How to de-rig a mast??

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adamgodfrey

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I am having difficulty finding a rigger to derig a boat that I am hoping to have transported by road next week. A crane is available to remove the mast. Can anyone advise how easy it is to derig the boat ourselves?
She is a 30 ft yacht. Is it a case of removing the boom, and genoa. Then loosening the stays etc, disconnecting the electrics at the foot of the mast, and having the mast lowered by crane.
Can anyone advise how possible this should be for me and my father to do?
Thanks
Adam
 
should be a piece of cake, just as you have outlined. The yard which cranes the mast should also help you undo the stays etc, but it helps reduce costs if everything is ready first, with mousing wire and tapes undone etc. If removing all the rigging from the mast, good idea to label everything to assist replacement - also suggest taking plenty of photos to remind yourself what goes where when you re-rig.
 
very easy, providing you do it logically and carefully.
You dont say whether the mast is deck stepped or through hull, as that will make a difference about how well supported the mast needs to be.

remove all the sails, and remove boom the day before (or earlier)

disconnect all the electrics - preferaably well before the day itself, as sometimes this needs a lot more than expected. I tend to put the plugs into plastic bags and seal them up.

On the day - use topping lift and main halyard as temporary 3/4 side stays (i.e. half way between the shrouds and the back stay). use the genoa halyard as a temporary forestay. With these 3 tensioned they will happily support the mast while you remove the standing rigging, and will be much faster to remove when the crane is ready to lift.

get crane driver to tell you where to sling the mast , and let him take all the slack out of the crane line, so that when you release the halyards, the mast will be happily supported. when crane driver is ready, release the bottom bolt holding mast into position (or whatever system you have).

get crane driver to lay mast on ground and remove all standing rigging , and any instruments and lights that are designed to be removed.

move mast to transport

go to pub /forums/images/graemlins/smirk.gif /forums/images/graemlins/smirk.gif /forums/images/graemlins/smirk.gif
 
Usually it is quite easy. Stays are normally connected to the mast using clevis pins. You only need to remove the split pins and knock/push out the clevis pins. Shrouds may be attached with clevis pins or with T-balls, which simply rotate and come out.

Electrical disconnection may need some thinking about beforehand, dependent upon the existing connectors. If you have plugs on deck then no problem. If you have unbroken cables right through I suggest you prepare for removal by cutting below deck, then having suitable male/female joints for use when you re-step.

I have never bothered to remove any rigging in these circumstances, unless the mast is being taken separate from the boat. Just tie all rigging to the mast with lengths of line, bungee or whatever you have handy. Something like this.
IMG_2056.jpg
 
I dont think you need the mast lowered by a crane, I can drop the mast on my 23fter on my own. A couple or three of you should do fine.

Two at the base of the mast, one holding an extra long halyard who walks towards the mast as it goes down. Make sure the two people at the bottom walk towards the end (top) of the mast as it gets to abot 45degrees.

You might be wise to get a couple of larger mates to help to be on the safe side, but Ive got a pretty big mast on mine, and i can do it fine (although with a bit of effort!) on my tod.
 
Depends on the design, but there's a world of difference in section, weight and length between a 23 footer and a 30 footer. Years ago two of us struggled to carry the mast of our GK29 a short distance. I wouldn't like to try it with 10 people helping, even assuming the foot to be pinned in some way, unless it was set up for it with shroud and mast pivot points on the same line.
 
In addition to all the other excellent suggestions, I would recommend 'freeing' all the bottlescrews well in advance; just to make sure they turn.

The craneage is charged by the hour (or minute or second or...), so you don't want to find they've siezed up at that point.
 
[ QUOTE ]


I dont think you need the mast lowered by a crane, I can drop the mast on my 23fter on my own. A couple or three of you should do fine.

Two at the base of the mast, one holding an extra long halyard who walks towards the mast as it goes down. Make sure the two people at the bottom walk towards the end (top) of the mast as it gets to abot 45degrees.

You might be wise to get a couple of larger mates to help to be on the safe side, but Ive got a pretty big mast on mine, and i can do it fine (although with a bit of effort!) on my tod.

[/ QUOTE ]There is NO WAY I would countenance dropping the mast of an average 30 fotter in this way. Rigs go up in weight and size and become exponentially more difficult to step and unstep by hand.

For example the mast on a 55 footer that I used to sail a lot weighed over half a tonne.

My mast on my 39 footer can just be lifted by three hefty men.

OK so 30 foot will be proportionally less - but NO WAY should you try lowering it in the way described. Once you realise you can't manage to hold it - it will be TOO LATE....

You might manage with a 'gin pole arrangement' - I have seen a 50 foot radio mast put up single handed with a gin pole, but the easy option is a crane.
 
falling masts

Falling mast can do a great deal of damage even for a 20 foot boat. One problem is that the lowering gets more difficult as the mast gets away from vertical and can surprise you - lethally!
The anodised finish is surprisingly fragile. Mine has suffered somewhat with annual raising and lowering. Padding places where it will contact other objects is a very good idea.
 
I used to happily drop the mast on my previous two boats (20 and 22 ft ) single handed, but that was with a well sorted out, evolved, system which ultimately involved an A frame. Crucially, both masts were also mounted in tabernacles.

My current 30 ft boat does not have a tabernacle. I would not contemplate trying to lower its mast without using a crane. I can think of no system for doing so safely.
 
One poiint to watch.

Make sure the crane's strop goes far enough up the mast (till stopped by spreaders) to be above the point of balance. Our club lift 40 masts each April & October, and it only gets exciting when a mast is top heavy (and we don't know that in advance). If the mast is lifted below the balance point, it will suddenly do an invert which can be very nasty for anyone in the way.

Must say most masts seem to have spreaders well above half way, but take account of heavy gear like radar scanners.

Have fun, it's well possible to DIY if you take advice already given.

And as someone said take pix and make lists. Itr will look like a tangle of meaningless wire & rope when you come to put it back up...

Chris
 
Re: falling masts

As mentioned by an earlier contributor, I strongly recommend photographing everything with a digital camera so you know exactly how to reconnect. Particualrly useful for things like the electrical wiring. When the mast is down also photograph the masthead fittings - in case you ever need to fix anything up there, can get the right parts.
Also ideally mark the bottlescrew tensions to save time restepping.
Having done this, everything is a doddle - provided you get the profesional crane lift.
Good luck
 
Re: falling masts

Yes a 30ft mast is a formidable weight for DIY lowering. If you got organised and had a deck stepped pivotting tabernacle you can lower it to near horozontal for bridges etc.
However the removal of the mast from the swing tabernacle is the really hard (heavy) as the A frame usually balances the mast such that it is top heavy with more mast sticking out over the transom.
The only way to manage then is to have several helpers lift the top of the mast from a jetty with the boat suitably positioned.

So yes get a crane. good luck olewill
 
Re: falling masts

Having done this twice in the last month I feel compelled to post on this one.

First of all...

1. If you do it wrong its easy to kill someone.

2. If you do it right its easy.

As some stated here (and sailing in general really) the key to it is preparation and planning.

I wouldn't even think about dropping it manually but have done it with a gin pole and the mainsheet. This worked great but would have been better with the boat aground (bilge keeler) due to the boat movement as people moved around on it.

If using a crane (AKA the clubs bodged up derrick on a pile), make sure it has the required range of movement, dont get stuck with no rope left and the mast still 3 ft above the pontoon.

Using the running rigging as temporary stays is a great idea, wish I'd thought of that :-S

Have spare clevis pins, at least one is bound to end up overboard!

Plan to replace everything at the masthead when it's down, a good chandlers will let you return stuff you dont use.

Call in family and friends to help (cheers Dad/ultramarini!), many hands make light work and they may help in thinking 'out of the box'.

Hope this helps

Tony S (the other one)
 
Re: falling masts

[ QUOTE ]
Yes a 30ft mast is a formidable weight for DIY lowering. If you got organised and had a deck stepped pivotting tabernacle you can lower it to near horozontal for bridges etc.
However the removal of the mast from the swing tabernacle is the really hard (heavy) as the A frame usually balances the mast such that it is top heavy with more mast sticking out over the transom.
The only way to manage then is to have several helpers lift the top of the mast from a jetty with the boat suitably positioned.

So yes get a crane. good luck olewill

[/ QUOTE ]

Dont like to disagree Olewill, but 2 of us can drop my 32 foot mast whenever necessary without problems. Putting it back up is easier with 3.

Lowering: Long (20m + ) line to the jib halliard, bloke on the end to control rate of descent. Much easier if he is on a dock and higher than deck level.. Bloke 2 on the deck guides the mast down into the scissors.

Erecting is the reverse, but is easier with 2 blokes on deck to steady and lift the mast through the first 20 - 30 degrees.

This all assumes the mast is tabernacle mounted. If its not, use a crane. Any other mast heel fitting will break if its allowed to twist. If no crane is available then at least 4 people on deck to control the spar and keep it in line.

We have not experienced the problem you mention of releasing the heel from the tabernacle either, unless the mast is mounted further aft than usual, and the scissors are too far forward from the point of balance. If that happens then I agree, you do have a problem needing a lot more manpower.

The key to the whole thing seems to be to have the scissors arranged so that when the mast is down it is at least 10 - 15 degrees angle to horizontal. It suddenly gets very difficult if the guy on the headline can not take the load because of the angle.
We do it quite regularly on boats up to around 28 ft length.
 
Lots of useful suggestions here but I would definitely use a crane for your size of mast.

Having helped to remove and replace many masts on club members' yachts over the years, this is what I would do. I have assumed you have already removed the boom and sails.

1. Tie off all the ropes (halyards, topping lift) onto the mast along with all loose electric/VHF etc cables. If these are tied neatly and tightly against the mast in a couple of places it keeps them well out of the way. This can be done the day before.
2. Before the crane arrives remove all lower shrouds and baby stay (if you have one) from the deck. Tie off these against the mast with some more short lengths of rope. Using different ties from the cables and ropes helps keep everything organised when you come to refitting. This leaves just the backstay, forestay and cap shrouds
3. Loosen the rigging screws enough so the clevis pins in the remaining rigging are loose on the deck fittings. If you don’t have the open style of rigging screw, be careful you don’t unscrew them completely off! If you are unsure, back it up with a halyard until you know how far to undo them. Straighten the split pins in the clevis pins so they can be quickly removed but not so straight they fall out. Loosen any bolt at the mast base but leave in place.
4. You need to lift the mast with a length of rope which will match the distance from your spreader to a couple of feet above the top of your mast (aerial and wind vane). Tie a very large bowline around the mast with the knot aft and tie another loop in the rope to match the distance I have just mentioned. When the mast is lifted, you want the very heavy hook and block of the crane above and just behind your mast not banging into it.
5. The top loop of the rope is put in the crane hook and as the hook rises, the lower loop should rise up to the spreaders. It can be useful to have another line tied to this lower loop to allow you to flick it over any obstructions as it slides up the mast. Sod’s Law dictates it will catch on everything as it goes up.
6. As the crane takes the weight (very very lightly) remove the clevis pins and any bolt at the mast base. Someone MUST hold firmly to the base of the mast at all times as some masts will try to invert if they are top heavy. If you have roller furling gear, then someone must hold this as well. If there are only two of you, you will be a little shorthanded so the person removing the clevis pins should leave the forestay to last so it can be held.
7. Lower the mast to the ground making sure it is angled so that your wind instruments are kept away from the lifting strop and crane hook. Be careful not to bend the furling gear foil. As the mast is removed, check nothing gets caught. I have seen rigging screws and shrouds catch on guard wires and cleats and this can easily go unnoticed. You may need and extra pair of hands to control the mast while you climb off the boat, especially if it is ashore.
8. If you have neatly tied everything off in sequence when the mast is removed, it will be much simpler and logical to refit the mast later.

I hope this is not too long winded!

Good luck.
 
Re: falling masts

Hello OldHarry I guess we are only differing in degrees.
The point I was trying to make is that it is handling the mast once it is down to near horozontal but still attached to the tabernacle that is the problem. It is the weight of the mast hanging back behind the boat that is difficult to get down to ground or down to the deck as I guess the poster needs to do.Lift and slide forwared with muscle power. Yes I agree the rear support should be as tall as possible consistant with being able to reach the mast to take weight to get it out of the tabernacle.
I do mine with ease but it is only 27ft long on a 21fter. I use 2 different mast supports one high to drop it into initially then a low one for transport.
I am really pleased you do it on your boat yourself as I too am a DIY person. olewill
 
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