Recoring the deck and cabintop

This is a massive job I have been putting off for years.  The yard wanted to charge me $30,000 to do it.  
One of the few differences between an Aqua 30 (aka S&S 30) sold in England and the P-J 30 as offered here by Palmer-Johnson Yachts was the center hatch added at P-J’s. Unfortunately, over the years previous owners did not attend to the bedding compound and the hatch/deck joint allowed water intrusion into the balsa coring. This led to rot and delamination which is starting to become a structural issue. Nothing for it but to cut open the deck and replace the balsa core.

“Peter Kronich is the best surveyor on the Great Lakes.”

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I was told this, in fact, by more than one person. Yes, it is true that he will absolutely refuse to board any boat in the presence of women, children, or animals. And, yes, he would also prefer that you also are nowhere nearby during the course of the survey. But this almost endearing eccentricity is a small price to pay, given his vast experience. So they said.

Therefore, this being my first purchase of a keel boat, and an old one at that, I put myself in his hands and vacated the area. The survey came back with no mention of deck/cabin-top moisture intrusion. The deck was “sounded” (i.e. tapped-on) and said to be “…solidly bonded and is structurally sound and stiff.” Being a paranoid type I repeatedly asked Peter, “Is the deck dry?” He gave what I now recognize to be evasive answers but at the time it just left me puzzled.

After the purchase I walked the deck and found two soft spots that sagged under body weight. Sounding these two areas gave a hollow “thud” and a moisture meter showed “off-the-scale” wet readings in these two spots. Also noticed was that the port side deck is raised in a dome shape and yes, rings hollow and reads “very wet”. (In fact, this last fault seems endemic to the model: two other owners of S&S-30s in Europe report the same issue. Shroud tension has caused one side-deck to lift and separate from the two structural sub-deck knees on that side.)

But somehow Peter The-best-surveyor-on-the-Great-Lakes Kronich missed all of this.

Deck Recore, cont.

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New 1/2″ Baltek end-grain balsa core cut and laid in place, ready for bonding to bottom fiberglass skin. Just forward of the mast hole can be seen two internal backing plates of G10 (aka FR4), which is an epoxy-impregnated fiberglass cloth laminate material. Just a corner of each (green) can be seen protruding from beneath the top skin. Everywhere there is a highly loaded deck fitting I will be incorporating this in place of the balsa core material; no external backing plates needed.

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Internal bracing to support the sandbags which will be loaded on top of the balsa core to insure good epoxy adhesion to the bottom fiberglass skin.

Cabintop

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Top fiberglass skin added; two layers of 1708 biaxial E-glass topped with a final layer of 10 oz. fiberglass cloth. This will be the “layup schedule” for the foredeck and side deck repairs as well.

Along the sides of the cabintop the original decking containing the molded-in pillars for the teak handrails was reused.

Foredeck

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Shoring up the foredeck while work proceeds. Also, taping up screw holes to prevent “epoxy rain”.

That reddish-brown area is where I had injected some "snake oil" into the deck to firm up a soft spot.

When cutting into the foredeck top skin the saw threw water up into my face; that’s how wet portions of the balsa coring was in this area – totally saturated. All rotten, wet or damp balsa core is now out. The reddish-brown staining is where I had injected a “snake oil”-type product to firm up the mushy deck. Unfortunately, the only real cure is what I’m involved in right now.

Wait a minute.  WHICH boat is mine?  I keep forgetting.

Now wait, WHICH one is my boat again? I keep forgetting.

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New balsa laid in place. Edges scarfed for top layer of glass. Three G10 fiberglass/epoxy internal backing plates in position, two for bow pulpit and one large central combination plate for bow cleat and inner forestay attachment point.

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Bags of sand hold the balsa coring in place while the epoxy hardens.

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Top skin on, sanded, and ready for fairing and painting (which will come later).
So that’s the cabin top and foredeck recored; two sidedecks to go. Time on project so far, 250 hours.

Port Sidedeck

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Totally water-saturated, black, rotten balsa here among the chainplates. No surprise, as the boat has a major structural fault in this area (missed, of course, by Keystone Kop Kronich the surveyor). Not only on this boat, but also on the two other S&S 30s I have identified in Europe, shroud tension has caused a sidedeck to lift away from the two knees on that side that tie it into the hull. This caused delamination and water intrusion in a big way.

Deck deflection, chainplate welds and tight corners

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Port side deck open and fully undercut.
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But the aft ends of both side decks become very narrow next to the cockpit. My tools cannot reach the wet balsa in these two small regions (about the size and shape of a man’s hand).
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So another method has to be used here: drilling holes and drying out the balsa in situ using acetone and heat.
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I did the starboard side at the same time – its even wetter than the port side.
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Underneath, I ground away all the fiberglass cloth that tabbed the side deck to the knees. The failure of this tabbing is what allowed the tension on the cap shroud to lift this side deck by 5/8″ (16mm). IMG_0075
This plastic deformation is effectively permanent. Even my jumping on the side deck lower skin (upper skin and coring are gone) deflects it only a paltry 3 mm. (The encapsulated chainplate stiffens things up a lot.) So I can’t come close to generating the force necessary to push it back down into position. I’ll just re-tab it securely where it is.
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Here’s what its supposed to look like; the aft knee with tabbing removed. This part of the side deck was not pulled up, probably because the tension on the lower shrouds is so much less.
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And here is a clue to why this may have happened in the first place: poorly laminated tabbing in this area.
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An oddity of this design is the horizontal chainplates. They run under the side decks. This is why tying the knees to the side decks is so critical. Being encapsulated in fiberglass there is no way to inspect them for corrosion. This is especially worrisome at the welds, where the heating could have caused chromium depletion, leading to weld decay. Therefore, I removed a bit of the sealant where one chainplate comes up through the deck to get a look at a weld. As bright as the day it was made, thankfully.

Deck recore almost complete!

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Knees re-tabbed with three layers of cloth, each side: 1708 plus two layers of 8.7 oz. cloth tape. Bulletproof.

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Port side deck with the new balsa dry-fitted in place.

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Paper template from the side-deck laying on the 1708 biaxial cloth.

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1708 cloth marked and ready for cutting.

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Balsa core epoxyed in place and ready for the glass.

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On left, chainplate heavily core-bonded to isolate it from the balsa. On right, a G10 internal backing plate for the staysail sheet lead attachment point.

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First layer of 1708 cloth in place, waiting to be wet-out with epoxy.

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Three layers in place; two of 1708 biaxial E-glass plus a top layer of 10 oz. cloth.

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Starboard side-deck getting the same treatment. Here, all wet balsa has been removed.

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New core dry-fitted. Edge balsa and G10 internal backing plates already epoxyed in position.

Time on project so far: 402 hours.

Now we work on appearances.

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Filled, faied, and sealed that big dent we got in the keel when we hit an uncharted rock in the Moon River area of Georgian Bay, Ontario last summer.

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Cabin-top and foredeck are faired and sealed with epoxy.

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Port side deck with first application of fairing compound, before sanding.

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They moved me into the “showroom” with all the new boats for sale. We look quite shabby by comparison. But this older building has lights controlled by a wall switch! The previous building’s lights would go off if you sat still for a few minutes – very irritating.

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Starboard side deck with second application of fairing compound, not yet sanded.

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Port side deck, second application of fairing compound, sanded but not yet sealed with epoxy.

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Starboard side deck sanded and ready for sealing.

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Fairing complete. Ready for painting.
Total time on job so far: 584 hours.