It was a little time ago but the story might still be of interest.
My 890 ‘Wise One’ looked just fine, – except for a minor crack in the head lining between the heads and the hanging locker. A search all round showed that the cabin top step at the foot of the mast was inclined to starb’d. Not a lot; but a bit. A further examination showed that the deck to starb’d of the mast was depressed. Not much; but a bit. What was going on?
A boat builder and a surveyor were brought in. A trial hole drilled close to the mast base revealed the cause of the problem, (which, dear reader, you may already have guessed). Under the step is a plywood pad glassed in to the fabric of the boat to spread the load of the mast. That load is carried down to the bilge stringers via a stout hardwood 2m. plate which is also the bulkhead between heads and passageway to the forecabin. I will call this the mast plate. The deck shell is drilled through to take the electrical circuits to the mast and, over the years, that drilling had leaked into the plywood pad causing its eventual rot and collapse. (And mine). From here things got a lot worse before they got better. (What would you have done ?) #1.
This is what we did:
(1) Remove the mast.
(2) Cut away the head lining and
(3) Scrape out the rotten plywood.
(4) Apply a jack under the deck to pop it back into shape.
But Action 4 did not work since we were afraid of damaging the gel coat with too much pressure. So,
(5) with power tool, cross cut under the displaced deck to weaken it.
(6) Then jack underneath to raise the cabin top into alignment. |
(7) Introduce a ‘Spanish windlass’ utilising the mast step fitting and a long, stout lever over the port side. The purpose was to hold the deck in alignment while we removed the jack. (Are you with me?)
(8) Re-glassed generously under the weakened deck to (more than) return it to its previous strength.
Finished? Not quite! The 890 mast actually sits eccentrically over the mast plate being off set a little towards the passageway. It was built that way. “Not good enough” said my surveyor (who knew that he was going to be required to put his signature to the whole project). So now:
(9) Fabricate a 150 x 150 mm polished stainless steel bracket, made rigid with two flanges, to be bolted to the mast plate and to sit absolutely under the mast.
(10) To combat any ‘S’ bend stresses on the mast plate, a 50 x 50 mm triangular section hard wood post was bolted to the mast plate in the corner of the heads.
(11) Finally the very flimsy fastenings of the plywood main cabin bulkhead to the mast plate were beefed up to generally strengthen the cross rigidity role of that bulkhead.
The job was jobbed and better (it must be said) than in 1974. So what can a casual observer now see? Not a lot. Just one (surprisingly) discrete polished SS bracket in the passageway and a triangular corner post in the heads. Oh, and a varnished plywood headlining in the passageway to match with the other wood fittings there.
Anyone else had this experience? #2. Any comment from our Technical Officer, Mike? #3
Love to you all from Don Wark of ‘Wise One’.
(PS do get that electrical mast wiring well sealed in….)
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