Mantus rode

[weavis]

I have a Technovorm filter coffee machine. It is better than most others. Today I put a high plain Colombian coffee in it which I roasted 4 days ago.

It is my third cup.

Ergo more is better!!

er.. as you were... thread drift.

[Q Xopa]

Originally Posted by ramblinrod

I disagree.

I believe I am just standing behind my convictions supporting them with facts, logic, reasoning, and practical examples.

I don't believe I miscomprehended anything anyone has posted.

I understood it all perfectly well.

Some of the things that some people posted were just wrong.

The collective wisdom is that the general rule for anchoring is that for a temporary anchor use 3:1, overnight fair conditions, 5:1, and storm conditions, 8:1 scope or better.

That a few are claiming that 3:1 is good enough for storm conditions in 100 ft of water, well I'm sorry, that is not collective wisdom. It may be a set of circumstances that ended turning out favourably, but what if it didn't. What if I'm correct, and they were just lucky, and the next time, not so much?

In my opinion that is just false hope and blind faith, that could very well hurt someone if they accept it as true, and use that as their general rule instead.

I fully admit that I am not likely to roll over and accept something someone or even a group claims is correct when I know it to be false.

So if anyone wishes me to not stand my ground, all they have to do is discontinue challenging the ground I stand on, unless they can actually incorporate something of merit into their challenge, that I can accept as new ground to stand on, and I'll be glad to.

I enjoy learning new things; I don't enjoy discarding facts for fiction, so I am not likely to ever do it.

I disagree with-

"The collective wisdom is that the general rule for anchoring is that for a temporary anchor use 3:1, overnight fair conditions, 5:1, and storm conditions, 8:1 scope or better".

You are probably correct that this maybe the accepted definition in the broader lesser informed boating community.

That is a good definition, but is an old over simplified version in that it makes no reference to DEPTH. or anchor type, rode etc.

The current collective wisdom, that Im aware of, by enthusiasts on forums like CF, recognises that there is more to anchoring than scope.

Specifically that a lesser scope will give a similar holding at a greater depth. I agree that is a correct concept with additional weight of chain even at a lesser scope.

If I understand you correctly, this seems to be the specific point you disagree with?

Obviously, as has been said by others, if we have the opportunity to maximise it then yes why not.

However in the real world, as in the example mentioned, 5:1 at 100 ft, ie 500ft rode is not always possible, practical, or even safe. Swing room, locker capacity etc.

But agreed, you do what you want.

However, advising others as a professional service provider, like a doctor that doesnt explain the risks and options involved in a treatment isnt really acting responsibly.

[Q Xopa]

Originally Posted by weavis

I have a Technovorm filter coffee machine. It is better than most others. Today I put a high plain Colombian coffee in it which I roasted 4 days ago.

It is my third cup.

Ergo more is better!!

er.. as you were... thread drift.

Love it!
3 cups of Columbian would have me wired. 6 cups would have me posting non stop, no sleep for a week.
More really is better!

Sorry,

Carry on.

[weavis]

Originally Posted by Q Xopa

Love it!
3 cups of Columbian would have me wired. 6 cups would have me posting non stop, no sleep for a week.
More really is better!

Sorry,

Carry on.

I finished the entire pot...

[skipmac]

Originally Posted by ramblinrod

Oh, I thought that was adequately answered by another who correctly advised you that there is more to scope than just straight line draw angle.

But my response would have been, "While the straight line angle difference may appear small, with increased scope comes increased catenary, which can contribute significantly to holding.

Should the forces required to pull out this catenary in longer scope be present, then every little bit of lower angle you can maintain on the stock is "ultimately" important to make sure you stay put instead of ending up on the rocks.

Guess you are too busy arguing to comprehend what I'm saying. I thought I made it clear more than once that the angles are calculated based on a theoretical ideal BUT I thought it would be clear to any reasonable person that in the real world they will be even smaller since it is impossible to pull a rode perfectly straight. So in the real world the difference in the angle of pull between 7:1 and 10:1 is even smaller than the calculations based on a perfectly straight rode.

Now read carefully. This means that the difference in the angle of pull between 7:1 and 10:1 is effectively zero IE negligible. It could not be measure in the real world so the the great benefit you claim going from 7:1 to 10:1 does not exist. NOTE: very, very rarely in some unusual situation or special circumstances (like anchoring on a reverse slope for example) there can be a reason to use a 10:1 scope but not as a standard practice.

[skipmac]

Originally Posted by ramblinrod

And if the force on the rode is great enough to remove the catenary from 10:1 scope, it is way better to have that straight line angle on the stock, than that of 9:1, 8:1, 7:1 or anything less, because quite frankly, you don't really know just how good the holding is or just what that angle can be for that bottom and what ever greater force you may experience, before that anchor pulls out.

One more time, look at the math. The difference in the rode angle in a real world situation between 7:1 and 10:1 is negligible and in the real world could not even be measured. Increasing the scope to 10:1 from 7:1 WILL NOT MAKE ANY PRACTICAL CHANGE IN THE ANGLE ON THE ANCHOR STOCK. It will not make a "straight line angle on the stock" any more than 7:1

IF as you keep claiming, the catenary could be removed (impossible, can't happen) the angle change is ONLY 2.5 DEGREES! in the real world the change is effectively nothing.

If you understood static and dynamic load calculations you would understand that difference in the pull on the anchor is for all practical purposes zero.

[skipmac]

Originally Posted by weavis

I finished the entire pot...

If I drank that much coffee I would have to anchor myself to the floor and it would take a 10:1 scope to hold me down.

[transmitterdan]

When anchoring in the Great Lakes maybe it is impossible to know the bottom conditions. But as we know from another famous thread on CF, in the tropics it’s a completely different matter. One can inspect the bottom and anchor condition easily most places where we like to cruise. If my Spade is buried in good holding increasing scope from 3:1 is actually a bad idea. Because long scope means more swinging and harder side pulls at the end of each swing.

There are no hard and fast rules in anchoring. It takes knowledge of your ground tackle and boat as well as conditions below. As others have said weather forecasts don’t come with guarantees. So be ready to change/move if conditions exceed your comfort level.

[Dockhead]

Originally Posted by transmitterdan

When anchoring in the Great Lakes maybe it is impossible to know the bottom conditions. . . .

Even for those cruising the majestic fjords of Lake Erie, there is no excuse for not knowing the bottom conditions, and no excuse for not knowing with a high degree of certainty what kind of holding your anchor will give you.



You know very well about the bottom conditions, even without the crystal Caribbean seas, from the character of the land around, the contour of the bottom, the chart (after all), and what your depth gauge tells you as you circle around your possible anchoring spot.


And then the way the anchor feels as it goes in and you back down on it, tell you everything else you need to know.


"Feeling the Rode
"Bottom characteristics will be telegraphed up the anchor rode while you are setting the hook; experience teaches you the code. Placing your hand/or foot on the chain or rode will enable you to feel the interaction between anchor and ground as it digs in. If you feel vibration and an occasional bump coming up the chain or rode, the anchor is sliding on the bottom. If the boat drags back slowly and then the anchor digs in, the bottom is probably composed of soft mud over firm bottom. With good holding—hard deep sand, for instance—the anchor will slide a short distance and then dig in hard.

"Rock- or coral-infested bottoms require a bit more interpretation. The anchor will slide and bump along, catching occasionally and then breaking loose as the load builds.

"An anchor that is well-dug-in sends a high-frequency, constant vibration up the rode or chain. Any other vibration indicates that the anchor is slipping. With enough power in reverse, the angle of the rode is straight and remains constant. If it tends to flex, that is another indication that your anchor is moving on the bottom."

Dashew, Practical Seamanship


If you have to anchor on short scope, it pays to be particularly careful about how the anchor is set. We spent the whole summer last summer in no less than 15m of water and no more than 3:1 scope. I would drop and back down on the anchor as many as 10 times before being satisfied that it was in the right bit of bottom and well and truly buried in the bottom.


I always back down over at least 10 minutes starting with low revs and gradually increasing to redline, 100 horsepower pulling on the anchor. If the anchor will hold 100 horsepower, it is set. If not, we go around again. The whole process may take more than an hour, but it's due diligence in challenging conditions.

[Dockhead]

Examples of places where short-scope anchoring is essential, even if there is a storm.





"Charcot Havn - Anchorage
70O 46’.90N 25O 27’.81W
Large glacier bay situated on the East side of Milne Land. The glacier has receded a mile or more up the valley leaving extensive mud banks and a heavy burden of silt in the bay. The beach appears to shelve steeply, anchor 104m offshore in 15m, good holding. Another anchorage is in the North West corner off a stream good holding in 15m, 100m offshore. Beware of mud banks!" CA Cruising Guide

Note how close to the shore you have to be according to this – to find 15m of water. 7:1 scope would swing you up onto the beach; more than 3:1 would definitely put you aground if you swing. The boat in the photo (not ours; from the CA cruising guide) is in 15 meters of water yet is only a couple of boat lengths from the shore. Actually we could not find 15m of water here amongst the shifting, uncharted, steeply sloping mud banks. We found a shelf in about 25m of water about 150m from the shore. Even with 3:1 scope, we were pretty sure we would be aground if the wind shifted, so we didn’t dare use more scope than that, although we had more chain. And this is the best place to anchor within about 30 miles of this spot.







"Harefjord - Anchorage
70O 57’.462N 28O 03’.865W
Some difficulty has been experienced in finding a good place to anchor here but it is a beautiful place surrounded by red mountains and icebergs galore. A walk ashore to the hill overlooking the calving glacier at the head of the fjord gives a perfect panorama. . . A narrow creek appears to offer shelter from icebergs but it is too deep to anchor until the bottom rises suddenly to rocks at 2.3m. Anchorage may be found further east with good holding but a lot of rocks reducing swinging room, precarious!" CA Cruising Guide



You can see from the photo (not our boat; from the CA cruising guide) how tight this anchorage is, even tighter than the one where we decided to weather the storm described before. And not perfect shelter, either. We did not risk this one.




Note well the relationship between shelter, and limited swinging room. This situation is common even in less extreme places. In a storm, you must have shelter if you are going ride it out at anchor. Very often where there is good shelter, there is not space to put out as much scope as you would like. It is essential to understand how far you can go in shortening scope, and a sailor who is not capable of safely using a short scope in a storm if it's necessary, that is, understanding exactly how much is needed and how much he can get away with, really shouldn't be in charge of a vessel, at least not anywhere more than a few hours from a marina.

[ramblinrod]

Originally Posted by Dockhead

Even for those cruising the majestic fjords of Lake Erie, there is no excuse for not knowing the bottom conditions, and no excuse for not knowing with a high degree of certainty what kind of holding your anchor will give you.



You know very well about the bottom conditions, even without the crystal Caribbean seas, from the character of the land around, the contour of the bottom, the chart (after all), and what your depth gauge tells you as you circle around your possible anchoring spot.


And then the way the anchor feels as it goes in and you back down on it, tell you everything else you need to know.


"Feeling the Rode
"Bottom characteristics will be telegraphed up the anchor rode while
you are setting the hook; experience teaches you the code. Placing your
hand/or foot on the chain or rode will enable you to feel the interaction
between anchor and ground as it digs in. If you feel vibration and an
occasional bump coming up the chain or rode, the anchor is sliding on the
bottom. If the boat drags back slowly and then the anchor digs in, the bottom is probably composed of soft mud over firm bottom. With good holding—hard deep sand, for instance—the anchor will slide a short distance and then dig in hard.

"Rock- or coral-infested bottoms require a bit more interpretation. The
anchor will slide and bump along, catching occasionally and then breaking
loose as the load builds.

"An anchor that is well-dug-in sends a high-frequency, constant vibration
up the rode or chain. Any other vibration indicates that the anchor is
slipping. With enough power in reverse, the angle of the rode is straight
and remains constant. If it tends to flex, that is another indication that
your anchor is moving on the bottom."



Dashew, Practical Seamanship

You go ahead and tell yourself that you know precisely how well your anchor will hold each setting.

Interestingly, I've been around long enough to know that you don't.

The tragedy (waiting to happen) is that you are espousing to others that you do, and they may actually believe it.

If only we could bottle your clairvoyance to benefit the rest of us with your supreme knowledge.

Now that's a product I could market:

New and improved "Instant Set", let's you set it and forget it, first time every time.

No more "Feeling the Rode"!

No more "Diving on the anchor"!

Just apply "instant Set", drop the hook, and your done.

But wait, there's more.

For the next 15 minutes, we'll add a can of "Perma hold" to your order for just $5.99 in additional shipping and handling.

Imagine,

- Never needing to set an anchor alarm ever again.
- Waking rested every morning despite hurricane force winds the night before.
- Never having to lie to your crew, "We're fine".

Because with new Insta-Set and Perma-Hold you'll absolutely know that your anchor will stay put no matter what happens.

Call now! Limited Supply! Only 3 easy payment of $99.99.

Warranty dependant that the conditions be exactly as indicated in Dockhead's "magic" algorithm, and proof of such required in writing from an accredited laboratory with your warranty claim.

Warranty limited to the cost of the product; sorry about your yacht.

[Sailmonkey]

Rod,

Your inability to see gray is the reason you’re being blasted like you are. There is nuance here that’s either going right by you or that you’re purposely ignoring to protect your agenda.

[skipmac]

Originally Posted by ramblinrod

You go ahead and tell yourself that you know precisely how well your anchor will hold each setting.

Interestingly, I've been around long enough to know that you don't.

The tragedy (waiting to happen) is that you are espousing to others that you do, and they may actually believe it.

If only we could bottle your clairvoyance to benefit the rest of us with your supreme knowledge.

Now that's a product I could market:

New and improved "Instant Set", let's you set it and forget it, first time every time.

No more "Feeling the Rode"!

No more "Diving on the anchor"!

Just apply "instant Set", drop the hook, and your done.

But wait, there's more.

For the next 15 minutes, we'll add a can of "Perma hold" to your order for just $5.99 in additional shipping and handling.

Imagine,

- Never needing to set an anchor alarm ever again.
- Waking rested every morning despite hurricane force winds the night before.
- Never having to lie to your crew, "We're fine".

Because with new Insta-Set and Perma-Hold you'll absolutely know that your anchor will stay put no matter what happens.

Call now! Limited Supply! Only 3 easy payment of $99.99.

Warranty dependant that the conditions be exactly as indicated in Dockhead's "magic" algorithm, and proof of such required in writing from an accredited laboratory with your warranty claim.

Warranty limited to the cost of the product; sorry about your yacht.

Did you not even read the previous posts, in particular the one where Dockhead discussed how he sets his anchor, including a discussion and quote on feeling the rode?

Sincerely I think you need to relax, take a deep breath and try to address this more rationally instead of entrenching in an emotional, defensive posture that seems to cause you to ignore logical and factual responses to your position. I think many have agreed with some or even many of your points but take exception to the extremes to which you take them. Maybe stop to consider that you may have the theories correct but are applying them beyond where they work in practice?

[Delfin]

Originally Posted by ramblinrod

One person in this thread called anchoring an art.

I almost fell of my chair.

It's a science, pure and simple; the application of physics to hold a known object in place against variable forces.

I think I agree with you on this. However, what no one seems to be able to get you to understand is that the number of variables in anchoring go beyond your dogmatic insistence that increasing scope to the max possible is the essence of good seamanship. The kind of anchoring that has kept my vessels safe for 40 years of cruising and that keeps others with far more experience than I have on this thread safe for years involves the interplay of a whole bunch of factors that your lack of experience may have hidden from your consideration, including

1. Seabed conditions
2. Type and size of rode
3. Snubbed or unsnubbed rode
4. Swinging room
5. Anchor weight
6. Anchor design
7. Expected and possible conditions
8. Hull design
9. Setting technique
10. Seabed slope
11. Scope

Those are just the ones that come off top of mind, others no doubt have more, and while scope is one of them it is only one. Arguing that it is the most important because more is always better is uninformed. A heavier anchor is always better than a lighter one, right? So what kind of a jerk would I be if I implied that you were (a. a fool; (b. endangering your passengers; or (c. stupid as you have called others because you refuse to carry a 400# Fisherman anchor? Answer: I would be you Rod.

Originally Posted by ramblinrod

And the science tells us, that more scope is better, and 3:1 scope may not be enough to stand up to those forces; so to carry only enough rode for that amount of scope is completely illogical. Bad science.

When people start to introduce straw men arguments they have truly lost the argument. No one on this thread has suggested that one should only carry 3:1 scope's worth of rode. They've simply tried to point out the physical, scientific and rational reasons why your position is daft. Please stick to what people actually say, and not what you pretend they said. You might be taken more seriously if you do.

[Dockhead]

Originally Posted by ramblinrod

You go ahead and tell yourself that you know precisely how well your anchor will hold each setting.


. . . .

The tragedy (waiting to happen) is that you are espousing to others that you do, and they may actually believe it.. . .

So you think anything under 8:1 scope in strong weather -- not considering the anchor, the bottom, the shelter, etc. -- is a "tragedy waiting to happen"?


Sorry to inform you, but this is standard practice, among experienced sailors. Same practice followed by Dashew, Morgan's Cloud, everyone who anchors in places where there aren't easy answers.


Just because you don't know how to do it, doesn't mean it's unsafe.

If you don't know how to feel the anchor setting and read the seabed, you're not ready to go to sea.

And anyway, logically, if you can't know at all how your anchor is going to hold, then what difference does more scope make? It still might not hold. How do you know your anchor is big enough?

All this silliness is starting to become boring.