Swing mooring

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Adrian62

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My boat new to me will be going in the water at the end of the month to a swing mooring which I have to supply my own connection to the buoy . Just want to check that I will be doing it correct as not done this before . I am thinking from the buoy it would be shackle to the buoy then a swivel shackled to a length of chain to connect to the cleats on the boat .plus a pick up rope with buoy . Using 8 or 10 mm chain . Does this seem about right .Boat is a 29ft westerly . Thanks
 
There might already be a swivel in the buoy or riser, in which case adding a second one is unnecessary and an additional point of failure.
Personally I prefer a rope strop, rather than a chain. I use the biggest that will fit the bow roller, with hose as chafe protection. You might want a slack chain as a failsafe, although sometimes in my experience having more than one strop causes twists and is more trouble than it's worth.
 
Kelpie said:
Personally I prefer a rope strop, rather than a chain. I use the biggest that will fit the bow roller, with hose as chafe protection. You might want a slack chain as a failsafe, although sometimes in my experience having more than one strop causes twists and is more trouble than it's worth.
Click to expand...

I too preferred a rope strop between buoy and bow, until it was comprehensively shredded in one stormy night and my boat became and insurance statistic.

You definitely want that slack chain as a failsafe, especially if it is run inside a piece of rubber/plastic pipe to stop it damaging your boat. This will enable you to sleep well on a stormy summer night...
 
3 Strand Nylon Rope - Mooring Strops

These guys are worth a look. As are are securefixdirect.com (search for swivel eye jaw if you want to use a combined swivel and shackle)
Both are a fraction of the cost of the usual suspects. Just be careful to look at the dimensions as well as the ratings as you need a pretty large fittings to go over the thimble if you go down the chunky rope strop route.
 
It all depends on how exposed your mooring is. I prefer chain for security or use rope and slack chain. Also, keep the strope short between buoy and bow roller to avoid the rope getting twisted when slack water.
 
I used twin rope strops the first time I had a swinging mooring and it was, to put it politely, a nightmare. However, we didn’t keep the mooring long before we departed for the Med.
I now have a small project boat which I’ve kept on a mooring for the past few years and I’ve always used chain straight from the buoy, over the anchor roller to the forward cleat. It’s simple and strong. Small pickup buoy on a decent length of rope enable me to pick the mooring up from the cockpit coaming and walk forward to the bow, pull the chain up and fix it in place.
Having done both rope and chain, I don't see the problem with all chain but do see the chafe problems inherent in the rope answer. Bit of matting to protect the deck if needed and that’s it.
 
Chain or rope should be connected to the chain under the buoy. One mooring operator here uses large rope strops on its moorings, another uses 10mm chain.
The chain needs replacing every year and rotated every 6 months.
I had many chains on a16ft boat and they don't last as long as you would think. Had a rope stop for 5 years and its still going strong.
 
duncan99210 said:
I used twin rope strops the first time I had a swinging mooring and it was, to put it politely, a nightmare.
Click to expand...

Why a nightmare, was the swivel not working?

I've had twin rope strops for 25+ years and never had a problem with them, won't have chain. Changed from nylon to polysteel a few years ago and they last much longer.
 
A rope strop is fine, if you eliminate chafe. That means a lot of monitoring when you start out.
Swivels will be needed in some locations not others.
Shackles are a high risk of coming undone. Do not underestimate this, the combination of vary loads and continuous movement will undo things.
A lot depends on the type of buoy and how it's rigged. A short strop to the top of the buoy works best here. That obviously means you must check and trust the integrity of the rope through the buoy.
Copying what others do locally is a good start.
In a gale, you may see some boats lying quietly, while others thrash about. If you can work out the differences, you'll know what works for your boat, on your mooring.

Having back-up strops or chains risks tangles which can cause high loads on things. If you go this route, I think you need to check the boat every day or two until you know it doesn't twist up the mooring due to tides turning.
Swivels underwater quite often decline to rotate in real life.

It's important to consider wind against tide, which will try to push the boat over the buoy with potential for damage to the bow area.
 
I get 2-3 years out of a rope strop. I use 32mm polysteel, multiplait, with a length of reinforced clear PVC hose for chafe protection at the bow roller. It is this hose that has failed on my previous strops, it goes brittle in the sunlight and eventually breaks at the chafe point. You can simply slip it down the rope a few inches to cover the vulnerable area, then go and make your new strop.
I actually just made my new strop yesterday... this year I am putting a bit of layflat hose over the top of the clear PVC, I hope that will delay the UV degradation.

I like rope because it doesn't leave rust marks, it lasts basically forever if protected from chafe, and it has a bit of 'give' in it to help absorb shock loads.
 
The less shackles etc you have connected between the cleat on the boat and rising chain the better - they are one of the main failure points. I would recommend always having the rising chain continuous and directly attached to the deck cleat. A strop is then attached to another cleat and then shackled to the rising chain, so that the strop takes the strain ( and allows a bit of give) but the chain is a backup in case the strop should chafe through in a blow. Some form of anti chafe should be used such as threading the strop through a thick plastic hose or a device made for the purpose such as Spiroll Rope Protection | Rope Protector.
Opinions differ on the use of swivels - our club doesn't use any and we get very little trouble with twisted chains - others swear by them! It very much depends where you are mooring,tides etc so probably best to see whether other boats immediately near you need them or not. They are another failure risk.
Our club use rising chains which are reeved through the ground chain ( no shackle). This is possible by the fact that there is a larger link at the end of the chain through which the rest of the chain can be reeved.
I don't know what size your rising chain is but I would have thought it should be 12mm. I use a 10mm chain on my 1200kg boat.If you attach a smaller diameter chain which is less than the main chain, and take it onto the boat then you are creating a weaker point.
Some people use a pickup buoy attached with a long rope to the chain - others use a support buoy as well -depending on the weight of chain and depth of water at your mooring. A short length of chain from the support buoy, can be shackled onto the rising chain - in this way there is no break in the continuous rising chain to the boat.
 
Taking the chain riser all the way to your cleats means it can't be very chunky. It's a trade off between reducing the number of shackles, and having a stronger and longer lived riser.
I use a 19mm chain riser, got five years out of the last one. The shackle connecting it to the strop is easily inspected and replaced.
This year I am trying out not using a swivel- I need to drop the mooring every month or so to let the twists out.
 
Kelpie said:
Taking the chain riser all the way to your cleats means it can't be very chunky. It's a trade off between reducing the number of shackles, and having a stronger and longer lived riser.
I use a 19mm chain riser, got five years out of the last one. The shackle connecting it to the strop is easily inspected and replaced.
This year I am trying out not using a swivel- I need to drop the mooring every month or so to let the twists out.
Click to expand...
Yes, I would agree - I'm lucky that a 10mm chain runs over my bow roller perfectly so I don't have a problem, and as my boat is relatively light, 10mm is adequate. It usually lasts 3 years providing I winterise the mooring using a buoy with 10metres of 6mm chain connected to the end of the rising chain. The rising chain is then on the seabed for the winter with little wear.
 
I used 3 rope strops .... each one connected to different point on the riding chain. First strop (main one and as large as bow roller can take) to the main mooring samson post .... second and third lighter but still each sufficient to carry boat load if necessary ... one goes to a mooring cleat and other goes to another cleat or as in my case a sailboat - to the mast base.

Second and third strops were slightly slack so main strop carried the boat.

I never had any problems of tangles .... each strop had a light line lightly tied to the pick-up buoy so on pick up - all 3 were at hand.

Why 3 ? I could have been fine with 2 ... after having seen boats go walkabout through the moorings ... damaging others on their way - I was never going to be that boat !!
 
Just as an example of minimum mooring reqt's as per Langstone Hbr .... this was 1990's and I do not think it has changed since then ...

[URL=https://s6.photobucket.com/user/nluther/media/superanne/Langstmoor_Page_3.jpg.html][/URL]

The tidal range experienced on the Tudor mooring I had was about 13ft springs .....

There are a couple of points that I have followed after incidents involving my boats over the years :

1. NEVER use BOW shackles .... only use proper sized D shackles. I had a large Bow shackle on a mooring at Farlington Marshes and in a storm - the bow turned to have all loads on the sides .... that shackle parted and opened out ...
I used to carry that shackle in the LandRover to show people just how much force can be exerted on a mooring ....
2. Having rescued a wayward Seamaster 23 that broke its single strop in Langstone ... and brought back to club area ... I was glad I used more than one strop for swinging moor.
3. Harbour reqt's are a MINIMUM to use - in chain / sinker size - but not good idea to increase scope as you may create a boat banging situation when one swings and another swings differently ...
4. Never use stainless steel in the mooring - best is galvanized or black iron. That way you can visually see the wastage as it corrodes. I know of some Commercial Mooring Layers that make this mistake ...
 
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