Anchor type?

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We anchor in some pretty trying conditions around here and never have any problems with jerking, etc so no need for any ropey stuff - and then some anchor manufacturer comes up and says that his anchor is not guaranteed cos it might bend if I don't use 10 m of the ropey stuff as a snubber.



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I do not think you understand my point John!..

With the "old generation" anchors, during peaks of load, the anchor was dragging or breaking free..

With the "new generation" ones, which have a much higher holding, under high loads, they will not break free, but either the
fluke, the shank, the rode or even the cleat on the deck can break, and this is why you must use any kind of snubber in your anchoring line..

Deltabent.jpg
 
/forums/images/graemlins/frown.gif Err, our anchor has never broken free, dragged and certainly has never bent.

I suspect that your anchors are weak in the stock in order to preserve balance but that is a structural design inadequacy for which your "fix" seems to be to minimise loads on it /forums/images/graemlins/crazy.gif

John
 
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Way down south here we have lots of Spades and Rocnas on boats.

Stop pulling their legs GMac. They are actually as rare as hens teeth, Rocna's especially. In fact probably rarer /forums/images/graemlins/smile.gif.

John

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When you come north next time take a walk around Westhaven, Bayswater (6 boats in a row there this morning on F pier alone, near the start, you can't miss them) or West Park, you will see a lot, not one or 2, a lot.

I know of 4 Rocnas being used on a daily basis in Nelson along side 12 Spades (4 are Alloys as well). Why? They could not get any other anchors to work. They are all being used in a very extreme situation that is above what an average boat would do. Frankly I'm surprised anything works actually, the guys are raving nutters :-). Swapped out 10kg Deltas for 4.5kg Alloy Spades and are very very happy. Take a taxi and have a look. I'd wear a bloody good lifejacket and kevlar undies though, it is quite scary :-)

Don't forget every 100 miles we travel south we set our clocks back 10 years :-), the reverse applies to you :-) and you're not exactly in the countries boating mecca, so to speak :-)

This is what was retrieved on the 2nd deployment. They did not even feel it go so becareful when commenting on other people strengths. Was oversized to the boat with a very experiance crew. 25kg by the way on a 11mt inflatable.

P1010021_sml.jpg
 
4 Rocnas being used on a daily basis in Nelson

Which must make them about the rarest anchor in Nelson /forums/images/graemlins/smile.gif. There are close to 500 boats in Nelson marina alone, so much less than 1% have Rocnas?

You may like to tell us how many boats there are with other anchor types in Westhaven, Bayswater, etc? I think that you will come up with a somewhat similar result.

No need to comment on the tinfoil anchor - the photo says it all.

As I spend half my life very much closer to the equator than Auckland is, I thank you for the compliment that those of further north have the most modern practices /forums/images/graemlins/smile.gif.

John
 
OK point taken - but its still my belief that Bruce yacht anchors hold well when the vessel is stationary, not expected to swing and certainly suspect when wind and/or tide cause the anchor to change position and reset.

Experience I have with them suggests that they are not designed for this, hence my comment.

Donald
 
most tests have them (bruce) setting and resseting very well (excluding weed) - what they don't have is holding power (on a relative p/w basis)

as both the pictures above show some anchors experience huge forces (although the top one does look as if it was wedged in rocks and possibly damaged in recovery).
 
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OK point taken - but its still my belief that Bruce yacht anchors hold well when the vessel is stationary, not expected to swing and certainly suspect when wind and/or tide cause the anchor to change position and reset.

Experience I have with them suggests that they are not designed for this, hence my comment.

[/ QUOTE ]Donald I'm not quite sure what you're saying as you state that your experience with them suggests they're not designed for something that is otherwise your belief?
/forums/images/graemlins/confused.gif

Anyway perhaps your belief is not consistant with the results of the old (1995) anchor study by US Sailing, which involved three sets of results from straight-line testing and conclusively proves that Bruces do not develop good holding power, even in the context of the traditional anchor types: http://www.ussailing.org/safety/Anchor/anchor_study.htm

For those that can't be bothered reading the whole thing, here is a summary of the results compared to two other tests. (Nb. this is only testing straight line pull, so is not an overall performance index as there are other important factors)

pull_tests_ussailing_table.gif

Look at the URL above for details.

Our own testing (so disclaimer: not independent) confirms these results. We also tested setting performance and heavily penalized failure to set: http://www.rocna.com/main.php?section=real&chapter=testing&page=0

Champions of Bruce and claw-types like to claim that they set and re-set well (and lack of holding power can be compensated for by over-sizing) but again this is not true. It can set quickly, and usually does, but the problem with it is you can't be sure. Particularly on hard sand it is quite capable of lying on its back and skating along quite happily:

testing_claw_dragging.jpg


<span style="color:brown">"... much of their popularity derives from the ease with which they stow on the stemhead. But their performance proved disappointing... the Bruce anchor's reputation was founded on it being used to anchor oilrigs but a Bruce of dozens of tons is a very different animal from the ones we tested. In gravel these claws bounce about whereas in sand they lie down on their side and rarely exceed 200Kg of holding power."
– Antoine Sézérat, Voiles et Voiliers, translated from the French.</span>
 
Now Craig you were doing very well until you bought up that test again......... /forums/images/graemlins/laugh.gif

Here's another that supports the 'poor overall holding power but OK setting resetting' view.............. anchor test results

sorry but your test really didn't do you any favours IMO.

btw - saw my first ROCNA anchor on a boat in Poole Harbour last weekend. Looked a serious anchor on a serious cruising boat!
 
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Now Craig you were doing very well until you bought up that test again......... /forums/images/graemlins/laugh.gif

Here's another that supports the 'poor overall holding power but OK setting resetting' view.............. anchor test results

[/ QUOTE ]This is the same Practical Sailor that recently concluded that some anchors work better in soft mud using 3:1 scope instead of 7:1?
/forums/images/graemlins/crazy.gif

Seriously, magazines rarely get any kind of good assessment of setting performance; even the good articles (and the Jan 01 one you linked to isn't bad, it's before Practical Sailor's testing went to the dogs) don't do enough trials in enough variations of bottom types. The conclusions are usually worthless. Again, I'm not claiming "the Bruce never sets" - I'm saying it usually does, but is too inconsistent to be reliable (compared to modern designs). Add that to the fact that it's holding power is shocking, and it astounds me that people still subscribe to the Bruce marketing line after all these years. As GMac said, McDonalds wins.

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btw - saw my first ROCNA anchor on a boat in Poole Harbour last weekend. Looked a serious anchor on a serious cruising boat!

[/ QUOTE ]Excellent, what size was it?
Did you talk to the owner?

Good to see a few making an appearance over there then.
 
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With the "old generation" anchors, during peaks of load, the anchor was dragging or breaking free..

[/ QUOTE ]I'm finding that hard to believe. 'Old' anchors have been holding vessels perfectly well in severe storms without bending, breaking or breaking free, for decades. As for using a snubber, one of the key reasons I use a snubber is to stop the jiggling load wearing the gypsy, and the noise.

When the wind gets up I shackle a couple of lines to the chain rode and lead them back to deck cleats to spread the load and avoid putting the stress on the windlass.
 
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4 Rocnas being used on a daily basis in Nelson

Which must make them about the rarest anchor in Nelson /forums/images/graemlins/smile.gif. There are close to 500 boats in Nelson marina alone, so much less than 1% have Rocnas?

500 boats used each day in Nelson, so that's why the bloody South Island has to be proped up by us up North. /forums/images/graemlins/grin.gif 16 boats and anchors being used by 2 companies. 25% of them are Rocnas, is what I actully was referring to.

Only 1 Mercedes-Benz SLR McLaren in NZ amongst 1,000,000 odd other cars. Obviously no body wants one of them either /forums/images/graemlins/grin.gif

You may like to tell us how many boats there are with other anchor types in Westhaven, Bayswater, etc? I think that you will coe up with a somewhat similar result.

Strange you should ask that now. We got a letter saying Sarca has 1/3 of the market about a week later one the same but said Delta had a 1/3. Obviously complete c**p so we actually counted every anchor in Westhaven and Bayswater. The numbers are at work, I'll get back to you. The most common by a very long long way was Manson Ploughs but the rest was quite interesting. Oh yeah 2100 boats odd and we only found 1 Sarca.

I know on F pier (been on that a lot in the last week or so) the number of Spades and Rocnas is around 16-18%.

No need to comment on the tinfoil anchor - the photo says it all. Doesn't it /forums/images/graemlins/grin.gif

As I spend half my life very much closer to the equator than Auckland is, I thank you for the compliment that those of further north have the most modern practices /forums/images/graemlins/smile.gif.

That why you southern lot keep pinching our rugby players ?? /forums/images/graemlins/grin.gif/forums/images/graemlins/grin.gif/forums/images/graemlins/grin.gif Auckland ... blaa... what a dive of a spot, who would want to live there? Glad I don't /forums/images/graemlins/grin.gif/forums/images/graemlins/grin.gif/forums/images/graemlins/grin.gif
 
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