Advice about my anchor and chain please - see photos

[[70521]]

You - and I - don't need all-chain. The actual mechanics of what goes on tells us - eventually, when we're willing to listen and think - that a length of chain next to the anchor followed by a good rope warp is optimal.... and especially so when you're hand-hauling the lot up. Yes, it works fine.

So I'd recommend you aim at having a chain-rope setup. You'll thank me for it - mine's a pint - and keep your 'redundant' length of chain for use with a SECOND anchor. And warp. That's just good seamanship.

I'd be interested to hear your reasoning behind those statements.

 

[Neeves]

My tuppence worth - I've got a Kobra and it's been great, it's the folding one, which I'm in the process of getting welding in a permanently open position as the bar that it folds over has come away from the stock.
I've also just replaced our 30mtrs of chain, which was 8mm with 6mm, as it was a lot worse than yours. I was working on Vyv's advice, the percentage corrosion.

I too found my Kobra good value, it sets well and quickly and develop sufficient hold (assuming you follow the size of yacht vs anchor size spreadsheets) and also had it welded up. I could see no benefit to the folding mechanism (at all). Ideally one would re-galvanise - I painted with a zinc based paint which works well as the welding is in the underside of the fluke that enjoys no, or minimal, wear.

Jonathan

 

[Neeves]

I'd be interested to hear your reasoning behind those statements.

I too will be interested in Zoidberg's comments.

In the interim, another of my links

http://www.mysailing.com.au/cruising/the-art-of-snubbing-in-the-nicest-possible-way

I think there are some interesting graphs in the article comparing length of nylon with length of chain and the ability of each to 'absorb' energy. A mixed rode is simply a short chain rode with a permanent snubber. If your cruising ground offers no, or little risk of abrasion the question I would ask of you is very simple

Precisely why do you, or many people, carry an all chain rode?

Textile is cheaper and lighter.

And if there i one thing most owners agree on is that - chain costs money!

Admittedly here in Australia most yachts, or owners, have ambition to escape to the balmy north and escape the hard winters for which the southern part of the island suffers . Coral eats nylon as an overnight snack - so most yachts are kitted out with an all chain rode.

Jonathan

 

[noelex]

Hi Douglas

The west coast of Scotland has some wonderful anchorages so getting your anchor gear in better shape makes sense.

Firstly, could you take a close look at your anchor in the area I have circled in blue. Unfortunately, the photo does not have enough resolution but there is a suggestion of a crack forming in the weld between the fluke and the shank. This could just be a crack in the zinc coating or an artefact of the photo. A careful visual inspection should be enough to tell but this should be done before using the anchor. While you are inspecting the anchor also check and see how much wear there is in the pivot pin. Anchors with moving parts like this CQR copy do deteriorate. Saltwater and abrasive sand is tough environment for moving steel parts and wear on the pivot pin effects the anchors setting geometry.

If you are purchasing a new anchor, the Kobra 2 would be a reasonable choice. It is excellent value for money. There are better anchors though. The Mantus, Rocna and steel Spade are all a significant improvement over the Kobra, but at a much higher price.

As has been indicated, the shackles definitely need to be replaced, as do the very rusty bits of chain. I presume you do not have a windlass, in which case the remaining good lengths of chain can be joined with a simple shackle. This will not pass through a windlass gypsy, but if you are retrieving the chain by hand, shackles are cheap and easy. They are better than the suspect “C” links you currently have (good quality “C” links are fine, but many are poor quality) so replace these with shackles as well. Join together the good bits of chain and see how much you have. You will need some rope rode as well anyway so the loss of some chain length should not be a great problem.

Lastly, it's well worth the time reading this enourmous thread on CF - it has tons of pictures of various anchors and excellent advice on how to use one properly: http://www.cruisersforum.com/forums/f118/photos-of-anchors-setting-126073.html

Thanks Yngmar.
Douglas, there are many photos there of the Kobra in action underwater, together with the other designs I have mentioned. The difference in performance is quite obvious. Looking at the photos you should be able to make up your own mind if the extra cost of the very best anchor models is justified.

 

[[70521]]

http://www.mysailing.com.au/cruising/the-art-of-snubbing-in-the-nicest-possible-way

Thanks Jonathan some interesting thoughts.

I've always snubbed but only to bow cleats. Never thought of running a long snubber back to the transom as I am heading past 60°N in a couple of years will give that some thought.

 

[Neeves]

Sandy,

You are welcome.

I would not have believed it but development of snubber use is an ongoing technology and there are further options (being trialled). Keep in touch here, YBW, and I am sure whatever transpires will be reported

- and however it develops....

- it will be cheap

In the mean time - think of running your snubber from the transom and running outboard before you get to the bow (this is the difficult part, but not impossible, and tends to be yacht specific) - and then run another snubber down the other side, both snubbers to a common chain hook. You then have a bridle - which will reduce yawing (and I believe yawing is a major contributory factor to an anchor dragging). One of the trial yachts (not a multihull) is on its way, north, to Alaska currently. There will be an article in SAIL about this 'soonish' - I'll post a link when available.

Jonathan

 

[Crinan12]

Continuing thanks to all

Noel I don't think it's a crack. I had another look. I did just discover another anchor which was hidden away!It's a 15kg cqr. I presume I might as well attach this one when I replace the shackles as it's heavier.

I don't have a windlass

I've taken some more photos to give a better idea of the condition of the chain. The trouble is I don't really know what constitutes bad. To me a lot looks okay and then there are sections where there are half a dozen or so links which are much rustier than others. These are often at points where there are bits of old string where the chain has been marked. I don't know if that's just a coincidence.

Thanks for providing the links. It's given me plenty reading material and I can decide what to buy if anything over the winter. I still have to learn to sail!

 

[Neeves]

This article, link already provided earlier, has detail on anchor lockers

https://www.sailmagazine.com/diy/know-how-ground-tackle

Leaving dirty (mud) wet chain in an anchor locker and/or chain sitting in close proximity to wet rope (or wet string/ribbons as chain markers) is a sure way to engender accelerated corrosion.

Jonathan

 

[Trop Cher]

As you plan to anchor frequently, why don't you just buy some new chain, then you know exactly what you've got, especially if you buy certified chain. There's many things you can save money on but chain, anchors and shackles shouldn't be on that list! Compared to many boat related purchases, chain isn't that expensive, also think of the savings you will make in the long term not paying for visitor moorings!

 

[steve yates]

I'd be interested to hear your reasoning behind those statements.

I would have thought all chain is required for anchoring in coral, but perhaps not a requirement for elsewhere?

I would also have thoguht, but don't know, that anchor rode would give a greater snubbing effect than all chain. Regardless, it's not going to snap! Unless it is cut by running over a sharp surface, like coral. I doubt tats an issue in scotland. Even rocks, of which we have a great deal, are probably not the big issue in anchoring spots, as if its a rocky seabed iots unlikely to be a good anchoring ground anyway.

 

[Quandary]

As you plan to anchor frequently, why don't you just buy some new chain, then you know exactly what you've got, especially if you buy certified chain. There's many things you can save money on but chain, anchors and shackles shouldn't be on that list! Compared to many boat related purchases, chain isn't that expensive, also think of the savings you will make in the long term not paying for visitor moorings!

Not to mention the hours of uninterrupted sleep.

 

[Stemar]

Hi Steve, why would the same anchor perform differently for you do you think?Thanks

It may have been a smaller one (the recommended size, rather than the oversized one that was there when I bought the boat), but I'm not sure they were different. It's funny, faced with a row of anchors, I had no idea which was the the size I'd had before. Other possibilities could be wear blunting the tip or wear on the swivel that let the head lay too flat, but TBH, I don't really know. What I do know is that, had I not had the first one that set fine, I'd be firmly in the CQRs are useless camp, as seen here.

 

[Crinan12]

Hi stemar/Marc/anyone else
6mm chain had been suggested - I went to order this via Jimmy green but noticed they recommend it up to 6m boats only. I emailed them and they said they would not recommend 6mm chain for a 4 tonne boat
I would much prefer to have 6mm chain as it's significantly cheaper and lighter- can anyone reassure me that it will be fine?
I know it's not an exact science
Thanks

 

[vyv_cox]

Hi stemar/Marc/anyone else
6mm chain had been suggested - I went to order this via Jimmy green but noticed they recommend it up to 6m boats only. I emailed them and they said they would not recommend 6mm chain for a 4 tonne boat
I would much prefer to have 6mm chain as it's significantly cheaper and lighter- can anyone reassure me that it will be fine?
I know it's not an exact science
Thanks

A reliable rule of thumb is provided by the Prof. John Knox expression Force (in kg force) = (1/500) x (LOA in metres squared) x (wind speed in knots squared)

In a good hurricane of 60 knots this gives us 1/500 x 9 x 9 x 60 x 60 = 583 kgf.
In a possibly more realistic wind strength of 40 knots we get 259 kgf.

The SWL of 6 mm chain is 400 kg. However, even at 583 kgf you would be below the yield strength which I would estimate to be around 60% of the UTS of 1.6 tons, = 960 kg. It is debatable whether your anchor or deck cleats would resist loading of this sort of level.

I reckon well-made 6 mm chain should be perfectly adequate under realistic conditions..

 

[scottie]

Hi stemar/Marc/anyone else
6mm chain had been suggested - I went to order this via Jimmy green but noticed they recommend it up to 6m boats only. I emailed them and they said they would not recommend 6mm chain for a 4 tonne boat
I would much prefer to have 6mm chain as it's significantly cheaper and lighter- can anyone reassure me that it will be fine?
I know it's not an exact science
Thanks

Perhaps not an exact science but there is a lot of experience at Greens which I suspect you might ignore at your peril

 

[Quandary]

Perhaps not an exact science but there is a lot of experience at Greens which I suspect you might ignore at your peril

Perhaps, but given a choice between taking reasoned advice from Vyv versus the sales assistant in Jimmy Greens I know who I would heed.

 

[Crinan12]

Thanks for the example vyv very useful
I'm going to go with 6mm chain I think
Presumably there will be a lot of boats out there with g30 8mm chain, which would not be superior to g40 6mm chain anyway
Cheers again

 

[vyv_cox]

Thanks for the example vyv very useful
I'm going to go with 6mm chain I think
Presumably there will be a lot of boats out there with g30 8mm chain, which would not be superior to g40 6mm chain anyway
Cheers again

My numbers are based on grade 30 chain, didn't realise you would be buying grade 40, so an unexpected bonus. SWL of 6mm grade 40 is 675 kg

 

[vyv_cox]

Perhaps not an exact science but there is a lot of experience at Greens which I suspect you might ignore at your peril

Ironic tale about that. A couple of years ago one of my contacts discussed with Jimmy Green my recommendation of three chain links between a Kong swivel and the anchor shackle. He was told it was totally unnecessary and they would not advise it. Now they will sell you three links of chain specifically for that purpose.

 

[Crinan12]

That's even better vyv
6mm sounds like the best option for me
Jimmy green don't actually sell any grade 30 chain - grade 40 is the minimum
Cheers