operation turns out to be!! Never feels that way beforehand though!! /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif

Hope all goes well.
 
If there is any chance your mast may be top heavy secure the mast lifting strop with a masthead halyard. This should ensure a near vertical lift. Leave 4 to 6 feet slack in the halyard to save your masthead stuff. Dont rush it and make sure the crane has the load before undoing things!!!
 
Just to make it more complicated, what about a smaller yacht (eg. 23 footer) and no crane, but boat on cradle in yard, what's the best way then?
 
A month or so back, that was raised and one suggestion was using a timber 'A' frame, the apex a little higher than the spreaders with a block and tackle arrangement to lift the mast from its shoe and then lowering it to the deck. The link had photo's and diagrams and was being used on a Westerly Centaur. Similar arrangement would work for you.
 
Reminds me of when we first fitted a Furlex a few years ago. Strop around mast under spreaders, line from strop to mast foot, all the right things to do. Lift the mast (we were stepping it) and the whole thing went horizontal......

We'd forgotten about the additional weight of the furling system attached to the masthead - all rather embarrassing until someone else in the yard came to give a hand.

As an aside, if you've got fore & aft lowers or aft lowers & baby stay, the process is a lot quicker if you've already got the back, cap and forestays already off. Once the crane is ready to lift it's just a matter of undoing the lower 3 or 4. However, check with the crane driver/yard staff first.
 
Good idea before you attach crane is to slacken off the rigging as far as the bottle screws allow, and if possible remove the forestay and backstay and shrouds, or the lower babystay and lower stays.

The first makes it much easier to know when the crane is taking the strain, the second speeds up the actual removal of the mast.
 
[ QUOTE ]
Do you mean without a pivot bolt in a tabernacle? Just sat in a shoe?

[/ QUOTE ]

Just sat in a shoe, nothing fancy about this boat /forums/images/graemlins/wink.gif
 
Like me then.
I'll be interested to see the replies. We have a mast hoist at the slipway, which as a mooring holder I can use FOC, but being a council run thing you have to use their strops, wear hard hats and the warden has to operate the (manual) hoist. It's no bad thing as it's an extra pair of hands, but you can queue for it and feel the pressure of other mast-steppers waiting, so sorting out things like shroud lengths and rigging screws can be a bit rushed.

I used to use a derrick clamped to the pivot bolt and the forestay on my old boat.......... then run a line under the bow roller to the forestay/derrick to control the lowering process.
12mast%20being%20lowered.jpg


and thought I may make a clamp to go round the foot of the mast with a bracket to pivot on a bolt through the kicking strap lug on the mast shoe of my new(er) boat, enabling me to use the same technique.

maststep03.jpg
 
Can't find any refenence to this with the search, any more details? /forums/images/graemlins/confused.gif

[ QUOTE ]
A month or so back, that was raised and one suggestion was using a timber 'A' frame, the apex a little higher than the spreaders with a block and tackle arrangement to lift the mast from its shoe and then lowering it to the deck. The link had photo's and diagrams and was being used on a Westerly Centaur. Similar arrangement would work for you.

[/ QUOTE ]
 
Last Saturday had the fore & 2 backstays renewed on mine. Rigger did it by climbing the mast, supported by me on the main halyard as fall arrest. Took 10 minutes to disconnect, about 2 hours to make new (he drove back to workshop rather than bring workshop to marina) then about 15 minutes to refit. My mast has lower (baby) stays, but we used the jib halyard as standby forestay & topping lift as standby back stay. The spinny halyard was used to lower & lift the furlex & stays. Excellent job, cost was £270 squids and no trauma of mast tilting, getting crane back to restep, or restriction on sailing. This is a 26' sloop with a mast about 30'. Rigger also did an inspection on everything else up there. (mercifully found nothing amiss)
I did the lowers myself 2 years ago, but not brave or stupid enough to go right up so took this route & believe it is best way to go.
 
Plenty of good advice Pete. Agree with post that warned of top heavy mast...if greater portion is above spreaders then you risk an inversion so really important to control the foot...I have never tried the suggestion of using the main halyard to keep it vertical. At my club we have a mast crane with a hand winch, and I used it on my previous 44 ft mast for my Sigma. We always remove all the shrouds except the caps, then take the weight before removing these, then the fore and back stays.
 
Interesting suggestion....I have 4 shrouds on each side.I removed the lowers, babys etc first to avoid the strop pinching them as it sat under the spreaders. Took the strain, then caps then fore and aft. very straightforward.
 
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