Donal wrote:

"The_navigator©" wrote in message
...


Jonathan Ganz wrote:


Well, I like Doug, so I won't comment.

Are you a coprophiliac or are you taken in by his endless BS?


I think that both you, and Doug, have a lot to offer.

Doug does seem to know quite a bit about boats. That shouldn't provoke an
emotional response.


He does know some things and when he's right, I'm not perverse and I
don't disagree with him. But on some technical issues -usually about
design and materials -he is wrong. When his mistaken ideas are presented
as a fact that may influence anothers action then I feel that one should
object to it. Of course one might say that this is an alt group and so
caveat emptor applies, I hope we sailors are far more responsible people
than most. For instance, suppose a newbie searched the archive and, as a
result of Dougs posting thought that a Bolger micro would be a safe boat
in a gale and did not seek protection early enough? The though of being
caught offshore in a vessel as unseaworthy as the micro should be an
anathema to any sailor unless they are suicidal. I say that it must be
made very clear that such boats are suitable for pottering around on
placid safe waters and nothing more. As such, they are probably great
fun and certainly cheap and easy to build. If that gets people sailing
then that's good too. But let's also remember that thousands of people
risk their lives and are rescued every year because they assumed that
their boats are up to any condition that they may find themselves in
when they are not -at least not with the level of expertise that they
have on board.

Consider also this, many sailors today will still lie ahull in a storm
despite proof that a breaking wave at sea will overturn any small boat
caugh abeam. For some reason they think the designer must have designed
the vessel to be safe when used like that. This thinking is as stupid as
the people that rely on air bags to protect them from their atrocious
driving and I for one would wish to help dispel the huge amounts
misinformation in this medium.


Cheers MC

I though I was -or do you think a Bolger micro has an LPS of 180 degrees
too?

Cheers MC

Jonathan Ganz wrote:

Well, you know all about crap. Why don't you tell us.

"The_navigator©" wrote in message
...


Jonathan Ganz wrote:


Well, I like Doug, so I won't comment.

Are you a coprophiliac or are you taken in by his endless BS?

Cheers MC

The navigator© wrote:

...I for one would wish to help dispel the huge amounts
misinformation in this medium.

The best way to do that would be to not post here any more. You could avoid
falling into debt, too.

DSK

Peter Wiley wrote:

Balanced spade rudders with only one support for the shaft - at the top
- are far more prone to failure than rudders with top & bottom support
as provided by a full keel.

Thought that was obvious.

Keep in mind the discussion is seaworthiness, not performance.

Well, a spade rudder hung on a post, with no other support, can be strong
enough. It takes more care with the engineering & materials than most
mass-produced boats can muster.

One of the problems I've seen is that high loads on these type rudders tend
to increase play at the bearings & bushings, which then results in impulse
loads as it begins slamming back & forth. Then the post starts to bend more
on each cycle and fatigues more rapidly. Next thing you know, all you've
got down there is twisted stub.

Another great flaw in 99% of production boats is that the emergency tiller
is laughable.

Fresh Breezes- Doug King

In article , Donals Dilemma
wrote:

On Thu, 04 Dec 2003 09:35:47 +1100, Peter Wiley
wrote:


Balanced spade rudders with only one support for the shaft - at the top
- are far more prone to failure than rudders with top & bottom support
as provided by a full keel.

Thought that was obvious.

You'd think so eh?
However, the engineering of a spade rudder is quite good, working on
the cantilevered beam concept.

Agreed or the failure rate would be even worse. They *need* to be a lot
stiffer/stronger to work at all.

Unfortunately they are not quite as well protected as a full keeled
rudder but nonethe less are covered pretty well by the keel.

True but I wasn't going there - this thread started out on
seaworthiness and if we bring into it the ability to survive a
collision with a hard object, all boats are going to fail - just
depends on how big an object and at what speed the collision.

I'd content that most rudder failures are during racing where streese
are high, full keelers don't race anywhere near as much making the
incidence of spade rudder failure appear much higher.

Maybe. Seems obvious as full keel boats aren't these days much use for
racing and I'd agree that failures of almost anything are going to be
higher when people are building to minimum engineering specs and
maximum stress. I say min engineering specs because each kilo extra
weight over what's needed is a penalty you're hauling around. That's
fine for the intended purpose too.

PDW

It does seem to be true in practice, from what I've read. You need
better engineering to build a spade rudder properly than for a rudder
supported top & bottom. Therein lies the rub....

Spades are a lot more likely to be damaged from impact but is this a
seaworthiness issue? Most small boats aren't designed for collisions or
groundings and really only steel copes reasonably well with one if it's
rock or coral.

Spade rudders are also a lot better for snagging mooring lines, pot
lines, gill nets etc etc.

I have a few other problems with these sorts of thing but they're all
related to maintenance in places with minimal facilities, not
seaworthiness issues. I've seen, for example, an awful lot of rudders
where the shaft is a solid rod from tiller to rudder bottom. This is
wonderful - until you want to remove the damn thing and oooops -
where's the big hole to drop it into under he boat? Better hope the
tube is brought above the WL if you're going to drop it in the water.
Now, if it's a spade rudder having a flange under the hull & the rudder
blade bolted to it is going to require a bigger flange/stronger bolts
than the same for a keel hung one. Is it worth the hassle? Depends on
where you're going to go.

How about rod rigging? Is this seaworthy? You aren't going to fix a
broken rod easily. An engine buried under a cockpit sole requiring a
contortionist midget to service it, and a chainsaw to get it out if it
breaks? Ditto lack of access to stern glands. Personally such things
interest me far more than whether a vessel has an EPIRB, a SSB or a
liferaft. Those things only help you (at public expense) to be rescued
*after* you have a major problem.

Engineering for long-term maintenance isn't necessary to have a
seaworthy boat, but it saves a lot of pain down the track.

Did Bill Tilman have a seaworthy boat? Would it have passed your NZ
compliance rules?

PDW

In article ,
The_navigator© wrote:

I can see an enginnering basis for that asserion but is it really true?
The rudders with top and bottom support should have a thinner stock
which would break more easily if the boat fell back from a breaking
wave??? Of course impact damage to spades is different problem...

Cheers MC

Peter Wiley wrote:

Balanced spade rudders with only one support for the shaft - at the top
- are far more prone to failure than rudders with top & bottom support
as provided by a full keel.

Thought that was obvious.

Keep in mind the discussion is seaworthiness, not performance.

In article , Donals Dilemma
wrote:


On Wed, 03 Dec 2003 16:14:37 +1100, Peter Wiley
wrote:


On boats with unseaworthy, poorly (or no) supported rudders, yes. On
boats designed for extended cruising with a protected and well
supported rudder, no. Which category does yours fall into?

PDW

Huh?



Oz1...of the 3 twins.

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

Peter Wiley wrote:

It does seem to be true in practice, from what I've read. You need
better engineering to build a spade rudder properly than for a rudder
supported top & bottom. Therein lies the rub....

Spades are a lot more likely to be damaged from impact but is this a
seaworthiness issue? Most small boats aren't designed for collisions or
groundings and really only steel copes reasonably well with one if it's
rock or coral.

Spade rudders are also a lot better for snagging mooring lines, pot
lines, gill nets etc etc.

I have a few other problems with these sorts of thing but they're all
related to maintenance in places with minimal facilities, not
seaworthiness issues. I've seen, for example, an awful lot of rudders
where the shaft is a solid rod from tiller to rudder bottom. This is
wonderful - until you want to remove the damn thing and oooops -
where's the big hole to drop it into under he boat? Better hope the
tube is brought above the WL if you're going to drop it in the water.
Now, if it's a spade rudder having a flange under the hull & the rudder
blade bolted to it is going to require a bigger flange/stronger bolts
than the same for a keel hung one. Is it worth the hassle? Depends on
where you're going to go.

How about rod rigging? Is this seaworthy? You aren't going to fix a
broken rod easily. An engine buried under a cockpit sole requiring a
contortionist midget to service it, and a chainsaw to get it out if it
breaks? Ditto lack of access to stern glands. Personally such things
interest me far more than whether a vessel has an EPIRB, a SSB or a
liferaft. Those things only help you (at public expense) to be rescued
*after* you have a major problem.

Engineering for long-term maintenance isn't necessary to have a
seaworthy boat, but it saves a lot of pain down the track.

Did Bill Tilman have a seaworthy boat? Would it have passed your NZ
compliance rules?


It sure *looked* like a good seaworthy boat. Don't forget the safety
inspection includes the abilities of the skipper.


Cheers MC

Gotta be a first time for everything..... I'm a pragmatist WRT most
things. A racing boat is designed to go fast and if it breaks, too bad.
If it's so heavy that it doesn't break, and it loses to a lighter one
that breaks occasionally, therefore it's useless for its intended
purpose. Same logic for all highly stressed machinery.

Seaworthiness as defined by the NZ govt inspectors..... ? Heh. Matter
of ticking the right boxes, as you've pointed out WRT a perfectly safe
LPG install that they wouldn't pass.

BTW I did my own LPG instaln on my NSW country place. I'm a certified
welder in oxy, stick, MIG & TIG and my FIL is all the above plus
refrigeration. Hasn't leaked in 15 years but it still doesn't meet code
because neither of us had the magic bit of paper. Fortunately I didn't
care, I just used my account with BOC to rent industrial cylinders of
LPG instead. Always a way.

In article , Donals Dilemma
wrote:

Did you just agree with everything I wrote...or was I imagining it?
:-)

On Thu, 04 Dec 2003 12:09:13 +1100, Peter Wiley
wrote:

In article , Donals Dilemma
wrote:

On Thu, 04 Dec 2003 09:35:47 +1100, Peter Wiley
wrote:


Balanced spade rudders with only one support for the shaft - at the top
- are far more prone to failure than rudders with top & bottom support
as provided by a full keel.

Thought that was obvious.

You'd think so eh?
However, the engineering of a spade rudder is quite good, working on
the cantilevered beam concept.

Agreed or the failure rate would be even worse. They *need* to be a lot
stiffer/stronger to work at all.

Unfortunately they are not quite as well protected as a full keeled
rudder but nonethe less are covered pretty well by the keel.

True but I wasn't going there - this thread started out on
seaworthiness and if we bring into it the ability to survive a
collision with a hard object, all boats are going to fail - just
depends on how big an object and at what speed the collision.

I'd content that most rudder failures are during racing where streese
are high, full keelers don't race anywhere near as much making the
incidence of spade rudder failure appear much higher.

Maybe. Seems obvious as full keel boats aren't these days much use for
racing and I'd agree that failures of almost anything are going to be
higher when people are building to minimum engineering specs and
maximum stress. I say min engineering specs because each kilo extra
weight over what's needed is a penalty you're hauling around. That's
fine for the intended purpose too.

PDW



Oz1...of the 3 twins.

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

Sorry, no nothing about Bolger micros.

"The_navigator©" wrote in message
...
I though I was -or do you think a Bolger micro has an LPS of 180 degrees
too?

Cheers MC

Jonathan Ganz wrote:

Well, you know all about crap. Why don't you tell us.

"The_navigator©" wrote in message
...


Jonathan Ganz wrote:


Well, I like Doug, so I won't comment.

Are you a coprophiliac or are you taken in by his endless BS?

Cheers MC

I've never laughed at an emergency tiller.
Finding it then fitting it is the laugh.

My C&C has a stainless steel shaft mounted in the aft locker. It fits neatly
over an exposed fitting in the cockpit. At the top of the shaft is a T shaped
handle.
Even with my formidable upper body strength, I doubt I could steer for long
with so little leverage in rough conditions.
I could lash a length of wood to it and increase leverage...
I think I'll run out and make the mod now!


RB