Slack or tight?

chuns

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When moored to a marina pontoon (and particularly when some lively winds are expected) do you tighten all the lines up, so the boat hardly moves at all, or do you leave them relatively loose so that the boat can surge about a bit?

The reason I ask is that I tighten mine up, thinking to avoid snatch loads; and a neighbour said to leave them loose so the boat can respond to swell without straining the lines.

What is the consensus of forum wisdom?
 
What about leaving them relatively tight with one of these attached:

mooring_spring.jpg
 
I tighten them up to stop the boat bashing against the pontoon and scuffing topsides with the fenders; also to stop snatch loads on lines which are far more damaging than the steady pressure on tight lines. Also there is bound to be some movement of the slack lines around bollards, cleats and fairleads which will lead to chafe failure in time.
 
Well you know our berth of course, tail into the SW. We use rubber snubbers in the bow lines which allows some movement of the boat aft and away from the main pontoon. The stern breast rope is slack too. The forward spring line is set to stop the boat reaching the main pontoon. With this set up the boat can move easily backwards and forwards over a limited distance, basically determined by the amount of stretch in in the two bowlines rubber snubbers. We also have a second line from the outside centre cleat to the main pontoon which is set taught'ish and holds the boat most of the time away from ther finger pontoon.

We have used this same arrangement very successfully in visitor berths in St Malo (St Servan) in a NW gale and in La Trinite in a SE gale where the outside finger berths are very exposed and you also get wind against tide. In the latter case a wooden boat lost a mooring cleat which pulled out and flew three berths before it came to earth! We had rubber snubbers in both bow lines and also the stern line and had a reasonably peaceful but snatch and squeak free night! We carry snubbers made up for anchoring anyway, but also have a couple of others bought for the away berth situation, bought them half price at Beaulieu (well double price if you count the 'expenses' ).

Robin
 
RS is in Norway in a marina that is subject to some pretty hefty winds from time to time F9+. The locals all use bolt tight lines with rubber snubbers in line. Even with this arrangement RS managed to ride over the pontoon in a bit of blow last winter. The lines got tightened a bit more after that!

The snubbers are shaped like a small brick with 4 holes spaced at 2 inch intervals and the mooring line is threaded up and down through the holes. I shall be leaving them on the mooring lines permanently as I think that they solve the problem of what to do in a blow.
 
Yes

Thats what I do

Springs being tight prevent fore and aft movement which takes little energy but allow a twisting motion which absorbs considerably more energy moving thro water across line of boat.

Also because most boats are thinner at ends than middle help maintain a decent gap from adjacent boat.
 
I prefer all lines to be tight, particularly the springs to stop the fore and aft movement. That helps keep the fenders in their place ...
We tend to double up if there's to be a bit of a blow though...
 
Only one person has mentioned breast lines so far.

As most people tie up with just fore/aft lines and springs surely the first thing to do is to put breast lines on?

Just curious. I'm on a swinging mooring so it's not a problem for me!
 
I've set up my lines to hold me off the pontoon in most wind wind conditions, and to do this they have to be tight and I prefer polyamide (nylon) for stretch. Has worked for me over the last winter.
 
Ever see a ship berthed with slack lines? I haven't and I always berth with tight lines. If necessary I use a breast rope on the side away from the finger from amidships to the pontoon which, if tight enough will only allow the fenders to contact the finger in the biggest gusts. Yes the loads on the lines can seem quite high but only a fraction of their design load and there is no snatch.

Chafe is what must be avoided at all costs, a warp failure due to chafe is the most common cause of a problem other than fenders being too low and going under the finger when the boat heels. The breast line mentioned above reduces roll if the wind is on the beam away from the finger as it has to stretch if all the other mooring lines are tight. /forums/images/graemlins/smile.gif
 
[ QUOTE ]
I was told and no reason to disbelieve it, springs tight, bow and stern with a bit of slack.
That way, the boat can't surge but can rotate a little which helps to stop fenders riding up.
If the winds are strong, double up the lines.

[/ QUOTE ]Yep, thats my strategy too....
 
I've got 2 lines - one tight and one slack ... the tight one slackens off at slack tide and no wind ... hopefully the slack one will never tighten ... if it does I've lost my primary mooring strop!
 
Yup, I sometimes double up the warps as you describe. Once when I went away for a week to my surprise when I got back the primary warp (which had been in good condition) had chafed right through and parted... There'd been a nasty storm in the meantime. I was VERY glad I'd doubled up.

Since then I leave the warps tightish to stop her ranging around, but with a small amount of slack and preferably also with snubbers, because if too tight the warps can pull her hard into the pontoon when she starts bouncing up and down out of sync with the pontoon.
 
Hmm - don't think you quite got my post ... I tie off to a single point ... on a buoy ...

Fenders have an easy time on my boat! /forums/images/graemlins/laugh.gif
 
Ahhh!

Still, the principle of doubling up still applies.

On the same occasion two fenders were burst by the same storm. Luckily I'd also added a couple extra of those...

Incidentally it was in Brighton.
 
Hmm - any storm would find it exceedingly difficult to burst my fenders ... it'd have to get in the locker first! ...

We always double up - 1 rope strop ... 1 chain .. if it is that strong that the rope has broke (I keep an eye on any chaffing - none so far!) then I just hope the chain will hold long enough .... !
 
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