On Thu, 03 Jul 2008 22:27:51 -0400, Matt Colie
wrote:

Every boat has the center of gravity above the center of buoyancy.

Why? Ever hear of heavy ballast keels? If the superstructure is heavy
that's one thing, but it doesn't have to be.

Casady

"Roger Long" wrote
The mini houseboat fellow won't get very far trying to apply what he reads
about GM in a standard textbook to his problem.

My guess from the OP's photo is that he has a tri-hull, of typical heavy
60s-style construction. If he goes through with his hard-top plan, I'm
thinking he'll end up with something akin to a pontoon boat.

On Jul 4, 12:22*pm, "Ernest Scribbler"
wrote:
"Roger Long" wrote

The mini houseboat fellow won't get very far trying to apply what he reads
about GM in a standard textbook to his problem.

My guess from the OP's photo is that he has a tri-hull, of typical heavy
60s-style construction. If he goes through with his hard-top plan, I'm
thinking he'll end up with something akin to a pontoon boat.

Here is a neat program that will give you some pretty basic ideas of
rightingmoments, bouyancy, trim, etc..

http://carlsondesign.com/#Fun_Shareware

It's shareware, but for a quick idea of a design and it's capability,
it is ok..

On Jul 4, 7:52*am, wrote:
...
Well, at the risk of being simple. I still suggest it's the wrong boat
for the job. He just needs to start with the right boat. He can
justify, defend, and make any excuses he wants.. Still water,
whatever.. But once you leave the dock, things can change quickly to
something you have never seen before.
Anyway. Have a great fourth, go out in your boats for me Scotty

It wouldn't surprise me in the least to find that the boat was
originally sold in several configurations (eg. bow rider, 1/3 decked,
cuddy cruiser, etc.). So, if the guy wants to convert from one to the
other and enjoys doing the work the hull might well be adequate.
Since we've only got a pic of the deck it is a little hard to tell
what the hull form is, but given the bluff bow I'm guessing it's a
Whaler style. If so, he's got oodles of stability. In Hawaii many
small fishing boats have home built hard dodgers very like lobster
boat style cabins. They put them on to get some cover when operating
at sea and stability isn't typically an issue at all. If I were
making this kind of conversion I'd put a little cuddy over the
foredeck, build a hard dodger and run some rails off of that aft to
use as supports for a Bimini, surfboard racks and tent. I'd probably
also put a proper transom on the boat and build an external rack for
the outboard. The cuddy and the transom will make the boat much less
susceptible to swamping the result may be more seaworthy than the
original. Sure he can do some testing to see if stability is going to
be an issue. I like Roger's method and if he can secure the table and
weights he can even go out and do some dynamic testing. But, in the
end, I'd be amazed if a well constructed cuddy cabin would make the
boat dangerously unstable.

Happy 4th!

-- Tom.

On 2008-07-03 11:34:39 -0400, David dh@. said:

I've got an old boat very much like this one:

http://www.warnersdock.com/images/Fr...fores15yel.JPG

that I'm trying to make into a mini-houseboat, sort of like a camper. I
only expect to have about 200-300 pounds in the roof and walls, and the
roof will only be about 48" above the gunwale. The hull will weigh a
*lot* more than what is added, so shouldn't that alone be enough to
keep it from being top heavy and flipping over? If I add weight, like a
couple hundred pound bags of sand down in the hull to counterballance,
shouldn't that take care of it? If so, should they be placed on the
sides, or in the center?

Judging from friends' boats of about that configuration, I'd suggest
something quite a bit lighter: a light hard roof and tarps, screen and
plastic for removable "walls", a pop-top camper of sorts.

That said, a friend was for a time a "slum landlord" of a number of
"floating structures" in Key West that were about what I hear you
saying. They (mostly) stayed afloat for some years and weathered some
nasty weather.

Have to say that the inhabitants were not thought well of, though, and
the "boats" uniformly disliked by all. Ugly doesn't begin to say it.

--
Jere Lull
Xan-à-Deux -- Tanzer 28 #4 out of Tolchester, MD
Xan's pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI trips & tips: http://homepage.mac.com/jerelull/BVI/

Gregory Hall wrote:
"David" dh@. wrote in message
...
I've got an old boat very much like this one:

http://www.warnersdock.com/images/Fr...fores15yel.JPG


snip

THIS is top-heavy:
http://images.thebiggestbreasts.com/...fake_boobs.jpg

Caution: nudity. Adults only please.

--
Gregory Hall



WAFA will spend all week on that one.