Positioning Ballast for Stability

[Keeping Up]

Well, I did start by saying I was talking about the amount the boat rocks from side to side as the crew member walks through the boat, and later added "The plating is effectively from baseplate to waterline, hence its CoG will be exactly halfway between the two (ie just under a foot above the base). I would have expected the boat's COG to be higher than that. The baseplate weighs just over 5 tons and the overall loaded weight must be around 20 tons" which covers the known dimensions and weights. Ok I should have been explicit that it was a narrow boat; the plating was done a few years ago which is how I have been able to sense that the boat seems to rock more - and yes I do love the boat which is why I had it overplated.

[ditchcrawler]

1 hour ago, Keeping Up said:

Well, I did start by saying I was talking about the amount the boat rocks from side to side as the crew member walks through the boat, and later added "The plating is effectively from baseplate to waterline, hence its CoG will be exactly halfway between the two (ie just under a foot above the base). I would have expected the boat's COG to be higher than that. The baseplate weighs just over 5 tons and the overall loaded weight must be around 20 tons" which covers the known dimensions and weights. Ok I should have been explicit that it was a narrow boat; the plating was done a few years ago which is how I have been able to sense that the boat seems to rock more - and yes I do love the boat which is why I had it overplated.

But we all forgot where it started

[WotEver]

28 minutes ago, ditchcrawler said:

But we all forgot where it started

Do I know you, young man?

[howardang]

24 minutes ago, ditchcrawler said:

But we all forgot where it started

...and the bottom line is - suck it and see. At least it started the usual protracted discussion which, if nothing else, helped to pass the time  and gave the "experts" a chance to demonstrate their  knowledge, (and indeed qualifications!)

 

Howard

[WotEver]

Just now, howardang said:

...and the bottom line is - suck it and see. At least it started the usual protracted discussion which, if nothing else, helped to pass the time  and gave the "experts" a chance to demonstrate their  knowledge, (and indeed qualifications!)

It was a fun diversion.  What should we argue about discuss now?

 

I know... which uses the most water in a flight of locks - a wide beam or a narrowboat?

[Murflynn]

6 minutes ago, howardang said:

...and the bottom line is - suck it and see. At least it started the usual protracted discussion which, if nothing else, helped to pass the time  and gave the "experts" a chance to demonstrate their  knowledge, (and indeed qualifications!)

 

Howard

fair comment  

 

 

as has been said - suck it and see.      there are many physical situations that can be over-analysed, this is certainly one of those.

[TheBiscuits]

6 minutes ago, WotEver said:

It was a fun diversion.  What should we argue about discuss now?

 

I know... which uses the most water in a flight of locks - a wide beam or a narrowboat?

 

How deep is the lock, and is it a tiller steered widebeam?

 

 

 

[WotEver]

1 minute ago, TheBiscuits said:

 

How deep is the lock, and is it a tiller steered widebeam?

Now you see... these are the kind of questions that nobody thought to ask the last time...

[Keeping Up]

But it could have had a positive outcome, if I knew for certain whether to blame the rolling on SWMBO's weight or not. For some reason she seems to get upset when I tell her it's her fault!

[Alan de Enfield]

Timely discussions in Augusts  Practical Boat Owner magazine.

 

Get some weights low down and as wide as possible.

 

Edited June 10, 2020 by Alan de Enfield

[TNLI]

Anyone know how much ballast they have in their pride and joy ??

 

My sunken wreck of a lifeboat has a fairly flat bottom and is double ended like most canal boats, but the old wet sand bags were not exactly factory fit, so if anyone has their total ballast weight, along with LOA, I would be interested. 

 

My boat is 27ft LOA, 9ft beam and 3ft 6in draught.