stem parts

Greetings to all, I ask you if there are tables / sheets to size the parts that make up the keel, stem, fore deadwood, apron, hog, of a sailboat taking into account its length,
thank you.

 

As I assume we are talking wood, have you decided on the fastenings and construction? A lot of the scantling "rules" and structural members are sized to the chosen construction/fastening method and planking thickness.

 

No "tables" that I know of.
For traditional construction using the structural members that you've stipulated, there are 3 basic sets of scantling rules.
Lloyds/Nevins/Herreshoff.
Lloyds rules will produce the heaviest boat, more suited to commercial craft.
Nevins rules will produce a lighter boat, think of a classic Alden schooner from the 1930s, (a strong yacht).
Herreshoffs rules produce the lightest weight, but VERY GOOD craftsmanship and materials are needed to produce a long-lived and sufficiently strong boat.
In the book "Elements of Yacht Design" their is a passage, (paraphrasing,) "One should not attempt to go lighter than Herreshoffs rules lest the boat break up".

 

I guess you're talking about scantling numeral dimensions - wood vessels: length x breadth x depth. I mean tables for wood construction - main structures. ?

 

For a more modern book, Elements of Boat Strength will give you that information. The dimensions (scantlings) are conservative and give hulls of moderate weight.

 

The existing books, or the scantling regulations that we usually use, do not tell us how to design a structure. Some construction details or "good practice" are indicated, but they only give us the scantlings of the structure that we have previously designed. A good design of a structure can save much more weight than the blind application of certain rules, whether they are conservative or not.
You can study various solutions for a given structure and the formulas will indicate which is the solution with the minimum weight or which one best suits the requirements imposed on the structure.
There are several objectives to achieve, and not only the minimum weight, which determine the final scantlings of a structure.

 

Herreshoff is too "brainy", I tried to interpret the rules and references of the fundamental factors but I had a lot of difficulty, I find it easier to read and interpret the sizing rules reported in Dave Gerr's book "the elements of boat strength"; shows you step by step how to size the parts of the boat.

 

The calculation of small boat structures has improved a lot in the last 20 years, especially that of composite materials. The old formulas, very easy to apply but no one wondered where they came from, have fortunately been replaced by more sophisticated procedures that require some, though little, knowledge of the strength of materials. And I say fortunately because that helps us to achieve much better optimized structures.
When working with composite materials, it is no longer sufficient to calculate the global resistant modulus of a panel, but rather a detailed study of the forces existing on each of the layers must be carried out, verifying that they do not exceed, in any of them, the design stresses. There are entities that without this detailed study would not approve a laminate scheme for a hull. So the formulas that give global values for the compound of a laminate may no longer be usable. Not to mention the weight gain, which can be more than 10%.
Wooden hulls are also currently calculated by more complex procedures than those of 2 decades ago.
In my opinion, therefore, it is worth forgetting the obsolete texts, which were extremely useful for the uninitiated a few years ago, and trying to apply the currently accepted procedures. Given the number and variety of calculation tools available to the designer, it is not justified from any point of view not to try to achieve the most optimized structure possible, in terms of weight and workmanship. The good designer cannot settle for a "reasonable" weight structure but rather try to achieve the minimum weight.

 

That's a fair statement.
The "Old man", Nat Herreshoff, was an MIT guy, and many times after running the numbers he would make a scale model of some structure and then test it to destruction to determine the areas of failure to be concerned with.
The above post by TANSL is largely concerned with weight, well, Nat was too, that's why the Herreshoff boats won races.
They were quite light for their day, built for the "carriage trade", rich people who could afford a new yacht like most people today would change cars.
The "Try to achieve the minimum weight" philosophy works for "throw away" race boats, (remember the Americas Cup boat that broke in half,) but it's a fools errand for a long-lived cruising boat.

 

While that was a scantling issue, it was due a New Zealand exploit in the 1995 , 2000, 2003 cups. But they got hoist by their own petard in the 2007 cup. And it is not longer the "America's Cup"; that was destroyed in 1997