Anchors (again)

[Yealm]

Fresh back from lunch at Polhawn Cove, I'm keen to embrace anchoring.
I've worked out my little anchor locker will just fit a Rocna 10kg, 15m chain and 30m rope (Contessa32).

What would this realistically allow me to do ?
Is it enough for benign-ish Summer conditions (sheltered anchorage South/Southwest coast (excluding Scillies) overnight, sand or mud, absolutely max of a F4)?
And if so, how much rope should I put out (assuming water depth range 5-10m)?

Grateful for any advice

 

[Tranona]

I will stick my head above the parapet!

Absolutely fine. I use a 10kgs Delta (but all chain) on a slightly bigger and heavier boat in the same situations. Never had a problem. Let out as much rode as you think fit. Does not matter that part of it is rope. Your set up if you dig the anchor in properly will cope with far more than what you have stipulated including going to the Scillies.

Folks have been anchoring all round our coasts perfectly safely with far less effective setups than what you are proposing!

 

[LittleSister]

I think it will be fine for far more challenging conditions than you are proposing.

Rocna says 'We base our calculations on 50 knots of wind, associated surge, and poor holding bottoms.' Very few leisure sailors will ever find themselves in such a coincidence of all three bad conditions at once. Eliminate any one of them, and your anchor should be fine for a boat significantly bigger than yours.

Your (notional) displacement is only slightly above the size recommended by Rocna for that combination of adverse conditions. The next size up Rocna is 50% heavier, and substantially bigger (and won't fit in your anchor locker!), and is recommended for vessels of your length but twice the displacement!

Or to look at it another way, by all objective measurements and tests your 10kg Rocna should be significantly more capable than the CQRs, Bruces, Danforths etc. that fitted in Co32 anchor lockers, and with which people have been successfully setting out to sea in Co32s for decades without giving a second thought.

(n.b. I am not knocking 'old generation' anchors (I've only ever had old-gen anchors myself) - they have proved themselves adequate. New generation anchors should be even better.)

 

[Stemar]

Wow, that's three people on an anchor thread that agree with the OP's ideas

The only thing I'd consider is more rope. 45m of rode is 15m depth at a scope of 3:1, actually more like 14 because your bow roller is above the waterline. I'm entirely with you about not anchoring in more than F4, but there are times it doesn't work out that way - I've found myself anchored in F7, and more scope is what you want then. More rode also allows you to drop the hook in deeper water. You may never need it, but it does give you more flexibility, and rope weighs next to nothing, so it won't load the boat or your back when you're pulling it in.

Cue those who are convinced you'll die if you don't have at least 100m of all chain...

 

[Yealm]

Yes I wasn't sure if my chain scope of 1.5 to 1 at high tide was sufficient, but that's given me greater confidence

 

[awol]

All fine except the Rocna. Helping "Britain Build Back Better" by choosing a Knox would be more patriotic!

 

[Boathook]

Sounds fine but as others a bit more rope. Chain / rope rode is normally at 5 times the depth and 3 times for all chain as a rough guide. I've got a 16kg rocna and it digs in well and I suspect that for a lunchtime stop I could get away with 2 times depth with all chain. Don't forget that depth is from the bow roller to seabed. Possibly doesn't make to much difference in deep water but in shallow water ....
I would look at the knox if I was buying an anchor now, but it had only just come onto the market when I got the rocna so a bit of an unknown at the time.

 

[andsarkit]

All fine except the Rocna. Helping "Britain Build Back Better" by choosing a Knox would be more patriotic!

I aquired a 9Kg Knox from a Contessa 32 owner who was selling it because it would not fit in the anchor locker. Although I have a smaller boat I don't have an anchor locker and so it sits on deck in place of the CQR. I'm very happy with the Knox as it seems to set instantly.

 

[James_Calvert]

When I needed more rope than I had on my chain/rope rode, I added a mooring line to it.

 

[awol]

My Knox fits perfectly on my CO32 roller. Mind you, Prof. Knox made a specially modified roll bar to clear the pulpit centre support. Why not ask Geoff if he is offering the same change?

 

[arto]

I used a 10Kg Delta and (I think) 60m chain when I had a CO32, but that was partly because of the surveyor warning me that Wales and the Bristol Channel was an area that required particularly robust ground tackle. It was my first boat and I was cautious, and back then, the Delta was the bees knees. Only dragged once and that was harmlessly somewhere in a deep part of Fishguard harbour. Still not sure whether it was lack of scope or poor holding. Otherwise all was well, including Scillies and some bits of Scotland.

The only point I'd question would be your (laudable) aim to never anchor in more than F4. It's fine as an ambition but unless you've managed to grab the controls of the weather machine, you're going to find yourself anchored in > F4 almost regardless of intentions. It might be F4 when you drop the hook and the forecast may be delightful, but you can be sure that one night you'll be woken by the wind whistling through the rigging.

 

[CAPTAIN FANTASTIC]

The answer to your question; how much rope to put out in 5m and 10m of water. I use: 25m plus 2 x depth. Therefore in 5m depth: 25 + (2x5) = 35m of chain/ rope combination and for 10m depth it would be 45m. If I am expecting bad weather , I add 10m.

 

[Yealm]

The answer to your question; how much rope to put out in 5m and 10m of water. I use: 25m plus 2 x depth. Therefore in 5m depth: 25 + (2x5) = 35m of chain/ rope combination and for 10m depth it would be 45m. If I am expecting bad weather , I add 10m.

Thanks, I guess that would make me ok for good weather.
Will look into the Knox.
Not keen on putting it on the bow roller- spoils the lines and more weight forward over a rather low volume bow.

Incidentally my friend’s heading to the Scillies tonight on a 28 footer - with 3 anchors onboard

 

[Yealm]

I used a 10Kg Delta and (I think) 60m chain when I had a CO32, but that was partly because of the surveyor warning me that Wales and the Bristol Channel was an area that required particularly robust ground tackle. It was my first boat and I was cautious, and back then, the Delta was the bees knees. Only dragged once and that was harmlessly somewhere in a deep part of Fishguard harbour. Still not sure whether it was lack of scope or poor holding. Otherwise all was well, including Scillies and some bits of Scotland.

The only point I'd question would be your (laudable) aim to never anchor in more than F4. It's fine as an ambition but unless you've managed to grab the controls of the weather machine, you're going to find yourself anchored in > F4 almost regardless of intentions. It might be F4 when you drop the hook and the forecast may be delightful, but you can be sure that one night you'll be woken by the wind whistling through the rigging.

Yes- i think I’d only ever drop the hook in stable weather systems F3 max (? 90% of Summer nights?), assuming it possibly might ‘blow up’ to F4.

 

[CAPTAIN FANTASTIC]

Thanks, I guess that would make me ok for good weather.
Will look into the Knox.
Not keen on putting it on the bow roller- spoils the lines and more weight forward over a rather low volume bow.

Incidentally my friend’s heading to the Scillies tonight on a 28 footer - with 3 anchors onboard

I was in the Scillies a few weeks ago during the storm Evert, on the anchor, in depth of approx 3m. The anchor and the chain held well, to my relief. I too had 3 anchors; one deployed (Kobra), and two on the stand by (Fortress and Britany).

 

[ortac]

Plus one for knox

 

[Neeves]

I've worked out my little anchor locker will just fit a Rocna 10kg, 15m chain and 30m rope (Contessa32).

Confession - I don't know how big a Co32 anchor locker might be -

But you will get more in it if you use smaller chain and smaller rope (small in terms off diameter). I jest - but if you are considering 10mm chain and 3/4" rope then it might be much tighter than if you use something smaller -

So fess up!

The ground tackle is a package - not just an anchor.

Personally if I were retrieving (by hand) - I'd look at 6mm chain and an aluminium SARCA Excel (from Jimmy Green). The Knox is an excellent anchor, you will be supporting local steel makers and galvaniser - and the money you invest in UK industry will support the chiropractor should you have a weak back. I'd also suggest a Viking, as it is lightish (in terms of its performance, hold vs weight), but it has a roll bar (like the Knox) and might not fit in the anchor locker. The aluminium SARCA Excel has a removable shank (like the Spade). Another option - so much choice would be Kobra which has a folding shank and might fit better. In terms of cost - the Kobra and Viking will be the cheapest, The Knox somewhere in the middle and the Excel (not forgetting aluminium Spade) - might induce a re-think - but think of your back.

Jonathan

 

[Yealm]

Confession - I don't know how big a Co32 anchor locker might be -

But you will get more in it if you use smaller chain and smaller rope (small in terms off diameter). I jest - but if you are considering 10mm chain and 3/4" rope then it might be much tighter than if you use something smaller -

So fess up!

The ground tackle is a package - not just an anchor.

Personally if I were retrieving (by hand) - I'd look at 6mm chain and an aluminium SARCA Excel (from Jimmy Green). The Knox is an excellent anchor, you will be supporting local steel makers and galvaniser - and the money you invest in UK industry will support the chiropractor should you have a weak back. I'd also suggest a Viking, as it is lightish (in terms of its performance, hold vs weight), but it has a roll bar (like the Knox) and might not fit in the anchor locker. The aluminium SARCA Excel has a removable shank (like the Spade). Another option - so much choice would be Kobra which has a folding shank and might fit better. In terms of cost - the Kobra and Viking will be the cheapest, The Knox somewhere in the middle and the Excel (not forgetting aluminium Spade) - might induce a re-think - but think of your back.

Jonathan

Thanks so much Jonathan great info!
I think I’ve got 8mm chain in the garage..

 

[Stemar]

I had 8mm chain on Jissel but, following a serious illness, I was finding it too heavy, so I swapped for 6mm. There was no noticeable difference in holding power.

If you're concerned about strength, it has a breaking load of around 1.5 tonnes. I can't imagine any circumstances short of a survival storm in which a CO32 would put anywhere near that much stress on a chain, especially if you make up a decent snubber, nor can I imagine any anchor holding unless wedged in a rock.

 

[doug748]

I sold the Knox anchor to ansarkit. To be exact it will fit the CO32 anchor locker but it is very tight, tricky to retrieve and will only come out one way. This is made worse if the chain shifts under it at sea, when it can be impossible to remove without shifting the chain beneath the anchor. Not great if you are in a hurry.

The Rocna I now have is similar but a little better. I have 45mts of 8mm chain which meets most coastal circumstances in the Channel except, at times, around the bay of St Malo. I have some lengths of nylon for these times but don't attempt to stow them in the chain locker. I dig them out as needed, which is seldom; they serve double duty as long lines for rafting etc.
I may be selling the Rocna ( has anyone had more anchors than me?) as I now have a new Epsilon which, being quite short, is a much better fit but as yet it is still in the shed.

I vaguely recall trying a Manson Supreme, for fit, once and I do recommend you look at that. I believe Force 4 will sell you one and refund if it does not suit.

Personally I dislike anchor rope and it would be a right pain in a smaller anchor locker, stowing 30m and 15m of chain under a 10Kg Rocna would be a work of art.

.