Joining anchor warps.

[JohnGC]

For my main anchor, I currently have 30m of 8mm chain spliced to 25m 3-strand hawser laid line; up to now that has been fine.

But this year I'm planning to visit the Channel Islands and have decided to replace the 3-strand with 50m of Octoplait.

I want to keep the old line to extend the warp length if needed; I don't want to connect it to the Octoplait permanently because it will only be used in exceptional circumstances and I want to keep the amount of line in the anchor locker down. (In fact I'd simply of bought a longer length of Octoplait.)

I've been considering putting an eye-splice with thimble in both the Octoplait and 3-strand so that they can be joined by a shackle. I'm interested to hear options on that what other options there may be.

My windlass is chain only so that doesn't need to be considered.

John

 

[thinwater]

For my main anchor, I currently have 30m of 8mm chain spliced to 25m 3-strand hawser laid line; up to now that has been fine.

But this year I'm planning to visit the Channel Islands and have decided to replace the 3-strand with 50m of Octoplait.

I want to keep the old line to extend the warp length if needed; I don't want to connect it to the Octoplait permanently because it will only be used in exceptional circumstances and I want to keep the amount of line in the anchor locker down. (In fact I'd simply of bought a longer length of Octoplait.)

I've been considering putting an eye-splice with thimble in both the Octoplait and 3-strand so that they can be joined by a shackle. I'm interested to hear options on that what other options there may be.

My windlass is chain only so that doesn't need to be considered.

John

I like to hear why interlocking eyes would not work. Thimbles and shackles are not recommend for JSDs, for example, due to increased risk of failure (the thimble can move). A slight pain with 50M, but probably not much slower than getting the tolls to put a shackle together.

On reason I thought of this was for sailors that use a capstan, or if you had to use a winch for some reason; the eyes would feed more smoothly.

Just thinkin'. I have done it this way with shorter warps; it seems easier and safer.

 

[prv]

Personally I'd just leave the ends plain and make a double sheet-bend on the rare occasion it was needed.

Pete

 

[neil_s]

Another vote for a sheet bend - very simple to tie and hold very well.

 

[vyv_cox]

How are you going to transfer any type of rope to chain in the windlass? With a vertical axis windlass the only way is to splice the rope to the chain. With a horizontal axis it may be easier, dependent on the route the rode takes and the size of the hole it passes through.

 

[JohnGC]

How are you going to transfer any type of rope to chain in the windlass? With a vertical axis windlass the only way is to splice the rope to the chain. With a horizontal axis it may be easier, dependent on the route the rode takes and the size of the hole it passes through.

Our manual windlass only has a chain gypsy. I just haul the line by hand and wrap the chain around the vertical shaft windlass when it comes up. Best Mate nudges the boat forwards under engine so I don't have to drag the boat. With 30m of chain I don't foresee me trying to haul up my new Knox 13kg anchor by hand even in the CIs.

In windy and bouncy conditions some care is needed to avoid trapped fingers or a strained back but I don't find it difficult.

I'm leaning towards the sheet bend although I'd want to add stoppers or seizings.

John

 

[Tranona]

When I had a spliced rope on my main rode it had an eye on the bitter end with a light line to attach to the fixed eye bolt. If I ever needed to add anything I would have attached it with a bowline through the eye. I currently have 50m chain but no rope spliced on. Chain is attached to the fixed point with a shackle and my extra 30m rope has an eye on one end to attach to the shackle after removing from the fixed point.

 

[lw395]

I use interlocked bowlines, i.e. a bowline in each rope, formed into a reef knot.
I think there may be a better name for this hitch?

 

[vyv_cox]

Our manual windlass only has a chain gypsy. I just haul the line by hand and wrap the chain around the vertical shaft windlass when it comes up. Best Mate nudges the boat forwards under engine so I don't have to drag the boat. With 30m of chain I don't foresee me trying to haul up my new Knox 13kg anchor by hand even in the CIs.

In windy and bouncy conditions some care is needed to avoid trapped fingers or a strained back but I don't find it difficult.

I'm leaning towards the sheet bend although I'd want to add stoppers or seizings.

John

With a manual windlass you have plenty of options. On my kedge I have Octoplait with eye splice and thimble shackled to the chain. This would not pass through an ekectric windlass of course.

 

[thinwater]

In addition to no loosing 1/2 of the line strength in a knot, the other reason I like interlocked splices is that it handles smoothly; should it grind on the topsides or deck, no harm. It's less likely to catch a finger. I can put it on a winch. and there is NO chance of it coming un-done. Maybe knots are easier... if they don't jam. But probably not the more complex knotting schemes.

 

[jdc]

Two points:

1. I'd really not worry about losing 50% strength. Have you studied the breaking strain of the warps? Probably around 7 tonnes, so even if 'only' 3.5 tonnes you will never put that on your anchor, and it will never hold if you do.

2. The sheet-bend, even if double, is not a good knot for this. Ashley did a series of tests with bends where the force is repeatedly applied and released - much like an anchor - and came to some conclusions and published them in his book. The sheet-bends fare badly as they untie themselves after a surprisingly small number of reversals (try it if you don't believe me: only about half a dozen will untie a single sheet bend, and about 28 iirc a double. The Carrick bend fares better and is what's traditional in the uk at least, but the Zeppelin is better, and a variant as reported by Ashley even better (>100).

 

[thinwater]

Two points:

1. I'd really not worry about losing 50% strength. Have you studied the breaking strain of the warps? Probably around 7 tonnes, so even if 'only' 3.5 tonnes you will never put that on your anchor, and it will never hold if you do.

2. The sheet-bend, even if double, is not a good knot for this. Ashley did a series of tests with bends where the force is repeatedly applied and released - much like an anchor - and came to some conclusions and published them in his book. The sheet-bends fare badly as they untie themselves after a surprisingly small number of reversals (try it if you don't believe me: only about half a dozen will untie a single sheet bend, and about 28 iirc a double. The Carrick bend fares better and is what's traditional in the uk at least, but the Zeppelin is better, and a variant as reported by Ashley even better (>100).

1. I've studied anchoring a lot (many articles and a book coming out). The key point with strength is that nylon does very poorly above the WLL, which is only about 12% of BS according to ABYC and most engineering tables. So with a 7-ton line, now anything over 7 x 50% x 12% = 600 pounds now becomes a very real concern. That ain't much in a real storm (probably about 60 knots for the OP's boat), so I would be worried about knot strength. That said, rodes nearly always part from chafe, not fatigue, and nearly always somewhere around the bowsprit or roller.
2. I didn't want to point that out but yeah, sheet bends are not absolutely reliable in cyclical loading, and this knot needs to be.

 

[JohnGC]

There are some though provoking comments, thanks.

The reason I’m considering this at all is being caught out in deepish water in a storm. Being able to increase the scope in such circumstances could be helpful. Under those conditions ease of handling, strength and wear are all significant factors.

Some pros and cons then;

• I don’t like the idea of using a shackle without thimbles in this situation. Wear is my concern.
• Thimbles could move and cause wear themselves. Maybe less than a shackle directly on rope? What’s a JSD?
• Interleaved soft splices are an interesting idea although I’d need to thread 30m of 3-strand though an eye in the Octoplait. I’ll think about that some more but the idea appeals. I’ll try a dry run with figure of eight loops and see how easy it is to thread.
• I wouldn’t tie a knot in this situation without adding stoppers or seizing. I’ve seen too many climbers’ bowlines starting to undo. The exception is a double fisherman’s, but then I’d never get it undone again.
• I will look at alternative knots, but they need to be ones I won’t forget how to tie if a bit rushed.
• As for grinding the join over the deck or fittings; I can’t imagine a situation where it would be impossible to let out or take in a little warp to move the join away from the chafe point.
• Reduction in strength due to joining was taken into account when buying the rope. After all, a rope with no knot or splice isn’t a lot of use.

Tranona. Is your bitter end shackle attached to a hard point directly or via a cord you can cut? I wonder how easily you could ditch the anchor in an emergency. EG another boat out of control and bearing down on you.

John

 

[jdc]

...The reason I’m considering this at all is being caught out in deepish water in a storm. ..

Fair enough, but a little in conflict with your original post which said "But this year I'm planning to visit the Channel Islands... "

A storm (F10) will simply not happen in summer in the C.I. without days of warning! A force 7 is about all you will get I think, so, really, I think your plan to extend the warp will be just fine as the anchorage may be a bit deep at high water due to the large range. If a real storm is forecast, go to France asap and put in to a good port like St Malo, or coma scuttling back to Torbay (14 hrs?).

 

[JohnGC]

Fair enough, but a little in conflict with your original post which said "But this year I'm planning to visit the Channel Islands... "

A storm (F10) will simply not happen in summer in the C.I. without days of warning! A force 7 is about all you will get I think, so, really, I think your plan to extend the warp will be just fine as the anchorage may be a bit deep at high water due to the large range. If a real storm is forecast, go to France asap and put in to a good port like St Malo, or coma scuttling back to Torbay (14 hrs?).

Not quite.

Going to the CIs is the reason I've replaced 25m of 3-strand with 50m of Octoplait giving me 80m without extension.

But since I will still have the 3-strand, I want a method of using it should the situation arise and I want that method to stand up to a storm even if I don't plan to be in one. My CI trip doesn't feature (particularly) in that.

John

 

[thinwater]

There are some though provoking comments, thanks.

The reason I’m considering this at all is being caught out in deepish water in a storm. Being able to increase the scope in such circumstances could be helpful. Under those conditions ease of handling, strength and wear are all significant factors.

Some pros and cons then;

• I don’t like the idea of using a shackle without thimbles in this situation. Wear is my concern.
• Thimbles could move and cause wear themselves. Maybe less than a shackle directly on rope? What’s a JSD?
• Interleaved soft splices are an interesting idea although I’d need to thread 30m of 3-strand though an eye in the Octoplait. I’ll think about that some more but the idea appeals. I’ll try a dry run with figure of eight loops and see how easy it is to thread.
• I wouldn’t tie a knot in this situation without adding stoppers or seizing. I’ve seen too many climbers’ bowlines starting to undo. The exception is a double fisherman’s, but then I’d never get it undone again.
• I will look at alternative knots, but they need to be ones I won’t forget how to tie if a bit rushed.
• As for grinding the join over the deck or fittings; I can’t imagine a situation where it would be impossible to let out or take in a little warp to move the join away from the chafe point.
• Reduction in strength due to joining was taken into account when buying the rope. After all, a rope with no knot or splice isn’t a lot of use.

Tranona. Is your bitter end shackle attached to a hard point directly or via a cord you can cut? I wonder how easily you could ditch the anchor in an emergency. EG another boat out of control and bearing down on you.

John

2. Jordan Series Drogue.
3. Remember that this is a rare event, probably only a few times a year. My extensions are much shorter, only 20-30M each; I find these easier to handle. I have a full length spare rode as well.
4. I was surprised that no one mentioned stoppers.
6. No, of course you wouldn't leave the join where it was grinding. But in the process of deploying or recovering, there is always chance. I like not having to worry about it.
7. A splice does not reduce strength more than 5%. Most knots weaken the rope by 40-50% and this is NOT allowed for in standard rode selection tables.

 

[AntarcticPilot]

I'd simply tie them together, using a carrick bend with the ends seized to the standing part. The Carrick bend is reputed to be the strongest bend, and Ashley specifically recommends it for this use.