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snorinsid 12-15-2008 02:50 PM

Ballasting
 
My 1985 Hunter 25.5 is rather tender in anything beyond, perhaps, 15 knots of wind even for me, a veteran of many years of performance sailing. I know that this particular Hunter model was available in either an outboard engine version or a saildrive version. My questions are: 1. Is it logical to assume that the outboard version, which is the one I have, is underballasted in consequence of the absence of the typical weight of a saildrive of about 120 pounds? and 2. Would a couple of sandbags totaling 120 pounds in the bilge make a real difference in her ability to stand up to wind?

jbarros 12-15-2008 03:39 PM

I can't say whether or not they accounted for the change in weight distribution an outboard would cause (I certainly hope they did!) but even if they did, in my experience (all of 1 boat) even a little bit of ballast down low enough really does make a difference. I was able to get the extra ballast I put in my boat down into the (hollow) rear of the keel itself, but it did wonders.

Worst case scenario, try it out and see what happens. If you don't like it, you get, at worse, slightly slower sailing for a day, and you're out the cost of a few sandbags. :)

-- James

Boasun 12-15-2008 04:31 PM

Sand bags?? There use to be racing sail boats that used sand bags for ballast and the crew had to shift them every time they tacked.

Now we use human ballast sitting on the windward rail... :D :D :D At least they are smarter then the average sand bag. :D

Jeff_H 12-15-2008 04:49 PM

I would doubt that 120 lbs in sandbags will make much of a difference in stability. 120 lbs of low density ballast placed near the centerline of a boat like the Hunter would not noticably increase stability. My sense is that the Hunter 25.5 was probably designed to use a working jib in over 12 knots of and that you may be using too large a headsail for the conditions.

Jeff

sailboy21 12-15-2008 05:52 PM

I think there might be more inertial stability in the motor versions. Not much, but a little. Maybe a little more due to the engine acting as ballast. Smaller boats are very sensitive to weight. Also, keep in mind 120lbs might be on the light side. You should also include the weight of the added glass work for the engine bed & tank. Probably a lot more fuel capacity that you have for your OB. I would venture to say the two versions could very likely have slightly different sailing characteristics.

snorinsid 12-15-2008 06:10 PM

Re Ballasting
 
First, my thanks to those of you who responded so promptly. So far it's been constructive. You who added ballast down inside your ballast keel were lucky because the moment arm and, therefore, righting effect, are both greater. My Hunter with a draft of 4.5 feet has a solid, narrow cast iron keel with superficial rust (I sail in fresh water) so the sand bags will go atop it in the bilge. I also appreciate the guy who pointed out to me the added weight of engine mount, tank, etc for the saildrive; it suggests that perhaps 3 sandbags of 60 lbs would not be unreasonable. Next question: will 150-180 lbs of ballast materially slow down the boat? We race in season actively on the Hudson River.

seabreeze_97 12-16-2008 04:02 PM

Load 'er up!
 
A side-by-side test would show a slightly slower acceleration, particularly in light air, but we're talking slight, where the extra weight will help the boat stand up more against the wind, thus making her a bit faster and the main benefit, easier to handle. You didn't mention reefing, etc. Is that in play, and if so, to what degree?

snorinsid 12-16-2008 04:37 PM

Ballasting
 
Yes, we have a CD jib furler that works well and one reef point in the main with a fast reef line rigged to the cockpit. But when we're getting overpowered there is seldom enough time to reef; What I do is ease the main sheet so the boom rises a bit and we lose a bit of drive to windward. I know that 150 or so lbs of bilge ballasting will help. The real question is: will it be appreciable?

Sailormann 12-19-2008 01:34 PM

The degree to which it will affect the boat is largely dependent upon the boat's displacement. What is the designed displacement of the boat ? What is the ballast to displacement ratio ? Under 30% Over 40% ??? If you have a boat that weighs 10,000 pounds, of which 3 or 4000 pounds is ballast 150 pounds is going to make a difference but not a significant one.

The added weight means it will take the boat longer to pick up speed but it also means it will take the boat longer to slow down. Inertia being what it is ...

Good Luck :)

snorinsid 12-19-2008 07:31 PM

Ballasting: the numbers
 
The displacement of the Hunter 25.5 is 4500 lbs, keel weight is 1800 lbs, and draft is 4.5 ft. That suggests a ballast to weight ratio of 0.4, which sounds high to me at first glance. Do thesebers suggest significant heeling reduction with the addition of, say 150 lbs. in the bilge?


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