Sorry, anchor question

[FlyingDutchman]

Last Sunday we were out on the lake and as the weather was nice we decided to anchor for a quit afternoon.
Boat is a 7.2 meters mobo (see avatar) weight about 1.800 kgs.
Ancor setup is a 5 kg Brittany anchor + 2m chain + 15 m rope.
Water depth is 3 m and the wind is force 4. Anchoring ground is muddy.

After half an hour the anchor works loose and the boat drifts towards the shore.
A quick engine start saves the situation but we are fed up with this anchor.

Can anyone advise what to do or buy?
Limitations are that the anchor locker is small (maximum shaft length of the anchor about 50-60 cm) and that the whole setup should not be too heavy as SWMBO handles the anchor as she is not confident with steering wheel and throttle.

I have thought about a Fortress as they are small and light but would it really do the job?

Any input highly appreciated!

 

[capt_courageous]

Hi
Try a Bruce ( or chinese copy ). You seem a bit short of chain. It helps to have quite a lot to hold the anchor down till it digs in.

 

[wiggy]

I also had a brittany, as much use as a chocolate tea pot, a Fortress would seem to be the answer, aluminium with very good general holding power. Wait for the tyrade from all those anchoring experts!!!!! /forums/images/graemlins/laugh.gif

 

[Dipper]

I agree that you are short of chain/rope. Don't forget that when you calculate how much is needed, you are 'losing' some of the length in between the bows and the water surface.

 

[Amari]

My Fortress works well, usually as a kedge over the stern. very easy to lift. The manufacturers state weight is not important. I have just bought an aluminium Spade but not tried it yet. General concensus seems to be that modern designs better than Bruce etc., but much vitriolic disagreement on previous threads!

 

[KenMcCulloch]

[ QUOTE ]

Boat is a 7.2 meters mobo (see avatar) weight about 1.800 kgs.
Ancor setup is a 5 kg Brittany anchor + 2m chain + 15 m rope.


[/ QUOTE ]
That seems to me a very tiny anchor for a boat of that size, and not enough chain to keep the load on the anchor horizontal.

 

[Brierley]

I would agree that your anchor is very small for the size/weight of boat. Our boat is similar in length/weight to yours and we have a 7kg aluminium Spade with 10m of chain and 20m of rope. The aluminium spade is the lightweight version - the steel equivalent for surface area is 15kg!

We have a small lightweight fortress for lunch stops which just squeezes into our tiny anchor locker (I dismantle the spade when it's not in use and store it below) which has 8m of chain and as much rope as I could fit into the locker as well ! It will hold once set, but will not set in weed as it is too light. I also would not trust it for an overnight stop as I'm not at all convinced it would reset as the boat turns with wind and/or tide.

 

[Lakesailor]

On my 6 metre sailyboat I had a small Danforth (copy) and 5 metres of chain plus loads of nylon.
On the lake I never had a problem and kept the anchor for my smaller 5 metre mobo. Very light and easy to handle (don't trap your fingers though) and never needed more than one attempt to hold.

 

[Channel Ribs]

I agree with Lakey, a danforth clone with some more chain would suit your situation.

 

[FlyingDutchman]

Thank for all your answers!

I agree, 2 m of chain is not much, but I don't think SWMBO could handle much more. I have 15 m of rope attached to the chain. Should this not be enough as the typical water depth is between 2 and 3 metre?
I thougt about a Fortress 1.8 kg FX7 as I think it would fit in the locker and it is light weight.
I just want to avoid buying another anchor that doen't work and only gives frustration!

 

[mortehoe]

I\'m really surprised that the Rocna man hasn\'t chipped in ....

With respect your chain/rope setup isn't worth a candle. Your chain/rope scope should have been at least 6:1 for your boat in a F4 and even then it might have gone walkabout ... All chain is better, and all chain hitched to a Rocna is the bees knees .... You'd have only needed 3.5:1 scope ... Buy a Rocna toot de sweet and save all your future agro /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif

 

[Drascomber]

With your high windage hull IMHO if you are always going to anchor in soft mud in very sheltered water the Fortress option should be OK but you really should try to use 5 meters of chain - 10 would be better.

I you ever anchor on anything else, even hard sand, and can't use a heavy anchor then you need a more modern design that is more likely to dig in. Look for something with a sharp point and a weighted nose - like a Delta or Spade. One that comes apart may solve your storage issue.

Brittany just doesn't seem to work well in small sizes.

 

[cliffordpope]

Simple mud-weight, for a muddy bottom?

 

[photodog]

You need more chain and line, dont forget the distance from the top of the boat to the waterline, and are you measuring the depth from your keel? (Ie what your sounder is probably showing after adjustment?)

Anchor choice and weight is important, but the amount of scope you have out, is more so...

Your sitting on 3:1 roughly with mostly rope, we tend to sit on 5:1 minimum with all chain, in a boat with less windage.

Lots of other suggestions for good pointy anchors, but I would add a LOT more chain. If your in 5 meters you really need (IMHO) at least 5 meters of chain and 30 meters of line.

Thats 7:1 with a lot of rope.

We carry 50 meters of all chain.

Get a windlass if its a concern. Manual ones are good and dont cost much.

Remeber the adage; If in Doubt, Let more out!!

Once you get the hang of the anchoring thing, its great.

 

[jimbaerselman]

Your dragging was caused because the anchor wasn't dug in, and couldn't be with so little scope.

The maximum pull angle at the sea bed for a Britany to dig in is 10 degrees; that's 6:1 from your stem head when the line is stretched. In 3m water your stem head depth would be 4 to 4.5m - so you'd need a scope of 24 - 27m.

Given that weight is a problem, just add exra rope. The anchor is small, but should be OK for F4. After anchoring, always check the holding by running in astern - this also digs the anchor in properly.

If you want to anchor in anything over a F4 you may need a larger anchor - and given the weight problem, you'd have to consider an Aluminium Alloy job. Gives you extra holding for the same weight.

Start with the longer rope though . . . and test once you've anchored to check it's working . . .

 

[Gunfleet]

I agree with Clifford. The Norfolk Broads is full of boats sporting simple mud plugs. Why should a Dutch lake be different?

 

[FlyingDutchman]

Thanks again for all your answers.
Can anyone explain what a mud plug is?
It seems that I really should have more chain, but because of the weight I don't really want to go that way.
Would a Fortress bring any improvement or would it work just as bad as the Brittany?

 

[bbg]

I'll agree with Jim on this. A lot of people seem to be ignoring your comments re weight. Assuming you decide to make weight your limiting factor, you seem to be left with three options:
1. Choose a different material for the anchor (i.e. alloy) so you get more surface area for the weight
2. Choose a different design for the anchor, so you get better holding power for the same weight
3. Increase your scope - i.e. lengthen your rope

Or a combination of 2 or 3 of the above. Personally I think I might go for the alloy Spade, which I think can be taken apart, and much more rope.

However, it is also possible not to make weight such a limiting factor by - getting your wife to be more comfortable on the controls (once she is comfortable there she will be much happier than on the foredeck) and/or installing a windlass.

Good luck.

Edit - you don't need "all chain" as some people say. It would be better, but much heavier. I believe Nelson's navy used to anchor with all rope - i.e. no chain at all. I won't say they never dragged or their ropes never broke, but they found a way to make it work (most of the time) without chain - so can you.

 

[Lakesailor]

On the subject of the weight that the crew will have to haul up.

The amount of chain you have will not greatly change the weight she'll have to haul up as the depth of the lake is 3 metres. So even allowing for the scope she'll never be lifting more than about 6 or so metres free of the lake bed. as she hauls in the chain sits in the anchor well or on the deck and the only bit that is being hoisted is between her hands and the lake bed. At the point the anchor is freed the boat will be almost over the anchor so it'll be a straight lift of 3 metres of chain plus the anchor.

Same as at present.

I can't see how a longer chain will alter the situation.

On the lake, if weighing anchor on my own I set the boat going gently in the direction of the anchor (easy when we only have wind to consider, no current) and haul like hell. I usually find the boat is above the anchor at the critical moment and it breaks free easily. If not, disengage gear, fall back, and try again.

 

[FlyingDutchman]

Thanks again for all your input!
I will consider all aspects and make a decision.