Laying a mooring

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I want to lay my own mooring for a 22foot powerboat.
Can anyone advise what I need to get please?
The seabed is a basically muddy......I'm thinking a couple of old car engines chained together.....what do you think.
I've heard that there is a "screw" system somewhere...any comments.....
Oh, by the way there is no tide to worry about, but it can get windy!!! (the boat is in Antigua)
Thanks in advance
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What about a couple of truck wheels from the scrapyard. Dig 'em in, chain 'em together, then fill 'em with mud. Luverly job!


exactly what i did when doing a friends mooring on the seafront. have held a 35ft boat in all the latest wind
 
Your biggest problem would be putting dissimilar metals together e.g. cast-iron engine blocks with galvanized chain. Over time, the chain may waste-away. In the Bahamas (equally windy!) I have seen ground tackle of all sorts including the method you describe. My friend's sailboat was almost lost because of the chain corroded away until some of the links resembled wire!

My method would be to embed into the wet concrete filling a 55 gallon oil drum, a 12mm dia stainless steel rod (say a metre or more in length) which has been bent into a 'U' shape with splayed out ends. Thread this through several metres of heavy s/s chain. Avoid using a shackle for the connection, these sometimes work loose and let go! Onto this s/s chain, connect regular galvanized heavy chain and a 'moused-on' galvanized shackle BUT make sure you can lift and inspect it at least annually for corrosion, etc. Then rig the usual mooring buoy to the end of this chain in the normal way.
 
I got our local boatyard to lay me a mooring (insurance insisted on a professional job!). They got 2 big Danforth Anchors which they joined together with 15m of heavy chain. In the middle of the chain they attached a swivel and a riser to the mooring buoy. From the buoy there are 2 attachments to the boat (belt & braces!). The anchors were dug into the mud to a depth of about 2ft. It seems to have worked very well for the last 7 years with my 21ft lift-keel sailing boat.

Judging by the rather sudden coming to a halt that I often get when working my way up my Creek to the mooring, many people use the big lump sitting on the bottom principle to lay a "mooring". Firstly they drag all round the creek at the next big high tide, and secondly, unless you have bilge keels they're really nasty things to dry out on!

Please do the job properly!
 
I laid a mooring into sand last year for a 40' masthead rigged sailboat displacing 8.5t.
Go to a scrap yard and get the biggest lump of iron that you can handle. In my case, I used the counter-weight from a scrapped fork lift truck (2 of them).
The heavy non galvanised (the galv gets scrubbed off on the bottom) chain was attached to these by looping it through the hole in the back of the weight and a "hammerlock" shackle to join it to itself. Hammerlocks are use by trawlers to attach their nets and don't suffer from the pin un screwing. Seizing wire always works loose or corrodes and shackle pins always come out when you don't want them to (or get stuck when you want to remove them).
Where the two chains ( one from each weight) join together another hammerlock and a swivel are used to connect the riser chain. This can all be reached at low water to allow me to check the condition of everything. The riser is a smaller weight galv chain with another swivel just below the float.
I use two nylon pickup lines to secure the boat to the mooring. The nylon reduces the snatching that you get with chain/wire and with plastic pipe over it, has plenty of chafe resistance. In my case the bridles are long enough to reach back to the genoa primary winches as a) they are the strongest attachment point on the boat b) the long length of nylon has more give in it.
Go as large in size as you can without compromising ease of handling. If there are other boats around you, check the lengths that they use for the riser so that all the boats move in a similar way.
I'd avoid using old wheels (old railway carriage wheels or similar) as these can work themselves out of the mud and skip across the surface if vibrated/pulled hard enough. If someone can weld up a mushroom anchor for you, that would be another alternative.
 
I use the wheel method. Heaviest wheel and tyre you can lift safely. Bury it as deep as possible, dome side up with the upper side wall cut out. The combination acts like a suction cup.
Concrete is suprisingly light when immersed, compared with the backbreaking weight in air.
Attaching chain is always a compromise, Moused shackles, welded bar whatever is available but there is usually not a lot of movement at the lump end. I weave old rope through the links to reduce the grinding action when metal and mud work together as all swings.

Here is one spec I found a couple of years ago on the Harlow & Blackwater sc site (link now gorn....)
SINKERS (Minimum)
2 cast concrete sinkers, 51cm diam x 15cm thick ( 3 sand, 2 shingle, 1.5 cement ). Each have a central steel hoop 8mm diam, shaped to ensure good anchorage in the concrete. These must be cured for 2 wks before being sunk at their allocated position at a minimum depth of 46cm into the clay. (NOT silt).
GROUND CHAIN (Minimum)
Connects the sinkers 3.5m apart. Chain to be 13mm diam long link chain, self colour and fastened to the sinker loops with large shackles.
RISING CHAIN (Minimum)
Connect the first 3.5m of the riser, 13mm diam, long link chain, self colour to the centre of the ground chain with the largest shackle possible. Fit a swivel
suitable for 13mm chain, to join the remaining chain onto the second section. It must comprise of 10mm (3/8") or 13mm (1/2") long link chain, self colour.
MOORING LINK (Minimum)
A mooring link to attach the riser chain to the mooring post on the boat should comprise a length of 38mm diam Nylon or Polypropylene rope DOUBLED, attached to the end of the riser with a large thimble. With both ends of this link cleated to
the boat, this achieves a 2x safety factor.
BUOY
Yellow or Orange secured to the riser chain thimble with a 2m length of substantial rope line. It must be able to support 2m of 10mm
(3/8) chain and should show at high tide.
 
You could try talking to these guys in Antigua ;
FALMOUTH MARINE
English Harbour Tel 460 1154
SEA PONY
English Harbour Tel 464 3164

I think both of them lay moorings - I have seen a workboat belonging to one of them (cant remember who) in English Harbour, and it appeared to have equipment for putting screws into the bottom.

If the bottom is muddy, I am guessing that this is in English Harbour or St Johns harbour (?).

Its not a very big boat - I would just use a couple of anchors on a bridle - if you use 3/8" chain that should last a long time.

Our mooring (in hard sand, good holding) here for a 35' sailboat is a 40 lb Danforth and a 45 lb plough on a bridle, with 3/8" chain on the bottom, 15' of ships anchor chain where it comes off the bottom, and 1/2" riser chain to the buoy. She has sat through pretty strong winds on this set up.
 
Flat board about 1.5m square ..... one large truck tyre ...... plenty concrete mix ....... large commercial chain about 1" or more bar link (thats big ground chain stuff !! check dredgers etc. when changing out derrick chains etc). about 3ft long.

Place tyre flat on board with chain flaked under and out to sides. Centre of chain lifted up by one link by holding bar above tyre to form a connecting link.
Pour in concrete mix whacking tyre a lot to make mix flood out into walls and inside tyre .... keep adding mix till you have filled it completely ....

You should now have a concrete filled tyre with serious chain embedded into it ... the links full of concrete etc. that literally will not budge for years ... and good connection link in centre top.

The size of chain is good enough to last a considerable period even though concrete leads to steel tending to corrode together ... you could if you want black tar the links ... but honest - steel pipelines are laid across countrys with only a slight rust surface for concrete to key to ... last years ...

Thats my contribution to the thread anyway ... of course another way is to beg borrow or steal a large anchor that has come of a significantly larger vessel and use that ?
I'm talking .5 - 1 ton job ?
 
Concrete on it's own is not very useful - it almost - but not quite - floats underwater! Where concrete blocks are used for moorings they tend to be really big - 3 tons to 8 tons were the sizes used in Hong Kong for yacht moorings (where you also get big winds at times).
 
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Concrete on it's own is not very useful - it almost - but not quite - floats underwater! Where concrete blocks are used for moorings they tend to be really big - 3 tons to 8 tons were the sizes used in Hong Kong for yacht moorings (where you also get big winds at times).

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I can send you the specs on various moorings used in UK specifically with concrete sinkers .. average for boats up to 30ft being about 4ft diameter and about 1ft thick.
Having held such of the bow IN the water to "drop" in alloacted space many times - I can hinestly say that my 25ft Motor-sailer used to sit quite seriously bow down with that lump hanging IN the water. The ground chain was flaked along the deck so did not create that serious trim by head.

The original post also said mud bottom ... ideal as the concrete sinker as I describe will bed flat and create a suction under that increase its holding seriously .. possibly double. Where I have had to lift blocks by use of winch and tide ... my above boat has had its stem literally inches only freeboard before the sinker "gives up" and frees ...

With possibility of strong winds and lets be honest the location is subject to tropical storms etc. - then size should go up dramatically ... possibly 2x 3x the size ...
 
there is a few dangerous suggestions on here namely that stainless steel is suitable as ground chain and that concrete nearly floats in mud, take such advice with a pinch of salt.

round here we have 10 mtr tides and lots of wind, as others have said get a big lump of concrete or steel, use 1 1/2 inch ground chain, 12 mm riser chain and at least 24 mm rope, multiplait is best as it does not unwind.

easy and safe
 
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Your biggest problem would be putting dissimilar metals together e.g. cast-iron engine blocks with galvanized chain. Over time, the chain may waste-away. In the Bahamas (equally windy!) I have seen ground tackle of all sorts including the method you describe. My friend's sailboat was almost lost because of the chain corroded away until some of the links resembled wire!

My method would be to embed into the wet concrete filling a 55 gallon oil drum, a 12mm dia stainless steel rod (say a metre or more in length) which has been bent into a 'U' shape with splayed out ends. Thread this through several metres of heavy s/s chain. Avoid using a shackle for the connection, these sometimes work loose and let go! Onto this s/s chain, connect regular galvanized heavy chain and a 'moused-on' galvanized shackle BUT make sure you can lift and inspect it at least annually for corrosion, etc. Then rig the usual mooring buoy to the end of this chain in the normal way.

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Sorry ... NEVER EVER mix metals particularly stainless and galvanized ... In fact you would be better using black iron than the mix you suggest.
 
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NEVER EVER mix metals particularly stainless and galvanized

[/ QUOTE ] Or stainless and plain ungalvanised steel for that matter.

Stainless steels are in a similar position in the "Galvanic series" to copper and its alloys (that's why copper ferrules can be used on stainless steel wires) so is incompatible with plain steels or iron, galvanised or not.


For what it is worth our yard uses concrete sinkers with a length (about 12 ft IIRC) of 1" chain cast in and reinforced with steel bars The sinkers are made as broad squat flat topped pyramids. At least 1m sqaure I should think but only about 25 or 30 cm deep deep. That gives them loads of suction in the mud and makes them a bit less of a hazard than other shapes if you sit on them at low tide.

Perhaps neil_s will describe the one he made for his Super Seal.
 
just wondering about the logistics of laying concrete sinkers ;lorry engines or lorry tyres. how you get them onto and then into the water.??
my boatyard has to use a specialised barge thing and the sinkers are craned onto it from the side.
 
i floated out half a ton of steel under my knackered 9 foot dinghy, i towed the dinghy to the desired spot, tied a hacksaw to a broom handle and cut the rope that supported the weight when i was in position.

at no time was i on the dinghy with the weight, i used my other dinghy to tow it, all went easily and safely
 
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How do you go about lifting a 55 gallon drum of concrete?

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Pay for a barge to place it.

It's one of those subjects. Ask 20 guys and get 20 different answers. Basically, do what you do and be happy with it. Peleicanpete -Out!
 
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