Mooring pennant problems

[Stooriefit]

Hi All,

I keep my boat on a deep water swinging mooring. The boat is secured using a 3 strand nylon pennant. Both last year and this the pennant (new each April) has been fine up until about August when it has started to untwist about halfway between the bow roller and the water. I replaced this again only 2 weeks ago and yet again the untwisting has happened. The result is that I end up with 3 separate strands which if left alone would undo the splice. Any ideas as to what is going on? BTW all 3 pennants were professionally made by different reputable concerns.

Thanks

Alastair

 

[Poignard]

Hi All,

I keep my boat on a deep water swinging mooring. The boat is secured using a 3 strand nylon pennant. Both last year and this the pennant (new each April) has started to untwist about halfway between the bow roller and the water. I replaced this again only 2 weeks ago and yet again the untwisting has happened. The result is that I end up with 3 separate strands which if left alone would undo the splice. Any ideas as to what is going on? BTW all 3 pennants were professionally made by different reputable concerns.

Thanks

Alastair

Maybe a swivel would help?

 

[Stooriefit]

Already has a swivel. Thanks

 

[fireball]

Do you have a swivel between the pennant and the riser?

We also have a 3 strand mooring line (made by me) and the various lines have all stood quite a number of years use - never have they been untwisted.
We also have a chain running up - slightly slacker than the line, but attached to the same swivel (specked to the same as the riser) ... just in case!

 

[Stooriefit]

Do you have a swivel between the pennant and the riser?

We also have a 3 strand mooring line (made by me) and the various lines have all stood quite a number of years use - never have they been untwisted.
We also have a chain running up - slightly slacker than the line, but attached to the same swivel (specked to the same as the riser) ... just in case!

The riser is split in two by a swivel. So there is chain riser then a swivel then a rope riser to the float. My pennant is secured to the rope riser.

 

[Poignard]

The riser is split in two by a swivel. So there is chain riser then a swivel then a rope riser to the float. My pennant is secured to the rope riser.

Just a suggestion - but if the float is spinning [as they sometimes do in a strong current] maybe it could be causing the problem? Have you tried fitting a swivel in the pennant, or even dispensing with the swivel in the rope riser?

 

[Stooriefit]

Just a suggestion - but if the float is spinning [as they sometimes do in a strong current] maybe it could be causing the problem? Have you tried fitting a swivel in the pennant, or even dispensing with the swivel in the rope riser?

Thanks that might be an idea.

 

[Honey]

BTW all 3 pennants were professionally made by different reputable concerns.

I would check with the makers as I once had a similar problem with a rope in use on a windlass and it turned out that only "left hand rope" could be used for that purpose. I know this sounds like the old "glass hammer" con trick but rope can be made with either a left hand or right hand twist exactly like a screw thread. If your boat allways rotates in one direction with the tide, then it will need a particular twist to the rope unless the rope has a swivel. Your swivel has probably got one type of rope as a riser and the opposite twist as a pennant.

 

[jason -and the arguenauts]

Already has a swivel. Thanks

In which case the swivel isnt working properly under load. Its the only way that three strand can be unwound if you think about it.

Get a pennant made of multiplait. Or better still, chain.

 

[pete]

I think parsifal is right. The swivel will allow the buoy to turn with the riser but your boat will stop your mooring line from turning and start it unwinding in the middle between mooring buoy and boat . It has happened to my pick up buoy line which can spin in the water when my boat is not on its mooring. I use 2 X 2 ton lifting strops between mooring buoy and boat so this is not a problem.
Pete

 

[daviddub]

Mooring Pennants

I am aware of the type of pennant used by this person. On these moorings we do not recommend the use of thre strand nylon pennants. There are swivels above the riser chain and in this case it was found, on inspection, to be in perfect working order. The riser rope is braided nylon. The area has a fair amount of tidal eddy. When there is any tension on the riser it will twist before the swivel twists. If you use 3 strand nylon it will unravel before the riser rope twists or the swivel activates. We recommend the use of braided nylon pennants. With these we have no problems. We do not fit swivels into the pennant because, when the boat is off the mooring the weight of the pennant take the pennant down parallel to the riser and it twists around the riser causing horendous problems I am sure this will apply in other places.