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KEEL


BJ

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Well, Ray seems to have made his point quite well. If it helps, and it's done right and seems to be standing up to use, why not? I do know these boats are helped by a bit of weight, and we used to keep our batteries forward for that very reason, but a part of me can't let go of the No Ballast concept.

I think these are really good evolutionary steps in the development of these boats. Cool work!

Mike

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I have refrained from posting on this thread, in fear it would generate the classic ballast/no ballast debate, that has raged on this and other sites before.

There have been successes, though I don't think 4 years is enough, to call the jury in, on Ray's particular application. His requirements needed the trim, a considerable amount of it. It should be recognized that each build, the owner's skills, habits, sailing ability, loading, sailing locations, crew and stores compliment will require a different approach. No one arrangement will suit another without considerable adjustment.

For this reason, installing fixed ballast, before extensive sailing trials isn't a wise option, for the extreme majority of Weekender/Vacationer builders. You don't know what you need, nor where you need it until you have practical experience sailing the boat in a variety of conditions.

I have conducted considerable analyses of the Vacationer and subsequently the Weekender. The Vacationer studies were to insure my changes, to Jim Sanders already heavily modified Vacationer, would hit very close to the right balance at launch. The Weekender came at the request of others, including a client of mine, who is now sealing up the sides and readying for sheathing on his Weekender.

The location of ballast isn't an easy thing on paper or computer screen without proper tools and education. From a practical nature, it's much easier and a better way to refine location, with the boat in sailing trim and having seen considerable use. Moving a cooler (full of beer of course) fore and aft in the cockpit or cabin, will very quickly determine the proper spot the boat likes best.

From a technical stand point you're not gaining anything by ballasting Weekender, in fact you are loosing some of the righting ability of the vessel, plus diminishing its load carrying capacity. What you do get is deeper immersion of its underwater areas, which slows the boat down in every regard - turning, acceleration, helm response, weather helm (which increases slightly), pointing ability, eddy making, frictional resistance, etc. This doesn't mean you shouldn't ballast Weekender, but it does mean you should weigh the pro and con about this issue carefully. I'm personally of the same opinion the designer is and no ballast is necessary on a 13' LWL, low aspect, shoal draft skiff, like this boat (it's not a dory, not even close).

This hull shape relies on form stability to provide it's righting ability, plus the advantage of "live" ballast in the likes of crew hiking out, to keep her reasonable flat footed underway (which is what she likes best). The CG is so close to the CB that any weight, even placed as low as physically possible on the keel bottom, just doesn't provide enough separation to be effective. The end result is at modest angles of heel these two centers invert their relationship and the stability of the craft is compromised, not increased. A stability curve for Weekender stock, compared to 300 pounds on her cabin sole isn't particularly interesting. The same curve and a single crew member (160 pounds) with their butt planted on the side deck, in an upright and comfortable seated position is very interesting and dramatically increases the right arm available to the craft.

This is very typical of small boats. Ballast is necessary when hull volume exceeds the material, equipment, stores and crew weights, or when you wish for a high SA/D ratio for performance reasons. Currently, Weekender carries 868 pounds of displacement in cruising trim, which is as observed, the point of the bottom planking forward, just kissing the water and the transom with an inch of emersion. Typically this would include a battery, crew around 300 pounds and odd bits and pieces. Add an outboard, fuel tank, cooler (full of beer), radio, another battery and more bits and pieces and you've quickly lowered the boat another inch (which requires 1,065 pounds) and the point of the bottom planking is now about an inch in the water and the transom well buried (2"). Add a couple of fat guys an extra cooler full of beer and you get another inch of immersion (1,266 pounds), which places the transom 3" down and the bow 2".

What do all these numbers mean? That she can handle a lot of weight.. At 3/4 of a ton in displacement, she is a wallowing tub which is in danger of flooding from a stern wave or very modest angles of heel over the sidedecks. Remember the photo of the blue Weekender with four aboard and the tiller hole almost awash? Clearly that "ballast" was placed too far aft, but a good indication of what weight does to a 13' LWL boat.

Point? Sure, add 300 pounds to a Weekender and you've basically added two invisible crew members, which can't lean to windward and limit what you can carry or the angles of heel she can tolerate.

Ray's situation was unique and I understand it. His crew weight is higher then most, his sailing locations rougher then most (plus other variables), so ballast was a compromise that worked for him. Each builder has to access this set of variables and offset the trade offs, independently.

Wholesale acceptance of this ballast idea isn't wise, the designer doesn't recommend it, I don't either, but ultimately the individual builders will have this decision. If you'd like to see some calculations for both Weekender and Vacationer, including stability curves in different configurations, then drop me an email.

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I've always understood Ray to qualify these types of changes, as well as any others that influence the underwater areas of the boat, with a reasonable length of unaltered sailing time in the boat.

This aside, you can't compare apples to oranges. The Haven 12 1/2 and Weekender have very little in common. They are as dissimilar as a dump truck is to a motorcycle. Comparing the two in any regard is silly, except that they both have sails and one end is pointier then the other. They aren't remotely close to each other, from a design concept/principals incorporated point of view. For what it's worth the 12 1/2 has likely 10 times the lateral area of a Weekender, which is the basic problem with both Weekender and Vacationer.

Steering complaints, excessive skidding to leeward, inability to tack in certain conditions, initial tenderness, excessive heel, etc., are the common points raised about these designs.

Do you think the inability of the appendage, to generate lift underway, or provide lateral resistance to offset it's sail area or momentum, has anything to do with it? Can you think of any shoal draft craft, with an appendage even somewhat similar to the one used in these two boats? I have thousands of designs on file, none exhibit such little area, or such a shallow profile (without a board of some sort) or place the bulk of area forward instead of aft.

It must be that Mr. Stevenson has developed a revolutionary appendage, which no one seems to have caught on to, in the 30 years since it's inception. Being the student of design history, which I've become in recent years, I can assure you that any idea worth having a look at, has been mimicked repeatedly, usually before the patent application envelope, postage stamp adhesive has complete dried.

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I suspected we were in basic agreement, Ray. Adding 250 pounds or so to a Weekender is half a full load, which will drop her down enough to keep her from being quite so jittery. Joel White's Haven is a much larger craft, one look at it's 22 steam bent frames will confirm this, without needing to see displacement figures. Her immersed volume is nearly twice that of a Weekender, so 300 pounds to her is like 150 to a Weekender.

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So am I anywhere near correct in inferring that the two most studious of our ballast thinkers are pretty much in agreement that sailing methods and experience (helm-time, rather than stick-time, I guess?) are preferable to worrying about ballast too early in one's Weekender or Vacationer building process? The addition of ballast (which, by the way, we actually do ourselves in the form of internal ballast batteries for the motor) is something best understood through a bit of familiarity?

It'd be nice to come to a bit of an amicable mellowness about the whole issue. It certainly flared up in the past, and I'm glad it seems to have sorted out to a broad consensus (kind of.?.?.)

Mike

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Neat! You had a chance to really feel out how you liked the improvements. Peter and I just are chatting about this (he's out here in Carmel for a couple days visiting) and he was restating how much he would vary the weight carried depending on the day's conditions. This works great in SoCal, where the day is almost always going to be a certain way all day: no surprises in weather most of the time. Having spent a bit of time in Texas this Spring and seen just how fast conditions could change (and I assume it's similar across the central states), I'd be more inclined to have what I needed on hand. It'd be a shame to have the batteries in the car when it suddenly got blustery.

A good thread, I think.

Mike

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