Affordable seaworthy cruiser

Greetings,

GTO, Have thought about putting 1/2" plate secured to bottom of hull. This was done with AS39 "Anemone". It would put 5500lbs at the bottom as ballast. BTW others have used copper eliminating antifouling and good grounding plate, its just to expensive.

Steel prices in Cleveland are about $.70lb. Can be bought 8' x 24' x 1/2" that would be about $5,400.00 for two. If it could be done properly there are many advantages, the extra costs might be worth it.

How do you secure it to wood hull?
What about condensation?
Corrosion of fasteners and plate itself would be a major concern.


Pierre,

Never said Jubilee was a proven design, it still needs tweeking. The other boats especially AS39 are the proven ocean boats.

In regards to bouyancy, the COB was never calculated. If correct would that be like taking the hull at a certain point at bottom and and balancing it? Know that there is a relationship with COB, CLR, and COG with determining sailplan.
Without knowing exact COB it seems to be about 60% aft if using above method of calculating works. From other sources found out that COB should be in front of CLR for straight steering, which with the full keel this seems accomplished. COG is not know either but know the lower the better.

Glad you brought bouyancy up, as this and the others need to be determined.

The forward area has been intentionally kept light as this is a good thing, maybe the main mast so far aft is not good for keeping COB amidship, dont know.

One reason for original concept with leeboards was final placement of poured ballast would be done with boat in water and correct trim could be adjusted.

Does balance while riding have anything to do with COB? Did tuck the stern in to help with balance but needed bouyancy for engine and cockpit. Double ended would have been good and more easily driven as most cruising planned is to be about 1.0VL, this is low but with long hull speed is still over 7kts. with low hp engine requirements.

With replies try to keep on topic with answers that pertain to questions asked. Thankyou.

 

Oh bouy, pun intended.

Das boat is not apt to flip over end to end but side to side.

 

I think it could have the stability to stand up under sail . After all Bolger,s AS39 kind of prove it.

 

Scaled up to some 60ft by a complete novice? You are joking.

 

Apex,

Accept my apologies, realized that your project is in a very different catagory and remarks made were not helpful.

Pierre,

Not averse to adding flare and more displacement if it needs to be. If those are things you feel are required, better explanations need to be given.

Thinking about unsinkability, for ballast rather than the heavies, would it be possible to just add a bunch of wood at bottom. Additional advantages would be:
Low cost
Strength
Quieter
Insulation
Reef proof

 

While adding some flair will help to reduce roll rate , dont forget that the added weight of the deck will require more ballast placed lower . Beside it changes the whole concept, and then you start to end up with endless changes that go nowhere.
You could end up with a hundred different designs.

 

I has nothing to do with making the boat more top heavy. It has to do with how the center of bouyance behaves in relation to the center of gravity on a flat bottom boat as the boat rolls over.

 

Frank,

Youre right, dont want to get into constant revisions.

Pierre,

What are the things you think will happen with relations of bouyancy and COG? Looked at Bolgers diagram of square hull righting arm and resistance to heeling. Its not completely understood but it does show its possible.
What do you think should be done with improving your concerns?

The change to a full keel definetely seems and improvement to ocean work and should help in several areas:
Lower center of gravity.
Shouldnt be thrown around as much by wind.
Less tendancy to stall.
Passive-less attention.

 

How will a 'full keel' give you less tendancy to stall?

 

Samsam,

Isnt lower aspect always less likely to stall?

 

Goody,

not to bother you, but when will you stop to try getting a free ride on Naval Architecture here?

Start where you should have started weeks ago:

http://www.boatdesign.net/forums/boat-design/design-spiral-where-start-building-boat-28580.html

instead of hopping from one invalid argument to the next.

The boat you dream about is not on the market, cannot be build, and does not make any sense. period

IT IS NOT POSSIBLE; NO MATTER HOW MUCH YOU WOULD LIKE IT !!!

 

Exactly and then go to library and read Gerr's nature of books just to get an idea how one boat is good fr one thing but not for another.

Then read the Principles of Yacht Design (Lars Larsson, Rolf Eliasson)

Its silly to want to avoid repetitive revisions and calculations when current shape was not result of such procedure anyway. You really have to have a clue of COB and COG stuff and much more if you think you can design a boat.

what the hell is that supposed to mean? its not quite understood by you or it is not completely understood by people in general. You should very much be able to figure out the righting momentum before you start making blanket statements here.

People are not making fun of everyone who is wrong on this forum - just the stubborn ones who keep on insisting that their wishful assumptions are same as truth.

I can sketch in 10 min crappy blue water boat and come here and tell everyone how great it is. I might have even put thought into it in the format of "I want canoe stern so it doesn't get thrown around as much and has lower resistance" etc. Even if every single IDEA was right I would likely end up with terrible hull unless I followed a rigid controlled procedure and checked different calcs - and most importantly changed accordingly.

 

One last pennies worth. I have personally seen...
Million dollars boats, designed by famous designer. Engineer by expert naval architects with countless designs.
Built by world renown shipyards using the best of the systems and materials
Be built and after the first couple of sea trials the boat has needed major redesign or even scrapping because it would not function as designed.
Imagine a boat being built by pure luck in your head.

It is almost like thinking that the living organisms just happen to evolve to bipedal human "somewhat intelligent" form factor by accident.

 

the evolution analogy is pretty useless in this particular thread...

 

I mention it because Goodwill was mentioning something before about it. The point is good boat designs don't happen by accident.