Anchor chain rode

[billyfish]

What do we think the minimum amount of chain to rope rode is required for say a 30 foot 5 ton boat in 6 mts of water. I have 35 mts of 8mm chain with 10mts of rode with a 10kg hook. I was thinking of going down to say 10mts of chain or even less.

 

[BabaYaga]

What do we think the minimum amount of chain to rope rode is required for say a 30 foot 5 ton boat in 6 mts of water. I have 35 mts of 8mm chain with 10mts of rode with a 10kg hook. I was thinking of going down to say 10mts of chain or even less.

On a boat just slightly smaller (29 foot 3.6 ton) I have settled on 20 metres of 8mm chain, followed by 14mm octoplait nylon, 45 metres of length. I think it gives a good balance, as there will rarely be any rope on the sea bed. Most times I will have all the chain out plus anything from a few metres of rope up to several tens of metres, depending on conditions. Still lifting the chain plus anchor from maximum anchoring depth (say 15 metres) is manageable without a windlass.

 

[michael_w]

I work on 3 x depth of water. Maybe add a bit on for luck, so 2Om. Depends slightly on anchor and conditions. eg. a Bruce is an excellent short scope anchor and can be snugged up quite tight in good holding ie sand or sticky mud. Dunno about the fashionable anchors rocna et al.

No doubt someone will be along to say 'Unless you veer 60 meters with a 50 Kg fiisherman anchor you will die'

 

[Neeves]

There is no definitive anchor.

Most modern anchors,Knox, Spade Excel, Odin will work at short scope, 3:1, you might need a bit of patience initially to get them to engage but once the toe starts to bury they will set securely. All bets are off if its blowing 45 knots.

Don't use dyneema - it floats.

The idea is to have the rope off the seabed - but once a year and a sand seabed you would have no issues.

If you don't know or have any worries about the seabed you really don't want the rope abrading on rock with the rode taut. Similarly you don't want to be using textile in mud (the ideal seabed for a Bruce - it will be a devil to wash off.

If you are retrieving by hand and have 8mm chain I'd dump the 8mm and add a longer length of 6mm. You simply don't need the strength of 8mm with a 5t boat and certainly don't need the catenary effect with a decent length of nylon in use.

Jonathan

 

[Refueler]

What do we think the minimum amount of chain to rope rode is required for say a 30 foot 5 ton boat in 6 mts of water. I have 35 mts of 8mm chain with 10mts of rode with a 10kg hook. I was thinking of going down to say 10mts of chain or even less.

Why are you changing ? is it due to the weight carried fwd ? Or effort needed to retrieve on board ?

I'm a Ships guy .. so chain is my goto ...

But in keeping with the yottie role ... in your position .. I would stick with present setup .. or if you really want to change .. I would have at least 20m of chain and then similar or longer of rope rode.

At end of day ... whatever is claimed ... Catenary is IMPORTANT .... not only in terms of snatch - but also the direction of pull on the anchor of whatever design you choose.

BUT as a short time stop .. ie an hour or so fishing or grab a lunch ... I use one of those reels with braided tape ... with a short 1m length of chain ... I would never leave the boat while its used .. but its handy for the short stop.
I'll be honest - I'm not exactly too comfortable leaving a boat on its hook anyway .. so tend to lay out more than 3:1 ...

 

[Stemar]

Jazzcat (8m cat) has about 10m of chain, plus lots of rope. My last boat (24ft) had 17m, plus rope, but the chain was a lot smaller. Both work just fine, though I liked the longer length of chain better. Even so, as I get older, 17m of 8mm chain plus a 10kg anchor is just too heavy.

If weight is the issue, I'd consider going for a smaller chain, in a higher grade if necessary for strength, as part of a mixed rode.