The core goes right to the edge of the sump. If your core is wet around the keel, it will be most wet (and potentially rotten like mine) around the sump. Note the thickness of the inner laminate - this stuff is about 1/2 inch on top of 3/4 Baltec; that's very strong stuff. The outer laminate is VERY thin - we're talking less than 1/8 including the gel coat. This is all that is between the water and your core, so I strongly recommend barrier coat.

 

For this repair, I have stripped out the inner laminate using a circular saw and sawsall. I have also used a pneumatic chisel to chisel out the core (carefully) - its very easy to blow through the outer laminate. I have also used the chisel to pry off the glass roving that wraps around and down into the keel sump. This laminate wasn't that well bonded to the chop strand that is used primarily to bond over the core. This ensures I've got fresh and highly textured glass to bond my repair to.

 

My repair will consist of a layer of light biax on the outer laminate to beef it up. Core will be bonded with thickened epoxy and the covered with thick biax-mat hybrid cloth. Epoxy will be used for all repairs. All layers must descend down into the keel sump. Fillets will smooth the glass' route as it turns the corner from bilge to hull. New stringers will be fabricated from scratch and bonded with roving.

 

I would have loved to have done this repair from the outside, but I don't have the facility to flip the boat onto its deck.