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05-06-2020, 15:43
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#1
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Registered User
Join Date: Dec 2016
Location: Somewhere in French Polynesia
Boat: Dean 440 13.4m catamaran
Posts: 2,333
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Oh no...yet another anchoring thread !
well sort of anchoring...more about swivels really
like a lot of people, our swivel is attached directly to the anchor ie anchor - swivel - chain
been thinking : modern anchors bury themselves very well (we have a SARCA Excel). thus when the boat swings on the anchor (with tide or wind), it seems to me likely that there will be a fair bit of bending force on the swivel, as the anchor is turned. even worse if the anchor is so buried it doesn't turn.
this would seem to be very bad for the swivel, which is quite likely the weakest point in the system anyway.
so i'm looking at putting some chain - 1-2m ? - between the anchor and the swivel ie anchor - shackle - chain - swivel - chain.
Any thoughts on this plan ?
where do most folk have their swivel attached ?
cheers,
__________________
"home is where the anchor drops"...living onboard in French Polynesia...maintaining social distancing
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05-06-2020, 16:32
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#2
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Registered User
Join Date: Apr 2020
Boat: Amel 53, Super Maramu
Posts: 428
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Re: Oh no...yet another anchoring thread !
Like all things sailing, the answer is "it depends." Some types of swivel are stressed by sideloading, and some are not. The Mantus swivel is attached to the anchor with a shackle, so it can not be side loaded. Those that have a "fork" connection to the anchor, can all be damaged by side loading, if sever enough.
This thread will quickly degenerate to a lot of name calling and arguments about the usefulness of swivels, but all the rest of it is puffery and smoke.
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05-06-2020, 16:40
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#3
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Registered User
Join Date: Aug 2011
Location: Lower Chesapeake Bay Area
Boat: Bristol 27
Posts: 10,425
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Re: Oh no...yet another anchoring thread !
My setup has been this way for the last 16 years.
PO's setup and it has worked for me in some very rough conditions for the last 9 years.
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05-06-2020, 18:33
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#4
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Moderator
Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 21,135
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Re: Oh no...yet another anchoring thread !
Chris, if you feel that you want to retain the swivel, just a few links of chain will suffice to protect the swivel from side loading. No need for the kind of length you were postulating.
I won't bore you by saying we gave up on swivels a decade or more ago...
How's life in Iluka treating you, and are bridge openings available with covid rules?
Jim
__________________
Jim and Ann s/v Insatiable II, lying Port Cygnet Tasmania once again.
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05-06-2020, 18:56
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#5
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Registered User
Join Date: Sep 2011
Location: Good question
Boat: Rafiki 37
Posts: 14,131
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Re: Oh no...yet another anchoring thread !
What Jim said (I seem to say that a lot ). If you think a swivel is useful, then just a few links between anchor and swivel will suffice.
This is how I ran my swivel setup for many years. I installed the swivel to address the chain twist problem. After a few years of use I concluded that it really didn't help, and introduced another possible failure point.
I've gone back to no-swivel for the past few years, and I still get the same amount of chain twist. No difference either way.
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05-06-2020, 21:22
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#6
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Registered User
Join Date: Dec 2016
Location: Somewhere in French Polynesia
Boat: Dean 440 13.4m catamaran
Posts: 2,333
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Re: Oh no...yet another anchoring thread !
Quote:
Originally Posted by Jim Cate
Chris, if you feel that you want to retain the swivel, just a few links of chain will suffice to protect the swivel from side loading. No need for the kind of length you were postulating.
I won't bore you by saying we gave up on swivels a decade or more ago...
How's life in Iluka treating you, and are bridge openings available with covid rules?
Jim
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re the swivel : ours is the fork type and so i think we'll add some chain to protect it a bit
interesting about giving up on swivels. we are having an argument with lewmar about wear to our 1 year old gypsy, and almost the first question they asked is 'do we have a swivel ?'. i got the impression the warranty might be void if not...
as regards life in iluka : the words 'heaven' and 'perfect' come to mind
we are having a mutual love affair with the baker think he is buying a new car on the extra income we have generated for him...
bridge is working as usual, and we are going up river on monday for a few weeks change of scenery
cheers,
__________________
"home is where the anchor drops"...living onboard in French Polynesia...maintaining social distancing
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05-06-2020, 21:44
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#7
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Registered User
Join Date: Jan 2011
Location: Cowichan Bay, BC (Maple Bay Marina)
Posts: 9,703
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Re: Oh no...yet another anchoring thread !
Quote:
Originally Posted by thomm225
My setup has been this way for the last 16 years.
PO's setup and it has worked for me in some very rough conditions for the last 9 years.
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Yeah, but he's got a CQR!!!!
I'm actually looking forward to anchoring threads now.
See, Covid19 hasn't affected me at all. :facep alm:
__________________
Stu Jackson
Catalina 34 #224 (1986) C34IA Secretary
Cowichan Bay, BC, SR/FK, M25, Rocna 10 (22#) (NZ model)
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06-06-2020, 00:51
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#8
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Moderator
Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 21,135
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Re: Oh no...yet another anchoring thread !
Quote:
bridge is working as usual, and we are going up river on monday for a few weeks change of scenery
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Good news, chris. Do stop in and say g'day to Gary, tyler, Sue and Al. they are working away on Al's new super cruiser... a Brazilian design, executed in glass, foam and vinylester. It's the first obvious wharf on the starboard side after you pass Mclean... about a mile or so. Big boatshed just up from t he bank. Really good people! And one hell of a shipwright!
Jim
__________________
Jim and Ann s/v Insatiable II, lying Port Cygnet Tasmania once again.
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06-06-2020, 01:17
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#9
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Registered User
Join Date: Dec 2019
Posts: 169
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Re: Oh no...yet another anchoring thread !
We were in a bay in Greece when there was a strong wind reversal, 3 yachts ended up on the beach they all had swivels.
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06-06-2020, 09:00
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#10
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Registered User
Join Date: Dec 2019
Location: Puget Sound, WA
Boat: Nauticat 43 ketch
Posts: 794
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Re: Oh no...yet another anchoring thread !
Quote:
Originally Posted by Mike OReilly
What Jim said (I seem to say that a lot ). If you think a swivel is useful, then just a few links between anchor and swivel will suffice.This is how I ran my swivel setup for many years. I installed the swivel to address the chain twist problem. After a few years of use I concluded that it really didn't help, and introduced another possible failure point.
I've gone back to no-swivel for the past few years, and I still get the same amount of chain twist. No difference either way.
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I agree with Mike. I've been using a Mantus swivel since it was first produced, and decided to experiment with not using a swivel when I got my Sarca Excel, which has a much longer shank and not much room for the swivel between the shank and windlass.
So far I haven't missed the swivel at all.
But, if using a swivel, be sure to use a big bow shackle on the anchor shank with the pin through the hole so the swivel can travel sideways without side loading. I wouldn't use the swivels that attach directly to the shank and tout their side loading ability.
The mantus swivel is a great design and comes with a strong shackle to attach to the anchor. I would still have another shackle on the anchor so you are attaching shackle to shackle for maximum range of motion.
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06-06-2020, 09:05
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#11
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Registered User
Join Date: Jan 2016
Location: Portsmouth, UK
Boat: Westerly Conway 36ft
Posts: 961
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Re: Oh no...yet another anchoring thread !
Non sequitur
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06-06-2020, 09:10
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#12
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Registered User
Join Date: Jan 2009
Location: Cabo Verde
Boat: Bruce Roberts Spray, 36' Steel Junk-Rigged Schooner
Posts: 1,245
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Re: Oh no...yet another anchoring thread !
Quote:
Originally Posted by chrisr
well sort of anchoring...more about swivels really
like a lot of people, our swivel is attached directly to the anchor ie anchor - swivel - chain
been thinking : modern anchors bury themselves very well (we have a SARCA Excel). thus when the boat swings on the anchor (with tide or wind), it seems to me likely that there will be a fair bit of bending force on the swivel, as the anchor is turned. even worse if the anchor is so buried it doesn't turn.
this would seem to be very bad for the swivel, which is quite likely the weakest point in the system anyway.
so i'm looking at putting some chain - 1-2m ? - between the anchor and the swivel ie anchor - shackle - chain - swivel - chain.
Any thoughts on this plan ?
where do most folk have their swivel attached ?
cheers,
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The Complete Anchoring Handbook suggests that swivels be mounted about a meter from the anchor to prevent lateral loads. Makes sense to me.
Edit - THe reason it suggests not much farther than 1 meter is so that the anchor can untwist itself while you are hauling it aboard.
__________________
"Civilized men are more discourteous than savages because they know they can be impolite without having their skulls split, as a general thing." Robert E. Howard
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06-06-2020, 09:15
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#13
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Registered User
Join Date: Jan 2007
Location: On board
Boat: Tom Colvin Gazelle 42ft
Posts: 325
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Re: Oh no...yet another anchoring thread !
Quote:
Originally Posted by Michael Cobbe
We were in a bay in Greece when there was a strong wind reversal, 3 yachts ended up on the beach they all had swivels.
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And? Did the swivels fail? Or were they 'plowing'?
Jim sv GAIA
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06-06-2020, 09:16
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#14
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Registered User
Join Date: Jan 2016
Location: Portsmouth, UK
Boat: Westerly Conway 36ft
Posts: 961
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Re: Oh no...yet another anchoring thread !
About the boats on the beach all having swivels i mean. Cant see how that would cause the problem. Unless you mean they all broke?
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06-06-2020, 09:30
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#15
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Registered User
Join Date: Jan 2009
Location: Cabo Verde
Boat: Bruce Roberts Spray, 36' Steel Junk-Rigged Schooner
Posts: 1,245
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Re: Oh no...yet another anchoring thread !
Quote:
Originally Posted by Clivevon
About the boats on the beach all having swivels i mean. Cant see how that would cause the problem. Unless you mean they all broke?
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This may be due to the misconception that you need a 8mm gauge swivel for 8mm chain - this is wrong, just as when you are sizing shackles for your tackle, you need to use the biggest size that will fit, as the more complex design is inherently weaker than welded chain.
Edit - for example, in the case of 8mm chain, you should use a 10mm shackle.
__________________
"Civilized men are more discourteous than savages because they know they can be impolite without having their skulls split, as a general thing." Robert E. Howard
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