Dismantling aluminum mast.

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Dismantling aluminum mast.

Post by HADDOCK »

Hello, I should buy a 1987 Freedom 35 with 2 aluminum masts. I would like to remove the masts this winter in order to control them properly. Does anyone have information to help me do this operation (documentation, photos, advice, etc.)
Beautiful day

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Re: Dismantling aluminum mast.

Post by arrancomrades »


Is it a UK-built boat, in which case it will be very similar to mine? The first time you do this it may take as much as one day per mast.

First of all, measure and photograph exactly where the masts are at the keel, to the millimetre. Sideways and fore/aft.

Disconnect wires and antennae and remove most or all running rigging.

The masts should be glued into the 'ashtrays' (rings) on the keel. Maybe with Plastic Padding. You need to remove 2/3 of this, leaving the narrowest part to give the position for putting the masts back. Drills and chisels and patience. There may be a bolt at the heel of the mast. Remove it.

If any furniture, like the table, is attached to the aft mast, remove this, again taking notes.

Best with two persons, take out all the bolts at deck level. Remove any waterproofing above the deck. Maybe silicone injected between the mast and the ring?

Rig some sort of strop on the mast with a block and tackle (maybe 4-part) to the ring and tension with the cockpit winch. Do not use the halyards for this as you can damage the masthead. Wait. It the tension does not break whatever is holding down the ring, use a second tackle and wait again. As a last resort, maybe try to get wedges or a hacksaw blade under the ring.

Once the ring is out of the way, there should be a rubber strip between the mast and the hole which is tapered. Use wooden strips to hammer the rubber upwards. Maybe try to find the join and use a big screwdriver from the top. If the mast has not been removed recently this may be quite a problem.

Hopefully the mast will move enough to break free from the remains of the Plastic Padding.

Once the rubber is out, insert small wooden wedges from the top to keep the mast steady until the crane is ready. The rope should be about the height of the wishbone hoist block (or higher) leading off the forward side and hitched at least six times round the mast about a meter above the deck. The mast weighs 120kg and all the weight is at the bottom. Pull out.

When you put the mast back, put something like polystyrene at the bottom of the mast so that the Plastic Padding does NOT go all the way down. Use grease for the rubber ring, sort out the deck bolts, use a minimum of sealant under the deck rings and use a self-amalgamating mast boot rather than silicone above the deck. And remember to put the wishbones and rings in place before lowering in the masts.

Next winter you will keep the boat afloat or find a yard where the masts may remain up - for ever!

Best of Luck
Mike Johnston

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Re: Dismantling aluminum mast.

Post by Castaway »

Hello, Haddock,

I have a Freedom 35 as well, though it has only one aluminium mast, the forward one being carbon fibre. The system for removing is the same as Mike has described, though there might be some different packing around the base of the masts than the resin he mentions.

I would add a few points to his description. Removing the deck level collars is definitely a two person job, since the collars are held in place by a nut on either end of a stud; the upper one is domed. It isn’t necessary to withdraw the studs, but it can’t always be avoided. It is very awkward to reach the internal nuts on the forward collar, through the hatch in the fore-cabin. It helps to use a pillow over the edge of the hatch, and some long extension pieces on a socket spanner, plus a head torch. You might need to shift the anchor rode, too.

There will be sealant around the mast at the upper collar, which will need to be removed before you can lift the collar or get at the mast wedge. In contrast to Mike, I usually use a sharp paint scraper or a thin, flexible knife, to free the collar; it depends how firmly it is stuck on. Just hope the P.O. didn’t use Sikaflex!

The polyurethane wedges or partners were originally cast in one piece, in which case they can be slid up the masts, then down again after re-stepping. Mine, like most others, I suspect, are in three or four pieces, and can be levered out one at a time.

When stepping the masts next season, I recommend putting some sealant (polysulphide rather than Sikaflex or 3M, since it doesn’t set hard) around the studs where they go through the deck, since one can easily have an annoying leak there, despite sealant and boots around the mast, etc.

Whilst you have the masts out, take the opportunity to remove all the internal wires, leaving a messenger or two in place, then put cable ties in a star formation every one or two metres along their length, and replace. A spare messenger is a good idea, too – don’t bundle that with the cable ties. The stars prevent the cables slapping inside the masts, which will keep you awake when at anchor!, especially of you sleep in the forward cabin, which tips the boat a little and leaves the mast vertical.

You can search this board, and you will find a lot of stuff about the masts, wedges, sealing the collars, and fixing the wires; well worth reading up. Once you have it all sorted out, as MIke says, leave the masts up forever, or as long as possible. I have had ours out three times in twenty years, and that was two times too many! We keep Castaway outdoors year round in Sweden, and she has come to no harm as a result, though we do need to spend a little more time removing gear, applying covers, etc., and there is more cleaning to be done in the spring. Much easier than a couple of days just getting the masts unglued!


Gerald Freshwater,
s/y 'Castaway', (UK F35 cat ketch, centreboard, 1987)
Lerwick Boating Club
Shetland Isles, Scotland

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Re: Dismantling aluminum mast.

Post by HADDOCK »

thanks for all the explanations. Have a good evening

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