BoatBanter.com - Hull Flexing

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Nope... no soldiers as far as I know... and why would they be watching my
buttocks? [Marines?]

Now what pray tell has changed about my recent posts? Have I not always
sought to be equally obnoxious to all of you? Have I not tried to make
certain each of you is given their due attention?

Has it become so difficult for you to follow a simple thread that you find
it impossible to comprehend that when someone on a sailing group asks
"what's your point" and you answer 32 degree it might relate to the heading
of your vessel? You can't see the tie MC? Are you becoming so sensitive that
the slightest of jabs causes you to feel hurt?

....and since when have you allowed gentlemanly behaviour to interfere with a
good strike.

Go ahead MC..... point it out!! ;-)

Or is it that you can dish it out but you can't take it?

CM

"The_navigator©" wrote in message
...
| I though you were talking about the angle of the fan of soldiers lined
| up behind you watching your buttocks -given your recent posts. being a
| gentleman I chose not to point this out.
|
| Cheers MC
|
| Capt. Mooron wrote:
|
| Oh Yeah... that's right you always have the engine on so it's
irrelevant!
|
| CM
|
| "The_navigator©" wrote in message
| ...
| | ?
| |
| | Cheers MC
| |
| | Capt. Mooron wrote:
| |
| | Oh about 32 degrees in a pinch... You?
| |
| | CM
| |
| | "The_navigator©" wrote in message
| | ...
| | | What's your point?
| | |
| | | Cheers MC
| | |
| | | Capt. Mooron wrote:
| | |
| | | How does that differ to her usual condition of standing by
outside a
| | harbour
| | | with a fouled prop?
| | |
| | | CM
| | |
| | | "The_navigator©" wrote in message
| | | ...
| | | | I'd say It's BS because boats are simply not that rigid and
it's
| hard
| | to
| | | | measure to an accuracy of 4 thou on big objects. The
flexability
| of
| | most
| | | | boats is such that the side stays limit the spread of the
hull
| as
| | the
| | | | backstay is tightened (this is naval architecture 101).
Current
| rig
| | | | tensions are much higher than they used to be. Even Ella has a
| | backstay
| | | | tension of 2,500 lbs when beating.
| | | |
| | | | Cheers MC
| | | |
| | | | DSK wrote:
| | | |
| | | | The_navigator© wrote:
| | | |
| | | | 4 thou. measured on the back of a boat? Complete BS.
| | | |
| | | |
| | | | "The Captain...cap n all" wrote:
| | | | I would have thought so.
| | | |
| | | |
| | | | AFAIK there was no reason to BS about it, the boat was a
one-off
| | | | and paid for. If I am interpreting the article about the
boat
| | | | correctly, the distortion was measured at the mid length
along a
| | | | straight from stem to center transom.
| | | |
| | | | If one is installing high powered hydraulics to control the
rig,
| | | | it makes sense to make the hull & deck structure as rigid as
| | | | possible, within reasonable weight limits. I haven't seen
any
| | | | figures for the distortion measured on the newest IACC boats
but
| | | | the early 1990s boats had very high rig loads (10K kg and
up)
| | | | and very little (if any) distortion.
| | | |
| | | | Fresh Breezes- Doug King
| | | |
| | | |
| | | |
| | |
| | |
| | |
| |
| |
| |
|
|
|

Yeah.. I admit that.... but cripes I had to explain it to MC!!!

That would make it really really bad!

CM

"DSK" wrote in message
...
| "Capt. Mooron" wrote:
|
| Oh about 32 degrees in a pinch... You?
|
| Bad pun.... bad bad bad!
|
| DSK
|

It's like this. We were talking about the military. In fact there have
been more posts about the military than sailing recently so I just
posted a "?" because the context was not clear. Was that wrong of me?
Now, I assumed they would be looking at your ass because you would be
point -being a hero and all. Perhaps I think too laterally for you. I
will try to limit myself to your level in future, I promise.

Cheers MC

Capt. Mooron wrote:

Nope... no soldiers as far as I know... and why would they be watching my
buttocks? [Marines?]

Now what pray tell has changed about my recent posts? Have I not always
sought to be equally obnoxious to all of you? Have I not tried to make
certain each of you is given their due attention?

Has it become so difficult for you to follow a simple thread that you find
it impossible to comprehend that when someone on a sailing group asks
"what's your point" and you answer 32 degree it might relate to the heading
of your vessel? You can't see the tie MC? Are you becoming so sensitive that
the slightest of jabs causes you to feel hurt?

...and since when have you allowed gentlemanly behaviour to interfere with a
good strike.

Go ahead MC..... point it out!! ;-)

Or is it that you can dish it out but you can't take it?

CM

"The_navigator©" wrote in message
...
| I though you were talking about the angle of the fan of soldiers lined
| up behind you watching your buttocks -given your recent posts. being a
| gentleman I chose not to point this out.
|
| Cheers MC
|
| Capt. Mooron wrote:
|
| Oh Yeah... that's right you always have the engine on so it's
irrelevant!
|
| CM
|
| "The_navigator©" wrote in message
| ...
| | ?
| |
| | Cheers MC
| |
| | Capt. Mooron wrote:
| |
| | Oh about 32 degrees in a pinch... You?
| |
| | CM
| |
| | "The_navigator©" wrote in message
| | ...
| | | What's your point?
| | |
| | | Cheers MC
| | |
| | | Capt. Mooron wrote:
| | |
| | | How does that differ to her usual condition of standing by
outside a
| | harbour
| | | with a fouled prop?
| | |
| | | CM
| | |
| | | "The_navigator©" wrote in message
| | | ...
| | | | I'd say It's BS because boats are simply not that rigid and
it's
| hard
| | to
| | | | measure to an accuracy of 4 thou on big objects. The
flexability
| of
| | most
| | | | boats is such that the side stays limit the spread of the
hull
| as
| | the
| | | | backstay is tightened (this is naval architecture 101).
Current
| rig
| | | | tensions are much higher than they used to be. Even Ella has a
| | backstay
| | | | tension of 2,500 lbs when beating.
| | | |
| | | | Cheers MC
| | | |
| | | | DSK wrote:
| | | |
| | | | The_navigator© wrote:
| | | |
| | | | 4 thou. measured on the back of a boat? Complete BS.
| | | |
| | | |
| | | | "The Captain...cap n all" wrote:
| | | | I would have thought so.
| | | |
| | | |
| | | | AFAIK there was no reason to BS about it, the boat was a
one-off
| | | | and paid for. If I am interpreting the article about the
boat
| | | | correctly, the distortion was measured at the mid length
along a
| | | | straight from stem to center transom.
| | | |
| | | | If one is installing high powered hydraulics to control the
rig,
| | | | it makes sense to make the hull & deck structure as rigid as
| | | | possible, within reasonable weight limits. I haven't seen
any
| | | | figures for the distortion measured on the newest IACC boats
but
| | | | the early 1990s boats had very high rig loads (10K kg and
up)
| | | | and very little (if any) distortion.
| | | |
| | | | Fresh Breezes- Doug King
| | | |
| | | |
| | | |
| | |
| | |
| | |
| |
| |
| |
|
|
|

Why not 552?

Cheers MC

Capetanios Oz wrote:

On Thu, 13 Nov 2003 12:38:12 +1300, The_navigator©
wrote:

Sikaflex.

Cheers MC

292.

Oz1...of the 3 twins.

I welcome you to crackerbox palace,We've been expecting you.

"Flying Tadpole" wrote in message
...
You mean, you want a heroic ode, based on the poor elephant seal,
cumbersome and easily attacked by vicious sealers on land, speedy
and graceful on/in the water, but nevertheless doomed by its
liberal outlook and engineering limitations?

Yes please!

Regards

Donal
--

"Capt. Mooron" wrote in message
...

Now what pray tell has changed about my recent posts? Have I not always
sought to be equally obnoxious to all of you?

You have never been obnoxious.

Have I not tried to make
certain each of you is given their due affection?

Yes!

Let's face it, Mooron. You are a really nice, Canadian, sort of guy. You
couldn't be obnoxious if you tried!

You've got the vocabluary, but not the nationility. I used to believe that
you were Belgian, especially when you said that you were allergic to soap.
However, I'm rapidly coming to the conclusion that you use Imperial Leather
when you take a long bath -every day.

Regards

Donal
--

I thought 552 was recommended for Al.

Cheers MC

Capetanios Oz wrote:

On Thu, 13 Nov 2003 13:02:12 +1300, The_navigator©
wrote:

Why not 552?

Cheers MC

Good question.
292 was recommended by the rep.
IIRC they are both about the same afa strength goes.

Oz1...of the 3 twins.

I welcome you to crackerbox palace,We've been expecting you.

In article , DSK
wrote:

Peter Wiley wrote:

Completely & utterly impossible to say without knowing design &
construction details and doing some sort of finite element analysis
which is way beyond my technical competence. That'd only give you a
theoretical measurement anyway.

But it is possible (not that difficult) to measure the hull's deflection
along any
axis in the real world. Not everybody has a dial indicator handy, though.

I agree completely. What I meant by saying you'd only get a theoretical
measurement. As a machinist I keep DTI's that measure to tenth's about,
of course. Hell, I've just been using a cheap laser level to level
formwork for a concrete slab I'm about to pour. When I finished, the
formwork was level to plus/minus 3mm all round, or 0.120". Today it'll
be something else, no doubt. We've used surveying gear to locate 3D GPS
antennae on ships to better accuracies. Isn't rocket science.

Think about it for 5 seconds, Nav. How thick is the plating? How many
longitudinals and frames and what spacing? How many welds and at what
spacing? What sort of keel? Is the deck a different material or not? Is
the shell monococque or not? Etc etc. Steel (I know little about ferro)
boats are typically a monococque construction with steel decks attached
to the hull by welding. Plastic boats may have their decks 'glassed to
the hull but usually it's a handful of self-tappers and a tube of
sikaflex. No rigidity there.

I disagree. Most structures are essentially the same, a box girder. Steel is
surprisingly limp all by itself. That's why they make I-beams instead of just
steel
planks.

True.

You're right that the details of the hull-deck joint are important to the
boats
structure. A lot of mass-produced boats do not have a very good hull deck
joint,
but others do. It is not inherent in the material.

Also true but I thought that's what I said - some plastic boats have
decks glassed to hull and this is damn strong, minimises possible
movement & flex (not to mention leaks.....) Those put together with pop
rivets or self-tappers have a lot more potential to flex.

I do know that some steel boats can be easily lifted by a couple of
eyebolts welded internally without any worries about deformation

So can many fiberglass boats. But this wasn't really an argument about the
relative
merits of steel vs fiberglass, was it?

Nope. Different materials, different strengths/weaknesses. Ditto ferro.
Friend just bought a 38' ferro sloop in really good shape for $30K AUD.
He knows the resale value is going to be the same - crap - but it's a
lot of boat for the money and for him it's a good choice. As he says,
if he gets 10 years out of it that works out to $3K pa even if he can't
sell it at all after that. Still worth it.

Peter Wiley

In article , Flying Tadpole
wrote:

Peter Wiley wrote:

snip

The issue isn't repeatability at all. You're merely trying to shift
goalposts. Your Ella is a racing boat and built like one - minimum
weight and what you see WRT flexing is what you'd expect. As a class
they break in really bad weather because they're outside their design
envelope.

Was it so bad a voyage/tour of duty, Peter, that even on your
return you insist on clubbing insensible elephant seals?

Was a good voyage actually. Hobart to the ice edge, into the pack for a
few weeks, across to Casey base through the pack and then back out and
home. Drop me a line and I'll send you some pix.

I don't have any problems with people owning lightweight plastic boats
- they do go fast and point high, plus you get lots of exercise
changing headsails with each 5 knot wind change. Just that nobody
should think they're good for much else.

Be nice to see a light schooner on the Derwent.

Peter Wiley