Normally, when you're installing deck hardware over a core, you grind out the core material around the opening and fill it with bearshit (resin thickened with chopped strand). This takes the compression loads if you're through-bolting and provides a better hold if you're using screws.
Just as importantly, it seals the edge grain of the core material.
It looks like that was done with the original installation, judging by this pic:
Jims Scampi 30 - wierd chainplate covers
Epoxy thickened with cabosil should also do the trick, but some new coring and a layup are DEFINITELY the 'right' way to do that repair.
SD, for once I've got to disagree with you about balsa core...it's absolutely awful for compression loading, specifically from through bolts. Last fall, I laid up new primary winch pads on a homebuilt when the new owner wanted to use electric winches.
The bolts had been overtightened and compressed the balsa (like overdriving a wood screw). It was sealed up well so no water got in but the glass was spidercracked all around the fasteners. A leak in the seal could have (in time) pulled the loaded winch right off the deck. Ouch.
An advantage of using marine ply as a hard point in the core is that the veneers have a bit of 'spring', allowing the bolts to stay under tension.
Just as importantly, it seals the edge grain of the core material.
It looks like that was done with the original installation, judging by this pic:
Jims Scampi 30 - wierd chainplate covers
Epoxy thickened with cabosil should also do the trick, but some new coring and a layup are DEFINITELY the 'right' way to do that repair.
SD, for once I've got to disagree with you about balsa core...it's absolutely awful for compression loading, specifically from through bolts. Last fall, I laid up new primary winch pads on a homebuilt when the new owner wanted to use electric winches.
The bolts had been overtightened and compressed the balsa (like overdriving a wood screw). It was sealed up well so no water got in but the glass was spidercracked all around the fasteners. A leak in the seal could have (in time) pulled the loaded winch right off the deck. Ouch.
An advantage of using marine ply as a hard point in the core is that the veneers have a bit of 'spring', allowing the bolts to stay under tension.
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