Mooring buoy attachment to riser chain

[davidbfox]

My mooring on Windermere has lost its buoy. Happily the boat is still attached to the riser chain.
When replacing the buoy, I would welcome advice on the best arrangement for attaching the buoy and the strops to the riser chain. Would you recommend:
A) attaching the buoy to the last link on the riser chain, with the strops shackled a couple of links below?
B) attaching the buoy the last link and the strops to the same link?
C) attaching the strops to the last link and the buoy a few links down?

And in each case would you use a swivel where the pair of strops attach to the chain?

We currently seem to get a lot of twisting on the strops.

Thanks in advance.

Dave

 

[Ceejay]

Starting from the bottom. Riser chain, then shackle on to bottom of swivel, then shackle from top of swivel on to mooring buoy. The strop would be attached normally by some means to a point above the swivel.
CJ

 

[sealegsjim]

I agree with Ceejay about the tackle. I have a decent mooring bouy a couple of years old with new swivel and chain strops which I assembled for my swinging mooring on Ullswater. I am now in Windermere Marina so do't need it. It's yours for £30. PM me if interested. I will be over at Windermere next week sometime

 

[davidbfox]

Thanks as always for advice and practical help.

 

[Seajet]

Remember to ' mouse ' ( wirelock ) the shackles with monel seizing wire.

The swivel is almost always the weakest link so make it as big as possible, bearing in mind the shackles having to fit both it and the chain; galvanised shackles are cheap and always come in handy so if not able to measure beforehand a few of varying sizes might be an idea, saves a trip back to the chandlers.

 

[KAM]

Not sure if anyone answered the original question but I have the same problem. At the moment my strop has been attached (by the mooring contractor) to the top of the swivel. The flotation buoy is also attached directly to the top of the swivel. The strop is part chain and part rope this means that the shackle and thimble which join the two chafe on the floatation buoy. I would have thought that the strop attachment ought to be above the swivel but about 300mm or so below the floatation buoy to avoid chafing. This must be a common issue. Can anyone point me to an authoritative source of information on this.

 

[the_branflake]

My mooring on Windermere has lost its buoy. Happily the boat is still attached to the riser chain.
When replacing the buoy, I would welcome advice on the best arrangement for attaching the buoy and the strops to the riser chain. Would you recommend:
A) attaching the buoy to the last link on the riser chain, with the strops shackled a couple of links below?


Dave

Hello,
Firstly I would just like to point out this is only from my own very limited experience but my setup is like option A. I'm also on winderemere (Thompson Holme south). On my mooring the buoy is near the end of the chain and the strops have a shackle each to the chain a little down from each other. I don't find mine gets tangled very much so I've not changed it.

My reasoning is on Winderemer the boats I see the wardens towing in always seem to have both strops and the buoy still attached to the boat, but that one shackle has let go and the boat has gone on a day trip.

Best,
Mat

 

[William_H]

Wear of iron shackles and chain is the biggest problem. The interface between surfaces develops rust as normal however this protective rust layer is quickly worn away by movement so more rust develops. Hence you get rapid wear on the mating surfaces of shackles and chain. The only answer is frequent inspection and starting with very large sized components. I have had success with stainless steel components it shows no sign of wear after several years but people say it is susceptible to crevice corrosion in salt water. Any meeting of stainless steel and iron seems to be really bad wear on the iron.
A swing mooring must have a swivel because boats will rotate around the mooring winding up chain or unwinding rope and splices.
Regarding the question of where to attach the buoy. It doesn't matter much. good luck olewill

 

[Seajet]

Not sure if anyone answered the original question but I have the same problem. At the moment my strop has been attached (by the mooring contractor) to the top of the swivel. The flotation buoy is also attached directly to the top of the swivel. The strop is part chain and part rope this means that the shackle and thimble which join the two chafe on the floatation buoy. I would have thought that the strop attachment ought to be above the swivel but about 300mm or so below the floatation buoy to avoid chafing. This must be a common issue. Can anyone point me to an authoritative source of information on this.

Not exactly authorative, but I've worked on the half tide moorings at my club for 35 years; we used to have a riser chain going straight from the swivel ( say halfway down ) to a pickup buoy.

A few years ago we changed to permanent floating buoys, the swivel is directly on top with the pickup buoy attached to that by chain.

I must admit I wasn't keen on having the swivel in this position to start with but it seems to work, and an advantage is the swivel doesn't go into the mud to pick up bits of stone, shell etc and jam or wear.

The floating buoys can be a pain clonking alongside the bows all night, the setup was the idea of a local who doesn't consider sleeping on the boat on the mooring, but a lot of us do.

The setup you describe with the pickup separate to float buoy and attached below the swivel sounds very wrong to me, seems the swivel is only protecting the floating buoy !

 

[KAM]

Sorry I probably did not describe it very well. The pickup and floatation buoy are both directly above the swivel. My thought was that the swivel ought to be a bit below the floatation buoy (with the pickup still above the swivel) to prevent the pickup chafing the buoy.

 

[aquaplane]

My current mooring has the swivel at the bottom of the riser. The buoy is attached to the top and the strops are attached to different links below the top one, just so that wear is on different links.

The one mooring of mine that failed was in much deeper water and it was the swivel that failed.

I have replaced my riser but it's only in 6 feet of water so I could get all of it to the surface and shackle directly onto the heavier chain that sits in the mud and doesn't seem to rust or wear like the rest of it does.

At this time of year the water is clear enough to see my block, I should really get the mask on and go down for a look.

 

[lw395]

If the swivel is on the bottom of the buoy it can be inspected more easily by attaching a tackle to the chain below it and capsizing the buoy.
If the swivel is in the mud it may either seize due to grit in it or wear.
With a mooring where a swivel was critical, I found a through rod buoy with the swivel above it best for my boat, in that location.
I expect different solutions will be better in different circumstances.
Obviously anything that will let your boat free if it breaks must be totally trustworthy.
Rather than rely on mousing wire for shackles etc, I replaced shackle pins with bolts and used locknuts, drilled through and pinned.
The pro's will weld shackles.
I also added a good drop of Loctite. Using a big spanner, I was able to undo stuff 2 years later to change the buoy.
Inspect frequently until you are sure you understand how fast things corrode in your location!

 

[ffiill]

My experience is that if you place the swivel before the buoy there is a tendancy for the buoy to get itself wrapped around everything .
I am just putting in a new mooring block and my buoy will be attached to the riser;then the swivel.Mind you mine is really heavy duty stuff with the swivel being 3/4 diameter and rated at one ton.
All my shackles on the bottom are welded and those on the surface are through bolted then a nylock nut is added.This both double locks the thread and cannot turn itself.
I find this far better than split pins because its quite easy ro slightly compress the jaws of the shackle causing that neatly drilled hole not to fit without back screwing the nut which of course defeats the object of the nut.
Oh yes I moused my shackles on my last mooring and after about two years within the space of six weeks everyone dropped its pin.
The first time my boat was retrieved whilst gently heading down Loch Duich towards Eilean Donan Castle on the outgoing tide.
The second time it was just happily floating in the bay at the head of Loch Duich and the third time the same!
Rubbish Chinese shackles did not help!

 

[davidbfox]

Thanks everyone!
Dave