How much chain?

[Zimbali]

I have a Jeanneau SO 45.2 with a Lofrans 1000w electric windlass. Currently she has a 45lb Simpson Lawrence anchor and 30m of 10mm chain. I would feel happier with more.

Does anyone have any idea how much chain the windlass will handle comfortably?

 

[TiggerToo]

we have 55m and the Lowfrans 1000w handles it OK.

 

[Malish]

I'm a bit puzzled by the question - surely the amount of chain the windlass will handle is dictated by the depth of water you anchor in, the size of chain and the angle of the chain from the boat to the bottom (ie do you assist the retrieval process by gently motoring forward?), and I suppose the size of your battery. The amount of chain on the bottom or in the anchor locker does not really matter.

 

[temptress]

HI,

We have a SO47 and had 110m of chain but this was too much weight in the bow. I reduced the chain to 70M and have an additional anchor warp of 150m to either add to the chain or set another Anchor on ( I have 20M of chain and 2 spare anchors stored more centrally and aft in the boat).

The max lenght is determined by how much space you have to stow it and the boats ability to carry the weight.

BUT how much do you need? What sort of crusing do you do? Typically you should never need more than 5 time the depth on chain (many people will often use less). So if you are anchoring in say 10m of water and you have a 10m tidal rise you should never need more than 100m but will probably be fine in nearly all conditions on say 60m.

 

[tome]

We have 60m calibrated chain on a Lofrans 1000W windlass, but don't fully understand what you are asking

 

[theforeman]

i suppose the only sensible interpretation is what length of 10mm chain plus 45kg anchor will the windlass cope with in a straight lift from the seabed. ( i`m assuming that the propellor would be used to break the anchor out ).

 

[AndrewB]

With 30m of chain you are anchoring in at most 10m of water so the greatest load you have had to retrieve is 10m of chain, a 45lb anchor, plus the force needed to break the anchor out.(Although, as Theforeman says, the engine will do most of the work breaking out, an upward tug on the windlass may also be needed).

You don't say what size chain you are using but I would expect 8mm. My guess is that a 1000w unit will struggle to raise your chain in anything over 20m of water. So you would never normally need more than the amount of chain necessary for anchoring in that depth. Maybe 80m, depending on what maximum scope you tend to allow - quite a load for that yacht. A rope-chain combo might be preferable.

 

[Dipper]

You need to know the pulling power of your windlass. In general terms, your windlass can handle ground tackle which weighs one third of its pulling power which allows for a safety margin. The weight of the ground tackle is the weight of the anchor plus the weight of the chain/rope when roughly vertical. This assumes you motor forward to take most of the strain off as you shouldn't use the windlass to haul the boat forward.

Obviously the weight of the ground tackle depends on the depth of water you are anchored in.

The Lewmar web site shows the calculations.

 

[kengill]

Why not use the 30metres for a kedge chain and warp set up and have as much chain as you can get in the locker without snagging for the main.

 

[gianenrico]

Zimbali, I have a 40 footer but also the Lofrans 100watt. My choice has been to have 75 meters of Grade 70 8mm calibrated chain, which has a working load far superior to the std 10mm, and at same total weight I embarked 30% more lenght; as I moor either in marinas or wild spots (in this case I tend to arrive early enough to choose the best spot, I pay out as std 7 to 10 times the depth; anchor is a 20 KG bruce Type Trefoil.
This summer we sustained repeated F7 winds but had no problem whatsoever. The first night I did the watch, then discovered the functions of Raymarine wireless Smart Controller, set up alarms on depth variations excedding 1 meter and wind alarm over 35 knots: I was awken a couple of times for some strong gusts but that was all; 3 monhulls and one 45' cat moved away during the night.
The Lofrans can pull a lot, so this is not really the bottleneck in the mooring system.
Cheers,
Gianenrico

 

[Anonymous]

Re: How much chain? - Raymarine alarms

[ QUOTE ]
The first night I did the watch, then discovered the functions of Raymarine wireless Smart Controller, set up alarms on depth variations excedding 1 meter and wind alarm over 35 knots:

[/ QUOTE ]That's interesting. Sounds very useful. I have the Raymarine handheld ST600R and haven't come across an alarm function and it isn't shown in the manual yet I was told by a rep at last year's Barcelona show that this is functionally identical to your wireless version. Does anyone know whether the ST600R can give depth and max wind alarms?

 

[hylass]

To determine the optimal amount of chain lead, consider making a statistical estimate of the average depth of water you plan on anchoring in, and calculate chain lead length based on the results.

For example, during the last seven and half months, we spent 129 days anchored in 61 different anchorages. The mean water depth was 21.3’ (6.50 m.) and the scope 5/1. The total length of the mooring line was about 98.5’ (30 m.), of which 77’ ( 23.5 m.) was lying on the bottom (30 - 6.50 m)

Therefore, we believe a length of about 25 meters of chain is acceptable.. and then ROPE directly spliced on the chain...

 

[Talbot]

I reckon that the best way of making sure you have as much chain as possible is to try lifting chain and anchor together, if it is easy, get more chain, if it is really difficult but possible, chain is about right, if it is impossible, either shorten the chain or buy a mechanical windlass.

based on ability to recover anchor and chain when in deep water.

personally I moved to a manual windlass when the back started to moan, then worked out my normal depth of water for anchoring went 3:1 and added a bit to round up and finished with 30m of chain (+50m of octoplait) that way I dont normally have to mess around using the chain/rope splice arouind the windlass and thus maintain the strength in the rope for occassions when it is needed.

 

[jimi]

I've got 30m of chain with 50m of warp spliced on. I reckon that'll cope in most situations. The only problem is the splice which needs to be carefully fed through the windlass or it can jam

 

[claymore]

I think ths simplest answer is that your winch will handle as much chain as you have - so perhaps you should be basing this on the size of your anchor locker and as others have pointed out, the likely depths of the waters in which you might be anchoring.

 

[davidbains]

I agree with Talbot especially on a light boat.
Since we rarely anchor in more than 25ft I have just over 25mtrs of 8mm chain with another 20mtrs of octoplait spliced to a shackle so it can easily be removed from the chain. More rope could be added but has never been necessary.
This means you rarely have to assist the shackle and splice through the windlass, and means you are not carrying around lots of chain that will never see the water.
Additionally, if you should lose an anchor under a rock ledge as I did this summer, at a depth too deep for safe snorkelling, not that working on jammed ground tackle is safe anyway, you don't lose a lot of unused chain as well.
It's more important I think to carry a second anchor and chain of sufficient size and scope to hold in a thunderstorm ( as we had to in 36kts the next night!).
This one can be a Fortress to save more weight.

 

[awol]

[ QUOTE ]
.... wild spots (in this case I tend to arrive early enough to choose the best spot, I pay out as std 7 to 10 times the depth; ... I was awken a couple of times for some strong gusts but that was all; 3 monhulls and one 45' cat moved away during the night.


[/ QUOTE ]

I'm not surprised they moved with you veering around the anchorage on that length of rode.

 

[GMac]

[ QUOTE ]
I have a Jeanneau SO 45.2 with a Lofrans 1000w electric windlass. Currently she has a 45lb Simpson Lawrence anchor and 30m of 10mm chain. I would feel happier with more.

Does anyone have any idea how much chain the windlass will handle comfortably?

[/ QUOTE ]

A lot of the production boats use a 'bare bones' model winch to keep the costs at bay. This is common amongst many winch and boat builders. There is no problem with that unless you want to seriously up size your rode.

While Lofrans are a damn good winch, one with a 1000W motor on a 40 + footer running 10mm is far from the grunty end of the scale. I'd think about putting rope on the back of the chain to keep the rode weight down and keep reasonable winch performance. That assumes you have a Auto rope to Chain model of course or don't mind manually swapping between gypsy and the capstan.

Note: 95% of most winch manufacturers listed specifications use what you may would call 'artistic lisence' and would only be reached in very ideal situations. There is no 'standard' test or procedure for getting the performance figures amongst the manufacturers. Treat all loads and speeds listed with a degree of caution and certianly don't expect to get them on your average boat.