The safe working load for 1/2 three strand nylon is more like 1500 lbs. That's a serious mismatch with the chain's working load of 3900 lbs.
Another Anchoring Question
- Thread starter Bob S
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anchoring sore subject for me 
During Mardi Gras in Galveston we had a storm come in while I was enjoying the parade. I was an idiot and have posted a few idiot messages and now need to clear them up.
I've stated that the Bulwagga is an idiot proof :Liar: anchor but I was wrong. It can and will reset itself EXCEPT when there are big waves.
I came into the anchorage that had a lot of fetch (normally we only anchor there with south wind, not a north wind, but it was reported to only be 15 knots so I planned to anchor there) and 25 knots of wind with 8:1 scope on my 44 lb Bulwagga and 50' of 3/8 chain. The waves were only about 1.5' and the anchor was holding without being backed down, just like it always does.
Later while we were ashore, the wind shifted about 30-50 degrees and picked up 10-15 knots more and waves increased to 5' (according to those who were there). Seems the waves caused my boat yanked the anchor out, as I didn't back it down. We have about 2' of soft mud on top of hard mud there and that soft mud combined with the waves and heavy winds were too much for it to reset before the boat traveled 150 yards to a concrete wall.
I did not have a problem with the anchor during the first half of Ike in 100+ knots of wind, even with the waves, because the stern was not riding the waves so there was no upward pull. The second half, which I slept through most of it, seemed to have an effect on the anchor and I think during a good part of it I was just resting on the Fortress (rode on the Bulwagga was slack after the storm but tight on the Fortress). The difference was the bow was riding the waves and the anchor wasn't backed down due to the 180 degree wind shift.
So, the two lessions I had to learn the hardway is: 1) ALWAYS back down the anchor as good as you can so no wake or waves or anything else can rip out the anchor 2) ALWAYS deploy two anchors when leaving the boat as the weather man is not always right.
I still think the Bulwagga is a great anchor and will keep it as my primary but I have to be more careful about getting it set all the way and avoiding waves.
As for the other questions: Yes, you do not swing at anchor when anchored from the stern. Yes, you do get more slap when you do so because of that I do not recommend this as that slap is loud down below. For a mooring...don't have any comment as I don't know how it will ride.
During Mardi Gras in Galveston we had a storm come in while I was enjoying the parade. I was an idiot and have posted a few idiot messages and now need to clear them up.
I've stated that the Bulwagga is an idiot proof :Liar: anchor but I was wrong. It can and will reset itself EXCEPT when there are big waves.
I came into the anchorage that had a lot of fetch (normally we only anchor there with south wind, not a north wind, but it was reported to only be 15 knots so I planned to anchor there) and 25 knots of wind with 8:1 scope on my 44 lb Bulwagga and 50' of 3/8 chain. The waves were only about 1.5' and the anchor was holding without being backed down, just like it always does.
Later while we were ashore, the wind shifted about 30-50 degrees and picked up 10-15 knots more and waves increased to 5' (according to those who were there). Seems the waves caused my boat yanked the anchor out, as I didn't back it down. We have about 2' of soft mud on top of hard mud there and that soft mud combined with the waves and heavy winds were too much for it to reset before the boat traveled 150 yards to a concrete wall.
I did not have a problem with the anchor during the first half of Ike in 100+ knots of wind, even with the waves, because the stern was not riding the waves so there was no upward pull. The second half, which I slept through most of it, seemed to have an effect on the anchor and I think during a good part of it I was just resting on the Fortress (rode on the Bulwagga was slack after the storm but tight on the Fortress). The difference was the bow was riding the waves and the anchor wasn't backed down due to the 180 degree wind shift.
So, the two lessions I had to learn the hardway is: 1) ALWAYS back down the anchor as good as you can so no wake or waves or anything else can rip out the anchor 2) ALWAYS deploy two anchors when leaving the boat as the weather man is not always right.
I still think the Bulwagga is a great anchor and will keep it as my primary but I have to be more careful about getting it set all the way and avoiding waves.
As for the other questions: Yes, you do not swing at anchor when anchored from the stern. Yes, you do get more slap when you do so because of that I do not recommend this as that slap is loud down below. For a mooring...don't have any comment as I don't know how it will ride.
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I think tonight I'll search the archives and take all my idiot comments out about not having to set the Bulwagga. It does dig in deeper the harder you pull on it, but I guess 25 knots of wind isn't enough pull to get it deep enough to handle the waves.
Quote "1/2, 3 strand nylon line is rated for 7500 lbs yet 5/16 chain has a 3900 working load. Why would that be a mismatch?"quote
Mismatch is not really a problem here since the 1/2 line is a good size for your beamy C30. It is the 5/16 chain that is one size up from what you really need for normal conditions. If you are getting new line to go with the stronger Manson you might consider New England Rope's "Mega Plait", which is about 50 percent stronger than same-size 3-strand and stows more compactly. I know some will cry "3-strand only". Other wise, I'd say 9/16, since 5/8 is really bulky. My slip neighbor, JIMM, has the C30 and not all that much anchor locker room as I recall. West marine just this afternoon put out a good email on the whole anchoring scenario. Check their anchoring advisor and Chapman's has a little bit about it.
Mismatch is not really a problem here since the 1/2 line is a good size for your beamy C30. It is the 5/16 chain that is one size up from what you really need for normal conditions. If you are getting new line to go with the stronger Manson you might consider New England Rope's "Mega Plait", which is about 50 percent stronger than same-size 3-strand and stows more compactly. I know some will cry "3-strand only". Other wise, I'd say 9/16, since 5/8 is really bulky. My slip neighbor, JIMM, has the C30 and not all that much anchor locker room as I recall. West marine just this afternoon put out a good email on the whole anchoring scenario. Check their anchoring advisor and Chapman's has a little bit about it.
Franklin that sucks
That damage sucks! I am really, really, sorry to hear about your mishap. For years I have been ridiculed and poked at fun by some on this and other forums for recommending an 80% of WOT back down even with new generation anchors. The bottom line is unless you subject your hook the the most force and pull you physically can you have no way to know what happened on the bottom or if the anchor actually set. Just because it's calm when you set does not mean it will remain calm over night or even a few hours later..
Backing down on ANY anchor is very important..
Franklin,
That damage sucks! I am really, really, sorry to hear about your mishap. For years I have been ridiculed and poked at fun by some on this and other forums for recommending an 80% of WOT back down even with new generation anchors. The bottom line is unless you subject your hook the the most force and pull you physically can you have no way to know what happened on the bottom or if the anchor actually set. Just because it's calm when you set does not mean it will remain calm over night or even a few hours later..
Backing down on ANY anchor is very important..
actually, I've been experimenting...
...with Franklin's theory the past few months--only in instances where I've had plenty of room to drag--and I've found it to work so far (using a 25k Rocna with an all chain rode.) But I would never fail to set the anchor in the following circumstances: (1) when I'm planning to leave the boat for any reason, including a swim or a dive; (2) when I'm within a couple hundred meters of anything resembling stone; (3) when there's a fine bottle of wine between me and bedtime.
Of course, I'm usually anchoring in bay silt, so even a mushroom anchor will set itself nicely, given enough time.
...with Franklin's theory the past few months--only in instances where I've had plenty of room to drag--and I've found it to work so far (using a 25k Rocna with an all chain rode.) But I would never fail to set the anchor in the following circumstances: (1) when I'm planning to leave the boat for any reason, including a swim or a dive; (2) when I'm within a couple hundred meters of anything resembling stone; (3) when there's a fine bottle of wine between me and bedtime.
Of course, I'm usually anchoring in bay silt, so even a mushroom anchor will set itself nicely, given enough time.
Franklin, Sorry to hear and see the pictures of the boat.
Hope you get things back together soon!
r.w.landau
Hope you get things back together soon!
r.w.landau
Re: anchoring sore subject for me
That hurts just to look at it. No structrual damage I hope? The visual damage is bad enough. Do you suppose that the large wave action changed the real scope enough to cause the anchor to break out? On my boat if the wave period is just right the bow will move much farther than the wave height would suggest.
That hurts just to look at it. No structrual damage I hope? The visual damage is bad enough. Do you suppose that the large wave action changed the real scope enough to cause the anchor to break out? On my boat if the wave period is just right the bow will move much farther than the wave height would suggest.
Sorry to hear about it, Franklin
All the best from a lesson learned, thanks for sharing it, and best in getting repairs made asap.
Stu
PS -- maybe now they'll start believing...
All the best from a lesson learned, thanks for sharing it, and best in getting repairs made asap.
Stu
PS -- maybe now they'll start believing...
Yeah, there is a lot of structural damage. About 10 feet of the deck to hull joint lip was demolished. The foreward structural bulkhead busted. Judging from the lockers in the galley, it looks like the hull was flexing 2". Those waves were pounding it against the concrete.
I have thought a lot about it and believe it was the combination of the change in scope due to the waves and also the sudden jerkyness of the waves that yanked it out. It was set a little due to the 25 knots it was holding against before we left, but not enough to handle those waves.
I figure it's going to take them a month to fix and they can't get to it until May or June because of the backlog of hurricane damaged boats so I'm going to have to find something to do with my time for the next 5-6 months.
I have thought a lot about it and believe it was the combination of the change in scope due to the waves and also the sudden jerkyness of the waves that yanked it out. It was set a little due to the 25 knots it was holding against before we left, but not enough to handle those waves.
I figure it's going to take them a month to fix and they can't get to it until May or June because of the backlog of hurricane damaged boats so I'm going to have to find something to do with my time for the next 5-6 months.
Maybe it's time to build a sailing dink and play in the little pond.
The repairs can be done but the hassle and expense is a bitch. You will have to just about strip the interior clean of movable stuff and of course all of the valuables.
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