Mooring springs

[pessimist]

We are moving to our winter berth on a pontoon shortly and are considering stainless mooring springs to ameliorate snatch loadings. The confusing part is which springs to buy - we are a 36ft cat with a displacement of 5-6 tons. All the springs I can find expect a boat of this length to weigh considerably more. I'm assuming that over sizing the springs would potentially make them too "stiff" but under sizing could strain them. Any suggestions and/or suppliers.
Thanks,
Confused of Exmoor.

 

[cherod]

surely it goes on the weight , not the length ,, mine ( rubber ) are a bit oversized for my weight of cat ( 36' ) but never get any snatching .

 

[stuartwineberg]

check out this type of rubber ones on ebay. Excellent, cheap and dont make metallic groaning noises all the time. They are rated by mooring warp thickness as the rope weaves in and out of the compensator.

 

[ctva]

I’d stick to just the correct diameter of nylon or polyester which have plenty of stretch. I think only one boat in our place has them. We are a 5-7ton awb and use 14mm polyester.

 

[Rappey]

I’d stick to just the correct diameter of nylon or polyester which have plenty of stretch.

But then you come down to your nicely tied up boat to find its stretched so much the boat is now 4ft away from the pontoon?
The metal ones once a little worn in make hell of a racket.. The rubber ones look to be far better.

 

[NormanS]

The one time that I had (long story) to be berthed at an exposed pontoon, I borrowed a couple of old motor tyres, and used them to prevent jerking on the lines. Cheap (free) and cheerful, and did the job well.

 

[ctva]

But then you come down to your nicely tied up boat to find its stretched so much the boat is now 4ft away from the pontoon?
The metal ones once a little worn in make hell of a racket.. The rubber ones look to be far better.

Ok, Mr Pedant, ELASTIC. They stretch out and then back.

Of course if you are not using nylon or polyester even with the rubber or metal springy things…

 

[Rappey]

Ok, Mr Pedant, ELASTIC.

Haha,, i didnt mean it like that.. Maybe ive always had carp rope but ive always found it stretches out and never back over a period of time..

 

[harvey38]

12 ton MOBO and use 16mm lines through rubber snubbers, we sleep very well ?

 

[Clancy Moped]

How not to do it....

​

 

[ctva]

Haha,, i didnt mean it like that.. Maybe ive always had carp rope but ive always found it stretches out and never back over a period of time..

Cool, shows how difficult, even with smilies, to convey intent. ?

I can say that in 20+ years I’ve never had lines elongate through stretch like that. Quality of warp? Age?

On a side note, I do find it strange that many owners use old cast off ropes, usually static lines, for mooring having spent a fortune on a boat,

 

[Clancy Moped]

My set was similar to this, cap ended ones stops the spring from deforming, the baton inside the spring stops full compression and causing failure, and a safety chain.

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[Neeves]

We are moving to our winter berth on a pontoon shortly and are considering stainless mooring springs to ameliorate snatch loadings. The confusing part is which springs to buy - we are a 36ft cat with a displacement of 5-6 tons. All the springs I can find expect a boat of this length to weigh considerably more. I'm assuming that over sizing the springs would potentially make them too "stiff" but under sizing could strain them. Any suggestions and/or suppliers.
Thanks,
Confused of Exmoor.

Your displacement might 6t - but I guess you will be heavier. We have a 38' cat and our worst case - we would have 400kg of water and 200kg of diesel + plus a desal unit, deep freeze, inverter, liferaft etc etc.

Is the intent to leave your cat unsupervised and unvisited for its time in 'layup' of might you visit.

On a side note, I do find it strange that many owners use old cast off ropes, usually static lines, for mooring having spent a fortune on a boat,

I do find it strange that the suggestion might be that you have spent a fortune on a yacht and are looking for devices to keep it safe over half the year....?

Take care, stay safe

Jonathan

 

[geem]

But then you come down to your nicely tied up boat to find its stretched so much the boat is now 4ft away from the pontoon?
The metal ones once a little worn in make hell of a racket.. The rubber ones look to be far better.

It my depend on the type. My s/s ones are silent but they have rubber inserts where the springs would bottom out