>
> My turn to snap........................
>
> My priorities are MINE and I really don't care if I am the only person
> in the world who thinks they make sense.
Okay
>
> I have no desire whatsoever to "go fast" that is why I bought a boat to
> potter in.
Okay
>
> Though I like the boat, and think it looks as cute as hell, I am open
> minded enough to point out that "the King has no clothes", the Potter
> HAS deficiencies, one of them being it is very tender, not being much
> different than a wooden centerboard dinghy, and I fail to see the
> advantage of a hard chine apart from allowing construction out of
> plywood. No boat designer in his/her right mind would set out designing
> a boat (that was to be made of fiberglass) with a hard chine.
That last remark puts you at odds with most of the powerboat manufacturers on
the planet. Those hard chines are a big part of the initial stability which
folks like in the Potter. That shape means as the boat heels the center of
buoyancy moves outboard very quickly. As you have experienced better than
most of us, payback time comes when you need ultimate stability - Those
nearly vertical, flat sides do not offer much reserve buoyancy as the boat
heels further.
>
> The only value of a boat being light is that it is easier to trailer,
> but I fail to see that an extra 200# is going to substantially affect
> gas mileage. As to the increase in difficulty of launching and
> retrieval, I feel I am wallowing in power using a Nissan Sentra. I used
> to launch and retrieve my Ensenada 20 with a VW Beetle! Boat and
> trailer weighed 2000#.
Agreed on the gas mileage. Under sail, increasing the boats weight by almost
50% probably won't go unnoticed. Slower response to the helm, less
accelleration in puffs, and a boat that want to wallow through chop rather
than go over it.
I'd like to hear more about the Ensenada 20 - those boats have some very
devoted followers. I don't know that I've ever seen one....
>
> Regarding the benefits of fixed ballast with respect to roll stability,
> even elementary analysis shows a marked benefit due to the rapid shift
> in the position of the center of buoyancy. Very rough calculations
> together with best guess estimates of the position of center of buoyancy
> at various angles of heel show (as might be expected) a substantial
> increase in ultimate stability, but also a surprisingly rapid and
> increasing addition to early stability. Fixed ballast has the added
> beauty of being there WHEN IT IS MOST NEEDED (i.e. at 90 degrees) as
> opposed to intelligent ballast, which ballast along with all it's
> intelligence, has by this time been dumped unceremoniously into the
> water. (Same ballast, after the boat having reached a substantial angle
> angle of heel, intelligently fell to the opposite side of the cockpit
> and actively aided the overturning moment). Said fixed ballast would
> certainly be an asset should the boat turn turtle.
> One has to assume that anyone proposing to add fixed ballast to a boat
> such as the Potter has enough sense to FIX it.
> On the matter of the boat going slower, what is the difference between
> 200# of ballast and a 200# passenger? Apart from the fact that a
> passenger takes up a lot more room and gets in the way a lot? I suggest
> that more energy is needed to power a boat with 300# (say two people) of
> passengers than with 200# of ballast.
We must be picturing things differently - help me understand what you are
thinking. What I see, if weight is added in the bilges inside the hull, is a
center of mass not more than 12 inches away from the center of buoyancy when
the boat is on it's side. That's only 200 ft.lbs. of righting moment, and
less than the boat had at 45 degrees. For more righting moment at knockdown
adding a smaller mass near the bottom of the centerboard would be just as
effective and would make for a more favorably shaped stability diagram. How
about a fiberglass skinned (no rust), foil shaped (better windward
performance), lead filled (nice and dense) replacement centerboard? Your
point about "smart" ballast being tossed around/overboard is valid. I do
think that a knocked down Potter with it's CB secured in the down position
should recover once it's "free" of it's "parasites".
>
> Finished snapping, but still feeling cranky.
Must be something in the air, I'm still cranky too - Pity the poor co-workers
for they know not why........
>
> Regards (I think), Bernie Johnson
Best regards (quite sure)
Dave Kautz