Kedge anchors

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mikeG

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Ok ...I'm at it again picking your brains and gleaning knowlege from your wealth of experience..right brown-nosing over .. What should I expect to pay for a "decent" Danforth style kedge anchor. Surveyor recommended I got a 9kg to supplement the 17kg 'Delta' main anchor. Seen them all prices from £25 t0 £200... can the cheaper products be trusted? If so can you recommend which. Read some horror story somewhere of fake 'Hong Kongish' anchors snapping so ...can anyone advise? /forums/images/graemlins/confused.gif
 
Get yourself an aluminum Fortress. Lightweight so easy to handle in the dinghy. Straight line holding power about the best in the business. What more do you want? Cheap price, alas no.
 
Average the LOA & LWL = about 10m for your Bav 34. The RYA Boat Safety Handbook (which more peeps should get hold of ) quotes DOT requirements for that size as 13kg Main and 6kg Kedge if conventional digging anchors. Chain/rope should be appropriate diameters: 8/12 mm for Bower, 6/10 mm for Kedge.
So your surveyor was somewhat OTT. Start from there and buy the best (nothing wrong with second-hand) taking note of reviews in yachting mags. And find a corner for a Fisherman's as your spare.
 
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And find a corner for a Fisherman's as your spare.

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Very good advise.. but the best corner for your fisherman is on your backyard... not on your boat... /forums/images/graemlins/laugh.gif
 
"And find a corner for a Fisherman's as your spare."

Do people actually use those things for weedy and rocky bottoms?

How reliable are they for, say, a 180 degree change of pull direction?
 
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Chain/rope should be appropriate diameters: 8/12 mm for Bower, 6/10 mm for Kedge.


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A typo I would suggest should be 8mm chain and 14mm rope to have a good match.

10mm rope anchoring a 34fter??? please don't use this if anchored by me, use the 14mm.

I have and love my Fishermans, it's great for hanging the wet gear on in the backyard when I get home /forums/images/graemlins/grin.gif
 
I have been trawling the internet trying to find a table that gives anchor sizes for a kedge, but nothing really helpful. It seems though that there is a rule of thumb of 1lb for each foot of LOA. This seems to check out with other ratios being quoted of kedge being about 55-60% of the weight of the main anchor.

Any thoughts?
 
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Do people actually use those things for weedy and rocky bottoms?

[/ QUOTE ]You cannot afford to do without them in some places - no other anchor is capable of cutting through kelp that's 10m long. We've spent 40 minutes getting the stuff off the anchor, really heavy, with strands as long as the boat.

We became complacent with a 35lb CQR and 35m of 8mm - and left our fisherman's in the lockup one year - until the silent 200m drag in a gale (fortunately in daylight). Never again.

Since then, we've never dragged though many others have in our presence - we were one of four that stayed in place when about twenty others dragged in a gale. We've had change of pull direction, but nothing like 180 degrees, so cannot comment on that aspect.
 
Er, s'cuse me, typos do happen but NOT a quote from a table of recommended anchor/chain/warp sizes that is readily available (tho you might have to join the RYA).

As for those Fisherman's anchors leaning against the wall, they're not only for serious cruising Ken - ask anyone in the Channel Islands. My current boat came from SPP and the ground tackle comprised two of the things plus an awful lot of string. Presumably the owner had a CQR in the garage . . .
 
Errrmm, what did I say?

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Er, s'cuse me, typos do happen but NOT a quote from a table of recommended anchor/chain/warp sizes that is readily available (tho you might have to join the RYA).

[/ QUOTE ]Not sure what you're getting at, could you explain please?
 
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I have been trawling the internet trying to find a table that gives anchor sizes for a kedge, but nothing really helpful. It seems though that there is a rule of thumb of 1lb for each foot of LOA. This seems to check out with other ratios being quoted of kedge being about 55-60% of the weight of the main anchor.

Any thoughts?

[/ QUOTE ]You won't find anything conclusive, because it doesn't exist. Most of the "tables" and "sizing charts" out there are nonsense; unit of weight per unit of LOA formulae are too simple and at best serve only as a very rough guide.

It is difficult enough to size a primary anchor. Manufacturers' recommended sizes are usually a bit optimistic, and you can't trust general sizing charts because the weight depends on the type of anchor. Fluke area is more important than weight in the context of matching an anchor to a boat.

Different boats and different people have different ideas of what a kedge is, so there's no rule as to how much smaller than your bower it should be. Just use common sense and think about what kind of scenario you're going to expect to be using it in. If you expect it to really be a double to the bower, then it should be the same. If you want a light-weight thing that you can throw around and only expect it to hold the stern steady now and again, then it can be much smaller.

If the kedge is a different type to the bower then any ratios etc become completely irrelevent in any case.
 
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You cannot afford to do without them in some places - no other anchor is capable of cutting through kelp that's 10m long. We've spent 40 minutes getting the stuff off the anchor, really heavy, with strands as long as the boat.

We became complacent with a 35lb CQR and 35m of 8mm - and left our fisherman's in the lockup one year - until the silent 200m drag in a gale (fortunately in daylight). Never again.

[/ QUOTE ]How are you sure that "no other anchor is capable of cutting through kelp"? Have you tried every single other type in the world?

Your post suggests that the only alternative you've tried is a CQR, which means you are talking about two anchor types one of which is nearly 80 years old and the other dates back too far to count. Perhaps you should try something a little more up-to-date?
 
Re: Errrmm, what did I say?

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Er, s'cuse me, typos do happen but NOT a quote from a table of recommended anchor/chain/warp sizes that is readily available (tho you might have to join the RYA).

[/ QUOTE ]Not sure what you're getting at, could you explain please?

[/ QUOTE ]

That was directed at my comment regarding the mis-match you have with 12mm rope onto 8mm chain.

Yes I do know it is in the list but I also know 8 to 14mm is a better match in real life. Using 12mm rope perfectly fine but why waste time, money and carry the weight of 8mm on it. Use 7mm and it makes a lot more sense, better balanced and matching loads.

Just beceause it's on a list does not make it right or the best option.

Like the 10mm also listed. How many out there would be happy hanging off 10mm line in a 34ft Bav? Not many I would suspect.

RYA do a good job in places but also have some very strange ideas. No lead in monkeys fists as it may hurt if it hits someone, that is fine. We are allowed to use golf balls though as they don't hurt if they hit you in the head.... Yeah right!!
 
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Have you tried every single other type in the world?

[/ QUOTE ]No, and I wouldn't buy one from a smart Alec either. So that's Rocna off the list.
 
Mmmm... some interesting comments ...loved the spat with the Kiwi anchor maker! Did I read about your anchor drag in the mag recently Sgeir? I have actually been on the Rocna website and they do look pretty impressive together with testimonials etc.( Am trying to contact one guy who uses his off the Outer Hebrides.... Pretty expensive to ship over I expect. If I went for an aluminium Fortresss would I be able to drop down to the 6kg size?
 
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...loved the spat with the Kiwi anchor maker!

[/ QUOTE ] /forums/images/graemlins/cool.gif Quite funny considering the guy's been breaking the forum rules for yonks (free commercial advertising in his signature, profile, and posts, without any corresponding YBW link).

I'm sure the Rocna is actually very good and the tests in sand were impressive (though personally I'd never lay a plough or CQR by dropping it on its side - most people would be going astern first). However my post was specifically about rock and kelp. I notice that when hes asked 'How are you sure that "no other anchor is capable of cutting through kelp"?', he ommitted the last three words of my sentence 'that's 10m long'. That does make me wonder a bit.

I'm sure people use them in the Hebrides and get excellent results in the places where we all prefer to anchor ie sandy or muddy bottoms. But I'd be interested to hear whether they hold in gale conditions in places like Craighouse that are known for serious problems with weed.

On the west coast, we often come across the long kind (don't know the proper name) that has a round stalk over one inch thick, that's 10m or greater in length, and grows in immensely dense patches. Frankly I suspect that a relatively light Rocna kedge (or even heavier main) would have similar problems to a CQR or plough design in thick kelp - the kelp would bunch up in the space between the plough blade and the shank, and the blade would probably never even touch the bottom. IMHO, but I'd be happily proven wrong in any proper tests.

On the issue of the Fortress, probably an excellent kedge in sand or mud. However, its properties are probably similar to your main anchor - good in sand and mud, no use in rock or kelp. FWIW in rock/kelp situations, I would consciously use the heavy fisherman's as a kedge, rather than our other "other" anchor, a 25lb Plough, simply because it has quite different qualities, and is superior in those specific conditions (but not in sand).

My instinct would be to feel very uncomfortable with only a 6kg Fortress kedge in a 34' Bav, but have no experience of them. If you feel Fortress is right for you, might be better going up the scale a wee bit.

Must have missed the article - which mag, when?
 
I used a 6 kg Fortress as a kedge on my 34-foot Koopmans (weight appr 6 tonnes) and had good results. In the cases it did not hold I felt it was due to the bottom and not to the anchor. I just bought a Wharram Tanenui (length 8,60 meters, weight appr. 1200 kg) and consider a 3,5 kg Fortress as a kedge.
 
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