Chain/rope combination for anchor cable

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memerys

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I need to extend my anchor scope for deep water anchoring and I'm thinking of using rope rather than additonal chain. I have a Lofrans electric windlass and normal chainpipe, and can visualise problems in getting the rope back into the chain locker when weighing anchore. Does anyone have experience of this set up and how it might or might not work?
Thanks
 
I have chain/rope and a windlass and it does cause a problem at the transition. There has been a thread on this before. My "solution" or "work-around" is to have a thin cord tied at one end and ready to put through the chain when the chain reaches the windlass gypsy. I then tug the cord and gain some more chain and tie of the cord leaving some slack chain at the windlass. I then drop the slightly loose chain into the gyspy so it engages correctly. Then untie the cord and continue with the windlass to heave in the rest. It is quite simple and doesn't take much effort if the conditions are reasonable. I leave the cord lashed in place when not being used.

It's not a very good description but hopefully you can get the idea.

Cheers,

Dave
 
Depends how often you hawlup and leave and then re-anchor. Crew considerations etc.

I generally singlehand on a boat of the same size and tend to anchor in two stages stage 1 chain and then stage 2 the rope section.

However my spliced joint will go through the windlass and hold withought problems at the transition.

I am not sure that I would want the ware and tear of the joint going through the windlass regularly though.

Is 25 mts of rope enough? I have used alot more in a blow.
 
Thanks Boatman, I too would effect a splice which would pass through the chain pipe and windlass, but how do you manage to get it back through to the bottom of the locker when weighing anchor. I assume any action with the rope section would have to be manual.
 
One problem with rope is that it doesn't self stow, as you're aware. However, it looks like you would have enough chain out to allow you to pause once the rope is on deck and feed it down the chainpipe. Then resume hauling the chain with the windlass. That's how we did it; not as slick as all chain but quite workable.
 
Anyone having issues with the spice means it's time to be re-done or done properly. There is no reason they should work well. I make 50 a week.

Use rope. It's easy, cheap, safer when you're a yacht and you have a built in snubber.

Just had a quick suss of the Alain Fraysse site (noted above) and for my R930 at 3:1 scope in a good seabed it says I should have an anchor in the 58kg range, at 9:1 scope a 12kg, using my existing rode. I used 40knts wind speed.

If I upsize my chain to 16mm I only need a 26kg one at 3:1. Mind you, I doubt I'll ever get the cow to sail with that much weight in the bow. If I did use that size chain there is no way I'd need to put an anchor on it anyway.

I'm only using a 4.5kg which holds like a taxman onto your wallet. Total system weight is 25kg odd (rope, chain and anchor). OK the anchor is Alloy but the steel version is only 9kg.

One of us is quite wrong, I wonder which one?
 
My solution is to open the chain locker hatch (it's on deck) reach in and take a bite of rope and keep tension on it as the rope passes through the windlass.
If you have a chain pipe and no deck access to the chain locker I can only suggest having 'competent crew' down below to pull on the rope /forums/images/graemlins/frown.gif
 
<<< One of us is quite wrong, I wonder which one? >>>

It's a very interesting question. Most manufacturers, and the Alain Fraysse site, use the ABYC data to calculate anchor weights, rode lengths and other information. The predicted loads in about Force 9 are in the thousands of kg. Conversely, the information measured by load cell, reported in the past few months in YM articles, peak at about 150 kg in Force 9. These are not one-off measurements, but continuously measured when at anchor by a charter boat over two years.

I can accept that the force on the anchor, rather than on deck, will be a little more, but certainly not an order of magnitude. It would seem that some of the assumptions made in the calculated versions are somewhat pessimistic. Note also that the calculated versions do not take wave action into account, whereas the measured ones, of course, are real and so do include waves.
 
[ QUOTE ]
the information measured by load cell, reported in the past few months in YM articles, peak at about 150 kg in Force 9. These are not one-off measurements, but continuously measured when at anchor by a charter boat over two years.


[/ QUOTE ]

I'm very surprised by this info,

After a strong wind, up to force 9 and over.. if you walk on the sea side looking at the desasters (trees , Torn publicity pannels, roofs..) it should be quite more than 150 kg??
 
I have the article in front of me now, January 2007 Yachting Monthly. The boat referred to is a Sigma 33C. The equipment used was an Anchorwatch, designed by Prof. John Knox, who I'm sure you are aware of. Load recorded in Force 9 is shown as about 135 kg.
 
The a very large amount of the variations would be down to the boat I'd guess.

You have a big cruiser with big full bows and masses of wires hanging off the mast you'll get big loads. If you have a fine bowed race yacht the loads would be a big pile less.

Most cruisers would have huge drag issues (wind wise) compared to most other boats. In a big blow this would create a lot larger load on your rode.

Chuck in the range of fizz boats you get and you'll have a wildly differing range of loads.

Hence I'm right when I say, anchor systems are very much a horse for courses thing and what maybe fine on Bobs XYZ50 is not good for Marys XYZ50. Well, I like to think I am anyway /forums/images/graemlins/smile.gif
 
Firstly, has the windlass got a combination rope/chain gypsy? If not, forget the rope, the windlass won't pull it up. If it has, you will find the instructions say you should only use 3-strand rope because multiplait is too soft for the gypsy to grip. There is a single chain and rope size for the gypsy which you must use. I think mine is typical (1000w windlass) with 8mm chain & 12 mm rope.

The instructions say you should back-splice the rope through the last link of the chain. I haven't tried the longer type of splice but I do occasionally get snarl-ups as the splice goes down the hole.

I have no trouble getting the rope to stow - the windlass stuffs it down the hole then the chain drops on top of it and flattens the pile. The only stowage problem I ever have is with the splice.
 
Ive got 30m of chain and 50m of multiplait. Only problem I've had is feeding the splice through the windlass, I just take it easy a link at a time and it OK. Stowage is no problem.
 
[ QUOTE ]
I think mine is typical (1000w windlass) with 8mm chain & 12 mm rope.

[/ QUOTE ]

Typical is 8mm chain and 14mm rope. 12mm rope goes with 6 or 7mm chain.

Oh and Lofrans love a nice 8 braid/octiplait/Square braid. They don't like nasty ones. They will run good 3 strands as well.
 
Alain - is there any reason why my Lewmar (horizontal) windlass instructions says don't use octoplat - use 3 strand? I prefer octoplat as it sits in the anchor locker easier.

Just taken over my new boat, and the anchor cable is only 50mtrs - so I need to do something about that.

Chris
 
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