Mooring Advice (in salt water)

[Rannsachair]

Can anyone offer any advice on moorings?

I thought it was simple - take one redundant steel valve block weighing 60 Kg, attach a large galvanized eye , a length of chain, some stout rope and a buoy. Worked for a year - then checked it to find my galvanized shackles have almost rusted away!

Do I need to do everything in stainless?

Do I just replace everything except the buoy every year?

Do I get a mushroom and lift it out over the winter?

I only use my mooring when I am on holiday with my boat - typically 4 weeks max per year. For weekends I just take the boat in and out the water.

Any advice appreciated - I would hate to think of the boat drifting off the mooring....

[Ali]

My old mooring for the my 18ft Dory uses a Fish box full of concrete and steel as the anchor. Attached to that is 3m of heavy chain and then 4m of heavy polyprop. All shackles are Green Pin Certified type as they do not corrode as fast, normal Galvy shackles from the chandlers disappear in no time. On my new mooring it is baically the same set up except I have two chain legs to a stainless swivel and then 4m of chain and then4.5 of polyprop. Again all shackles are greeen pin certified type and the swivel between the rope and chain is stainless. Have attached two anodes to the chain that spends most of it's time out of the mud, teh old boys reckon it is the best to stop corrosion of the riser.
Hope this may be of some help.
Ali.

[Garygee]

Hi Ali

Not much experience on RIB mooring but had a swinging mooring for years on a 28 foot yacht

Dont use stainless, stainless needs oxygen to stop corrosion and the section which sinks onto the mud will corrode very fast.
Also dont mix galv & stainless as it causes electolitic corossion (Unless to isolate with a nylon eye)
Chain below the sand last for years but above needs at least checking every season, more if you use thin chain.
I would recomend at least 3/8" chain then a nylon strop/20mm rope for the pick up.

A lot also depends on the size of RIB and how exposed it is.

The type of anchor depends on the bottom. If its mud or sand any big heavy weight will do, but if you dry out watch out for your boat coming to rest on the weight till its fully sunk. I have used a cut off 56 gallom drum, cut about half way, fix your chain to some heavey metalwork inside, fill with as much metal as poss them finish with concrete.
Also you can forget trying to lift the weight to check the chain, they dont come up easy in mud.

If you are only going to use it for 4 weeks a year i would be tempted to buy a mooring anchor, some chain and lay it when you need it then take it up. Make sure you fit a good tripping line as it will take some pulling out. (attach a few 5 gallon drums at low tide and let the water do the work!!)

Also make sure you fit a swivel in line and "wire the shackels" but dont use copper wire, I use heavy plastic cable ties or you can use galve coat hanger wire.

If yo want more info drop me a e-mail

[batfalcon]

I use a 15 kg Danforth with 10 m of stainless 1 inch eye chain attached to a buoy. I use to carry all this equipment wherever I go and use it under certain conditions. When I am on my standard mooring site I use a conctete block (which I found ready) about 200 kg with a 5 inch eye chain which in turn is attached to an 1 inch eye chain and then to the buoy. The small chain reacts as an absorber to the shocks and the heavy one never moved from it's place. I suppose that if I never had the concrete block the boat should be as steady as she is now.