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.

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