Wednesday, December 20, 2006

The Hull


I should describe the hull - so those that understand these things can appreciate how unusual she is...
She is 6.85m long; 2.04m wide and approx. 1.3m deep ( this is not confirmed due to the waterline being wrong). She displaces 1040 kg and the mass of the iron in her keel is 600 kg. Her waterline length is about 5.2m.
My father described her as a"lead mine"; and in many ways he's right. The construction of the hull is as light as possible to allow as much mass in the keel as possible. She is probably delicate - but I'm not about to test her on rocks!

The hull is built with spruce on oak with a modified carvel construction. I'm not sure what the method is called, but I'll try and descibe it. The planks start at the keel, as with normal carvel, but run the entire length of the hull - from deck to deck. The only places she has any joins in the planks areat the stem and stern; where planks were cut in to remove rot. This allows all the end-grain to sit out of the water, clearly a good thing! It also allows for the simple round shape she has.
The deck has been replaced with ply - 12mm rebated into the originl oak beams, and 6mm covering the whole.
The coach roof, cabin and cockpit sides are all mahogany. The coach-roof being an addition in 1958 - prior she was a half-decker. The cockpit is completely re-built...

Originally the cockpit had pine open benches. Per removed these to replace with locker seats in mahogany. However mahogany would weigh too much - so foam-cored mahogany laminate was made and fitted. These weigh the same as the original - 42kg. - and keep the weight of the boat original. Now there is good storage in the cockpit, and the stern locker.
The form of the hull is descibed in swedish as "cirkelbågsform" - all the curves are taken from an arc of a circle, not from "french-curves". The deck is also an arc - giving a pronounced reverse-sheer. This is in my eye pretty - but she tends to push through waves. Her stern is flat, and she readily planes on the run. But she has a tendency to roll, an because of the lack of a sharp bow, can wander on the wind.

As mentioned she has 600kg in the keel - effectively a "long-keeler" with the new hollow stainless-steel rudder hung aft. The dead-wood of the keel has been replaced with Larch.

All in all, a well built Hull. With some design quirks that make her unusual, and very "typical" of design outside boats from the 40s and 50s....Streamlining and long,round forms!

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