Anchor comparison for Eric

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Marin

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Eric---- Took these two shots today for you. We are in another temporary slip until the replacement of our dock is complete. There is a CHB in the slip next to us. So in light of your recent comments on fluke to shank angle I took these photos. I flipped the shot of the Bruce so it would be pointing the same way as our anchor.

But it appears to me that the angle of the Rocna's fluke to its shank is significantly greater than the angle of the Bruce's center fluke to its shank. I draw no conclusions from this other than to say it seems to me that the greater angle of the Rocna fluke would make it dig in deeper than the Bruce when a pulling force is applied to the anchor given equal scope (which for us is 5:1 to 7:1.
 

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Take the bend out of the rocna shank and is it closer? A quick paper trace on my screen shows the result as pretty close but I can't see the actual rode attachment points...
 
psneeld, Marin,
Yes that is key I think. The angle of the dangles here should be measured from:
(a) The plane of the fluke to
(b) A line drawn between the center of the area of the fluke and the hole at the end of the shank where the rode attaches.
BUT:
The center of the fluke area on the Rocna is much easier to compute/conceive than the center of the Bruce area because of it's complex shape.
AND the the fluke of the Rocna is not flat or straight. But one can come fairly close fudging and judging for this and that. And part of this and that is greatly affected by the shank. The Rocna shank is much longer significantly due to the fact that the part of the shank that is closest to the fluke is raked outward. And that puts the fluke much further away from the rode attach point. The Claw's shank close to the fluke is raked the other way bringing the fluke closer to the rode attach point. This gives the Claw a steeper, wider angle. I think the rode attach point is closer than one would think in the picture on the Claw. From one anchor to another there is'nt a great deal of difference in this angle and it's always been given great importance to the performance of the Danforth. And several anchors make this angle adjustable. I think setting in mud can be easily done w fairly wide F/S angles but when the bottom gets more dense a narrower F/S angle works (sets) better. From everything I have read and heard (and only from what I have read and heard) the Claw is king of short scope anchoring performance. But for setting performance the Claw CHEATS. It uses additional flukes. And those flukes have a twist in them to help set the anchor while laying on it's side and to perform better for holding when the anchor is vertical or right side up. It's a clever design I think but I'm still in some doubt as to whether all three flukes ever get into the act. But if you're into anchor tests and especially what they say, several have said the short scope performance of the Rocna is rather poor, or at least not as good as it is at 7-1.
One test says:
"it was less impressive at 3:1 scope and under veering tests" .......
Rocna says/downplays this issue (in that same test) by saying one should set at 5:1 scope and shorten up but then one is still dependent on short scope performance while "shortened up". Mr Smith seems to forget about that. Most of the manufacturers are of the opinion that their product is flawless but the more I look at anchors the more I agree w FF. One should have an anchor for every occasion. If I was in a small cove in SE Alaska 75' deep w the shore close in and during a spring tide such that 2:1 would just barely keep me off the beach at low tide when it was to blow 40 knots ......I'd want the highest short scope performing anchorI could find. Any one of these variables may prompt me to want short scope performance.
BUT........much to most of this is centered around the anchor tests and they are almost all loaded with bias, much of it or even most of it unintentional. But that statement could be way off the mark too. Quite a number of things seem very well established like the extremely high holding power of the Fortress and for the Danforth types to bend more often than others.
But re the issue of this thread I think all anchors vary little in their fluke to shank angle and it probably does have an effect on short scope performance. It looks to me Marin that the Claw does have a wider angle. I think we've got a bit of an optical illusion in the pictures but the only way you could improve on the pics is to make the rode attach holes visible. Otherwise excellent photography for the occasion Marin .....and thanks.
 
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Eric--- FWIW way back when we were first considering the Rocna I called the company in New Zealand and talked to them at some length about their anchor, what size would be best for our boat, its performance, and so on. At one point I asked what they considered the best rode and scope for typical anchoring situations. They said all-chain and a 5:1 to 7:1 scope. The little instruction sheet that came with our anchor said the same thing. The subject of a short scope never came up and I didn't ask since I don't need to anchor on a short scope.

I think a short scope (by which I mean less than 5:1) is going to tax almost every anchor design if it gets pulled on by stronger winds because the angle of the rode when it's stretched out almost straight (combination rode) or has much of the catenary taken out (all-chain) is going to pull up on the shank and try to lever the anchor out. Whether it comes out will depend to a degree on its design but to a great degree on the bottom and how the anchor has set. We would never use less than a 5:1 on any anchor for that very reason--- the risk is too great in our minds should the wind come up.

In wandering around the yard yesterday evening taking a few shots I was surprised to see a number of the boats had rollbar anchors. While I've been seeing a scattering of rollbar anchors in our part of the marina over the years it was a surprise to see them on such a variety of boats now. Not all of the Rocnas were new (the difference is that the new ones have "Rocna" in raised letters on underside of the angled-up "flap" at the top of the fluke). There was even a huge one on a big aluminum Alaska limit seiner, something I thought I'd never see since these guys tend to stick with a stockless anchor like a Forfjord or an old car body.

And I got an e-mail out of the blue the other day from someone up here who must have corresponded with me a year or so ago--- I didn't remember him--- who was e-mailing several boaters he'd met asking us what anchor we used in the PNW. He just brought a boat up from California and it has what he feels is a way undersized CQR on it. I e-mailed him what anchor we had, and everybody else answered, too. I figured he'd get recommendations of Bruce, a bigger CQR, Delta, etc. Every one of the respondents, some of whom have pretty big boats with 100-plus pound anchors, had switched to a Rocna.

So the rollbar anchors are catching on in this neck of the woods.
 

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Marin,
Wednesday I'll be going to Craig for a number of reasons one of them being to patrol for Rocna's. I'll report if there are any there and give photographic evidence of such findings. The Rocna explosion must be exposed and I am going to be the exposer of large numbers of the Imperial Rocna's quietly manifesting themselves on the bows of small craft in the wilderness where such wonderful things were thought not to be present among the isolated folk of the far north where the essence of new and wonderful things as elements of the next generation mysteriously come to pass among folk and in a place where next generation things are rarely thought of much less coming boldly forth without preamble in the presence of all those that are at large among the small craft of the remote wilderness whereas each skipper of such craft has a responsibility to bring forth the elements of the new world in the next generation of things of monumental importance in the lives of those that cast their eyes upon upon the greatest brilliance of the new generation essence shining down from the bows thereof illuminating the privileged few that raise their eyes defiantly aloft to gaze upon the things of such beauty with the form following the function up from the stems of the bows so chosen to be the alter of offering to the wilderness people in their new found glory basking in the knowledge that the brilliance within and all about them be bestowed on every soul brave enough to go boldly forth and research the elements of anchor excellence to be applied to the illuminated lives of the few in this special place in the interest of being the king of the anchor mountain in Trawler Forum Land of the hookers of bottoms not yet discovered....... I'll look around...I'm hooked.
 
My experience along the inside passage and in SE Alaska is that anchorages 60 to 80 ft deep are common. Sometimes its impossible to find shallower anchorages.

In many 80 ft deep anchorages, using a 5 to 1 scope (400ft of rode) is and 7-1 (560ft of rode) exceeds my rode capacity. In many of those anchorages, there is not enough swinging room to deploy 560 ft of rode, or even 400 ft, even if you have it. Fortunately most anchorages of choice are somewhat protected so a lesser scope ratio can be used.

In the more boat-populated areas of the BC coast, sharing a 45ft deep anchorage with other boats precludes 7-1 (315ft of rode). Even getting the room for 5-1 (225 ft) is difficult.

In view of the above, an anchor that performs on short scope may be preferred over a higher power anchor that must use longer scope. If the Bruce is the choice, then going larger will help offset any perceived lack of holding power. On a 40ft 30,000lb trawler a 44lb Bruce may be too small, and should be replaced with a 66lb or larger.
Its easier for the boat to carry 22lbs more hook than to carry several more 100's of feet of chain.
 
Eric-- Be interesting to hear how many rollbar anchors you see. I would not confine your search for Rocnas alone but to Mansons, too, as they seem to be gaining in popularity in these parts as well.

Don't know that you'll see many of either though, up there. Pretty conservative crowd up in SE, particularly amongst the fishermen and local boaters in my observation. I don't know that they take kindly to new-fangled ideas, plus they are not inexpensive anchors.
 
Larry,
I think I've said that several times in the past. I wish others (more) would share their anchoring experiences and ideas. An anchor like a Sarca that Always seems to perform well under a wide varity of conditions is really the best choice. I changed my plans again for the trip south. Couldn't see spending significant money on yet another anchor so I paid a small fee and got a Claw twice as big. Traded the smaller one in. Put it on the bow earlier today and it actually fits. Looks good from the helm too in that it's hardly noticeable. Now I won't need to wrestle an anchor out of the hold if I don't use the Danforth. I'm not happy w the quality of the Claw though. I'm sending this on my I-pad.....practicing for the trip. I may bump into others up here in the northern waters too. Especially if they know where we are. I'll post at wi-fi places to announce my position along the way. I'm also hoping there'll be a TF gathering of Pudget Sound members in the fall. I should announce also that there will bea gathering of Willard boats (13 so far) in LaConner on mothers day weekend.. Wish I could be there.
Marin I see your post and if the weather's not terrible I,ll make the rounds. Got a doctor's apt and a dentist apt as well but I should have time. Won't forget my camera this time. I did expected some response from my silly post...Oh well.
 
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I did expected some response from my silly post...Oh well.

Eric--- I thought about it but I'm editing right now and looking at TF on my iPad while the edit computers are rendering effects and stuff. So I didn't want to take the time to comment on your extensive and impressive journey through the dictionary.
 
Eric,

What size claw did you get?
 
22 lb Larry. If I had known it was going to fit on the bow perhaps I should have gotten a 33 but 22 on my little Willy is the same as 44 on your bigger boats and should do. If the Claw works well on the trip south I'll be looking for a better one when we get south. I once thought Claws were all the same and the genuine Bruce talk was just "my stuff is better" or passed on talk from the manufacturer but at least I see subtle differences that aren't very subtle anymore. And then there's the Manson Ray that isn't even built the same way. Does anyone on the forum have one??? I don't even know who made the Claw I got. "22lb" is all it says on it cast into the shank. I really didn't think it was going to fit on the bow.
Marin, I had fun w the words and couldn't resist after I got going. Never done that before....one could go on forever. Think'in of more BS to sling got tiresome after a while. Your'e a man of many words and of course I wasn't trying to out-do you I was just trying to make a squeak.
 
Eric, by my reckoning, that lyrical post above contained just about the longest unpunctuated sentence on record. I think you are headed for the Guinness Book of Records for that one. What do you think, Marin..?

PS, Eric, for Gawds sake stop buying more anchors, because when you finally get a Sarca - and I think ultimately you will, it'll take years getting rid of all the others...
 
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OK Peter I did stop. I was about to get a bigger Manson or a bigger Claw but decided the four anchors I have on the boat should be enough.
Haha so you think a SARCAs in my future? They will need to get here first. But if they do my next anchor could well be a SARCA. Anchors are like cars and boats ...........never do think of getting rid of them. What a dark thought.
 
Eric, by my reckoning, that lyrical post above contained just about the longest unpunctuated sentence on record. I think you are headed for the Guinness Book of Records for that one. What do you think, .

After I'd graduated college and was working in commercial television I once wrote a letter (on a typewriter) to one of my best friends who was then--- and still is--- a professor in theatre at Virgina Tech. The letter was about three pages long, single spaced. I used no capital letters, no punctuation, and put no spaces between the words. sothewholeletterlookedlikethisanditwentonforthreepagesandheandhiswifespentseveralhoursfiguringoutwhatitsaid

My friend still has it.
 
No paragraph should be longer than five or six lines.
 
I would not have the patience to do that Marin. The grail goes to you.
 
It doesn't take patience, Eric. You just type. No caps, no spaces, no punctuation. It's a lot faster than doing it right.:)
 
Anchors in Alaska

I have been retired and living on a 50' Motor Sailor since 1983. I started out with a 65# CQR and found it to hold satisfactorily only twice. We put a 110# Bruce on and though it was far better than the CQR it too required sitting up all night during heavy weather. Looking around at the local fishing fleet we noticed all those that were well outfitted seemed to have a Forfjord anchor. We bought a #6 and it was up to almost all the
challenges put to it. We traded up to the #12 and have never had it drag in even full storm conditions. We have 600' of chain and normally
anchor in 75-100' depth water.
There are other lookalikes to the Forjord but they don't perform nearly as well. It also seems to hold in all bottom conditions locally found.
Buzzard
 
Interesting that. To my knowledge we have never had that type of anchor in Australia or NZ, but they look quite like a very heavy duty version of the Danforth type with which we are familiar, and not unlike the large ship type anchors. So, yes, I can easily believe they are good. Just not a very convenient shape for the boat designs and bow roller types of today.
Forfjord Anchors - Products
 
Anchors in Alaska

I can believe the anchors are not common in Alaska. They are built by a small foundry in the USA. They do not resemble any Danforth that I have ever seen but you may have a different Danforth down under than we commonly see in Alaska.
The Forjord currently resting on my bow roller is as securely and easily launched and retrieved as were the Danforths, CQR, Bruce and other common types that have been tried on it.
 
Buzz,
I'm not a fan of the Forfjord club. They seem to work fairly well and many to most fishermen almost worship them but I've never seen a small one on a boat. When I see a small one on a boat that has used it for years I'll take notice. My friend in Alaska that has a 30' Willard like mine has a 65lb Forfjord and is looking for a Dreadnought
I think one of the good features of the Forfjord is that in a wind direction change one fluke always stays engaged w the bottom so resetting isn't required but one might spend the night on only one fluke and it could be likely that most of the time only one fluke get's buried. With the Danforth that probably isn't possible.
Peter I think the Forfjord is definitely related to the Danforth. Take away the stock bar, make it much heavier and spread the the flukes apart quite a bit and you've got the basic Forfjord. Unlike the Danforth the Forfjord is very heavy for the amount of fluke area. If one is inclined toward heavy anchors bordering on the Navy types I think the Dreadnought is a better anchor but it's not easy to copy and they haven't made any for a long time. Actually I've never seen a Dreadnought copy and most are very rusty but re-galvanizing shouldn't be a problem.
 
After I'd graduated college and was working in commercial television I once wrote a letter (on a typewriter) to one of my best friends who was then--- and still is--- a professor in theatre at Virgina Tech. The letter was about three pages long, single spaced. I used no capital letters, no punctuation, and put no spaces between the words. sothewholeletterlookedlikethisanditwentonforthreepagesandheandhiswifespentseveralhoursfiguringoutwhatitsaid

My friend still has it.


Reading abbreviated or misspelled text is easy.

nfactitsntncssrytoinclallltrstomkitndrstndble
thhumnmindcnintrprtmostnythng
 
Buzz and Eric I should perhaps have qualified my 'Danforth type' statement a bit. I suspect you both knew this but to clarify...I call any anchor with two flukes joined and hinged horizontally at the end of the shank, and with angled flanges attached to the flukes where they are joined opposite the end of the shank, that deflect the flukes downwards, whichever side they end up lying on, Danforth types. Of course it could be argued the Danforth is just a modified dreadnaught or ships anchor - it they had a name I don't know it, but they all look rather variations on the dreadnaught theme anyway.
The issue there is they are vulnerable to skidding along the surface if the substrate is firm or weed-covered, and possibly a bit slow to reset with a large angle of pull change. However, on a vessel large enough to handle a heavy one - of any of these so-called Danforth/Dreadnaught/Forfjord/Fortress types - much of that is academic, I suspect.
 
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Oh yes Peter,
I forgot about the "pads" or "ramps" at the center of the anchor opposite the skinny end of the flukes that lift that end of the anchor that gives the flukes their angle of attack. Setting is probably fairly to mostly dependent on that as all these anchors (Dreadnought, Forfjord, Navy and Danforth) have that feature.
 
Several months ago, I took a walk around the marine and count the different anchors depending on the size/kind of the boat. The anchors reported to set fast/well have a sharp point and/or the edges narrow sharp, which may attribute to their setting. As you can see the 45+ ft commercial prefer the #8 or #12 Forjord, and start showing up on the pleasure.

The ramp and angle of the flukes, is a good point as the anchors that set fast also have a steeper angle so they dig in. I have seen some Forjords modified making the flukes wider/bigger, but have not taken note of the pads. Looks like I need to take another walk.

We only have a #6 or 65 lbs, would like to have a #12 or 145lbs. However, because of the windless and having all chain may have to settle on the #8 or 93 lbs.


Originally Posted by Phil Fill http://www.trawlerforum.com/forums/s42/k-dock-anchor-survey-6500.html#post92428
I took a walk down the Everett marine dock looking at what anchors boats have. This is the results:

Power 40 to 45 ft

Bruce 9

Danforth 3

Delta 1

Maxuim 3


Sail 40 to 45 ft

Bruce 2

QCR 4


Power 45+ ft.


Bruce 5

QCR 4

Danfoth 4

Forjord 2

Maxium 5

Ronoc 1


Sail 45+ ft

Bruce 2

QCR 7


On the commercial dock


Under 45 ft

Bruce 6

Danfoth 2

Forjord 2


Over 45 Ft

Forjord 7

Bruce 2



I took a walk 10+ years ago so we have three anchors – QCR, Danforth and a Forjord. The QCR was the primary anchor when we bought the boat. However, I found the QCR dragged, so I changed to the Danforth. Being I moored and tend to follow the commercial boat, I bought a Forjord which is the now the primary.


We have the chain/line/windless to deploy two anchors in need be. Many boats over 50 had to anchors a CQR/Bruce and Danforth/Forjord. I believed the anchor is dependant on the kind of bottom. Rock/Hard – Bruce/QCR mud/sand/soft – Danforth/Forjord.

 
Phil Fill, Good post. I have found that your choices are similar to mine.
I have never had any trust in the CQR after my negative experience for some
three years using it here in AK. To a lesser degree the same applies to the Danforth.
I use a 110# Bruce for stern anchor and an (approximately) 140 # Forfjord (#12) on the Bow. 600 feet chain in the bow and 400 in the stern, Never a problem. Buzzard
 
600 feet chain in the bow and 400 in the stern, Never a problem. Buzzard

I would guess not. Most of the time you could just lay out the chain and not need the anchor.:)
 
JD, RAMBLER, It seems apparent you haven't lived on anchor during the winter in SE Alaska. Winds are commonly 40-45 knots and at least 3 to 4 times a year rise to storm force. We have spent nights at anchor when the winds were exceeding 100 knots and we didn't feel that we had too much rode or anchor. These bays are often quite large and the waves can be counted on to cause pitching and rolling sufficient to telegraph significant motion to all your ground gear. Chain alone? I think not. Buzzard
 
Reading abbreviated or misspelled text is easy.

nfactitsntncssrytoinclallltrstomkitndrstndble
thhumnmindcnintrprtmostnythng

Gee, that was easy! In fact its not necessary to include all letters to make it understandable the humman mind can interpret most anything. :D

On PMM years ago they use to give me such a hard time about my spelling as I spell the way it sounds. That is how I got the name Phil Fill as they both sound the same. As you can see when I use the note pad without spell check its harder to read, but it seems most can muddle through! :hide:

So what were we discussing something about boats and big heavy metal things? :confused:

Not many boats can carry that much chain. Do you have a picture of your motor sailor? You anchor out year around?

We have 200 ft with another 200 ft of rope. Looking at the water line we could carry maybe another 100 or 200 ft. Next time we pull I am having several above water thru hulls move up 3 to 6 inches, along with the boot strip as we continue adding weight. :facepalm:
 

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