# thesis in "design of 15m wooden sailboat with keel" - help with weight calculations

Discussion in 'Boat Design' started by unverrr, Aug 5, 2015.

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### unverrrNew Member

Hello everyone
I am doing my thesis in "design of 15m wooden sailboat with keel".I have to do weight calculations. Could you help me about this?

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You will need to provide a lines plan, specification and general arrangement before anyone can even attempt to assist you.

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### unverrrNew Member

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### gonzoSenior Member

Do you need the total weight or are you looking at finding the center of gravity?

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### HeimfriedSenior Member

@ unverrr

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### TANSLSenior Member

Explain to unverr, and everyone else, how to calculate the center of gravity without calculating the total weight. Thanks a lot.
Unverr, I'd start working as indicated by AD Hoc and then calculate the scantlings of the ship.

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### unverrrNew Member

I can fınd center of gravity. I need only weight of materials( mast,jenerators, batteries, beds, sofas). I also know weight of main engine, keel, hull.

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### gonzoSenior Member

It is simply the sum of all the materials. The job is tedious but fairly easy. Finding the centroids of each makes some calculations faster. For example, if you need to move things around.

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### PARYacht Designer/Builder

Now the center of masses calulations are simply a spread sheet issue, but I think all prospective designers and NA's should be required, to perform this task at least once by hand.

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### TANSLSenior Member

Although not fluent in English, I think "centroid" and "center of mass" is not the same thing.
To calculate weights and centers of gravity, the center of mass is used, the centroid is only for flat regions.
And I agree with PAR, everything should be done at least once, by hand, to avoid errors, such as the centroid, for example.

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### keroseneSenior Member

and if one is doing thesis one would think they have been given the knowledge by the school or at least have people from whom one can ask.

So that you don't have to ask from web forums.

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