Last winter I grinded down the bottom on the stern, bow and sb side (a nasty job).
At the stern and bow some cracks appeared. I found that there is a groove (app.
5X5mm) along the centre line of the hull. This groove is filled with gelcoat and I
believe that the hard gelcoat in a thick layer causes the cracks. I removed most
of the gelcoat and filled the groove with 2-component epoxy filler. It looks like the
boat has been assembled in two half parts? Don`t worry - these boats are extremely
strong! Finally the grinded gelcoat was covered with 6 layers of epoxyprimer before
adding new antifouling.
Hello Mr Pepe
Great Danes are not assembled in two parts. I`ve had problemes with my GD for some years ago and talked to mr. Baess. He said that GD`s are made in one piece !!!
Well
I can only confirm Mr Pepes observation. Let me just state that the polyester-puttied groove is an even deeper mystery if the hull is made in one part.
Having observed the two hairline fractures already in the early 1980s, extending from the waterline down to the knee of the keel both fore and aft, I quickly decided to do something about them before Nepenthe would have a more seriously "split personality". The peculiar thing is that there is no trace of this peculiar feature above the waterline despite some rather fierce impacts. The slowly progressing cracking up of the gelcoat on large areas particularly midships high on the freeboards and on most of the flat surface of the stern is a completely different story that I will come back to later.
I removed all paint around the suspicious area, ground out the groove and reputtied it with expoxy putty. Then I laminated it over with several layers of glass fibre and West laminating epoxy finally fairing the whole thing up with more epoxy putty and covering it with five layers of International Gelshield 200. That spring, the people at the wharf started betting if I would get her in the water at all before summer was over. I vividly remember standing under the bow pressing the wet glass fibre against the hull when the whole strip fell over me. I can only say one thing - don't do this kind of work wearing your best clothes! Epoxy is pretty irritating stuff to the skin as well. Over the years, I have progressively got more and more sensitized to it and the last two times it made contact with my skin, I developed a pretty severe rash that took several days to go away. Wear gloves and don't let it come in contact with bare skin at any time!