Backing Down? Why Bother When Tide Changes

[sailorboy1]

Originally Posted by Delancey

I know anchor is set when the boat suddenly jerks to a stop and spills my drink. Diving on it confirms this.

How did the boat suddenly jerk to a stop if you didn't back down on it?

But jerking just means that the anchor caught, not that it set.

[Suijin]

Originally Posted by Delancey

This thread kills me. I basically ask, why back down an everyday non-storm anchor once it has been set in an area of good holding and strong reversing currents because you're not going to back down again every time the tide changes are you?

I mention I am so impressed with the way my new gen anchor routinely sets so quickly causing the boat to jerk to a stop. I also mention Panope's excellent videos which clearly show new gen anchors routinely pivoting in the sea bed under a reverse pull at 1.9 knots which is well within the current range I have been experiencing.

I am told by various anchoring experts that you must back down to ensure that the anchor is "properly" set because the boat jerking to a stop is not a fair indication. That if you don't do this you will only find out later when a storm comes (forget the OP was about everyday non-storm anchoring) that you didn't really have it set. That jerking stop was deceptive.

I am told that an anchor that is "properly" set by backing down will not likely turn due to the force of the tidal current, even though this statement is clearly contradicted by Panope's videos. Did you even watch them?

Lastly, I am told that an anchor-properly-set-by-backing-down-that-hasn't-rotated and is now 180 degrees backwards to a reversing current is BETTER than a set-but-not backed-down anchor that is rotated and correctly aligned to the pull.

Oh, except forget to mention unless there is a really big wind or a storm? You know, when you need you anchor the most but you backed it down in the WRONG direction?

Then presumably you are screwed because Panope did say he observed a 180 degree pull-out failure but we won't mention that! So much for the whole backing down theory. You can't have it both ways.

Haha. Keep it coming!

Your sarcasm is misplaced. Yes, a well set anchor will pivot in place, in most circumstances, if the direction of pull changes. I have not seen a single person argue against that. But that will only happen if the anchor is properly set in the first place.

If your boat "jerks to a stop" due to wind and current when setting the anchor, you can be assured of only one thing, and that is that at that moment it is holding against the current wind and tide. It may be partially set, just enough to stop the boat. You have no way of knowing anything beyond that.

I've had, as I mentioned earlier, experiences where my boat "jerked to a stop" after I dropped the hook temporarily, only to have it drag later. Yes that's anecdotal, but it's also empirical evidence that in some conditions you cannot have much confidence that your anchor is set unless you put adequate load on it.

It amazes me that this topic has generated such strong (and borderline rude) declarations that backing down is not necessary. No one is making you do it. Keep doing what you want to do. But to categorically claim it's not necessary, to those of us who have genuine experience with it's benefits, is absurd.

[rwidman]

Originally Posted by chala

............My experience with fully buried anchor set by backing with an engine is that the anchor is so well set that in a storm the anchor may not give and separate from the chain and this suddenly. On the other hand, dragging an anchor will give a greater chance of recovery.
................. Or the shank may get bent.

Am I to understand that this actually has happened to you? Or is it just something you fear will happen?

[Delancey]

Originally Posted by Suijin

Your sarcasm is misplaced. Yes, a well set anchor will pivot in place, in most circumstances, if the direction of pull changes. I have not seen a single person argue against that. But that will only happen if the anchor is properly set in the first place.

If your boat "jerks to a stop" due to wind and current when setting the anchor, you can be assured of only one thing, and that is that at that moment it is holding against the current wind and tide. It may be partially set, just enough to stop the boat. You have no way of knowing anything beyond that.

I've had, as I mentioned earlier, experiences where my boat "jerked to a stop" after I dropped the hook temporarily, only to have it drag later. Yes that's anecdotal, but it's also empirical evidence that in some conditions you cannot have much confidence that your anchor is set unless you put adequate load on it.

It amazes me that this topic has generated such strong (and borderline rude) declarations that backing down is not necessary. No one is making you do it. Keep doing what you want to do. But to categorically claim it's not necessary, to those of us who have genuine experience with it's benefits, is absurd.

However I may have set it, when I say it is set after the jerk-to-stop, I am confirming it is in fact set by diving on it. Set as in upright, level, and fluke fully engaged in the bottom.

Couple people have stated or endorsed a belief that current usually isn't enough for an anchor to pivot. Panope's videos would seem to contradict this.

Hey, I don't have all the answers. If I did I wouldn't be here asking. My recent anchoring behavior is new and a reaction to my recent experiences. I'm taking in others opinions. My behavior may change. As usual, lot's of folks have their own opinions. Sometimes they seem to contradict themselves.....

[Panope]

Delancey,

Thanks for the kind words about my videos. However, I think a distinction should be made between a boat that is MOVING at 2 knots with MOMENTUM vs. a boat that is STATIONARY in a 2 knot current.

In all but the most violent current reversals, a boat will GRADUALLY shift to the new position, and in this case, I agree with others who state that the force placed on an anchor due to current passing by a hull, is not enough to rotate a well set anchor.

That said, I do believe the violent, momentum based yanking that I have simulated in my tests are possible in real life on very rare occasions.

If one could somehow be certain that no foreign objects or unusual substrate is present, then your theory is probably sound. Without that knowledge, I think power settings with as much force as possible is the best choice.

Steve

[Delancey]

Originally Posted by Panope

That said, I do believe the violent, momentum based yanking that I have simulated in my tests are possible in real life on very rare occasions.

I'm not really arguing one way to another and I don't at all necessarily disagree with anything you have said as a whole. Rather I am taking a devil's advocate approach to try to understand something better.

Quoted above you do say these unfavorable results are possible. Anecdotal evidence suggests such occurrences are indeed very rare.

As you also mention you can't guarantee foreign objects or an uneven substrate don't exist.

To me this suggests that any time a once "set" anchor rotates, it can only be considered as a "newly" set anchor.

How many times does an anchor need to "re-set" until they set no more, assuming it continues to set as deep or deeper each time?

How can you guarantee this when you can never guarantee the bottom unless you back down each time?

I'm just asking.

Some of my recent experiences at a couple different spots have been with what I would call soft sand/mud bottom with +2 knot currents with contrary winds that oftentimes put the boat sideways to the current dragging a big wake down stream.

Some of it has included some wild jerking by being brought up as a result the contrary wind and current and not at all of the kind typically associated with normally swinging at anchor. It is apparent to me the anchor has rotated at least a couple times on a couple of two to three day stays in one spot.

[noelex 77]

There are basically two ways of setting an anchor under motor:

The first is to lay out the anchor chain, hopefully in a reasonably straight line. Then using the engine in reverse the force is gradually increased by increasing the revs. Typically for a sailboat, this ends in full reverse which is held for a period of time, perhaps 30 seconds or so. Setting is confirmed by the boat remaining stationary despite the increased force. This is the method I most commonly use.

The second method primarily uses the boat's momentum to set the anchor. The chain is laid out as in the first method, but the boat is allowed to develop a little speed. When the desired scope is reached the chain is secured. The boat continues to move backwards until the chain is tight at which stage a lot of force is applied to anchor. Hopefully the anchor digs in. The boat is brought to a sudden stop and the momentum of the boat applies a setting force. Setting is confirmed by the boat coming to a sudden, sharp stop and the bow dipping down.

The main problem with the second method is that it applies a strong, sudden force to an unset anchor. Anchors prefer a gradually increasing force. If you apply a high force to an unset anchor it will sometimes refuse to set, simply skipping along the bottom. However, modern anchors in a good substrate will usually set despite the difficulties. If you don't get the sudden stop and bow dip you know the anchor did not set and the anchor can be re-dropped.

There are a number of variations for this second technique. An improvement (in my view) is to keep the reverse speed low initially so the force is only slight. The boat will bounce forward and a second set can be done with more momentum. People that use this technique will often have several sets each with increasing force.

Other variations of the second technique include setting in a forward direction, or combining the first and second techniques.

With all these methods the aim is to dig the anchor into the substrate and also provide a test that the anchor is holding. Both techniques can work and surprisingly produce a similar depth of set if done correctly.

[Kenomac]

Originally Posted by Delancey

This thread kills me. I basically ask, why back down an everyday non-storm anchor once it has been set in an area of good holding and strong reversing currents because you're not going to back down again every time the tide changes are you?

I mention I am so impressed with the way my new gen anchor routinely sets so quickly causing the boat to jerk to a stop. I also mention Panope's excellent videos which clearly show new gen anchors routinely pivoting in the sea bed under a reverse pull at 1.9 knots which is well within the current range I have been experiencing.

I am told by various anchoring experts that you must back down to ensure that the anchor is "properly" set because the boat jerking to a stop is not a fair indication. That if you don't do this you will only find out later when a storm comes (forget the OP was about everyday non-storm anchoring) that you didn't really have it set. That jerking stop was deceptive.

I am told that an anchor that is "properly" set by backing down will not likely turn due to the force of the tidal current, even though this statement is clearly contradicted by Panope's videos. Did you even watch them?

Lastly, I am told that an anchor-properly-set-by-backing-down-that-hasn't-rotated and is now 180 degrees backwards to a reversing current is BETTER than a set-but-not backed-down anchor that is rotated and correctly aligned to the pull.

Oh, except forget to mention unless there is a really big wind or a storm? You know, when you need you anchor the most but you backed it down in the WRONG direction?

Then presumably you are screwed because Panope did say he observed a 180 degree pull-out failure but we won't mention that! So much for the whole backing down theory. You can't have it both ways.

Haha. Keep it coming!

We are basically in full agreement, but I'll add one further comment (hopefully, nobody will be offended). The only time we reset our anchor, is when a significant wind change is expected during the night or when we plan to be ashore. I'll make a point of resetting in the opposite direction of the expected oncoming wind, then let the boat drift back to its present location. In other words.... I set the anchor to the expected wind, not the present wind, then we're all set for the shift and there's no late night surprises. I don't pull up the anchor and begin again, I just gently reverse the boat in the opposite direction in order to rotate the anchor, then slowly up to 2000rpm (briefly) for the "set." My goal isn't to yank out the anchor.

Hopefully, nobody's overly-sensitive panties will wad up from such a radical suggestion.

[Panope]

Noelex,. I do both.

Momentum for the immediate feedback + long power set while taking transits.

Belt and suspenders

Steve

[Panope]

Originally Posted by Kenomac

We are basically in full agreement, but I'll add one further comment (hopefully, nobody will be offended). The only time we reset our anchor, is when a significant wind change is expected during the night or when we plan to be ashore. I'll make a point of resetting in the opposite direction of the expected oncoming wind, then let the boat drift back to its present location. In other words.... I set the anchor to the expected wind, not the present wind, then we're all set for the shift and there's no late night surprises. I don't pull up the anchor and begin again, I just gently reverse the boat in the opposite direction in order to rotate the anchor, then slowly up to 2000rpm (briefly) for the "set." My goal isn't to yank out the anchor.

Hopefully, nobody's overly-sensitive panties will wad up from such a radical suggestion.

I have done this. Seems like a reasonable tactic.

I have also been in a narrow channel where wind will ONLY happen one way or the other. Without a good forecast of upcoming wind direction, I'll set the anchor 90 degrees to the channel. That way, when/if the wind picks up, the anchor only has to rotate 90 degrees.

Steve

[Pelagic]

Originally Posted by Suijin

It amazes me that this topic has generated such strong (and borderline rude) declarations that backing down is not necessary. No one is making you do it. Keep doing what you want to do. But to categorically claim it's not necessary, to those of us who have genuine experience with it's benefits, is absurd.

I think that this happens when people assume we are arguing 'absolutes' rather than changing tactics for different conditions and forecasts.

When it becomes personal... the value of the discussion deteriorates!

[Delancey]

Because I know the anchor has rotated around and moved about through the bottom a bit, it has gotten me to question myself whether I need to back down the anchor again since it's essentially in a new spot and hasn't been backed down on.

Is that what you guys are saying? That I should be re-backing down on the anchor every time the anchor rotates around?

[Panope]

Originally Posted by Delancey

How many times does an anchor need to "re-set" until they set no more, assuming it continues to set as deep or deeper each time?

How can you guarantee this when you can never guarantee the bottom unless you back down each time?

I'm just asking.

If you are in a situation where the anchor is truly pivoting/re-seting with each tide change, I would either wake up and power set the anchor each time, or set up a Bahamian Moore (with a single rode + swivel), or move to a different Anchorage.

Steve

[conachair]

Originally Posted by Delancey

How many times does an anchor need to "re-set" until they set no more, assuming it continues to set as deep or deeper each time?

I've anchored in the same (fast, ~4/5Kt in springs) tidal spot for months before with the transits rock solid. Backing down first set just to check the holding and make sure the hook isn't wrapped up in a shopping trolley

Where I'm anchored now people stay put for ages, when a problem arises it seems more often to be from a huge number of twists in the chain as the boat usually seems to rotate one way.

[Delancey]

Originally Posted by Panope

If you are in a situation where the anchor is truly pivoting/re-seting with each tide change, I would either wake up and power set the anchor each time, or set up a Bahamian Moore (with a single rode + swivel), or move to a different Anchorage.

Steve

Ha. I never make any assumptions and always pay attention to what's going on around me ready to move if I need to. It's just lately I have noticed I haven't had to.