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Sunday, October 26, 2014

Puzzle.














   
Boat design is like a puzzle.
But it has to be assembled in a certain manner to achieve the expected end result. Usually referred as  the "Design Spiral", but more about that later. To put a boat together requires a lot of time, patience and not to be lazy and afraid about checking, checking and also about double checking. The best way to save precious expensive time is to start with a very clear statement from the client  about function, purpose, destination, proposed budget and any other provisions that might alter the almighty weight of the vessel. I have seen too many times  where you start for the client with a Colin Archer and end up with a daysailer! It is crucial to narrow down early into the project The Choice. Trade offs and options will come soon enough. To illustrate, I am presenting L'Oceane 40', an Offshore boat with all the characteristics of a proper yacht with a look that demands respect. Respect of the sea being foremost in the delivery.
It always starts with a drawing, and as mentioned above a good description of what is expected. If given a free hand as far as the overall boat, it is important to nail down the type of accommodation plan as soon as possible. Yes, many boats are designed from the inside-out as shown with the shoe boxes production so prevalent these days, and this one is no exception except for the fact that by design the look can be rendered much better. The sketch arrived and surprisingly only few changes where made from the original. A separate shower, more space in the forward cabin and a modification to the table in the cockpit. Also a little later, the inboard rudder was switched to a transom mounted blade with a skeg, the easier way to install a trim tab for the wind vane part of the  installation.. 
Fail to plan, plan to fail as they say. So, a project starts on paper or rather nowadays with computer aided design programs. For L'O. the size was limited to 40' to avoid regulations over the 12M. limit. The envelop with the beam and the draft define her main characteristics. Draft is always a big decision making. In this case, a steel boat and no specific concern about shallow water, I felt comfortable with a depth of 6'-3" -1.9M. to achieve the stability and performance required.


You would expect to see a fin with a bulb at the bottom. Well, you see with a steel boat it is imperative to keep the ballast low but also to be able to keep within the foil fuel and water, sometimes batteries and pumps. Therefore I avoid bulbs which would implicate a thin upper shell. They are also a b.i.t.ch to build and there is nothing better that a well drawn foil from top to bottom. I favor a trapezoidal profile because the design brings the lead further forward and benefit of a longish top for added volume capacity. A far as the lines plan. Again, one has to adapt shape to the material medium employed. With metal boat, I favor three options. Developed chines; developed round bilge or the origami method which I call Imagiro.