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[El Neave]

Right, Perekasaman, and very especially so given the top hamper Tico's carry.  What I retain from a mind widening discussion is to put as much weight on the bottom at the point where the hull goes vertical; even, as was suggested by
Colin, to a point that waterline level is slightly above the marked waterline in an effort to reduce rolling or at the very least to ensure that the Quiberon Bay does not suddenly take on all the characteristics of a U Boat!

That the erudite are now turning to Active Ballasting, is like as not to add to the number of grey hairs.  I shall follow this with attention, none closer, But whatever the outocme, it will have to be for the next build.

Gentleman and scholar, hey!!?? I shall turn the other cheek.  The last time I lived in UK, only the drinkers of Carling Black Label; I think it was, could make the slightest claim to such distinction.  Scholarship?  I' m not sure,
though I do scribble from time to time;  Let's call it, obscure meanderings.

To help these irrelevances go down the gullet easier, here)s another pic of the QB,

Best,
El Neave.

[geoff p]

Years ago I worked for the Shetland Islands Council and had to do some work with the Fair Isle ferry.  She had been converted from a fishing boat by adding a few tons of concrete ballast (and a bit of passenger accommodation).  This replaced to weight of fishing gear, which had of course been removed.

She bobbed like a cork!

So the concrete ballast was removed from the bilges and its mass replaced with a concrete bulkhead - effectively a huge flywheel.

Now she would roll but very sedately, then gently (for her) roll back to upright (sort-of).  She was still a pig in the for-and-aft (pitching) axis.

Geoff

[gingyer]

The QB looks good there

[astrophe]

Hi,

What you are referring to are changes in 'moments of inertia'. 

The effect is the same as a seesaw.  If you both sit at the ends it is hard to make it rock quickly.  If you both sit together over the pivot, it is easy.

As a sailing man, we have to consider whether to put heavy things, such as the anchor and chain right at one end , close to the bows, and the crew right at the other.  Same weight but high moments of inertia.This makes the boat resistent to pitching so gives a smoother ride as you cut through the waves but makes a lot of water come over the boat (uncomfortable for the crew).

Or: Place heavy items close to the centre of the boat which mekes her ride easily over the waves but makes the boat pitch badly.  This is uncomfortable for the crew (but it is their career choice) but worse; shakes the wind out of the sails.

Over the waves or through them?

Hope this helps

Cheers, Andrew.

[NormanB]

Of course for the really academically curious with lots of time you can always conduct an inclining experiment which will enable you to establish CofG, Metacentric Height, Centre of Buoyancy and crucially the righting lever (GZ sin O/ ) (theta).

[deadbeat]

An inclining experiment - that takes me back, I was on one after the special refit of HMS Ashanti in Pompey dockyard. It was to be conducted in Basin 3 on a Saturday, but the wind was too high, and as HMY Britannia was alongside in Basin 3 and held off from damaging paintwork by wires right across basin 3 they refused to drop the wires to let Ashanti into the Basin. So it was postponed to the Sunday, as an apprentice it was the only Sunday I did!

[emspaul]

I have one of these, and I can say she looks great.
The type of weights I used for this ship are the sticky weights they use on Aluminum car rims.
Make sure that you secure your battery in the hull,as I have had the gray hairs pop out when it slid to one side.
I lost the SH 60 over board when this happened.
The wind was a little over 10 knots .
Keep her close to shore when it is that windy .
Keep up the great work.