This is a really interesting suggestion.

I have had a number of compatriots at sea that did not not wotking on
tankers. Tankers are Very Stable. So, they come upright very fast and
hard. Passenger vessels are the opposite, the reason the roll is slow
(and more confortable to some) is that they have little righting force
and so return to upright slowly and gently. Down side is the ship's
crew must be very aware of the G.M. on a continues basis.

Without an accruate table of the weight and moment that you are adding
and the full set of LD curves for that hull, you have no way to know how
much ballast you will end up needing.

If the hull still has its tags, It will tell you interesting numbers,
but you probably do not want to set it down to its maximum load waterline.

Decide what draft you want to have, and mark the hull there, have as
many of your friends there as you can when you launch, and have them get
on until you are near the marks. Tally the weight as they get off.

Good Luck Guy

Matt Colie A.Sloop "Bonne Ide'e" S2-7.9 #1
Lifelong Waterman, Licensed Mariner and Pathological Sailor


P.C. wrote:
Hi

"ingmar" skrev i en meddelelse
om...

Hello Group,

has anyone out there converted an old lifeboat into something like a
'Canal Boat'? I am working with a 26 foot aluminium hull. Presently
building a cabin to make it so i can spend some time on the boat, with
berths and cooking facilities etc. I have an older 18 horse Yanmar
diesel to install. I understand that I will need some ballast to keep
the boat from bobbing like a cork. Question: what kind of ballast?
Cement? and how much? Thanks in advance! Ingmar


What you realy must consider, is the hull ability to stop rolling.
As if you place all ballast ,so it kind of keep rolling from one side to
another like a pendul in a clock, -------- no great idea most often caused
by all the ballast placed at the bottom in the middle of the boat.
Best way to avoid this, is to divide the ballast in 3 ; one third at the low
bottom, and each orher third as near the waterline and as far "out" , each
side of the hull.
The reullt is, that the parts of the ballast at the waterline will move
up-down and not make the hull swing from side to side whenever rolled.
P.C.

With boats like that, you must emagine how