Advantage of tiller to one sidel when on mooring?

[LittleSister]

In a thread about something completely different, Daydream Believer mentioned in passing 'my boat shears about all over the place on a mooring if the tiller is left to port (as required by the mooring lease holders)'.

I'm curious as to why the mooring lessor might require that. (I can't see the advantage.)

I can certainly imagine that a boat will sheer around more if the tiller is offset, especially if it offset substantially and hence the rudder is stalling in the tide, and not performing its complementary role to the keel in keeping the boat steady.

(I wonder whether the lessor's requirement for an offset tiller specifies quite how offset (would 1/4" be enough?), or demands that the offset tiller is actually connected to the rudder at the time.)

 

[NealB]

Just guessing: maybe it's to 'encourage' all the boats to swing the same way as the tide changes?

 

[LittleSister]

Just guessing: maybe it's to 'encourage' all the boats to swing the same way as the tide changes?

Good guess on your part.

I suspect, though, that it either it wouldn't make any difference or (partly for the reasons outlined above) would actually increase the likelihood of them going in different directions. Apart from anything else, the tendency of them to go in the the same direction would reduce as the tie slackens, so, it would work, but only when it wasn't needed! (All guesswork on my part, too.)

 

[NealB]

Good guess on your part.

I suspect, though, that it either it wouldn't make any difference or (partly for the reasons outlined above) would actually increase the likelihood of them going in different directions. Apart from anything else, the tendency of them to go in the the same direction would reduce as the tie slackens, so, it would work, but only when it wasn't needed! (All guesswork on my part, too.)

Yes ...... a very tentative guess (hence the inverted commas) , with which there are many possible flaws!

 

[mjcoon]

Just guessing: maybe it's to 'encourage' all the boats to swing the same way as the tide changes?

Sort of political? (Dangerous territory!)

 

[NealB]

Sort of political? (Dangerous territory!)

Yes .......... despite our best human efforts at control, boats are good at revealing unintended ambiguities.

 

[penfold]

Weird, I can't see how that helps the mooring provider unless they only lease moorings to one kind of hull(all long keel, all fin keel etc); even then the effect is going to be so random at slack water. Do the moorings have swivels? I assume yes as they'd end up in a right old fankle if not.

 

[Buck Turgidson]

When the tide is flowing they will all veer the same way

 

[LittleSister]

It's an old wives' tale!

I'm increasingly convinced that the idea that tillers lashed to one side help align moored boats to one another is an old wives' tale.

But I'm genuinely happy to be persuaded otherwise if anyone can explain the mechanism by which the effect is achieved. that's your challenge

When the tide is flowing they will all veer the same way

They will do so even more so, though, if the the tillers are lashed centrally!

 

[penfold]

Shouldn't make any practical difference unless the mooring provider is putting them too close together or putting wildly differing craft adjacent, i.e. a catamaran next to an 8 metre.

 

[DanTribe]

The real benefit is when the tide turns from slack to wind over tide. Boats with tiller to port will tend to turn together. If the tiller is central they can break shear and cause mahem.

 

[LittleSister]

The following are quotes from Daydream Believer (with his permission) with whom I've now had a an exchange of PMs about the matter.

(n.b- I've no beef with Daydream Believer at all! I'm just interested in thinking through and trying to better understand the logic of lashing the tiller to one side, and it was just chance that a passing remark of his on another thread reminded me of something I'de puzzled about before. He's also a lot of experience of moorings.)

"When our moorings were full they were fairly close together. So the first thing my predecessors did was try to put boats of a similar nature together. That way they all sat at the same attitude in the tide. In addition they tend to swing the same way as it turns.
Of course that was older long keel & bilge keel boats that were prevalent on our moorings.
It was very useful when we had 19 Squibs all in line as we could use less space.
Our rules state tillers to be lashed to port. The squib class had temporary rudders for the moorings so that their racing rudders could be shipped when not being used.
My boat, with its deeper narrow fin, sails on the fin & can do complete 360 degree flips if the tiller is left tied over. So if it is ever moored, I have to lash the tiller amidships.
In the 70's I was based at Burnham on Crouch & the river was jammed with moorings. The Stella class had 30 plus boats in 2 rows. It was essential that the tillers were tied over the same, as the moorings were so close, that some boats were only one boats length apart. I do not recall any clashing"

After I had said 'I'm still not clear by what mechanism having the tiller lashed over is supposed to result in them all lying at the same attitude to the tide, or turn the same way when it turns', he responded.

"Well it makes them all sit one way rather than some sit one way & some the other. If some people put their tillers central, some to port & some to stbd they would all sit in opposit angles. This would be made worse by the wind. Generally the boats will swing the same way as the tide turns & pushes the back of the rudder.
Most people would tie their rudders to prevent them banging from side to side & wear on those with pintals as on , say, westerleys with transom mounted rudders, where they have acetal or delrin bearings. That is just goodpractice.
One also has to consider other craft passing between the trots. It is not good to have boats swinging into the fairway between, making passage difficult for others on tight trots. .
We just consider it good practice. I was taught to do this when I had a boat on Tucker Browns moorings on the Crouch back in the 70s. There were lots of boats in tight proximity . The ferry man would always comment when he picked us up to take us ashore & make sure we did not forget. Embarrassing to have to get back on board with 10 others waiting on the ferry because one had forgotten to lash the tiller."

I agree with him that
- it is preferable for boats on swinging moorings to all lie facing the same direction so far as possible.
- tillers of boats moored in proximity should ideally all be lashed in the same position as one another to help such alignment; and
- that boats (such as Squibs) will range around much less if they have a rudder in place with its position locked (and if racing rudders are removed a 'temporary' mooring rudder is desirable to achieve this).

I believe that lashing rudders centrally would be more effective in aligning boats on neighbouring moorings than lashing them to one side.

THE CHALLENGE!
Can anyone provide a reasoned explanation as to why lashing tillers to one side would be more effective in aligning moored boats than lashing them centrally?

 

[LittleSister]

The real benefit is when the tide turns from slack to wind over tide. Boats with tiller to port will tend to turn together. If the tiller is central they can break shear and cause mahem.

How so?

It is a common claim/assumption, but no one has yet explained how this supposed advantage over centralised rudders actually happens.

 

[KevinV]

The only thing that makes any sense to me is if it might possibly help prevent "searching" on the mooring to the current (as many wide transom boats do at anchor in the wind), much the same as lashing the boom to one side can do for wind? No idea if it's a thing, but it seems plausible to me.
Or, more likely, just preventing having a mishmash of boats some lashed to port, some to starboard, some central or not at all - which would certainly all behave differently in a (change of) current.

 

[LittleSister]

The only thing that makes any sense to me is if it might possibly help prevent "searching" on the mooring to the current

How?

Or, more likely, just preventing having a mishmash of boats some lashed to port, some to starboard, some central or not at all - which would certainly all behave differently in a (change of) current.

But lashing them centrally would achieve at least the same, and almost certainly better.

 

[AntarcticPilot]

How?



But lashing them centrally would achieve at least the same, and almost certainly better.

Lashing the tiller centrally obstructs far more of the cockpit than lashing it to one side. A non-issue on my boat, because the tiller is hinged so I can lift it up and lash it to the backstay, but in that case, the lashing doesn't have much mechanical advantage, so the rudder can still potentially move from the position it is parked in. If you want to be sure the rudder is in a particular position, you probably need the tiller down, with lines across the cockpit in the case of a tiller lashed centrally.

 

[James_Calvert]

Assume a strong wind from directly astern (6 o' clock) with the boat pointing into a strong tidal flow (from 12 o' clock).

With the tiller to port, the boat will turn to starboard and take up a sheer, a stable condition with the boat pointing now between 1 o' clock and 2 o' clock, with the boat ranging around on the scope of the mooring within an arc from say 1 o' clock to 5 o' clock, depending on the relative strengths of the wind and tide.

A boat with the tiller tied to starboard in the same conditions will take the opposite sheer, so range about in the 11 o' clock to 7 o' clock sector.

A boat with the tiller tied amidships will still sheer about from the influence of the wind from astern, but it isn't a stable condition, so it will charge about all over the place.

That's the theory.

 

[Daydream believer]

THE CHALLENGE!
Can anyone provide a reasoned explanation as to why lashing tillers to one side would be more effective in aligning moored boats than lashing them centrally?

Because it puts the boat into a stalled "hove too" position as the rudder sails the boat against its keel. It then sits in a "forced" position.
With the rudder centrally that does not happen & the boat can wander from side to side

 

[xyachtdave]

What about wheel steering?

If I lash my wheel to port the boat swings the opposite way.

I just leave it in the middle.

 

[Daydream believer]

What about wheel steering?
If I lash my wheel to port the boat swings the opposite way.
I just leave it in the middle.

Yes , I heard that you were liable to "swing the other way"