Here is another "little" job involving fixing a leaking bow rail. There are few queries from time to time in this forum on this type of work, so I thought I would share my approach that I have picked up.
The previous owner tried to seal the holes with sikaflex, but unfortunately it wasn't cleaned up properly allowing moisture to get in the balsa core, in turn loosening the fitting, allowing more moisture to get in and rot out the core around the hole. The sikaflex also didn't seal very well around the wiring.
I ground out the holes and removed soft rotten core between the glass with a dremel tool. Dried it out from underneath for two weeks with a dehumidifier until the core edge was dry and dusty. Refilled with west epoxy filler. I first injected (with a syringe) a thin mixture allowing the rocking of the boat to work out the air bubbles and soak in, then I pasted of over the top a much thicker mixture. Let it set for a few days, sand then cover with a layer of glass, sand to shape, drill, countersunk and fill/seal with butyl rubber filler.
Off course, once the core is sealed with epoxy you could use Fixtech-15 (or similar), but I think for amateurs like me and a fitting like this where there is a bit of movement, butyl is more forgiving. It has been suggested that if you don't have time to dry out completely, then West G-Flex will set more successfully than standard west. I did this in another spot and it seemed to work.
It was amazing how much difference it made to reducing moisture content in the boat as water was pooling over the fitting and seeping in very slowly.

Almost all the core is removed from behind the white section.

Have yet to clean up around the bases.
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