Ruddery Hell!!!
canalman
rudder post should some how be locked on to its skeg? Should there be
a locking collar of some kind?
I ask because yesterday, with 27 passengers up, Merlin's rudder was
lifted bodily off the skeg when it hit something nasty
underwater....probably not helped by the lowish water level.
Steering the boat with the rudder flopping about clonking against the
outside of the skeg was no joke. In desperation, I managed to lift it
mid-stream, and on about the fourth attempt, dropped it back into its
location on the skeg.
But shouldn't it be fixed there? Do rudders normally just sit there
under their own weight?
Tony
praying for rain on the Basy
Neil Arlidge
If Merlin (Which I am led to believe is the R&D shelled ex Waterways
Services "Saucy Sue") has the "Ashai" type top rudder bearing with a ball
race, then the inner collar has a couple of Allen key lock bolts. It is
common practice to leave these some what loose, so that if the bottom of the
blade hits some thing serious then it WILL jump up, to save bending the
rudder blade or rudder stock. Earnest's similar bearing is so set, but after
a while rust locks the two together and after similar rudder collisions
often needs some "help" to relocate. More traditional rudders with the large
none ball race top bearing are helded in place by the weight of the rudder.
--
Neil Arlidge - NB Earnest
Follow the travels of the TNC at http://www.tuesdaynightclub.co.uk
Richard J Sanders
> > under their own weight?
Reminds me a problem we had in the first week of use of our shared boat. The
previous week a part owner had 'cilled' the stern and broken off the skeg
supporting the rudder. This had been repaired. I clipped the rudder on the
rear gates of a lock and the rudder jumped out of its support. It took 90
minutes to relocate the rudder back in its cup. The rudder became dislodged
a second time that week when we had a large amount of BW orange fencing
wrapped around the prop. This time one of us got into the canal to 'feed'
the rudder into the cup and so it only took a few minutes. I believe that
during the following weeks the boat had a habit of 'dropping' the rudder.
At the AGM of the boat there was much discussion - particularly about the
fact that the rudder pivot is conical shaped and so was the original
supporting cup, but the new cup was cylindrical. The interpretation was that
the rudder was somehow riding up the cup - with three engineers as part
owners and the original boatyard involved and the repairer you can imagine
there were many diverse opinions. In the end, the rudder bedded in and there
were no more problems.
Richard Sanders
nb Mad Hatter
canalman
>
> If Merlin (Which I am led to believe is the R&D shelled ex Waterways
> Services "Saucy Sue") has the "Ashai" type top rudder bearing with a ball
> race, then the inner collar has a couple of Allen key lock bolts. It is
> common practice to leave these some what loose, so that if the bottom of the
> blade hits some thing serious then it WILL jump up, to save bending the
> rudder blade or rudder stock. Earnest's similar bearing is so set, but after
> a while rust locks the two together and after similar rudder collisions
> often needs some "help" to relocate. More traditional rudders with the large
> none ball race top bearing are helded in place by the weight of the rudder.
Thanks Neil!!
Tiz as I suspected then. The Allen key lock bolts are entirely
missing, but in view of the state of the Basy bottom at present, I
think I'll leave things as tiz.
Yes....Merlin is Saucy Sue after a sex change.
Tony
its drizzling on the Basy
Neil Arlidge
To make sure the shaft does not lock on the inner rudder bearing with rust I
smear some grease round this joint...............often a lot comes up the
bearing when I use the grease gun on the bearing greaser!
--
Neil Arlidge - NB Earnest - In bits yet again............
Steve King
>Can any of you techno wizz boat-builders tell me if a narrowboat
>rudder post should some how be locked on to its skeg? Should there be
>a locking collar of some kind?
>
>I ask because yesterday, with 27 passengers up, Merlin's rudder was
>lifted bodily off the skeg when it hit something nasty
>underwater....probably not helped by the lowish water level.
>
>Steering the boat with the rudder flopping about clonking against the
>outside of the skeg was no joke. In desperation, I managed to lift it
>mid-stream, and on about the fourth attempt, dropped it back into its
>location on the skeg.
That's exactly how rudders worked on ex-working narrow boats. I had
the misfortune to unship the rudder on Water Rambler once on the Zoo
Bus run. With a lot of effort to lift it I thought I'd got it back in
ok, only to find that it later fell off the skeg with the tiller
slanting down into the hatches, which rather limits the ability to
steer the boat ! The back of the skeg sometimes has a notch to receive
the pivot pin on the end of the rudder pole to guide it back in as
it's lifted. Modern boats may well vary from this practice though.
Steve
Ian McCarthy
swans neck up to the limit of travel and then lower it down attempting
to feel the skeg rudder cup. In days of your when canal were not as well
dredged as they are now, it was a fairly common activity. The design
was done so it would slip out rather than suspend the boat on the back
of the counter.
--
Cheers Ian Mac
ps I can only just lift ours when its in water its to heavy, when on dry
land, it then takes two of us.
timleech
One of my pet gripes about modern steel NB's is that 99% of builders
seem to regard the steering gear as almost an afterthought, rather
than something fundamental to the boat, both to its proper handling
and to the well-being of the poor sod who spends all day glued to it.
A stock question owners ask when bring their boat along for a routine
blacking is "can you do something about the tiller/rudder, it keeps
rattling?". The usual main reason for the rattling is that is wasn't
built sufficiently rigidly in the first place, and putting that right
properly can be a very expensive excercise - they are hoping for a
quick fix with a new bearing or the odd bolt tightened, etc, which may
alleviate the problem but won't properly cure it.
To my mind, there's no better system for conventional counter stern
NB's & the like than the old one, ie a good, solid, rigid, heavy
one-piece rudder & post, sitting in a plain cup on the skeg, with the
post passing through a generous sized tube through the counter such
that it can be unshipped by lowering the whole thing past the skeg. If
it's heavy enough there's no need for fancy bearings at the top - a
plain cast iron bush will do fine, anyway ball bearings don't last
long in this situation. Top it off with a good rigid ram's head & you
wont find a better system.
Two-piece rudders are always prone to trouble, and reliance on tight
bearings to prevent rattle is doomed to fail because the bearings
won't stay tight for long. A lot of 'rattling' can be traced to
inadequate torsional stiffness of the whole assembly.
A personal view is that any balance on the front of the rudder should
be minimal, but that's a different issue <G>
In answer to the question, as others have said, usually the rudder is
arranged such that it *can* lift, to reduce the risk of damage.
Regarding top ball bearings, generally these are best left slack , (a)
to *allow* the rudder to lift, and (b) so that the weight of the
rudder is carried on the skeg, as this way a lightly built rudder will
be less prone to rattling.
Cheers
Tim
Tim Leech
Dutton Dry-Dock
Traditional & Modern canal craft repairs
Neil Arlidge
> One of my pet gripes about modern steel NB's is that 99% of builders
> seem to regard the steering gear as almost an afterthought, rather
> than something fundamental to the boat, both to its proper handling
> and to the well-being of the poor sod who spends all day glued to it.
Rather well put Tim!
--
Neil Arlidge - NB Earnest - A "modern steel NB" whose second rudder bears
little resemblance to the original one..............
Adrian Stott
<idm.pl...@cronkshaw.nospan.com> wrote:
>Steve King wrote:
>> On 21 Sep 2003 16:48:34 -0700, hellp...@aol.com (canalman) wrote:
>>
>>
>>>Can any of you techno wizz boat-builders tell me if a narrowboat
>>>rudder post should some how be locked on to its skeg? Should there be
>>>a locking collar of some kind?
>>>
>>>I ask because yesterday, with 27 passengers up, Merlin's rudder was
>>>lifted bodily off the skeg when it hit something nasty
>>>underwater....probably not helped by the lowish water level.
>>>
>>>Steering the boat with the rudder flopping about clonking against the
>>>outside of the skeg was no joke. In desperation, I managed to lift it
>>>mid-stream, and on about the fourth attempt, dropped it back into its
>>>location on the skeg.
Many years ago, I took a group of friends on a rented full-length
Middlewich boat (might have been Oak) on a canal holiday. Going down
the Shroppie, my girl friend's father in ignorance kept the boat at
the back of the lock. Yep, caught the sill, and the rudder post
lifted from its cup. Blush.
And we couldn't get it back, no way. So we struggled back to base,
where the boys lifted the whole rudder assembly out in a trice and put
in one of the several spares kept for just this purpose.
The reason we couldn't get it back was immediately apparent. The
rudder shaft had bent. The usual case, we were told.
GBP 25 charge. But GF's dad paid, so all was well.
Adrian
PS A nice trick for seeing what is going on under water is to use a
glass jar (or drinking glass) with a clear and flat bottom. Stick the
bottom into the water, and look through it. Like using goggles.
Didn't help us much with Oak, though.
AS
Andrew Instone-Cowie
> Many years ago, I took a group of friends on a rented full-length
> Middlewich boat (might have been Oak)
Oak is up for sale in this month's Waterways World.
Andrew
--
Neil Arlidge
.......wonder if the new owners will sell all the "character" boats?
.......maybe Robin Nicholson should put in a bid for Maple!
--
Neil Arlidge - NB Earnest - a boat with a character all of its own.........
canalman
> PS A nice trick for seeing what is going on under water is to use a
> glass jar (or drinking glass) with a clear and flat bottom. Stick the
> bottom into the water, and look through it. Like using goggles.
>
How do you strap it on your head?????
Tony
raising a glass on the Basy
brian
"timleech" <timl...@dutondok.u-net.com> wrote in message
news:vq75nv48iuqdmh0vg...@4ax.com...
> On Mon, 22 Sep 2003 23:01:56 GMT, steph...@spamstopeasynet.co.uk
> (Steve King) wrote:
>
> >On 21 Sep 2003 16:48:34 -0700, hellp...@aol.com (canalman) wrote:
> A personal view is that any balance on the front of the rudder should
> be minimal, but that's a different issue <G>
Tim
I am interested in this point as a short time back I asked if there was a
magic formula for the rudder proportions. Mine has 9" in front of the stock
and 18" behind. If I let go of the tiller it swings to the left or right but
never stays straight. I was going to have an inch staved off the front and
3" added to the back to improve things. I was told that the larger area at
the front was beneficial as it stopped the forward thrust of the prop when
turning hard>
>
> Cheers
> Tim
--
___
Brian from sunny Suffolk by the river Hundred
Tim Lewis
>From: Andrew Instone-Cowie address-...@datagram.co.uk
>Date: 25/09/2003 11:07 GMT Daylight Time
>Message-id: <bkuejj$5v5n5$1...@ID-153085.news.uni-berlin.de>
I had several excellent hoidays on Oak in the early 1980's, it was/is an great
boat for large groups to hire. Amazed that a wooden top boat has lasted this
long in a hire fleet, it wasn't exactly new when we hired it.
*************************
Tim Lewis
Home e-mail: t...@timlewis.org.uk
Web Page: http://www.timlewis.org.uk
NB Fulbourne: http://www.fulbourne.org.uk
Home phone: 020 8367 6227
Mobile phone: 07802 518094
****************************
Robin Nicholson
>> Oak is up for sale in this month's Waterways World.
>
>.......wonder if the new owners will sell all the "character" boats?
>.......maybe Robin Nicholson should put in a bid for Maple!
>Neil Arlidge - NB Earnest - a boat with a character all of its own.........
Hah! I have for long had ideas about getting my own craft. One thing
is for sure, I might name the damn thing Dragon.
I do not think the new owner is selling the character boats: Oak was
really tired. It had a new bottom added a couple of years ago which
IIRC gave it extra weight - someone said it was just over 20 tons.
I have had absolutely no further comment from the company about
Standedge Tunnel, by the way, having shown it has been through it
twice.
A friend is on Maple at the moment and I am urging him to make some
enquiries on Saturday
--
Robin
timleech
There *may* be a bit of truth in that, but my guess is only a bit, and
then only up to a certain rudder angle.
I would *hate* to have to steer a boat like that for any length of
time! To me, it's important to have some proper feeback from the
tiller, so that you are aware of what your tiller waggling is actually
trying to do to the boat.
My early narrow boat steering was mainly deep-draughted 70' ex-working
boats, particularly steering the trip boat Lapwing (ex-FMC), drawing
over 3', along the winding turns of this end of the T&M. In common
with most boats of that ilk, there was no balance at all on the
rudder. Yes, there's a fair bit of physical strength needed to hold
the tiller hard over on full power, but there's also definite
satisfaction to be had from having the boat in 'the right place' on a
winding canal, when a boat like that will almost steer itself with
minimal physical effort. You just couldn't do that without a proper
feedback through the tiller!
Granted it's not quite the same now, as such 'channel' as there is
through the mud no longer follows the 'proper' path round the outsides
of turns etc, this due to the lack of deep-draughted boats passing
through regularly, and the large numbers of shallow-draughted boats
which basically go anywhere & everywhere. The effect is still there,
though.
Anyway, after that little rant, I'd suggest (without seeing the boat)
taking *six* inches off the front & adding a similar amount to the
back!
Adrian Stott
"Stick the bottom into the water, and look through it". That advice
applies to using the glass jar, as well.
Adrian
Gavin Gillespie
"Adrian Stott" <ba...@spam.com> wrote in message
news:7918nvspe6tnhujni...@4ax.com...
I've heard of talking through it, but looking through it, that's a new
one ;o)
--
Gavin Gillespie
Nottingham UK
Steve King
<brian.holt@harnser.**business.co.uk> wrote:
>I am interested in this point as a short time back I asked if there was a
>magic formula for the rudder proportions. Mine has 9" in front of the stock
>and 18" behind. If I let go of the tiller it swings to the left or right but
>never stays straight. I was going to have an inch staved off the front and
>3" added to the back to improve things.
The general rule of thumb for a rudder with 'leading edge' is a
proportion of 1:4 or 1:5 (leading to trailing). In this situation I
would remove some leading edge but not add any trailing edge.
4.5 ins : 18 ins should give a better result, but might still be a bit
'overbalanced'. Best to leave too much on and remove a bit more next
docking.
> I was told that the larger area at
>the front was beneficial as it stopped the forward thrust of the prop when
>turning hard
The leading edge *will* collect more propwash when turning (a good
thing) but it can overbalance the rudder when going straight ahead if
there is too much.
For optimum steering the back of the prop will be close to the front
of the rudder. With some few inches of space in this particular
installation (having removed some leading edge) you may find that the
propwash 'fans out' and is slightly less efficient for turning than a
closer arrangement.
Steve
timleech
(Steve King) wrote:
>On Thu, 25 Sep 2003 18:47:38 +0100, "brian"
><brian.holt@harnser.**business.co.uk> wrote:
>
>>I am interested in this point as a short time back I asked if there was a
>>magic formula for the rudder proportions. Mine has 9" in front of the stock
>>and 18" behind. If I let go of the tiller it swings to the left or right but
>>never stays straight. I was going to have an inch staved off the front and
>>3" added to the back to improve things.
>
>The general rule of thumb for a rudder with 'leading edge' is a
>proportion of 1:4 or 1:5 (leading to trailing). In this situation I
>would remove some leading edge but not add any trailing edge.
>4.5 ins : 18 ins should give a better result, but might still be a bit
>'overbalanced'. Best to leave too much on and remove a bit more next
>docking.
>
The 1:5 figure is often quoted, but I wonder on what criteria it is
based? It must to a large degree (in the case of a tiller steered
boat, at least) be a very subjective and individual thing. As I've
already said, my own preference is to have plenty of feedback via the
tiller.
Brian's 1:2 is way off the normal scale, though <G>
Just out of curiosity, I've just measured the rudder of the Large
Northwich motor that I have on the dock at the moment, the rudder has
22" behind the rudder post & 3" of balance in front (ie just over 1:7)
My recollection (may be wrong) is that the Small Woolwich motor, in my
view one of the nicest narrow boats to handle, has slightly less
'balance' on a similar size rudder.