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Old 06-12-2012, 23:51   #1
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fore and aft trim

I have recently purchased a 41 ft fast cruising yacht a modern design with
a bulb keel, plumb bow and fairly wide aft section. During a recent internal clean and locker inspection I found that the boat has numerous lead ingots in lockers forward of the mast. these were not very well secured and i want to glass them onto the hull. My dilema is that i dont understand why the former owner/builder has placed this lead in three
diffrent positions. All on the center line but at least 4ft apart. Iam sure it
was added to counteract the weight of motor ,fuel tanks etc in the stern.
would i be better off using less weight and putting it further forward ?
OR even more weight and having it closer to but infront of keel? what are
implications ?? (total weight of ingots is aprox 200kg)
Any ideas?
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Old 07-12-2012, 00:24   #2
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Re: fore and aft trim

What about using a heavier anchor and more chain and put that weight to some use?
Most people have the opposite problem with too much weight at the front!
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Old 07-12-2012, 01:31   #3
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Re: fore and aft trim

Only thing that makes sense to me is for racing. Either trimming the boat bow down to get a better handicap under a rule or bring the boat up to minimum weight for a one design class.

My boat came to me with all the batteries in the bow, and the 40 gal fuel tank under the cockpit taken out and replaced with a 20 gal tank in the keel to trim the bow down to get this old CCA racer a better rating under IOR.
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Old 07-12-2012, 04:12   #4
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Re: fore and aft trim

I wouldnt glass them in until i knew "exactly" why they were put there. Frankly, I would get in contact with the previous owner and ask him.
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Old 07-12-2012, 04:15   #5
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Re: fore and aft trim

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Originally Posted by Seaworthy Lass View Post
What about using a heavier anchor and more chain and put that weight to some use?
Most people have the opposite problem with too much weight at the front!
That would have the weight up too high then. Good idea if it were just a trim issue. But they were possibly put low to also assist righting moment.
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Old 07-12-2012, 04:25   #6
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Re: fore and aft trim

They may be loose so they could be moved while sailing. It is normal to move weight amidships when upwind, or forward when in light airs, and move it aft when downwind to counter the bow down moment of the sails and help planing.

Achieving this through having loose lead in lockers doesn't just smack of cheating, it is downright dangerous for your crew. Even an almanac flying across the cabin in a knockdown could cause serious injury. A lead ingot would be fatal.

By far the best way of trimming the boat is moving water between fore and aft tanks (it is usual practise to use the bow tank first to bring the boat by the stern). As an aside, moving water between side tanks when upwind is tempting, but normally against racing rules. If you can't contact the owner, my advice would be to lose the lead, unless you feel the boat is trimmed excessively by the stern without it (large stern wave and rushing noise of water trying to catch up with the boat).
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Old 07-12-2012, 04:40   #7
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Re: fore and aft trim

"numerous lead ingots"

How many, how heavy?

I just can not get my head around movable lead ballast having any real purpose on a 41' cruising boat. By the time you put enough of them on a cruising boat to made any difference you are talking a lot of weight! I put 300+ lbs of extra chain and anchor on my bow and it didn't really mad any notice difference in trim some how many lead blocks are we talking here?
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Old 07-12-2012, 04:44   #8
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Re: fore and aft trim

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They may be loose so they could be moved while sailing. It is normal to move weight amidships when upwind, or forward when in light airs, and move it aft when downwind to counter the bow down moment of the sails and help planing.

and in the old days of sailing frigates, to get that last increment of speed in a stern chase to catch another ship. Read the "Ramage" novels and there are semi-regular mentions of seamen carrying cannonballs tramping around the deck for here to there.


Just how serious are you to get every last bit of speed out? Maybe just slap in an extra battery bank forrard? As Tim Taylor always said, MORE POWERRRR!
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Old 07-12-2012, 07:21   #9
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Re: fore and aft trim

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and in the old days of sailing frigates, to get that last increment of speed in a stern chase to catch another ship. Read the "Ramage" novels and there are semi-regular mentions of seamen carrying cannonballs tramping around the deck for here to there.
Another useful trick was to run out the guns on the windward side when beating. Made the boat just a tiny bit stiffer.
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Old 07-12-2012, 07:48   #10
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Re: fore and aft trim

The ballast being found on the centerline indicates fore and aft trim, possibly to counteract crew weight in the stern when racing. Dragging the stern through the water is slow. I would sail the boat and assess best trim. Really no other way. I doubt very much lead ingots being shifted around when racing.
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Old 07-12-2012, 10:13   #11
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Re: fore and aft trim

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.....Achieving this through having loose lead in lockers doesn't just smack of cheating, it is downright dangerous for your crew. Even an almanac flying across the cabin in a knockdown ......
To me it's downright dishonest shifting ballast when racing. This is not only against the "rules", but against the whole spirit of racing competitively. What is the pleaure in winning knowing you have cheated to do so?
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Old 07-12-2012, 10:23   #12
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Re: fore and aft trim

maybe the boat is a bit tender and it was an atempt to add a little ballast? How much have you sailed the boat? I would take them out, sail and then decide what to do.
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Old 07-12-2012, 10:28   #13
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Re: fore and aft trim

If this was a one-design boat it may have been required by class rules. For example, in J 105s the hulls built prior to the rosen-infusion SCRIMP process must carry weight since their hulls are lighter than the more recent hulls.

Many measured hulls for handicap formulas such as IRC will have waterline marks painted to the hulls by the official measurer. When those boats show up at a race, they must be on their lines. Sometimes weights are used to insure this. Those weights might then be removed for other handicap systems, such as when the boat races PHRF rather than IRC.

Tell us what the boat is, and we might be able to tell you exactly how those weights function. Some classes have rules that cruisers wouldn't normally guess at. For example, I used to race Santana 22s in one-design. S22 class rules stipulate that if you'd removed the head, you had to carry an extra ten pounds. Most serious racers did this, since ten pounds stored at the keel bolts was an advantage over a ten-pound toilet in the bow.

Or, check for yourself to see whether there's a little white line on the bow at the waterline. That would be a dead giveaway.
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Old 07-12-2012, 10:48   #14
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Re: fore and aft trim

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For example, in J 105s the hulls built prior to the rosen-infusion SCRIMP process must carry weight since their hulls are lighter than the more recent hulls.
Resin infusion made the hulls heavier?
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Old 07-12-2012, 12:04   #15
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Re: fore and aft trim

It is never good to put weight in the ends of a boat. Weight way forward and aft causes the boat to hobby horse in a seaway and the bow to plow through waves. Sometimes you have to do it like with chain rode but it's to be avoided if possible.

If the boat is the typical flat bottomed, fat assed newer design, the ingots won't be doing much for stability. They were probably added for fore and aft trim, the question is why?? Was it to counteract crew weight, get a rating advantage, meet class requirements, etc?? If that's the case, best to get the boat loaded for cruising and then subtract or even add more ballast to trim the boat on her lines. I'd try and get rid of the ingots rather than making them permanent. Unnecessary weight effects performance negatively.
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