Reply
 
Thread Tools Search this Thread Display Modes
 
Old 06-25-2018, 03:43 PM   #1
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Country: USA
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 14,848
Anchor Depth/performance Reversals

There was a thread whereas a member had a rode reversal experience w a Manson Supreme and after the reversal the Supreme didn’t re-set.

Been thinking about that and have come up w a good possible reason it happened. The Supreme has an almost bullit proof rep so I did some wondering.

I haven’t used my Supreme much especially in the un-modified state but in tests across the board it’s been a very near top performer. But anchor tests mostly test holding power.

I thought about the many times people on TF have complained about lots of mud and weed on the anchors upon retrieval. I almost never have any mud and no weed at all. That’s been floating about in my mind for a few years and now I have thought of a good reason for the weed. It’s related to depth, water clarity and sunlight.

Steve G’s Anchor Setting Vids (ASV’s) were carried out anchoring in 25-30’ of water. I suddenly occured to me that I rarely set an anchor that shallow. With 18+ foot tides in Alaska the above is nearly impossible. So most of my anchoring has been at 35-40’ and often deeper. Saw many pics of “salad” on Steve’s anchors during the ASV’s that I’m thinking where reversals are likely one should anchor deeper to avoid most of the weedy bottoms that have a tendency to render good anchors worthless especially on reversals.

Also remember that when Steve drilled the holes in the Supreme’s fluke the problem evaporated. He said he just couldn’t make the holed Supreme fail. Back and forth many times he went. Well other manufactures can’t drill the holes we but we boat owners can. Soon I’ll try my little 12lb modified Supreme and if I get the chance before we head north to QC Strait I’ll try a few shallow sets and some deeper sets in the same area that Steve used and report.
__________________
Advertisement

__________________
Eric

North Western Washington State USA
Nomad Willy is online now   Reply With Quote
Old 06-26-2018, 10:29 AM   #2
TF Site Team
 
City: Westerly, RI
Country: USA
Vessel Name: N/A
Vessel Model: 1999 Mainship 350 Trawler
Join Date: Jan 2014
Posts: 1,170
There are two camps I find in most posts. Those who actively set their anchor, and those that let momentum, wind and current set the anchor. Personally, I back down on the anchor until it's set, then rev up to 1,000 rpm to ensure it's buried.

I would be curious the method employed by the person who dragged after a reversal. I would venture a guess that those who use momentum might not actually be setting their anchor. When a reversal occurs, there is a higher chance of the anchor not properly setting.

I've reversed and sat in 35 kt winds 180 degress from the direction of set with no issues. When I dove on the anchor, it was so well buried, the anchor didn't even reverse direction. In other words, I was pulling backward on the anchor in 35 kt winds.

Sometimes I have a difficult time breaking the anchor free at 0 scope.
__________________

Shrew is offline   Reply With Quote
Old 06-26-2018, 12:04 PM   #3
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Country: USA
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 14,848
Shrew,
As far as I know that’s the first time that’s been mentioned on TF. I’ve thought of it. Steve G did many reversals in a seafloor
not terribly compacted and don’t recall backwards anchor holding his boat. But most of the time we anchor in benign conditions and probably much of the time we’ve remained anchored wan anchor set bassawkwards.

Interesting thoughts and I’m glad you mentioned it. Has something to do w my next anchor post and for a moment I thought you were posting in the wrong thread. HaHa
Much of the time though re your post, anchors rotate w the shank mostly above the seafloor and the fluke buried. Frequently 180 degrees of even more. Even Danforths can do that depending on the bottom. Seen it also in Practical Sailor Anchor Tests. It’s common (I believe) but we usually have no idea if the anchor broke out and re-set or what as we can only guess what is truly going on down there.

It’s been a very long time for me to experience dificulty weighing anchor. But frequently I tie off and loosen up the anchor. But difficulty .. no. I do worry about snagging a cable ect and loosing gear. Never happened to me though even in the much logged PNW.

But my thread here was directed twoards anchoring deep (a bit) to evade getting one’s anchor fowled and rendered useless w weed. My thinking was just by just going a little this way or that may get our anchor deep enough to avoid most of the things that grow on the seafloor. Just a little feather in one’s cap that may save the day for those often anchoring shallow bottoms where reversing winds and current prevail.
__________________
Eric

North Western Washington State USA
Nomad Willy is online now   Reply With Quote
Old 06-26-2018, 07:21 PM   #4
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in Crisfield, MD
Country: USA
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 6,084
Let me start out by saying, I have a Rocna.

With the exception of test simulations at 4 knots with short scope, Rocnas and probably most modern anchor designs, pivot in place or only move a short distance before resetting. The reality of the situation is that in all but the rarest of circumstances, anchor reversals don't happen at 4 knots, usually less than 1 knot. Secondly, if you use proper scope, 7:1 ( haven't seen an anchor manufacturer endorse less), the anchor will have the ideal penetration angle to reset. Now there may be some places in the PNW where they anchor in 100'+ of water and 7:1 isn't practical, but most everywhere else it's doable.

IMO, most anchoring failures could have been prevented with 7:1 scope. Really don't understand why people feel the need to short scope. Hi, my name is Ted, I anchor with 7:1 scope, and sleep very well when on the hook.

Ted
__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is offline   Reply With Quote
Old 06-26-2018, 07:27 PM   #5
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 18,002
I have had no dragging issues with multiple reversals and wind shearing up to 35 knots also on my Manson Supreme 60 pounder....all 5/16 chain.

Usually on 5 to 1 scope unless staying multiple days or higher winds/currents.

If expecting wind over 20 knors or currents in excess of 2 knots I back down too, if less than that....I dont worry and just let it set itself.
psneeld is online now   Reply With Quote
Old 06-26-2018, 07:51 PM   #6
DDW
Senior Member
 
City: San Francisco
Country: USA
Join Date: Apr 2018
Posts: 400
Quote:
Originally Posted by O C Diver View Post
Now there may be some places in the PNW where they anchor in 100'+ of water and 7:1 isn't practical, but most everywhere else it's doable.
There are plenty of places in the PNW where you are anchored in 30', but 7:1 isn't practical as you will use the whole anchorage and there are 10 other boats in there. 7:1 in 30' depth takes about an acre of real estate.
DDW is offline   Reply With Quote
Old 06-26-2018, 08:08 PM   #7
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in Crisfield, MD
Country: USA
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 6,084
Quote:
Originally Posted by DDW View Post
There are plenty of places in the PNW where you are anchored in 30', but 7:1 isn't practical as you will use the whole anchorage and there are 10 other boats in there. 7:1 in 30' depth takes about an acre of real estate.
7:1 in 30' of water takes about a 300' radius from the anchor. Don't really want anyone closer than 300'. All kidding aside, I'm not anchoring with 10 other boats on 4:1 scope. It just seems a recipe for disaster.


Ted
__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is offline   Reply With Quote
Old 06-26-2018, 08:29 PM   #8
Guru
 
caltexflanc's Avatar
 
City: North Carolina for now
Country: USA
Vessel Name: Small Incentive
Vessel Model: Boston Whaler 130 Sport
Join Date: Aug 2011
Posts: 4,620
I'll post this for the umpteenth time. You will learn a lot about real world anchor behavior by observing your boat's movement directly, and mapping it on your plotter to inform that observation.

In this example, 25 ft water, mud bottom chain rode at a little over 3/1 scope, Delta anchor. Multiple days at same spot. Note how the boat pretty much lays to the chain when being pushed around by the tidal current clocking.Then a brief squall and comes out full length. Squall passes and back to normal. When weighed, about 20-30 ft of chain encased in mud, anchor encased shank and all.

__________________
George

"There's the Right Way, the Wrong Way, and what some guy says he's gotten away with"
caltexflanc is offline   Reply With Quote
Old 06-26-2018, 08:57 PM   #9
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Country: USA
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 14,848
Ted wrote;
“Secondly, if you use proper scope, 7:1 ( haven't seen an anchor manufacturer endorse less),”

Ted,
And what are anchor manufacturer’s motivation for getting it right? Sales and staying out of financial trouble. They don’t want to make any recomendations that there’s even a slight posibility of them proving wrong and their recomendations showing up in court. I know my anchors perform well at 3-1 and 4 or 5-1 for storms. But if I was selling anchors I recomend 7-1 too.

And why did you start out telling us you use a Rocna? This thread tried to have nothing to do with brands.
__________________
Eric

North Western Washington State USA
Nomad Willy is online now   Reply With Quote
Old 06-26-2018, 09:38 PM   #10
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in Crisfield, MD
Country: USA
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 6,084
Quote:
Originally Posted by Nomad Willy View Post
Ted wrote;
“Secondly, if you use proper scope, 7:1 ( haven't seen an anchor manufacturer endorse less),”

Ted,
And what are anchor manufacturer’s motivation for getting it right? Sales and staying out of financial trouble. They don’t want to make any recomendations that there’s even a slight posibility of them proving wrong and their recomendations showing up in court. I know my anchors perform well at 3-1 and 4 or 5-1 for storms. But if I was selling anchors I recomend 7-1 too.

And why did you start out telling us you use a Rocna? This thread tried to have nothing to do with brands.
Eric,
Have you ever read Chapman's?

https://www.amazon.com/Chapman-Pilot.../dp/0688148921

Pretty much the bible of small boat seamanship for generations. 7:1 scope has been the standard until you get into storm conditions. I agree with you, If you're an anchor manufacturer, why would you want to say anything about the required amount of scope and then find yourself in court defending it when somebody breaks lose putting their boat on the rocks.

The part I've never understood was why use less than the standard if you have the swing room? Why would you live on the edge at 3:1? It's certainly not safer. Or is this about bragging rights?

I mentioned Rocna and the other modern design anchors as the market seems to have embraced them in spite of their premium price and they as a group generally fair much better in reversals.

Ted
__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is offline   Reply With Quote
Old 06-26-2018, 09:55 PM   #11
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Country: USA
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 14,848
HaHa Ted you’re right about modern anchors but I’d never admit that to Marin Fare. He and his Rocna were a religious affair.

In SE Alaska’s little rock lined pocket anchorages 3-1 and even 2-1 is the norm. Many say they don’t anchor at 3-1 but I think they do. Almost always I don’t use 2-1 when I have more room. But after years of short scope anchoring one tends to belive in it. Look at Steve’s vids but as he says use longer scope for winds. Personally I rarely go above 5-1. Did a 50 knot gale at 5-1. That was my storm anchor though. But “living on the edge”? I’ll decide where the edge is. I do like Chapman and often quote their chain requirements.
__________________
Eric

North Western Washington State USA
Nomad Willy is online now   Reply With Quote
Old 06-26-2018, 09:55 PM   #12
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in Crisfield, MD
Country: USA
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 6,084
Quote:
Originally Posted by caltexflanc View Post
I'll post this for the umpteenth time. You will learn a lot about real world anchor behavior by observing your boat's movement directly, and mapping it on your plotter to inform that observation.

In this example, 25 ft water, mud bottom chain rode at a little over 3/1 scope, Delta anchor. Multiple days at same spot. Note how the boat pretty much lays to the chain when being pushed around by the tidal current clocking.Then a brief squall and comes out full length. Squall passes and back to normal. When weighed, about 20-30 ft of chain encased in mud, anchor encased shank and all.
Quite the dare devil you are. Glad you got away with it. What I've never understood is the resistance to putting down another 100' of chain and going from 3:1 to 7:1. Would pulling up and cleaning that extra hundred feet take more than 5 to 10 minutes?

Ted
__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is offline   Reply With Quote
Old 06-27-2018, 12:02 AM   #13
Guru
 
Ken E.'s Avatar
 
City: Bellingham WA
Country: United States
Vessel Name: Hatt Trick
Vessel Model: 45' Hatteras Convertible
Join Date: Nov 2016
Posts: 551
I'm with Eric. It's rare that I use more than 3:1, only in blustery conditions. 3/8" all chain rode, 66 lb claw. This has been my MO for many years in Alaska and PNW and it has worked well.
Ken E. is offline   Reply With Quote
Old 06-27-2018, 06:26 AM   #14
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 17,921
We mostly set a Bahamas more , second anchor astern lead to the bow.

Never a problem in a wind shift , the boat does not require acres to anchor , and only a 5 min exercise to perform.

Works well in tidal areas or reversing rivers too.
FF is online now   Reply With Quote
Old 06-27-2018, 08:10 AM   #15
Guru
 
jleonard's Avatar
 
Join Date: Jun 2008
Posts: 3,061
8 to 10:1 for me most of the time. All chain 35 Danforth in mud bottoms here in eastern LI Sound.
I let the drift initially set then I back down at 1000 rpm or so. I often have difficulty weighing anchor and a lot of mud to clean off the chain and I like it that way.
jleonard is offline   Reply With Quote
Old 06-27-2018, 03:13 PM   #16
Guru
 
caltexflanc's Avatar
 
City: North Carolina for now
Country: USA
Vessel Name: Small Incentive
Vessel Model: Boston Whaler 130 Sport
Join Date: Aug 2011
Posts: 4,620
Quote:
Originally Posted by O C Diver View Post
Quite the dare devil you are. Glad you got away with it. What I've never understood is the resistance to putting down another 100' of chain and going from 3:1 to 7:1. Would pulling up and cleaning that extra hundred feet take more than 5 to 10 minutes?

Ted
Because that worked dozens of times in that sort of bottom and in much worse conditions. In sketchy places you bet I'm deploying all I can.
And it takes a heck of a lot longer to retrieve and wash than 5 minutes.
caltexflanc is offline   Reply With Quote
Old 06-27-2018, 03:45 PM   #17
DDW
Senior Member
 
City: San Francisco
Country: USA
Join Date: Apr 2018
Posts: 400
Quote:
Originally Posted by O C Diver View Post
Quite the dare devil you are. Glad you got away with it. What I've never understood is the resistance to putting down another 100' of chain and going from 3:1 to 7:1. Would pulling up and cleaning that extra hundred feet take more than 5 to 10 minutes?

Ted
That won't make you very popular in many anchorages. I see you are in Florida where the water isn't very thick. Elsewhere is different.

I'll admit that the chain in the locker isn't going to do you any good - but may not do harm either. There is some science in this after all. Once the rode is pulling horizontally at peak load (that being the load that causes the anchor to move, or boat to stay) then additional scope does no good at all. The scope required to achieve this (on an all chain rode) is 7:1 only at shallow depths for typical holding. In very deep water it can be 2:1. Modern anchors actually hold pretty well on shorter scope than the horizontal criteria.

Now if you are laying to an old style anchor and/or on nylon, then a lot of scope might help. Still won't make you popular though. 7:1 in 30 feet means you are swinging a 570 ft circle on a 40' boat. That can be the whole anchorage in a lot of places, nearly two football fields. (30' depth + 5' up to bow roller * 7 = 245' + 40 feet of boat * 2).

I've gotten away with 5:1 and less in probably 500 attempts all around the continent. All chain on a Spade. I've also anchored in 100'. Didn't have 700' of chain. Sure if I'm anchored in 12', 7:1 doesn't like too much chain.
DDW is offline   Reply With Quote
Old 06-27-2018, 04:10 PM   #18
Guru
 
dhays's Avatar
 
City: Gig Harbor
Country: United States
Vessel Name: Kinship
Vessel Model: North Pacific 43
Join Date: May 2015
Posts: 7,152
Anchor Depth/performance Reversals

I usually try to put out 5:1. However, I often find that I get funny looks from folks that are perfectly happy and secure at 3:1.

If I am anchoring in 30’ of water and am expecting a 10’ tide increase and my bow roller is 5’ above the water. I prefer to lay out 225’ of chain. However, if I am in a small anchorage with a bunch of boats that have 100’ of chain out, it won’t be pretty.

Some of us anchor in anchorages where there are a number of other boats, in a small cove where we don’t have much swing room between rocks, or anchor in deeper water. I’ve used all 300’ of chain a few times and barely had 3:1 scope.

A lot easier to get 7:1 scope if you are anchoring in 7’ of water, little tide, and a 5’ freeboard. Particularly if you are fortunate enough to be able to be all by yourself.

Edit: Looks like DDW already made my point a few minutes earlier.
__________________
Regards,

Dave
SPOT page
dhays is offline   Reply With Quote
Old 06-27-2018, 05:23 PM   #19
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Country: USA
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 14,848
OK so none have any opinions or experience w how seaweed/salad effects the performance of anchors on reversals?
My notion of anchoring a bit deeper to avoid weed isn’t valid?
__________________
Eric

North Western Washington State USA
Nomad Willy is online now   Reply With Quote
Old 06-27-2018, 06:17 PM   #20
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in Crisfield, MD
Country: USA
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 6,084
Quote:
Originally Posted by DDW View Post
That won't make you very popular in many anchorages. I see you are in Florida where the water isn't very thick. Elsewhere is different.

I'll admit that the chain in the locker isn't going to do you any good - but may not do harm either. There is some science in this after all. Once the rode is pulling horizontally at peak load (that being the load that causes the anchor to move, or boat to stay) then additional scope does no good at all. The scope required to achieve this (on an all chain rode) is 7:1 only at shallow depths for typical holding. In very deep water it can be 2:1. Modern anchors actually hold pretty well on shorter scope than the horizontal criteria.

Now if you are laying to an old style anchor and/or on nylon, then a lot of scope might help. Still won't make you popular though. 7:1 in 30 feet means you are swinging a 570 ft circle on a 40' boat. That can be the whole anchorage in a lot of places, nearly two football fields. (30' depth + 5' up to bow roller * 7 = 245' + 40 feet of boat * 2).

I've gotten away with 5:1 and less in probably 500 attempts all around the continent. All chain on a Spade. I've also anchored in 100'. Didn't have 700' of chain. Sure if I'm anchored in 12', 7:1 doesn't like too much chain.
Never worried about being popular. Mom would tie a pork chop bone around my neck so that the dog would play with me. Nowadays I just keep beer and pork tenderloins in the fridge.

While I do live in FL and MD, cruising bank and forth on the AICW, I also did the Great Loop last year. So I've seen anchoring depths to 40'. Not going to claim any experience anchoring in 100' and maybe 3:1 is all that's required. However, anchoring in 7' of water with 21' of chain is just plain foolish.

Probably 95% of my anchoring is in 10' or less. 7:1 has never disappointed me. I don't infringe on other anchored boats and expect the same out of those arriving after me. 7:1 in 20' gives me a 120' radius including the boat. 120' separation makes for good neighbors. I've probably seen 8 or 10 boats that broke free or failed the reversal either in tidal currents or a squall. Bet they were all confident in their short scoping, except for that one time.

Ted
__________________

__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 06:15 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012