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Jeff Jeff is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 1,301
Default Google proves MacGregor 26 is flimsy

JimC wrote:
And the other issue is that the water ballast extends all the way
from stem to stern. This can't be helping the pitching moment at all.


Wrong again. it extends about 2/3rds, and the front and rear portions
of the tank taper to sharp end portions and are therefore of little
mass and no real consequence re the distribution of mass.

Not according to the published diagram:
http://www.macgregor26.com/drawings/drawings.htm

Its pretty clear from this that the ballast extends all the way
forward, and that in fact a substantial amount is forward of the
mast. You should really spend some time learning about your boat, Jim.


Jeff, did you happen to take courses in geometry and logic in high
school or junior high? The reason I ask is that you obviously know
nothing about either subject.


Actually, I majored in Naval Architecture for two years before
switching to Physics. Then I worked for NASA for 6 years. Any more
questions?

- The fact that the water ballast tank in
the Mac extends toward the bow, forward of the mast, is not
determinative of whether it extends about 2/3rd the length of the boat.


It starts at the bow, and it ends at the stern. The diagram clearly
shows the water ballast running the entire length of the boat. If
anything, it looks that the tanks is deepest in the forward area. The
cross-section at the forward station under the hatch appears to be
by far the largest, indicting that a large portion of the water
ballast is forward.

Here's the diagram again:
http://www.macgregor26.com/drawings/drawings.htm
please tell us if there's any other way to interpret this?

And with a 250 pound engine hanging of the stern, that's a lot of mass
in the extremities.


(Remember that my statement was in response to Scotty's ridiculous
remark that the water ballast extends "all the way from stem to stern."
- Why didn't you criticize Scotty for making such a stupid remark?)


Because I made it. And is what is your problem with it? Are you
claiming that the diagram on the Mac site is faulty, that the tank
does not run the entire length? Or are you arguing on the meaning of
"stem to stern"?

Also, the ballast tank is tapered at the front and back such that the
volume (and mass) of water held at the front and rear portions is
substantially less then that held toward amidships.


Clearly, there seems to be little ballast in the stern, but with the
heavy engine, plus the possibility of a full cockpit, its probably not
possible. However, the largest cross-section of the tank is shown at
the station halfway between the keel and the bow at the waterline.

While the bow obviously "tapers in" (yes indeed, they did make the bow
at the pointy end) which means the ballast must be reduced in the
forward few feet, but so is the buoyancy.

Additionally, the
heavier, permanent ballast is positioned amidships, below the mast.


Just where ballast should be. Good for them.


Jeff, I've sailed many boats. The Mac 26M doesn't pitch excessively and
doesn't pitch more than most others. (Have you sailed the 26M? - No?)


I'd love to, but most of the Mac owners hardly ever go out. I have
sailed by them a number of times and they do seem to bob around more
than heavier boats.

Seems to me that this is just one more example of the fact that the most
opinionated, inflexible critics of the Mac 26m are those who have never
sailed one.


From everything you've posted Jim, there's no evidence you've ever
been on one either.