[Rhodes22-list] Anchoring -- Phuzzy Physics

Thu Jan 12 11:07:05 EST 2006

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" People do passionately believe that they must add weight to their metal anchors to make them sink, and that that is the reason for adding chain."

I don't know anyone that believes that. You may, and I would agree with you that their position is wrong. Everyone I've ever talked to about this, and everything I've ever read, talks about the weight of the chain changing the angle of pull, as well as acting as a buffer for the tension of the rode.

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"PS -- The "putting your life on the line" comments are also straw man attacks.  That's just silly stuff.  Many cruisers have all line rodes. I'll get to that later."

I couldn't disagree with you more. I qualified my statement by saying "someone new to sailing", as well as "may be". I stand by that. Of course it's silly if your correct, and an all rope rode is every bit as effective as chain, and there is no advantage with chain. I don't know whether that's true or not. However, if it's NOT true, and someone new to sailing follows your advice, anchors in mud, gets a poor set because they didn't use chain (again, this is predicated on the assumption that chain is needed for the set) and ends up on the rocks while they're asleep in the v-berth, then they would very much be placing their boat and their lives on the line.

Besides all that, it's NOT a "straw-man" attack, because I didn't mis-state your position and attack that.

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"please comment; your actual experiences are as valuable to me as I hope mine will be to you."

My actual experiences are so limited as to be almost useless. I've anchored my O'Day 25 4 or 5 times in the same lake, for no more than 3 hours at a time, with a combo chain/rope rode. Every time, the anchor set, and the boat held. I anchored one time over night on the same boat, same Danforth style anchor, in the ICW off the coast of Texas using the same set technique. The set held.

I crew on a race boat, and last July 4th, all the racers held a get together. Our skipper set the anchor with his all rope rode, and it didn't hold. He said he had done it before with no problem (but being honest, he's prideful enough that he wouldn't have admitted had it not been true), and he tried three times to set the anchor. It never properly set. I watched him, and I couldn't see anything he was doing differently than me. He attributed it to luck of the draw, stated that he must have hit rocky bottom each time :).  Same style anchor (though a little smaller, but also a smaller boat), same lake, different skipper, different rode, different results. Too many variables to come to any real conclusion.

The one time I took my Coronado 35 project boat out, I foolishly failed to check the anchor before I left. The diesel quit on me, and I went below and grabbed the anchor. There was no rode attached ( c'mon now, I admitted I did a foolish thing). I gathered every dock line I could find, and tied them together and tied it to the anchor. Set it the way I "normally" do (in my limited experience). Lake Pontchartrain is only about 15' deep in that area, but has a VERY muddy/silty bottom. The anchor set, but the boat was drifting. The Coronado has a VERY high freeboard area, so it's more easily affected by wind than my O'Day (and it's almost always a windy day on Lake Pontchartrain). The I-10 overpass was looking frighteningly close and getting closer. In spite of that, I was so afraid of drifting even faster if I pulled anchor, that I kept what I had, let it slowly slip, while my wife watched and I worked on the motor. I got the motor started before we hit the bridge, pulled anchor, and chewed myself out in front of my wife :). Different boat, different bottom conditions, but an all rope rode as opposed to chain/rope combo. Again, too many variables to come to any real conclusion.

That's my total anchoring experience. Not much to go on, but in my limited experience, and it IS VERY "limited", I've never come out of a chain/rope situation shaking and scared, half the time that I've had an all rope rode experience I was shook up, and the other half I was amused and irritated at the same time.

I don't think you're going to be successful at convincing me that I should give up the chain.

Herb Parsons

S/V O'Jure
1976 O'Day 25
Lake Grapevine, N TX

S/V Reve de Papa
1971 Coronado 35
Lake Pontchartrain, Louisiana Coast

>>> bill at effros.com 1/12/2006 10:24:09 am >>>
Herb,

I understand your point, and will respond to it in Dave's following 
memo.  I am not the one who raised the "straw man" argument regarding 
"helper metal" (although that term is mine, it does accurately reflect 
the thrust of the argument advanced by others.)  People do passionately 
believe that they must add weight to their metal anchors to make them 
sink, and that that is the reason for adding chain.

This anchoring thing is so tied up with myths passed along by people 
like you and me who have never anchored a whole lot, but who are good 
readers.  We pass along the comments of others--who may not have 
anchored a whole lot either.  I really did spend a lot of time in 
non-critical situations testing the theories that have been passed down 
to us.  If I put the whole analysis into a single lengthy email everyone 
would hit the delete button when they got to something they didn't agree 
with, and that would be the end of that.

Instead, I am going to break it down to individual points, and we can 
debate them based on what we have all read and experienced.  I will say 
over and over that my experience is limited to sand/clay/mud/muck 
bottoms which are probably what most of us (but not all) sail in.  I can 
anchor in rocks, but I don't know if it's the same as anchoring off the 
Maine coast.  I don't think anyone should anchor on coral.

More to come; please comment; your actual experiences are as valuable to 
me as I hope mine will be to you.

Bill Effros

PS -- The "putting your life on the line" comments are also straw man 
attacks.  That's just silly stuff.  Many cruisers have all line rodes.  
I'll get to that later.

Herb Parsons wrote:

>Bill,
>
>You're doing what I see a lot of people do when they try to argue a point that they believe passionately about - you're mis-stating your "opposition's" position, then attacking that position. It's called a straw-man attack.
>
>No one believes for a minute that an anchor needs "helper metal" to sink. However, there can be an argument made that Danforth style and Bruce style anchors are designed to be set by being pulled at a certain angle. Even by your own admission and description of how you use your anchoring system, an all rope rode would pull the anchor at a different angle than a chain rode would. Or at least, it would if the two systems were of equal length.
>
>Now, I don't anchor my boat often enough to really have much input on this one. Because I don't anchor my boat very often, I choose to go with the widely accepted practice of using chain for my system. You may very well be right in your assessment, but please don't obfuscate the debate by inserting nonsense like below. Keep in mind that if someone new to sailing believes what you're saying, and acts on it, they are then possibly putting their boat, and even their lives, on the line. That alone means the discussion is worthy of real discussion, not nonsense like "metal doesn't need help sinking, if you don't believe me try this experiment..."
>
>
>Herb Parsons
>
>S/V O'Jure
>1976 O'Day 25
>Lake Grapevine, N TX
>
>S/V Reve de Papa
>1971 Coronado 35
>Lake Pontchartrain, Louisiana Coast
>
>
>  
>
>>>>bill at effros.com 1/12/2006 8:40:27 am >>>
>>>>        
>>>>
>All metal anchors sink.  No metal anchor requires "helper metal" in the 
>form of chain to drag it down to the bottom.  Anyone who seriously 
>doubts this should try this little experiment:  Remove your anchor from 
>your chain rode, and throw the anchor overboard.  If it floats, be sure 
>to take a picture--there could be a Nobel Prize in your future.
>
>Bill Effros
>
>
>__________________________________________________
>Use Rhodes22-list at rhodes22.org, Help? www.rhodes22.org/list 
>
>  
>
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