When the rope meets the windlass!

[capt-couillon]

Hello again LeeV.... Sorry I wasn't clear in my earlier post. The 50-250 no windless set up is what I use, but I am still using a "warp to chain splice" regardless. Works well in a windless if you got one, but it's also very strong, resistant to chafe, and small diameter makes it easy to feed down the deck pipe.

Regardless of the weight, I love the 50' chain. Always a good set even in soft bottoms with the extra weight keeping the anchor down for a good attack angle. As I am usually anchored in 8-10' (when I can) I essentially have an "all chain rode". As an official "geezer" hauling in 50' of chain in the morning is not a bad exercise program After securing the chain with a stopper, I usually run a 15' 3strand line as a "snubber" leaving 3' or so of chain slack so I am not listening to it clack in the bow roller all night.

Next time the rode gets replaced I hope it will be with 8 strand plait (square braid) for the advantages listed in earlier posts. The caveats against braided rode apply to standard (low stretch by design) single of double braid used for running rigging. Plaited or "square braid" has plenty stretch to reduce shock load.

[thinwater]

Originally Posted by UNCIVILIZED

And on most splices, during class, Brion suggested doing a splice several to get familiar with a technique, & then throwing them out. As everyone will do a better job on splice #7 than they will on their first one.

+10

I consider myself a fair hand at splicing, and I threw out the first 3 and tested the 4th to failure.

This is not an easy splice, but neither is it black art. Keep the lay tight and try to balance the tension best you can.

It's worth it. It NEVER jams. Also note the strength of rope vs. chain that some windlass makers recommend. For example, the Lewmar V4 recommends 3/8 chain and 5/8 rope. If that is G43 chain, the rope is only 66% of chain strength. Ouch. The reason, I believe, is that a conventional splice won't pass the windlass if the right rope size were used!

Yes, a rope rode see less stress than chain (stretch), but it also wears faster, so AYBC recommendations are the same for both.

[UNCIVILIZED]

This splice isn't weak, actually, despite how it seems at first glance. As you have 4 sections of the rope's lay bearing the load, where it meets the chain. A comment made by Brion while teaching them. Along with the hair gel one, which drew a few snickers. But it does work for keeping the lay of the rope tight & firm while putting the splice in.

[David B]

Originally Posted by thinwater

Google "irony splice." It is a long splice for chain-to-rope. Basically, only 2 strands go through the chain and the other is mated like a long splice. A little trickier to make (strands need to be balanced and everything snug). but just as strong and very smooth through the windlass.

So given that it is three strand rope, and only two of the strands go through the chain link, that must (with no allowance for weakening due to the bend or abrasion), reduce the strength of the rope by 33%.

[UNCIVILIZED]

Originally Posted by UNCIVILIZED

This splice isn't weak, actually, despite how it seems at first glance. As you have 4 sections of the rope's lay bearing the load, where it meets the chain. A comment made by Brion while teaching them. Along with the hair gel one, which drew a few snickers.

Originally Posted by David B

So given that it is three strand rope, and only two of the strands go through the chain link, that must (with no allowance for weakening due to the bend or abrasion), reduce the strength of the rope by 33%.

Call the shop & ask...
Then send them a fiver.

Or, read about it in Brion's own words http://briontoss.com/spartalk/showth...rony+splice%22

[David B]

Thanks for the link - all makes sense, re the other points, but still can't get away from the fact that there are only two of the three strands going through that link.

Put it another way. Take a length of braid, double it, then loop the doubled rope through a pad-eye and pull until it breaks. That will be (in theory at least)double the breaking point of a single length of rope. Even though four lengths are going up to the pad-eye, only two are going through the pad-eye, same as with this rope to chain splice.

[StuM]

Originally Posted by reed1v

For those who only anchor in calm seas and mild winds, use whatever you like. If you want to prepare for stormy conditions in less than perfect holding grounds, you need to make sure your anchor rode has the ability to stretch under load to absorb the surge shocks that would otherwise get transferred directly to your anchor; potentially pulling it out of its set. An all chain rode is best since the weight of the chain acts as a natural "spring" to take up the extra loadings. Eventually even that may not be enough so you also use elastic cords that will elongate under really heavy loads, like 1000 pound loads. That should provide an extra degree of slack.
Its also important to remember you want to reduce shock loads not only to the anchor but also to whatever your rode is fasten to on deck. We saw a Hudson Force Fifty's windlass get pulled out of the fore deck well during a hurricane. All chain had reached its limit and the extra loading was enough to rip out the windlass. Big boats like tugs use chain wrapped around tractor tires which are then fastened with more chain to deck bollards. Have seen those tires really elongate during a typhoon in Hong Kong.

So bottom line boys and girls. Do not go long distance cruising. Stay near shore and you will be find with braided lines, short chains, and tiny anchors.

More drivel from the usual source.

[thinwater]

Originally Posted by David B

Thanks for the link - all makes sense, re the other points, but still can't get away from the fact that there are only two of the three strands going through that link.

Brain Toss pull tested them. So did I. The strength is the same.

Remember that on a double braid splice, only the cover carries load on one side (the core is not tucked deep enough to bear weight).

Case closed.

[David B]

Defies physics, but we will leave at that until someone can throw light on this.
Thanks for the contribution - will remain perplexed for now

[UNCIVILIZED]

Originally Posted by David B

Defies physics, but we will leave at that until someone can throw light on this.
Thanks for the contribution - will remain perplexed for now

Not really. As if you have 4 falls of a line extending out towards infinity, how strong will it be? 1.333x greater than the 3-strand line.

And when a spliced line, especially a 3-strand line, breaks, how often does the line break within the splice? AKA the section of the line which is now 6 falls thick. Such as if you were to loop the full thickness of such a line through the end of a piece of chain, & then splice it.
My money is on such a spliced line breaking in the line's body, aft of the splice. Not in the splice itself. Probably because the line's weaker there. Or rather, it's strength is unaltered there. Unlike in the section where the splice's tucks are.

[Cottontop]

Originally Posted by David B

Defies physics, but we will leave at that until someone can throw light on this.
Thanks for the contribution - will remain perplexed for now

Perplexes me as well. But look at page 57 of this rigger's handbook, which indicates that a basket hitch with vertical legs has double the working load limit of a single sling.

http://www.ihsa.ca/PDFs/Products/Id/M035.pdf

[David B]

Originally Posted by UNCIVILIZED

Not really. As if you have 4 falls of a line extending out towards infinity, how strong will it be? 1.333x greater than the 3-strand line.

And when a spliced line, especially a 3-strand line, breaks, how often does the line break within the splice? AKA the section of the line which is now 6 falls thick. Such as if you were to loop the full thickness of such a line through the end of a piece of chain, & then splice it.
My money is on such a spliced line breaking in the line's body, aft of the splice. Not in the splice itself. Probably because the line's weaker there. Or rather, it's strength is unaltered there. Unlike in the section where the splice's tucks are.

Hmm - don't know if I'm not getting it or what ever, but if you take those four falls, and fix each one individually at a pad eye, then totally agree - you will have 1.33 times more strength than three falls.

HOWEVER - those falls in this example are not independently fixed - they are relying on each other. Put it another way - pick up the pair on one side and fix to a bollard, so they are horizontal. Now take the pair on the other side and pull horizontally and the two ropes are just passing through the pad eye, with no force or deformation due to the pad eye (the pad eye is now just sitting in the middle of two taut ropes. Those two taut ropes are only twice as strong as one taut rope - not as strong as four taught ropes (two ropes either side of the pad eye).

Now let them drop again as infinite falls. You still have just two ropes - not four ropes. The two ropes just happen to be looping through a pad eye (and are a little weaker due to the sharp bend).

So - a length of three-strand rope is as strong as a length of three strand rope. Un-lay one of the strands and it is now 66% as strong. Loop those two strands through a pad eye (or chain link), and then do what you like with them - you still only have two strands taking the load. Whether those two strands are tied off to the pad eye, or back down into the lay of the three-strand rope to form a splice (and therefore two strands up, and two back down to the splice). There is no getting away from the fact that there are only two strands of a three strand rope taking the load.

I have no problem with the splice - just that only two thirds of the rope is going through the chain link, and therefore at that point, the rope is only two thirds as strong (actually less due to the sharp bend, but we ignore that for now).

Interesting discussion

[David B]

Originally Posted by Cottontop

Perplexes me as well. But look at page 57 of this rigger's handbook, which indicates that a basket hitch with vertical legs has double the working load limit of a single sling.

http://www.ihsa.ca/PDFs/Products/Id/M035.pdf

Now that's an interesting manual - thanks !

[thinwater]

Originally Posted by David B

Hmm - don't know if I'm not getting it or what ever, but if you take those four falls, and fix each one individually at a pad eye, then totally agree - you will have 1.33 times more strength than three falls.

HOWEVER - those falls in this example are not independently fixed - they are relying on each other. Put it another way - pick up the pair on one side and fix to a bollard, so they are horizontal. Now take the pair on the other side and pull horizontally and the two ropes are just passing through the pad eye, with no force or deformation due to the pad eye (the pad eye is now just sitting in the middle of two taut ropes. Those two taut ropes are only twice as strong as one taut rope - not as strong as four taught ropes (two ropes either side of the pad eye).

Now let them drop again as infinite falls. You still have just two ropes - not four ropes. The two ropes just happen to be looping through a pad eye (and are a little weaker due to the sharp bend).

So - a length of three-strand rope is as strong as a length of three strand rope. Un-lay one of the strands and it is now 66% as strong. Loop those two strands through a pad eye (or chain link), and then do what you like with them - you still only have two strands taking the load. Whether those two strands are tied off to the pad eye, or back down into the lay of the three-strand rope to form a splice (and therefore two strands up, and two back down to the splice). There is no getting away from the fact that there are only two strands of a three strand rope taking the load.

I have no problem with the splice - just that only two thirds of the rope is going through the chain link, and therefore at that point, the rope is only two thirds as strong (actually less due to the sharp bend, but we ignore that for now).

Interesting discussion

A standard second year engineering problem.

Yes, the ropes are connected to each other. Is the force on a tug of war line, where two teams are each pulling with 1000 pounds = 2000 pounds? No, of course not. The force on the line is 1000 pounds, whether connected to a fixed anchor or connected to another team. Same thing here. Thus, the tension on each line is 1/4 the total load, whether connected to each other or to separate anchors points. It could not have any other value and maintain a balance over the link. Obvious.

There is some loss around the short radius of the eye, but not so much because the strands have room to flatten out, reducing the effective diameter and strength loss.

So while it may seem counter intuitive, it is basic statics.

[David B]

People seem to be missing the point that there are only two ropes, not four. Take two ropes and have a tug of war until they break. Now take another two ropes, loop them around a lamp post (chain link) and have another tug of war until they break - you have again broken just two ropes, not four.