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mystymike
18-11-03, 15:49
I have a Macwester Rowan 22 (Pocket Cruiser) which I sailed for the first time this year and have had good fun with it so far. I suspect though that the ballast is a bit light on my boat. I exposed the ballast weight by removing the GRP covering last Spring to examine it and found it to be encased in foam, I read on a Macwester website of encasing the weight in concrete!. The specification ratio is 28.5% and displacement is 2286 kg with ballast at 652 kg. My question is can I add extra lead around the bottom of the weight and how much, to give my boat better stability in the "chop". Thank You.

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Avocet
18-11-03, 22:32
I don't know anything about Mcwesters but if the boat floats to her correct waterline, I'd be wary of adding any extra. Maybe you could keep the total weight the same and lower the centre of gravity by using lead lower down but it seems like a great deal of work!

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AndCur
19-11-03, 12:32
Have you ever heard the old saying if its not broken why fix it. The designer will have put a lot of time and thought into the ballast and where it is positioned and what weight. You could easily end up setting the balance of the boat.

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AndrewB
19-11-03, 13:55
I'm for adjusting ballast if you want to alter the 'feel' of a boat to your taste. And with a ballast ratio of 28%, it sounds like there may be some scope, though presumably the designer knew what he was doing.

Fitting a "shoe" to the keel is sometimes done with an iron keel, in part to provide a sacrificial protection as well as to increase weight. But I haven't heard of this being done with a lead keel. Perhaps there may be a question as to whether a strong enough join could be made in a soft metal. Having lead keels recast is occasionally done.

Bear in mind that adding to the keel will not just make the yacht stiffer but will affect balance in a number of ways, and it is important to get the correct fore-aft distribution.

It may be easier, certainly for experimentation, to install moveable ballast low down inside the yacht. If you do this make sure it is firmly secured in the bilge. Lead pigs are about 1 per kilo, typically about 25kg each. Iron is a lot cheaper, but not so heavy and can be very messy as it starts to rust.

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MADFISH
20-11-03, 10:06
Adding weight to a lead keel is possible.

I added 100kg of lead to the bulb keel of a sportsboat I used to race. We did it by gluing and screwing lead sheeting to either side of the bulb, then hammering the edges then filling and fairing. The designer was consulted on this (Stephen Jones). He said this method would be fine.

However, I understand the boat in question has encapsulated keels. This makes the above operation unpractical.

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Richard_Blake
20-11-03, 11:06
You mention "in a chop". Are you rolling, pitching, or just heeling too much? Maybe the answer isn't adding, but distributing weight. We had some success (slowed the roll, reduced pitching in the horrible Ijsselmeer chop) by playing with 4 10-litre plastic water containers to find out what improved the movement. Then we replaced the water containers by shifting stowage of heavy items, and moving some of our internal ballast around. May have been beginners' luck of course. Perhaps the more experienced can suggest a logical approach or sequence for experimenting with weight distribution, and how much it might help your type of boat?
Richard

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Oldhand
20-11-03, 11:22
If I remeber correctly the Rowan is a beamy boat and was probably designed to have a lot of "form" stability. From what I can remember of her hull shape, she would also like to be sailed flat and would tend to do windward braoches in gusts if allowed to heel too much, just as the Macwester 27 did. With the shallow draft, adding ballast may not help much and would probably mamke her motion in pitch and roll more "jerky".

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birdseye
20-11-03, 17:04
take the wife / girlfriend / live in lover on a 2 week cruise. you'll have no worries about ballast - i can vouch for it!!

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mystymike
20-11-03, 17:53
Thank you all for your great response to my question. I bow to your experience as this is my first year sailing a keeled hull. The Rowan 22 is a long keel with a shallow draft of 0.83mts and does not have bilge plates fitted.It has an encapsulated solid iron ballast weight. The space is easily accessed through the thin GRP sub-floor in the cabin without infringing the integrity of the hull. This little boat sails very well in moderate conditions and has several times topped 6 kts but it heels more than I like. In a test report back in 1976 it says:-"The Rowan 22 would be a better boat with a little more on the keel". My boat is a modernised 1980's version with rolling reef Genoa and stack pack/lazyjack main with a Beta engine that comes a bit futher into the cabin than the original did. My sailing area is the NW coast of Donegal with many good sailing days into the Winter. I would prefer my boat to be 'steadier'and more in keeping with my pensioner lifestyle. I will try adding 100kg of lead as low down as possible with the option of more or less on trial. (I believe that 100kg will sink the hull by 15mm) I am open to further education by yourselves and I will not do anything to upset the balance !!!..... Many Thanks.

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