Star-pattern Anchor System. Does it work? How to do it?

Bene505 · #1 (**permalink**) 08-12-2008

I have a new (to me) Beneteau 505. I'm planning to make my own mooring out of Danforth or plow anchors arrayed out in a star pattern, and then connected to a central chain. This technique is mentioned in Chapmans as withstanding a hurricane when most (all?) other boats with mushroom anchors were thrown up on land.

Does anyone have any experience with this type of anchoring system?

sailingdog · #2 (**permalink**) 08-12-2008

You're talking about a three-anchor mooring. It is heavily discussed in many of the books on anchoring technique. I would probably not use plows, but would use oversized Danforths instead, as they have much greater holding power if they don't have to resist a directional shift. However, it also depends a lot on what the bottom is made of.

Bene505 · #3 (**permalink**) 08-12-2008

I'll have to check the bottom to find out what it is.

I was thinking of using 3 to 5 anchors of 45 pounds each. Not sure if that's enough for a Beneteau 505. I'm trying to be cost effective without jeopardizing the sailboat. And the next anchor size up is really expensive. I have 500 feet of used chain that I bought - not the heaviest chain, mind you -- so having more (smaller) anchors would be more cost effective than having to go with heavier anchors and then buying new, heavier chain. If there's a hurricane on the way (and in Long Island we usually get several days warning), I'll probably pull the boat out. She's on a lake that's 3 miles long and 10 feet deep, and is very exposed to the wind right off the ocean.

sailingdog · #4 (**permalink**) 08-12-2008

45 lb. anchors are pretty small for a boat of that size, even if you're using three of them. More than three really doesn't make much sense, since you'll have to make the setup overly complicated.

If this is for a storm mooring, you really want the largest anchors you can get—and more small ones don't make any real sense... each of the individual anchors should be sufficient to hold the boat on their own...

I have a 28' trimaran and I'm using a 33 lb. anchor as my primary, and a 45 lb. anchor isn't all that much bigger and your boat is significantly bigger, heavier and with much greater windage than my boat.

Maine Sail · #5 (**permalink**) 08-12-2008

Check the local ordinances. Many towns/municipalities are now mandating certain types of moorings for their harbors.

There is not much better than a big mushroom in soft mud or a Pyramid mooring. In a harder bottom a large diameter flat piece of granite is great. Again if you have a soft bottom I would use a mushroom or pyramid.

Mine is buried so deep that the chain creates a funnel to the mushrooms eye and shackle that is about 3 feet deep. The head of my mushroom is about 6-7 feet below the surface of the bottom...

You can't always believe what you read in Chapman's because they rarely give you the full story. With moorings you need the right set up for the right bottom. A 50 footer, in my local harbor in Maine, would require a minimum of a 500 pound mushroom. Our local mooring guys however won't install much less than a 600-800 pounder for a 50 footer as the 500 pounds is the bare minimum.

Just so you have an idea of what you'll need for a permanent mooring the picture bellow is the chain and shackle for the mooring set up for my 36 footer!

For a 50'er you'll need a lot more than this. DO NOT skimp on your mooring set up!! 45 pound anchors on a 50 footer is like trying to fit Rosie O'Donnell into a size 1 bathing suit then sending her out in public!

sailingdog · #6 (**permalink**) 08-12-2008

Ummm...thanks for that really disturbing image Halekai... have to go get the Psychlorox.

Quote:

For a 50'er you'll need a lot more than this. DO NOT skimp on your mooring set up!! 45 pound anchors on a 50 footer is like trying to fit Rosie O'Donnell into a size 1 bathing suit then sending her out in public!

Maine Sail · #7 (**permalink**) 08-12-2008

Quote:

Originally Posted by sailingdog

Ummm...thanks for that really disturbing image Halekai... have to go get the Psychlorox.

Sorry but the thought of a 50'er on a 45 pound anchor seemed like seeing Rosie squeezed into a size 1... Not appropriate!

sailingdog · #8 (**permalink**) 08-12-2008

LOL... very true, but gotta wonder why you thought of that particularly disturbing analogy.

Bene505 · #9 (**permalink**) 08-13-2008

Thanks for the replies. Not sure what psyclorox is but get me some too.

The main thing is for her to stay put. If I have to buy new chain and more expensive anchors, then so be it. (And I'll have to check the ordances too. Didn't think of that.)

Halekai's chain looks a tad like overkill. I'm thinking to balance the tension strenght of the chain with the tension strenght of the anchors.

sailingdog · #10 (**permalink**) 08-13-2008

Overkill is really good on a mooring, since the chain isn't inspected for rust, damage and such all that often.

BTW, Psychlorox is mental bleach and used for getting things out of your head—like the image of Rosie O'Donnell in a bikini