Hi Don,

What stage of construction are you in? And how extensive is the "dip"? Obviously, the hull has been stitched together. I am guessing that you have taped and glassed the skin joints on the inside of the hull already, but not the outside?? If so, my recommendation is to remove the stitches, and use a hacksaw blade to cut through the taped joint in way of the dip. Spread the hull sections enough to bring it back into fair. Inserting small pieces of toothpicks between the hull skins will keep them apart. It is surprising how small a gap that will need to be forced into the keel line to get it back into fair. Then, unfortunately, you need to re-tape the inside keel line to "freeze" your fix.

After turning the hull upside down, you will find your keel joint will have some "gap-osis" from the toothpicks that are now firmly epoxied in place. No worries, mate. Simply cut them off flush with the outside of the keel, fill the gaps with microballoons or other fairing compound, and fair any minor remaining irregularities before you tape the outside of the keel.

And you are back in business, with assurance that you have not compromised the structural integrity of the hull in any way, and you now have a nice, fair hull. A bit more work, but well worth it, in my opinion.

Regards,

Pete