What is Too Much Rode?

[44'cruisingcat]

Originally Posted by robert sailor

My question is why are you so called experienced sailors hanging out on this site today when you should be sailing. We have a good excuse..cold front going through with the normal north winds, squalls and rain..what's yours????

SE change went through here in the early hours this morning. Squalls and rain. But we're out sailing anyway....

[Jim Cate]

Work is a dirty four letter word ending in K, Forum rules say such language is not allowed, so stop with it!

And while we're not out sailing today, we are at anchor in one of the most beautiful bays in the world, the sun shines in between squalls, yesterday there was f/c snow down to 900 m and hail in thunderstorms... and it is mid summer here!

Jim

[thomm225]

Actually, I'm thinking work is a good thing.......especially for your brain.

At work, we don't talk at length on such things as anchoring which most growing up on the coast learned to do as children or teens

Living in an apartment, I get to go to work. I get to stop by the boat morning and night and stay on it whenever I please or stay here or my home 70 miles north.

I get to go to the gym and the mall occasionally to shop, enjoy mall food, watch people, and go to a movie maybe

I couldn't imagine simply being anchored on a boat with nothing to do but boat stuff. That would be tough to deal with.

Weekends, it's car/jeep maintenance, movies, travelling. The library. Books. The Wright Brothers memorial is less than 2 hours south so I tend to visit a bit

My thought is a man should never retire. If on a sailboat, sail. If you aren't sailing, you should do something else. Hike. Build RC Planes. Join a gym. Volunteer .....

In the book, Call Of The Wild, when the old dogs were taken out of the traces, they'd still run along with the sled as long as they could. I'm thinking for many of us this is the way to go, but to each his own......

https://babel.hathitrust.org/cgi/pt?...iew=1up;seq=21

[james247]

Originally Posted by a64pilot

I’m sitting in 25 kts of wind, anchored in mud. I did set the anchor, but only backed down at 1500 RPM, cause it’s mud.
25,000 lb boat, 40 kg Rocna, eight feet of water.
Initially put out about 50 ft of chain, started to drag after an hour or so, out out another 25, I think I still drug, so put out out another 25’.
Total 100’ of chain in eight ft of water, seems excessive, but want to stop the drag.
Brings up the question though, I’m sure there is a point of dimensioning returns, but at what scope does it become counter productive or does it? Meaning is there a point that more equals less holding?

Your response was quite seaman like. However the only reason left is that your anchor was fouled. I would suggest to pick it up and reset it. The fouling could clear in retrieval or may be obviously still fouled. Some time excessive amounts of rode gives the impression of dragging where in fact you are sailing about on the rode. A gps anchor watch would prove this to you.

[valhalla360]

Originally Posted by 44'cruisingcat

Cruisers forum does often look like a contest to see Who can make the most ridiculous statement.

So let's look at these entrants....

Me: Letting out more chain will make you LESS likely to drag anchor.

You: Letting out more chain will make you MORE likely to drag anchor.

Well clearly there's no contest. I bow to your greatness.

Now you are just making things up.

I never said anything of the sort. Below is the original exchange:

Quote:
Originally Posted by 44'cruisingcat View Post
Every bit of chain out is less weight on the boat, so less load on the anchor...
Not sure if that is true. The boat weighs less but that should mean it sits higher in the water which means more windage which increases the loads.

In the end, 50lbs of chain, is probably such a small amount, you would be hard pressed to tell any difference in the loads.

[44'cruisingcat]

Originally Posted by valhalla360

Now you are just making things up.

I never said anything of the sort. Below is the original exchange:

Quote:
Originally Posted by 44'cruisingcat View Post
Every bit of chain out is less weight on the boat, so less load on the anchor...
Not sure if that is true. The boat weighs less but that should mean it sits higher in the water which means more windage which increases the loads.

In the end, 50lbs of chain, is probably such a small amount, you would be hard pressed to tell any difference in the loads.

Well, you said letting out more chain will increase the loads. (OK, you tried to water it down by saying it would be a small increase.)

Surely ANY increased load means more likely to drag? Thus, more chain out = more likely to drag.

It is amusing watching you trying to back away from your previous statement though.

Getting back to the OP's question. Given there's enough room, I don't believe there is ANY point at which letting out more chain becomes counter productive. Just chain on it's own exerts considerable resistance. Try dragging 20m of chain through wet sand or mud some time.

[valhalla360]

Originally Posted by 44'cruisingcat

Well, you said letting out more chain will increase the loads. (OK, you tried to water it down by saying it would be a small increase.)

Surely ANY increased load means more likely to drag? Thus, more chain out = more likely to drag.

It is amusing watching you trying to back away from your previous statement though.

What's really amusing is your lack or reading comprehension. You missed the word "but" in the second sentence implying that it balances against the effects of lowering the weight of the boat.

But hey, you keep trying to back pedal and add more misinformation as no where did I say or even imply "more chain out = more likely to drag".

[44'cruisingcat]

Try to at least be honest. You SAID more chain out increases windage which increases loads.

I'm not interested in what you reckon you "implied".

[valhalla360]

Originally Posted by 44'cruisingcat

Try to at least be honest. You SAID more chain out increases windage which increases loads.

I'm not interested in what you reckon you "implied".

No, I said siting higher in the water increases windage which increases loads.

But (remember that word you missed in your reading) that balances against the boat being lighter which is why specifically didn't give a definitive answer in fact I said "I'm not sure that's true." Hardly a definitive statement that more chain out increases loads.

I think this is enough thread drift. If you want to make up things that I didn't say, have fun.

[44'cruisingcat]

Originally Posted by valhalla360

No, I said siting higher in the water increases windage which increases loads.
.

Sitting higher caused by what?

[james247]

Originally Posted by a64pilot

In light winds, yes.
The dual 5/8” is for heavy winds, I guess I ought to come up with an in between solution. The dual line is just regular docklines, so maybe 40 feet? Unsure actually, but way longer than 15 feet, by at least double.

If I single line, that of course has me tying off to the bow cleat, and the line will come off at an angle to the bow.

I get tired of all of the hypnosis about the required amounts of rode. This varies greatly based on the size and style of the anchor and the size of the chain or rope rode.
Many of the calculations quoted come from history when the best form of anchor was the admiralty patent anchor. This anchor is still the best in heavily weeded areas as it actually digs through the weed while other styles slip through the weed filling the hook with weed.
The condition of the bottom is highly important. Surprising to some this is one of the reasons charts mark the nature of the bottom.
Most moorings are made up of a heavy lump of concrete and very little rode scope.
So enough chain and you will stop . A hook on the end is a bonus. The size of the chain is very significant. For many good reasons we tend to go with the lightest chain recommended for the size and weight of the boat. However anyone who goes to the next size up in both chain and anchor rarely drag. Sleeping is far better. Scope of chain in most conditions is only 3 or 4 to one.
But setting the anchor is of paramount importance drop the anchor to the bottom and only pay out chain after the wind or tide move you away from the anchor. When the desired amount of chain is layer do you the tie off and set the anchor. Reversing till the chain is stretched and the prop wash reaches the bow or beyond.
It's then time to tidy the boat check she has settled and have a sundowner or two

[thinwater]

Originally Posted by james247

I get tired of all of the hypnosis about the required amounts of rode. This varies greatly based on the size and style of the anchor and the size of the chain or rope rode.
Many of the calculations quoted come from history when the best form of anchor was the admiralty patent anchor. This anchor is still the best in heavily weeded areas as it actually digs through the weed while other styles slip through the weed filling the hook with weed.
The condition of the bottom is highly important. Surprising to some this is one of the reasons charts mark the nature of the bottom.
Most moorings are made up of a heavy lump of concrete and very little rode scope.
So enough chain and you will stop . A hook on the end is a bonus. The size of the chain is very significant. For many good reasons we tend to go with the lightest chain recommended for the size and weight of the boat. However anyone who goes to the next size up in both chain and anchor rarely drag. Sleeping is far better. Scope of chain in most conditions is only 3 or 4 to one.
But setting the anchor is of paramount importance drop the anchor to the bottom and only pay out chain after the wind or tide move you away from the anchor. When the desired amount of chain is layer do you the tie off and set the anchor. Reversing till the chain is stretched and the prop wash reaches the bow or beyond.
It's then time to tidy the boat check she has settled and have a sundowner or two

Holding vs. Scope at the Bottom

This has been researched with modern anchors, and the results are not so different from stockless anchors as you might think.

• The ratios are nearly independent of size, from 10 pounds to 2 tons.
• Yes, I do know the specific brands tested, but because there was a lot of scatter in the data, it did not seem beneficial to name-names.
• The graph is normalized for holding capacity; some of the anchors simply hold better than others.
• This is based on the lead angle at the bottom, not the scope. Polyester line was used instead of chain to eliminate catenary as a factor.

The complete story is here, including wind vs. scope and sand data.
https://www.practical-sailor.com/iss...t_12296-1.html

The point is, when anyone other than a pivoting fluke anchor manufacturer tries to say their anchor is great at short scope, they are trying to sell you an anchor. They are great at short scope only so long as the chain stays on or very near the bottom.

[Just Another Sa]

Originally Posted by 44'cruisingcat

Surely ANY increased load means more likely to drag?

Not necessarily. A better lead angle with very small increase in load will probably mean less likely to drag. See picture of post #117 above on effect of lead angle on max holding capacity.

However real world anchoring is much more complex than any static holding capacity test. It's entirely possible to have less max peak load at the anchor rode connection while the average load on a little longer time interval at the same connection is increased. Would that mean increased or decreased load?

How about if the magnitude of load is increased while the vertical component of the same is decreased due to lead angle change. That can be made true during statical testing. It's not at all clear if that means more or less likely to drag without knowing by how much load and vertical component changes and their initial values are, and anchor and bottom type play a significant role as well just like some other factors.

[Just Another Sa]

Originally Posted by thinwater

Holding vs. Scope at the Bottom

This has been researched with modern anchors, and the results are not so different from stockless anchors as you might think.

• The ratios are nearly independent of size, from 10 pounds to 2 tons.
• Yes, I do know the specific brands tested, but because there was a lot of scatter in the data, it did not seem beneficial to name-names.
• The graph is normalized for holding capacity; some of the anchors simply hold better than others.
• This is based on the lead angle at the bottom, not the scope. Polyester line was used instead of chain to eliminate catenary as a factor.

The complete story is here, including wind vs. scope and sand data.
https://www.practical-sailor.com/iss...t_12296-1.html

The graph is normalized for holding capacity; some of the anchors simply hold better than others.

1) Which means some anchor in the pic with a low %value might hold better than others of similar weight having curve above it, even at higher lead angle.

2) Too bad the pic does not show lead angles all the way to 90 degrees, as it is also important for an anchor to be able to lift off the bottom when it's time to leave. That percentage should drop way below 10% at 90 degree lead angle and that should hold true for all bottom types, not just for soft mud.

The point is, when anyone other than a pivoting fluke anchor manufacturer tries to say their anchor is great at short scope, they are trying to sell you an anchor. They are great at short scope only so long as the chain stays on or very near the bottom.

That pic does not support such claim, without knowing how high 100% holding capacity is for each anchor. See my point 1) above. Boaters don't need high percentage of max holding capacity at shorter scope, just high enough holding capacity at the lead angle they are using, even if the same anchor would hold much more at less angle.

[thinwater]

Originally Posted by Just Another Sa

1) Which means some anchor in the pic with a low %value might hold better than others of similar weight having curve above it, even at higher lead angle.

2) Too bad the pic does not show lead angles all the way to 90 degrees, as it is also important for an anchor to be able to lift off the bottom when it's time to leave. That percentage should drop way below 10% at 90 degree lead angle and that should hold true for all bottom types, not just for soft mud.

That pic does not support such claim, without knowing how high 100% holding capacity is for each anchor. See my point 1) above. Boaters don't need high percentage of max holding capacity at shorter scope, just high enough holding capacity at the lead angle they are using, even if the same anchor would hold much more at less angle.

The primary reason the data cut off was that the scatter became huge at large angles is because minor inconsistencies in the soil have a huge effect on suction at large angles; sometimes break out would be easy and some times it would not. But remember that a corollary of good short scope performance (like Fortress) is that breakout is more difficult. There is no way around this.

Yup, some anchors hold more. Obviously. Even then, it depends on the bottom--the top performers in soft mud weren't always the top performers in firm sand. So don't get too uppity about your favorite anchor. However, what is important is the trend, so we didn't name-names.

You can take away from this whatever you want. That's the nice thing about data. It is what it is.