Anchor ...well really a mooring....

[ianabc]

There's no room at the docks for 4 years!

I am considering anchoring our just launched 37 foot steel, 24,000 pound sailboat in the bay ( The bay is 1 Km across and protected from prevaling winds by a land spit.)

I was thinking of setting the gear down 80 m from the protecting land spit. (10 m deep at low tide)

Depth @ 10 m at low tide.

The Plan:
Using a good used 65 pound Austalian CQR variant and 100 feet of 1/2 inch galvanized chain plus 120 feet of 5/8 nylon spliced with stainless steel thimbles each end.

Risk ...esimated wind speed in winter of 60 knots max.


Silly idea or reasonably safe?

 

[jonlaw]

No problem with a mooring - but !!
I think your plan needs a little more work.
I would suggest two large anchors connected with a heavy chain, the heavier the better, what you can afford, around 100 feet, from the centre of this attach a swivel, then use at least half inch chain as a riser to the buoy, the length would be based on max depth at high water springs plus a few feet, ( ensure the riser cannot reach the anchors at low springs, it can snag and when tide rises snap, ) then you can use chain or a large mooring strop to attach the riser to the boat from under the mooring buoy. We have always used a rope strop fed through plastic pipe instead of chain to protect the boat, changing it every couple of years.
All shackles should be wired.

 

[Ships_Cat]

Not something I would do myself but if you are inclined would add that you should check any insurance policies. I believe that an insurer would class what you describe as your boat's being "anchored and unattended" in which case some (many?) either prohibit a boat being left such for other than short stays or require the boat to be checked every set interval (commonly every 24 hours).

John

 

[GMac]

Not a silly idea but could be tweaked a bit.

Firstly I'd follow Ships Cat advise and sus that.

How long do you plan to be there and any wave action?

 

[Blueboatman]

Hmm. A 12 tonne sailboat ,maybe with high windage,surging around in 60knots and mebbe a swell coming in and mebbe winds from differing directions.....Is there anyone who would sink a proper concrete mooring for you,if that is allowed?
Watch the chafe where the mooring comes onto the bow-I would want nothing less than a double chain bridle there,(chain for chafe)led over(and pinned so that it cant jump out of)the substantial bow roller and hooked over your steel Samson post.....
65 knots is close to cat 1 hurricane. No one secures an unattended boat with a theoretical 1km fetch on just one anchor,do they?

 

[Shanty]

Your proposed system sounds way too light to me. The mooring for my 3.5 ton 30 footer uses two anchors, one of which is heavier than your proposed single anchor.

The best starting point for an exercise like this is to see what other moorings are in the area. Find out what setup they use. If there are no moorings, why not?

Personally, I like the two anchor setup already mentioned, but that's because it works well in my area. Maybe something different suits your conditions - go with local knowledge.

 

[longjohnsilver]

Did you leave a 0 off the weight of the proposed anchor??

Wouldn't want to leave my boat unattended overnight on what you suggest, let alone permanently! Recommend you think again if you want to see your boat in one peice.

 

[craigsmith]

[ QUOTE ]
Depth @ 10 m at low tide.

The Plan:
Using a good used 65 pound Austalian CQR variant and 100 feet of 1/2 inch galvanized chain plus 120 feet of 5/8 nylon spliced with stainless steel thimbles each end.

Risk ...esimated wind speed in winter of 60 knots max.


Silly idea or reasonably safe?

[/ QUOTE ]Silly idea /forums/images/graemlins/grin.gif a "65 pound Austalian CQR variant"...? although that's over-weight for typical use it'll never be adequate for 60 knots etc unattended. Get a decent anchor.

No need for more than one, in fact it's a bad idea, lest they manage to foul each other, and if in tandem it also effectively reduces the scope of the primary. Since ease of handling and weight-on-bow are not factors, get a single large pick.

Depth: you need to think what it is at high tide, not low tide - low tide is best case scenario. Add two meters for high tide? And add another meter for bow-roller height above the water and you still get over 5:1 scope with your 220' of rode, which is rather good in that depth.

 

[oldharry]

I would go for 2 anchors laid across the bottom, with substantially heavier chain than half inch. And you should not waste money on galavanised for the ground tackle, it will wear through quickly in sand anyway.

Last mooring I laid was for a 24 footer in a fast flowing buit reasonably sheltered estuary: I had 2 anchors double the weight of the normal bower, connected by 100 ft of 2 inch chain, laid across the direcion of flow of the tise. A riser in the middle of 1 inch chain up to the buoy, followed by half inch galvanised chain to the boat. The riser was at least X3 the max HW depth. This held for the ten years I used it, and AFAIK is still in use.

Obviously for a heavy 37 footer, everything needs to be that much bigger.


Buty lots of s leave our boats on moorings of one kind or another, but never - not ever! - just o one anchor. If that shifts, so does your boat!

The 'normal' method is to use a heavy sinker, bedded well into the seabed, with chain at least twice, preferably three times the weight of the main anchor chain

 

[William_H]

Yes use 2 anchors set well apart on the ends of a long chain. The reason is so that neither anchor has to reset at each tide or wind change. ie one anchor takes the load only when wind or tide pulls in that direction. To be more thorough you can make it 4 anchors. This makes a far superior mooring than concrete.
The real trick is to get the 2 ancjors set at each end of the bottom chain. The easiest way is dive down and set them at the ends of the chain hoping they don't move far when digging in. You want the bottom chain between anchors pretty tight.(or at least with minimum slack) Any slack will allow the mooring and boat position to move at each wind tide change dragging the chain across the bottom.
You may be able to devise a method of setting the 2 anchors on sparate chains then joining the 2 chains together before rising. I mean like a ring slid or pulled down to the junction to effectively join them together on the bottom. good luck olewill

 

[GMac]

To much concentration on anchors there all. Its a system you want not a anchor with something off the back. It would not be hard to moor him well with NO anchor at all.

We don't know if he is planning on leaving it there a while or just a few weeks, it can make a big differance. Not enuff input to give good output yet.

Like Craig above who else is thinking the "Austalian CQR variant" means a SARCA? /forums/images/graemlins/smile.gif