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03-08-2009, 22:02
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#31
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Registered User
Join Date: Apr 2008
Location: SF Bay area at present
Boat: Mason 33 and a Nordic Folkboat (wooden)
Posts: 172
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WOW - I *do* feel like a knowledgeable punter. This is a truly wonderful resource for excellent info. WHen I bandy my CF gained knowledge around at the chandlery, esp as a woman, they look at you REALLY sideways. It is fun. Many thanks.
SO -- last question all about chain (and I will keep searching the archives) - we have so much nice G3 5/16" chain on this boat -- in fine shape. And now we seem to want to upgrade to an electric windlass -- and if I believe what I read, I now need to change my chain over? We have an ABI manual windlass now, and the chain works brilliantly in it............do we really need to change over?
__________________
When is the last time you tried something for the first time?
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04-08-2009, 00:33
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#32
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cruiser
Join Date: Nov 2007
Location: Probably in an anchorage or a boatyard..
Boat: Ebbtide 33' steel cutter
Posts: 5,030
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Interesting site on anchor forces here.....
Forces
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04-08-2009, 02:17
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#33
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Marine Service Provider
Join Date: Oct 2005
Posts: 1,659
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Quote:
Originally Posted by windsaloft
WOW - I *do* feel like a knowledgeable punter. This is a truly wonderful resource for excellent info. WHen I bandy my CF gained knowledge around at the chandlery, esp as a woman, they look at you REALLY sideways. It is fun. Many thanks.
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Isn't it a bit of fun when you know more than the bloke selling it
Quote:
SO -- last question all about chain (and I will keep searching the archives) - we have so much nice G3 5/16" chain on this boat -- in fine shape. And now we seem to want to upgrade to an electric windlass -- and if I believe what I read, I now need to change my chain over? We have an ABI manual windlass now, and the chain works brilliantly in it............do we really need to change over?
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No but maybe Yes. All depends on what gypsy (wildcat) you can get with the winch. Best to go winch shopping with the size of your chain in mind. Most winch manufactures make gypsies to suit most commonly available chains so everything being equal you'll just have to say "Yeap, I'll take that which but please make sure the gypsy fitted is the correct one for my existing chain".
Considerations - make sure you do know what chain you have. If not exactly sure measure it well, preferably with verniers as the Mk1 Eyeball measuring system does have errors which are often larger than the gypsie tolerances. Worse case cut a foot of the chain off and take it with you.
Also if it is a US made chain it maybe (most likely is) differing measurements than what the rest of the world usually use as their standards so if you get a EU made winch they may have to get a gypsy in for you that will suit. If you buy a winch in the US one would expect they would have gypsies to suit....... but these days....... if you catch my drift.
If you can't get a gypsy to suit your existing chain the news isn't crash hot and your wallet may have to feel a bit more pain.
And when matching gypsies to chains 'That's close enough, she'll be right' is NOT good enough unless you carry lots of winch spare parts (a gearbox and main shaft at least) and/or have a big wallet.
Now you're armed and dangerous - Go get em killer
Quote:
Originally Posted by conachair
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Some good info but remember a lot is theoretical calculations so keep that in mind. Theory and reality sometimes can be quite different.
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21-03-2010, 17:03
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#34
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Registered User
Join Date: Mar 2010
Posts: 17
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Thanks
This really is an excellent thread. Thanks to all.
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21-03-2010, 17:38
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#35
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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: 21,460
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G'Day Windsaloft,
Considering that you have "lots" of existing chain, I'd add my vote to whack off a short length (Maxwell asks for about 18") and carry it around with you while you are windlass shopping. Our chain is of unknown origin, and when we were sizing a new gypsy at the Maxwell distributer near Brisbane, he pointed out that they had 10 different gypsies for nominal 3/8"/10mm chain alone. He spent quite a long while trying our sample on different ones before selecting one for us.
Finally, I'll add my congratulations to the contributers to this thread -- thoughtful, knowledgable, and pretty free from personality!! Good job, guys...
Cheers,
Jim and Ann s/v Insatiable II lying Church Point, NSW, Oz
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21-03-2010, 19:26
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#36
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Registered User
Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 20,950
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Do read the Dashew's opinion on this subject.
I would always go for more chain, stronger chain, if feasible.
My own chain is 3/8 G-3. If I can get g-4 (= G-40) 5/16
I WILL
Your chain is there to use it. If you can get one that is stronger, longer... do!
barnie
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21-03-2010, 19:34
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#37
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Registered User
Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 20,950
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Do read the Dashew's opinion on this subject.
I would always go for more chain, stronger chain, if feasible.
My own chain is 3/8 G-3. If I can get g-4 (= G-40) 5/16
I WILL
Your chain is there to use it. If you can get one that is stronger, longer... do!
barnie
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23-03-2010, 09:45
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#38
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Registered User
Join Date: Oct 2009
Location: Annapolis
Boat: Nordhavn 47
Posts: 797
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While there are a lot of things I oversize or buy overbuilt, chain, for some reason, is one I have always felt comfortable staying within suggested size ranges. I guess it stems from my distrust of the anchors ability to hold at the breaking strength of the chain.
I am rethinking that strategy now that several of the newish anchor designs are showing more predictable holding ability at these forces. I am beginning to think that maybe the anchor is no longer the weakest link in the anchoring system afterall.
Jim
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23-03-2010, 14:02
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#39
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Registered User
Join Date: Jan 2010
Location: Punta Gorda Fl.
Boat: 1979 Hunter 37 cutter
Posts: 33
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My chain supplier is very very concerned about the metalurgy in current HT chain. He is convinced it all comes from China where they taint the milk and the drywall and poison kid's toys. He won't sell me HT chain at present. I went to WM and saw "made in America"on their ACCO chain barrels. I asked if that referred to the chain or the barrels. No one knew.
I am sticking with my 3/8 BBB for now. When I change it will be to 5/16 HT. I have a 37 Hunter cutter. spec'd at about 17,000#. 20,000# on the yard strain gauge. I rely on a CQR 44 as my primary anchor, Fort FX-37 backup.
__________________
I'm the one with the hat.
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23-03-2010, 18:57
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#40
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Registered User
Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 20,950
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all chain made in PRC
I would guess ACCO in the US, there is also at least one Italian manufacturer (Maggi?) and maybe more in the EU.
But the EU made (?) chain does not bear any stamping (?) so I would much sooner buy a G-4 for at least we know what it is supposed to do. Buying from a local (EU) bucket - how do I know the chandlery guy has not put a PRC chain into a "made in EU" bucket ???
b.
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29-03-2010, 12:11
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#41
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Registered User
Join Date: Nov 2009
Location: Dartmouth and Bristol, England
Boat: Northwind 50 - 50ft - Camille
Posts: 40
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In my view, it is principally the snatch when the catenation is eliminated (or nearly so) following wind on bowside that causes problems. May I suggest a riding sail and also holding the rode at, say, 25 degrees off. The point of the latter is to keep a constant strain on the rode and greatly reducing the possibility of swinging from one bowside to the other (which causes the snatch). Technique is important and a single focus on chain quality and size is not all. By the way, at anchor when hurricane Ivan came through my High Tensile chain ( 3/8 inch/ 10mm with a 50' 20 tonne yacht) did fine service. It did not stretch the links at all. That's where I learned the hard lesson about snatch - watching it happen. How the roller and cleat held I do not know!
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01-05-2010, 22:26
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#42
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Registered User
Join Date: Jun 2009
Location: In transit ( Texas to wherever the wind blows us)
Boat: Pacific Seacraft a Crealock 34
Posts: 4,115
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Just found this thread, don't know how I missed it.
In my reading and research I found hints to the stretch of BBB (PC does too?) but never quiet an outright discussion of the merits of something stretching before giving way. That pre failure indicator really appeals to me more than breaking strength figures.
So am I trying to figure out what would be a good ground tackle for my boat, a 30 ft low freeboard full keel 6 ton sailboat, and I thought I had it all figured out until I read this thread, now I need to process the new info. But to clarify a bit (sorry you have to repeat yourself, my brain is mush with this anchor tackle stuff)
Basic strength between G3 and G4 are roughly the same? one stretches then breaks and the other is a bit more "brittle" and will fail without warning?
Gmac, would you allow me to anchor up wind of you with 200 ft 1/4 BBB?
Erika
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03-11-2010, 13:58
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#43
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Marine Service Provider
Join Date: Oct 2009
Location: In the U.S.
Boat: FP Tobago 35 [sold]
Posts: 426
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HT vs EN 818-3 chain
Curious if anyone might comment on this.
Specs for HT 5/16 (Acco) (G40) chain is SWL 3900# and Break at 11600#. So, as we have a ratio of 3:1, which is what others have posted and is in line with the US "bumping" their numbers a bit.
We take a Maggi 8mm EN818 chain, also G40 based on this thread (or whatever letter it is now ), it has a SWL of 2200# and a break, assuming they use a 4:1 ratio, of 8800#.
Ok, now, 5/16" = 7.94mm, almost 8mm, but not quite.
So, if dumb 'ol me was looking at the basics, I would have to guess based on ratios and chain size, the EN818 Maggi chain should have a tiny-tiny higher break load since its .06mm larger. No?
Well, no, not from all these #'s. So, what am I still missing. How can 2 "G40" chain's, basically the same size, have a 2800# difference in breaking load....... (I hate marketing!)
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03-11-2010, 19:21
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#44
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Marine Service Provider
Join Date: Jun 2005
Location: New Zealand
Posts: 407
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The Maggi figures for their EN 8 mm chain (G40) happen to be identical (in terms of break) to their 8 mm DIN G30. If you look at this C-link testing here, 8 mm G40 is tested to a break of 4,900 kgf. That's still less than the ACCO figure you mentioned (which you will find notoriously difficult to find from Peerless these days - they want you to use the WLL # and not worry about anything else).
There is also a difference between the "standards" break load and the actual Maggi figure - if you look at their catalog, there is "Norme BLL" vs "Maggi BLL". The Maggi figures usually exceed the standard, although in the case of 8 mm EN-818, the 4030 kgf figure is the same for both. In any case my suggestion is that Maggi's figures are conservative.
The other factor is that the ACCO chain tends to be a 430 grade, not actually 400. Together, that explains the discrepancy.
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03-11-2010, 19:32
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#45
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Marine Service Provider
Join Date: Jun 2005
Location: New Zealand
Posts: 407
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Quote:
Originally Posted by Ocean Girl
In my reading and research I found hints to the stretch of BBB (PC does too?) but never quiet an outright discussion of the merits of something stretching before giving way. That pre failure indicator really appeals to me more than breaking strength figures.
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I don't know why you would like the idea of your chain stretching. Once it's stretched, the steel has passed yield, and it's stuffed. As in destroyed. Buy new chain. Weaker chains stretch earlier than higher tensile versions because their yield points are a lot lower. Do you really imagine, in the conditions you might conceivably bust chain, that you will be watching the links with a gauge - "ah she's starting to stretch now, she'll break soon!"
No. Keep it simple. You need a certain strength and thereafter most boaters want to keep weight to a minimum. Strong chain means light chain, which is good.
Quote:
Originally Posted by Ocean Girl
So am I trying to figure out what would be a good ground tackle for my boat, a 30 ft low freeboard full keel 6 ton sailboat, and I thought I had it all figured out until I read this thread, now I need to process the new info. But to clarify a bit (sorry you have to repeat yourself, my brain is mush with this anchor tackle stuff)
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You should match the chain to the anchor, it is the anchor that holds your boat. The rode connects the two together, and there's little point in having rode that's way stronger than an undersized inadequate anchor would require; conversely if you have a high performing over sized anchor, you don't want the rode to be unmatched.
If you are asking re the anchor too, then let's imagine a Rocna 10 (22 lb) on your boat, in which case 8 mm or 1/4" G40 (high test) would be appropriate.
Quote:
Originally Posted by Ocean Girl
Basic strength between G3 and G4 are roughly the same? one stretches then breaks and the other is a bit more "brittle" and will fail without warning?
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Of course not, G4 is approximately 33% stronger than G3 as the grade numbers would imply. Forget the "brittle" aspect, G4 chains are not brittle anyway - the steel in proper high tensile G7s have yields and break points that are closer together, but they're so much stronger that the G4 has long since failed while the G7 is within limits... and as above the notion that stretch is a desirable indicator of imminent failure is really ridiculous. If you're stretching chain it ain't strong enough.
Have a read over this:
Chain (Rocna Knowledge Base)
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