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I've always moored with my ropes at about 45 degrees away from the boat, ie the front rope in front and vice versa. Lately I've seen more and more tied with the ropes going the other way, sometimes almost at right angles but just a fraction back from the wotsit on the boat they're fixed to.. They mostly seem to be dumped boats, perhaps trying to make the ropes less obvious to passing strangers with cutting implements.

 I'm trying to work out if it should make any difference, but they do seem to crash about more as I go past.

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There's probably a mathematical way to prove it, but I think 45deg minimises boat movement, based on a narrowboat-shaped-boat (ie a rectangle with slight boat-like shape front and almost no curves at the rear).

 

Would be interesting if these examples you've seen are on rings or pins - pins there's no excuse, on rings then I will compromise on an angle between about 20deg-70deg before going to ring + (nappy) pin.

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At 90 degrees a snug rope will get very tight as the water level changes.    Angled ropes have more capacity to cope with level changes.  Loose ropes at an angle together with spring lines are even better at holding the boat steady and coping with level changes.

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22 minutes ago, Paul C said:

There's probably a mathematical way to prove it, but I think 45deg minimises boat movement, based on a narrowboat-shaped-boat (ie a rectangle with slight boat-like shape front and almost no curves at the rear).

 

Would be interesting if these examples you've seen are on rings or pins - pins there's no excuse, on rings then I will compromise on an angle between about 20deg-70deg before going to ring + (nappy) pin.

It depends how big the forces are in the two directions (fore-and-aft and laterally) that the rope is trying to resist and stop movement in. At 45 degrees the "stiffness" is the same in both directions at 70% of the rope tension. But for a moored boat being passed by a moving one, most of the pull on the boat is likely to be fore-and-aft not away from the bank, so it would be better to have the ropes at a smaller angle to the bank -- for example if they're at 30 degrees (further away from bow and stern) instead of 45 degrees the stiffness is 87% fore-and-aft (24% higher) but 50% laterally (29% lower). Going much further out than this (lower than 30 degrees) doesn't give much gain in the fore-and-aft stiffness but loses a lot more lateral stiffness. The shape of the hull affects this a bit, but not by much for a long thin narrowboat.

 

The best option of all is to have two ropes at each end, one at 90 degrees to prevent lateral movement (with some slack if there might be level changes), and one parallel with the bank (a spring line) to prevent fore-and-aft movement, but this needs either four stakes/rings in the right places (ropes to bow T-stud and stern dollies) or four attachment points on the boat (eyes on the gunwales spaced in from bow/stern) -- that's what I've had fitted.

 

Just ropes at 90 degrees is a terrible idea, there's little resistance to any fore-and-aft movement which causes massive stresses in the ropes and pulls on mooring stakes -- they'll usually pull out as the boat moves fore and aft by large amounts... 😞

Edited by IanD
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I’m moored now with my ropes going the other way

simply, for me, because of the bollard spacing. 
But My ropes (I think, I’ll look when I get back) are also set less than 45. 
My boat will travel gently forward and back maybe a foot, maybe two🤷‍♀️
But I like it, I have some nice tyre fenders so it’s ok 

Main thing is the boat doesn’t pull away from the bank, that’s horrible. 
But a gentle forward and back I find pleasant. 
 

so I think it’s safe to say the less angle the tighter you’ll stay to the bank but more likely to go back and forth. 
the wider the angle the less likely you’ll go back and forth but you will swing out from the bank. 
 

But, you know all that any way Arthur. My simple answer is the bollards have dictated for me how  my ropes point the other way. Perhaps it the same for the boats you’ve observed? And by the way I can’t be assed putting out a springer line because I like the boat movement. 

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7 minutes ago, Goliath said:

I’m moored now with my ropes going the other way

simply, for me, because of the bollard spacing. 
But My ropes (I think, I’ll look when I get back) are also set less than 45. 
My boat will travel gently forward and back maybe a foot, maybe two🤷‍♀️
But I like it, I have some nice tyre fenders so it’s ok 

Main thing is the boat doesn’t pull away from the bank, that’s horrible. 
But a gentle forward and back I find pleasant. 
 

so I think it’s safe to say the less angle the tighter you’ll stay to the bank but more likely to go back and forth. 
the wider the angle the less likely you’ll go back and forth but you will swing out from the bank. 
 

But, you know all that any way Arthur. My simple answer is the bollards have dictated for me how  my ropes point the other way. Perhaps it the same for the boats you’ve observed? And by the way I can’t be assed putting out a springer line because I like the boat movement. 

The problem is that as the angle of the lines gets lower than 45 degrees this multiplies the force in the ropes and on the moorings -- not a problem with rings, but not a good idea with mooring spikes, especially in softer ground. The boat moves back and forth and the increased force and movement pulls the spikes loose, and eventually they come out -- ropes at 90 degrees to spikes is a recipe for disaster... 😞

 

Having the ropes pointing inwards instead of outwards (closer together on bank than on boat) works almost as well as outwards, but can rub paint off if they touch the cabin. DAMHIK...

Edited by IanD
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7 minutes ago, Goliath said:

I’m moored now with my ropes going the other way

simply, for me, because of the bollard spacing. 
But My ropes (I think, I’ll look when I get back) are also set less than 45. 
My boat will travel gently forward and back maybe a foot, maybe two🤷‍♀️
But I like it, I have some nice tyre fenders so it’s ok 

Main thing is the boat doesn’t pull away from the bank, that’s horrible. 
But a gentle forward and back I find pleasant. 
 

so I think it’s safe to say the less angle the tighter you’ll stay to the bank but more likely to go back and forth. 
the wider the angle the less likely you’ll go back and forth but you will swing out from the bank. 
 

But, you know all that any way Arthur. My simple answer is the bollards have dictated for me how  my ropes point the other way. Perhaps it the same for the boats you’ve observed? And by the way I can’t be assed putting out a springer line because I like the boat movement. 

The ones I've seen are just on nappy pins on the piling. I wondered if the direction of the ropes made any difference to the security as one came off as I crept past.

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🤷‍♀️ Could be their thinking. 
Personally I’d be putting ropes out to goat chains to be more secure if leaving the boat. 
And wouldn’t leave it anywhere I thought weren’t secure. 

 but yeah, who knows how other folk think. 

7 minutes ago, IanD said:

The problem is that as the angle of the lines gets lower than 45 degrees this multiplies the force in the ropes and on the moorings -- not a problem with rings, but not a good idea with mooring spikes, especially in softer ground. The boat moves back and forth and the increased force and movement pulls the spikes loose, and eventually they come out -- ropes at 90 degrees to spikes is a recipe for disaster... 😞

 

Having the ropes pointing inwards instead of outwards (closer together on bank than on boat) works almost as well as outwards, but can rub paint off if they touch the cabin. DAMHIK...

I’m not in ‘spikes’ though am I?

Im on bollards 

If I were on spikes I could dictate meself where to hammer them in and I’d be putting two ropes out front and back. 

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5 minutes ago, Goliath said:

🤷‍♀️ Could be their thinking. 
Personally I’d be putting ropes out to goat chains to be more secure if leaving the boat. 
And wouldn’t leave it anywhere I thought weren’t secure. 

 but yeah, who knows how other folk think. 

 

There are plenty of people along here (GU Paddington Arm) who use mooring spikes with ropes at almost 90 degrees to the bank and leave the boat. Every time a widebeam/working boat has been along I see them drifted out right across the canal with a hole in the bank where their mooring spikes used to be...

Edited by IanD
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I'd (almost*) never moor with ropes inwards to the boat (ie towards the middle, rather than outwards) because 1) the ropes wear the paint off the boat bodywork and 2) they are a trip hazard. I know there's various ways to get around both, but my boat isn't fitted with the extra accessories etc, and its definitely less secure anyway so would never be done. If the bollards/rings simply didn't allow for the "normal" mooring angle and forced an inwards, I'd stick a pin in, either nappy onto armco or a mooring pin; and if there's nowhere to put the pin, choose another mooring or find some other novel way of getting a pin in.

 

* About the only time its actually needed to be done is half-length pontoons, eg those at Llangollen basin.

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Well maybe you should tell them how to do it correctly. 
Take a flip chart with you next time and demonstrate through dia

3 minutes ago, IanD said:

 

There are plenty of people along here (GU Paddington Arm) who use mooring spikes with ropes at almost 90 degrees to the bank. Every time a widebeam/working boat has been along I see them drifted out right across the canal with a hole in the bank where their mooring spikes used to be...

You need to take a flip chart on your rounds and demonstrate with diagrams the errors they are making. 
Im sure they’d appreciate your help. 

 

3 minutes ago, Paul C said:

I'd (almost*) never moor with ropes inwards to the boat (ie towards the middle, rather than outwards) because 1) the ropes wear the paint off the boat bodywork and 2) they are a trip hazard. I know there's various ways to get around both, but my boat isn't fitted with the extra accessories etc, and its definitely less secure anyway so would never be done. If the bollards/rings simply didn't allow for the "normal" mooring angle and forced an inwards, I'd stick a pin in, either nappy onto armco or a mooring pin; and if there's nowhere to put the pin, choose another mooring or find some other novel way of getting a pin in.

 

* About the only time its actually needed to be done is half-length pontoons, eg those at Llangollen basin.

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Just now, Goliath said:

Well maybe you should tell them how to do it correctly. 
Take a flip chart with you next time and demonstrate through dia

You need to take a flip chart on your rounds and demonstrate with diagrams the errors they are making. 
Im sure they’d appreciate your help. 

 

Sarcasm is the lowest form of wit... 😉

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4 minutes ago, Goliath said:

Well maybe you should tell them how to do it correctly. 
Take a flip chart with you next time and demonstrate through dia

You need to take a flip chart on your rounds and demonstrate with diagrams the errors they are making. 
Im sure they’d appreciate your help. 

 

is this for me? I am unsure because you've quoted it in a weird way?

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4 minutes ago, Paul C said:

I'd (almost*) never moor with ropes inwards to the boat (ie towards the middle, rather than outwards) because 1) the ropes wear the paint off the boat bodywork and 2) they are a trip hazard. I know there's various ways to get around both, but my boat isn't fitted with the extra accessories etc, and its definitely less secure anyway so would never be done. If the bollards/rings simply didn't allow for the "normal" mooring angle and forced an inwards, I'd stick a pin in, either nappy onto armco or a mooring pin; and if there's nowhere to put the pin, choose another mooring or find some other novel way of getting a pin in.

 

* About the only time its actually needed to be done is half-length pontoons, eg those at Llangollen basin.


Jesus, this is hard work. 
they’re bollards set in stone. 
No Armco, no grass. 
Sometimes you do what you need to do. 
 

 

2 minutes ago, IanD said:

Sarcasm is the lowest form of wit... 😉

 

 

not sure I was trying to be witty

 

just suggesting you could help your fellow boaters 

rather than berating them

 

 

 

 

4 minutes ago, Paul C said:

is this for me? I am unsure because you've quoted it in a weird way?

Oh I don’t know

 

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2 minutes ago, Goliath said:


Jesus, this is hard work. 
they’re bollards set in stone. 
No Armco, no grass. 
Sometimes you do what you need to do. 
 

 

Its not my place to tell other boaters what to do. All I did was say what I'd  do in a given hypothetical situation. 

 

If they're bollards in the wrong place, I'm not going to be using them.

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2 minutes ago, Goliath said:

not sure I was trying to be witty

 

just suggesting you could help your fellow boaters 

rather than berating them

 

 

I wasn't berating them -- you wondered how other people think, and I was pointing out how some of them round here seem to think. Or not... 😉

 

If you're willing to go up to an unknown boater (who may not react well to criticism from a passerby) and tell them how they're moored wrongly and how they ought to do it, you're a braver man than I am... 🙂

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1 hour ago, Paul C said:

I'd (almost*) never moor with ropes inwards to the boat (ie towards the middle, rather than outwards) because 1) the ropes wear the paint off the boat bodywork and 2) they are a trip hazard.


Genuine question - how are ropes inwards to the boat more of a trip hazard than ropes outwards?

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10 minutes ago, Col_T said:


Genuine question - how are ropes inwards to the boat more of a trip hazard than ropes outwards?

Because you invariably get off either/both at bow and stern; and ropes inwards will be a few inches away, or on, the deck are where you would trip. Just as a sanity check, this is on a narrowboat where the dolly is at the back (near the rudder tube) and the front T stud, is at the front of the boat.

 

Black rope - not a trip hazard

Natural coloured rope - is a trip hazard

DSC_2721ee.jpg

Edited by Paul C
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5 minutes ago, Col_T said:


Genuine question - how are ropes inwards to the boat more of a trip hazard than ropes outwards?

On my stern the rope will go from the dolly straight across my path for stepping off. 
So not a good idea. 
But being as I put it there I know it’s there. 
Ideally one wouldn’t do it. 
 

I’ll take a photo of it tomorrow as I fall in and smash me face and get minced by the prop that’s in gear while tied to the bank. The other foot will have missed too from the diesel I spilt when topping up the tank. 
I’ll be wearing sandals as well

in the dark while wearing sunglasses 
At least I won’t bang me head on a rail or tractor seat on the way down, unless it’s on the back of the other boat. 
Hopefully the paint will be ok. 
God forbid that gets scratched. 
 

 

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I've never found mooring on a canal to be a subject that needs too much analysis.

 

I often moor in the fashion @Arthur Marshall describes simply because I have a preference for mooring to the very solid objects the navigation authority provides for the purpose and it so happens the normal spacing of these compared to my boat length results in that being the most practical way of so doing.

 

It's a potential trip hazard if those lines come back at angle sufficent to run across where you will naturally walk or step for access to and from the boat. They generally don't in my case because the end up fairly square. I use big rope fenders to cushion the boat against the side. These are a necessity for a boat with low freeboard to prevent the gunwales from going beneath walings.

 

If I use piling hooks I'll attempt to get them at 45 degrees but I don't fuss too much about it. I've never used goat chains.

 

The main thing is to get the lines nice and tight - ideally doubled up for ease of untying - and simply secured to the dolly/stud/cleat.

 

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Now, I never double up. 
Probably because I have short ropes. 
 

and I’ve started to simply do turns around the T stud and snatch the turns rather than tie. 
 

the stern I just have a loop on either end so no tying either. To shorten or tighten I just give it a few more turns around and across each dolly and then loop over.  Take the slack off the back end by tightening the front end. 
Put engine in gear if it helps while tightening ropes. 

 

Leaving the boat unattended for a few days I will be a bit more particular. 

56 minutes ago, Paul C said:

Because you invariably get off either/both at bow and stern; and ropes inwards will be a few inches away, or on, the deck are where you would trip. Just as a sanity check, this is on a narrowboat where the dolly is at the back (near the rudder tube) and the front T stud, is at the front of the boat.

 

Black rope - not a trip hazard

Natural coloured rope - is a trip hazard

DSC_2721ee.jpg


aaahh well,

that is quite a very high counter,

and therefore a very high risk hazard,

 

other counters may be much lower,

perhaps half that height and the risk lower. 
 

I would have to modify my risk assessment sheets quite drastically to cope with that difference. (High counter)
 

I guess that be a springer line because you already got a rope going the other way. 
Is the risk of an extra rope necessary?

Edited by Goliath
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3 hours ago, Arthur Marshall said:

I've always moored with my ropes at about 45 degrees away from the boat, ie the front rope in front and vice versa. Lately I've seen more and more tied with the ropes going the other way, sometimes almost at right angles but just a fraction back from the wotsit on the boat they're fixed to.. They mostly seem to be dumped boats, perhaps trying to make the ropes less obvious to passing strangers with cutting implements.

 I'm trying to work out if it should make any difference, but they do seem to crash about more as I go past.

 

Well you are in luck young sir.

Just last year I qualified as a narrowboat hydrodynamics engineer (specialising in mooring) from the University of the Whitchurch Arm.

I can tell you quite categorically that if you tie your ropes at anything other than a 45 degree angle, a pack of flying monkeys will attack you during the night.

Cynics will say its not really a CRT issue, but you'd think they would at least keep an eye on the flying blighters.

And what is my license money really going towards, if not the monkeys?

We need answers. 

 

 

 

 

 

Edited by Tony1
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Stating the obvious.

The purpose of mooring lines is to restrain the movement of the boat so it stays where you want it to be.

Generally alongside a landing.

Mooring lies restrict the movement of the boat in an arc around their landslide attachment. An arc of a radius equal to their taut length.

Water movement is both horizontal more or less parallel to the bank but also vertical. Even limited vertical movement must be considered in mooring line arrangements as the forces constraining vertical movement rapidly become considerable trying to either hold boat up, or hold it down.

Lines at 90 degrees to the boat , breast lines,are great at holding it alongside but provide negligible resistance from for and aft movement and will quickly overload resisting  any vertical displacement.

Taking the bow line forward 30-60 degrees and the stern line aft the same amount is a really  good compromise to resist horizontal and vertical forces in all directions.  The bigger the angle the better at resisting fore and aft movement,at the cost of degradation of holding tight along side.

For every line taken forward, a line needs to be taken aftwards to provide the constraint in the opposing direction.

 

Sometimes bollard spacing  or overhanging a jetty dictates that the forward line cannot be taken forward (or the aft line cannot be taken aft)

In this case taking the forward line aft, 45 to 60 degrees aft and the aft line forward may be the best achievable, that is mooring by just a pair of spring lines. 

The boat will not hold as well alongside though, but  this can be very largely addressed if one of those springs is supplemented by a bow, or stern line at approximately the same angle, forming a mooring line triangle at one end of the boat.

 

Where vertical movement is siignficant, eg tidal areas all lines need to accomodate the expected vertical movement.,  A long pair of springs will contain fore and aft movement with little freedom for horizontal movement away from the quay. All lines then will always need to be long enough to accomodate the expected vertical movement. 

 

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