Leisure battery brand.

geem said:
That depends very much on the boat and does not apply to all boats
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All boats behave better with more ballast in rough weather. In the Fasnet disaster the boats that became semi flooded became more stable. Many skippers reported this fact.
 
shanemax said:
All boats behave better with more ballast in rough weather. In the Fasnet disaster the boats that became semi flooded became more stable. Many skippers reported this fact.
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My boat weighs 19 tonnes loaded. The fuel, water and holding tanks are under the floor with a total weight of 1.3 tonnes. The batteries are higher than the tankage, located under the saloon seats. My 90kg of lithium or 230kg of lead batteries won't make any difference. There is 6 tonnes of lead in the keel with a draft of 2.2m
 
Haven't ever seen a yacht yet with a plimsol line and I know what happens to a yacht when their ballast drops off. (Keel)
 
geem said:
My boat weighs 19 tonnes loaded. The fuel, water and holding tanks are under the floor with a total weight of 1.3 tonnes. The batteries are higher than the tankage, located under the saloon seats. My 90kg of lithium or 230kg of lead batteries won't make any difference. There is 6 tonnes of lead in the keel with a draft of 2.2m
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Perhaps in your case you have enough but in the general rule of thumb the more ballast the more stable, that is why all ships can take on water ballast into huge storage tanks to make them more stable and I think even the smallest coaster is more than 19 tons. You say you are 19 tons but how much of that would be below the water line because your keel is less than a third of the weight of your boat which is not necessary a good ratio.
 
shanemax said:
Perhaps in your case you have enough but in the general rule of thumb the more ballast the more stable, that is why all ships can take on water ballast into huge storage tanks to make them more stable and I think even the smallest coaster is more than 19 tons. You say you are 19 tons but how much of that would be below the water line because your keel is less than a third of the weight of your boat which is not necessary a good ratio.
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Ballast ratios are not quoted by manufacturers for boats loaded up with all the cruising gear they could carry. The theoretical weigh of my boat, presumably empty, is 14.5t.
The boat has 6000kg of lead in the keel that starts from the bottom of the stub. The bottom of the stub is 3ft lower than the floorboards. The draft is 7'2". Ballast ratio means little unless you know where the ballast is positioned. With my boat there is a lot of weight deep down since we are relatively deep draft. By comparison to a shallow draft boat with the same ballast ratio. We would have a far greater righting moment.
 
One minute your boat is 19 tons the next it is 14.5 tons. I withdraw from this discussion. There is a saying about moving goal posts. Cheers
 
shanemax said:
I know what happens to a yacht when their ballast drops off. (Keel)
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They just sail higher in the water and go a bit wobbly but not a huge issue. The instructor sailing on the Cornish Cruising boat without a keel took several days to even notice.
 
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