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Old 26-04-2012, 07:16   #16
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Re: Dragged the Rocna for the first time last night.

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Originally Posted by Dockhead View Post
Last few years I started to back down at full RPM for a few minutes to try to flush out any such situation.

At the same time, you burn the carbon out of the engine after low speed running.

My father and others think I'm crazy, but if the anchor is set, it will definitely hold up to full throttle in reverse. If it doesn't, it's not set -- that's all there is to it.

I had to reset my 55kg Rocna more than a few times when this technique revealed that it wasn't actually set.

I think what kind of anchor you have it really important, but of course you need a certain amount of technique, too.
I do this as well, but it's usefull to remember that the engine will at best provide a few hundred pounds of pull, whereas the anchor can see thousands in a blow, so again no guarantee, but it sounds like you already take this into account.
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Old 26-04-2012, 07:41   #17
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Re: Dragged the Rocna for the first time last night.

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Originally Posted by Dockhead View Post
Last few years I started to back down at full RPM for a few minutes to try to flush out any such situation. At the same time, you burn the carbon out of the engine after low speed running.

...

I think what kind of anchor you have it really important, but of course you need a certain amount of technique, too.
+2

We've always anchored like this. Find a good spot with a decent bottom and enough swing room. Drop slowly while into the wind. Feed rode out to 7:1 (or as much as possible), dig in slowly at first with wind or engine. Ramp up to full reverse throttle. Our anchor must hold at full throttle or we pull up and reset.

I'm constantly amazed at people who drop the hook with no attempt to dig it in properly (and sometimes just pile it all in one big heap underneath the bow). No anchor will hold in even a moderate blow without being dug in. Anchors don't hold on their weight, their mass is used to help dig them in.
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Old 26-04-2012, 08:05   #18
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Re: Dragged the Rocna for the first time last night.

plenty of weighty scope guys.............
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Old 26-04-2012, 08:28   #19
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Re: Dragged the Rocna for the first time last night.

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Last night our Rocna dragged for the first time in our 3 years of ownership.
This is a good baseline to have, noelex, especially if we can project a Rocna drag ratio of one per 1,000 nights on the hook.

I've got somewhere between 200 and 300 nights on my Rocna, and it has never yet dragged. It's easy to become complacent at that point. Indeed, if I've got plenty of room to drag, I tend not to set it as aggressively as you do, simply because the wind tends to do the work for me.

The more troubling part of your narrative, for me, is the point about anchoring in sand over rock. In conditions like that I'm inclined to get out the FX-55 and hope it works its magic.
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Old 26-04-2012, 08:38   #20
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Re: Dragged the Rocna for the first time last night.

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Yeah, I know what you mean! The CQR is, in that respect, the ideal "training anchor"!
Ain't that the truth..

I started with a CQR 35 lbs, after sitting too many anchor watches, got a Delta 55 lbs, had it for 9 years, then 4 years ago graduated with a Rocna 44 lbs.
(33 foot sailboat)

Dragged plenty with the CQR, once with the Delta and once with Rocna.

Sleeping good these days.
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Old 26-04-2012, 09:29   #21
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Re: Dragged the Rocna for the first time last night.

I use to see a boat in Santa Cruz that rigged a stern line to the anchor chain and set the hook in forward because it produced more thrust. All the above is good data and as stated, one drag in 1000 uses are great odds. Cost wise, I'm looking at the Manson Supreme, not seeing a lot of difference between the two. I have a Bruce now but want another primary anchor.
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Old 26-04-2012, 14:56   #22
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Re: Dragged the Rocna for the first time last night.

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I use to see a boat in Santa Cruz that rigged a stern line to the anchor chain and set the hook in forward because it produced more thrust.
I do this if it is really supposed to blow, it definitely works well. I also try veering back and forth some to really make sure the anchor is set. Just be careful that you don't let any line near the prop.
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Old 26-04-2012, 15:11   #23
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Re: Dragged the Rocna for the first time last night.

Some pretty good methods there. Has there been any discussion about reading the bottom conditions by observing the adjacent land. Streams and rivers create an underwater fan of newly deposited soil so anchors can dig deep. Eroding shorelines have had the seabed deepened, soil removed and often a hardpan base. Over a long period of time rivers and streams often meander from one side of a beach to the other so poor conditions can be at one end of the beach and good conditions at the other.
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Old 26-04-2012, 16:38   #24
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Re: Dragged the Rocna for the first time last night.

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Originally Posted by Dockhead View Post
+1



My father and others think I'm crazy, but if the anchor is set, it will definitely hold up to full throttle in reverse. If it doesn't, it's not set -- that's all there is to it.

I had to reset my 55kg Rocna more than a few times when this technique revealed that it wasn't actually set.

I think what kind of anchor you have it really important, but of course you need a certain amount of technique, too.
True. This is why it is hard to separate good anchor performance from crappy technique. Some anchor literature says "such and such enormous holding power at 5:1 scope!".

Irrelevant to me, as that's calm to light air "lunch" scope. I don't see that "more holding power" means "less scope" or "all rope rode" or other shortcuts. If I am in 15 feet, I put out about 105 feet, 15 feet of which is chain, for a 9,000 lb. boat It's part of the deal of anchoring...you do all that you can to create a catenary sufficient to keep that anchor from being shock-loaded, ideally at all.

I know the problems having a 200-odd foot "swing circle" can cause with one's neighbours, but to my mind, it's no excuse for shortening the rode in hopes that the Acme Miracle Anchor will somehow compensate.

In related thinking, airbags allow morons to drive faster without donating organs.

When you haven't budged after a wild night and all about you have, that's all the proof you need that you are doing it right. Physics isn't really interested in people's opinions.
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Old 26-04-2012, 16:41   #25
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Re: Dragged the Rocna for the first time last night.

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Originally Posted by klem View Post
I do this if it is really supposed to blow, it definitely works well. I also try veering back and forth some to really make sure the anchor is set. Just be careful that you don't let any line near the prop.
I would imagine a fairly monstrously sized bridle (along with seriously backed cleats or other attachment points on deck) would deal with this.

The good news is that such a bridle would be great for a Jordan Series Drogue!
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Old 26-04-2012, 17:02   #26
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Re: Dragged the Rocna for the first time last night.

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Originally Posted by S/V Alchemy View Post
True. This is why it is hard to separate good anchor performance from crappy technique. Some anchor literature says "such and such enormous holding power at 5:1 scope!".

Irrelevant to me, as that's calm to light air "lunch" scope. I don't see that "more holding power" means "less scope" or "all rope rode" or other shortcuts. If I am in 15 feet, I put out about 105 feet, 15 feet of which is chain, for a 9,000 lb. boat It's part of the deal of anchoring...you do all that you can to create a catenary sufficient to keep that anchor from being shock-loaded, ideally at all.

I know the problems having a 200-odd foot "swing circle" can cause with one's neighbours, but to my mind, it's no excuse for shortening the rode in hopes that the Acme Miracle Anchor will somehow compensate.

In related thinking, airbags allow morons to drive faster without donating organs.

When you haven't budged after a wild night and all about you have, that's all the proof you need that you are doing it right. Physics isn't really interested in people's opinions.
It's not that 5:1 is inadequate for most anchoring but that it is inadequate with your particular rode and no Acme Miracle Anchor.

Most cruising vessels with their standard oversize, new generation anchors and all chain rode will find 5:1 adequate in most conditions increasing scope as condition deteriate.

Not saying you cannot anchor with rope but with only 15ft chain and some anchors you would need all the scope you can get. As long as you don't drag and can sleep comfortably then all is well.
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