Anchoring again

[Nomad Willy]

Gerg,
More than brand of anchor this probably is a sea bed problem.
The most variable and troublesome aspect of anchoring.

The CQR’s problem is mostly setting IMO. Most all anchors work quite well holding but several (or more) don’t set well. Watching Steve’s vids I’m mostly impressed w the Super Sarca. But every anchor has a favorite sea floor to work with and an anchor that dosn’t need a lot of chain or-and scope is a blessing because all the chain you don’t need can be factored into anchor weight.

However I’m not very sold on bigger is better. One should think about “how much better”. Anchor design is clearly most important. And if you keep adding to the anchor weight factor or chain weight or even scope as one increases the value of the variable there comes a point where more chain, scope, anchor weight or size delivers little (and eventually nothing) to performance.

 

[Andy G]

Peter B;Just go with an appropriately sized (?+1) Sarca Excel, and you'll have no worries virtually ever. A Fortress as back-up for very soft mud might also be good, but you'll never get to use it.
PS I have no shares in Sarca, just know they are good.

Peter's love of all things Sarca is well known, though for good reason.

I traded our Rocna (25kg) for an Excell after an unsettling experience.

I anchored and went off in search of a coffee and came back to find the wind had shifted about 90 degrees and the boat was about one hundred meters from where I had left it, luckily still in the middle of the chanel.

I never felt entirely confident with the Rocna after that.

 

[Hobbit]

We use a Forfjord 18 anchor its 260 lbs with 60' of 1/2" chain and 1/2" galvanized steel cable rode. Our boat is not quite as big 57' and 92,000 lbs. Only had trouble once in 30 kts of wind in muddy bottom...just had to let out more line and that remedied itself. Rarely do we anchor with more than 2.5 : 1 of scope with no issues. I have a friend with a 65' boat 120,000 lbs with the same anchor and no issues in over 50 years.

 

[Mischief Managed]

You probably do not need another opinion, but on my 30,000ish lb, 44 footer, I replaced the 65 lb CQR, that came with the boat, with a 73lb Rocna Vulcan 33 and a Fortress FX37 after one season of use in New England. We anchor a lot and could not be happier with the Vulcan after 4 seasons in New England coastal waters. Have yet to try the Fortress since the Vulcan has been so reliable.

 

[Moonfish]

Just watched this video about the Ultra Anchor. Long video review, but thorough. We had an Ultra on a 45' charter catamaran in Tahiti a few years ago, and it worked as good as it looked. If you or anyone on TF wants one, PM me as we are online retailers for Ultramarine West products. They aren't cheap, but we can help out.

 

[cafesport]

The third most important thing in successful anchoring is the anchor, but it happened to be first thing we changed on our boat 11 years ago. Ditched a 350 lb plow for a 220 lb rocna. We have now spent well over 2500 nights on it and it apparently shows according to a broker or two. If we were to do it again now it would be a same size rocna but the new rocna2.

 

[tozz]

We use a Forfjord 18 anchor its 260 lbs with 60' of 1/2" chain and 1/2" galvanized steel cable rode. Our boat is not quite as big 57' and 92,000 lbs. Only had trouble once in 30 kts of wind in muddy bottom...just had to let out more line and that remedied itself. Rarely do we anchor with more than 2.5 : 1 of scope with no issues. I have a friend with a 65' boat 120,000 lbs with the same anchor and no issues in over 50 years.

We also use a Forfjord with 3/8" G4 chain in the PNW. Our bow configuration limits the anchor types we can carry. Our 65' boat came with a #12 and we upgraded to the #18 which their site lists as 210 lbs. We did drag a couple times in storms with the #12 (150 lbs) but both times scope was under 5:1 due to crowded anchorage conditions. Since upgrading we've been in 25+ kt three times with no problems. Once in an anchorage with a reputation for dragging due to eel grass but we stayed put with about 4.5:1 scope.

-tozz

 

[Juliet 15]

FWIW, I run a 58' boat at 110,000 lbs. I have a 121 lb Vulcan. I've not experienced anything above 40kts yet while anchored, but it's never dragged. I love this anchor.

 

[J.T kearney]

Hi All
I'm ready to up grade my old knock off 20 kg Bruce anchor for a vulcan but would like to go up a size (25 kg) but the recommended chain size goes up from 5/16 to 3/8. I had bought a new maxwell windless to accommodate my new 5/16 chain. My boat is a mainship 350 at (35 ft at waterline, 39 ft overall at 12 tons). Is there an issue using the lighter chain?
Cheers J.T.

 

[rslifkin]

Hi All
I'm ready to up grade my old knock off 20 kg Bruce anchor for a vulcan but would like to go up a size (25 kg) but the recommended chain size goes up from 5/16 to 3/8. I had bought a new maxwell windless to accommodate my new 5/16 chain. My boat is a mainship 350 at (35 ft at waterline, 39 ft overall at 12 tons). Is there an issue using the lighter chain?
Cheers J.T.

Use the lighter chain. Personally, I think manufacturers recommending chain size based on anchor size is stupid. Chain size is based on the boat and how much load it can put on the anchor. For a Mainship 350 I'd have no concerns about using 5/16" HT or G43 chain. 5/16" BBB may be a little on the weak side, but if that's what you have, most of the modern Maxwell windlasses use the same gypsy for 5/16 BBB" and 5/16" G43, so the windlass will work fine.

 

[Mac2]

s/v Panope's anchor testing is the best I've seen. Not only do you get to see the video results, but he tests the resetting ability of the anchor. Most tests I have seen only test the pull/holding strength. Another consideration, which few anchors advertise, is the shaft strength.
I'm 65 feet 90 ton. 500 feet 1/2 inch chain. I went with the 260 lb Sarca Excel. My second choice would have been a Spade anchor. I went with the Sarca because the construction impressed me. Shaft material, stainless tip, and steel ballast/weight instead of lead, so you can re-galvanize the anchor without having to melt out the lead. Plus all the fittings are welds, not bolts.
I have no affiliation with Sarca.

 

[J.T kearney]

RSLifkin
Thats what I was hoping to here. I've got 100 ft of 5/16 G4 and 150 ft of 5/8 rode. I was originally thinking of adding another 100 ft of G4 and keeping the same size anchor (20 kg) but in an old thread someone mentioned just to go with a larger anchor (25 kg) instead. A better return in holding power with a larger anchor verses more chain. It is surprising going from a 20 kg Vulcan to a 25 kg is almost twice the price.
Thanks for your input
Cheers J.T.

 

[sealandsky]

Before you buy - Check out "Ultra Anchor".

 

[bowball]

Before you buy - Check out "Ultra Anchor".

I have a 45kg Ultra on a 60' 70,000 lb boat, and have had no issues or regrets, though I have only experienced up to 40kt winds and anchor typically in 30 to 50' water with a scope of 5:1 usually. It is of course always easy to talk up size, and sometimes I wonder whether 55kg would have been even better, but then again why not 65kg! The equivalence of the creeping 2' size issue, without an obvious negative if it fits I suppose.

 

[Moonfish]

It is of course always easy to talk up size, and sometimes I wonder whether 55kg would have been even better, but then again why not 65kg! The equivalence of the creeping 2' size issue, without an obvious negative if it fits I suppose.

Good one! I don't think any trawler owner has ever said, "I wish I had a lighter anchor..."

 

[hmason]

Good one! I don't think any trawler owner has ever said, "I wish I had a lighter anchor..."

Well I did when my windlass failed.

 

[Moonfish]

Well I did when my windlass failed.

Ha! Good point.

My hydraulic drum windlass broke while bringing up the anchor in the Copeland Islands north of Lund, BC. We spent the night with about 150' out. Chain and anchor weigh over 300 pounds. Windlass broke with the anchor about 6' from the surface. Fortunately I had 6'3", 300-pound Bob Bitchin with me. We hauled it the rest of the way up, pretty easily with both of us. But I didn't like thinking it could have happened with 100' or more to bring up - without him there to help!

 

[Nomad Willy]

I anchored for years w 13 to 18lb anchors.
I rode out several 50 knot gales on the PNW coast w/o draging and hand hauling or using an electric drum winch or capstan.
My boat was a 30’ Willard.

But to succeed w light anchors you need anchoring experience and a high fluke area is more than just helpful.

Anchor design is more important than weight IMO but it all adds up.

 

[Caballero II]

Hi guys. I have just finished our second season with our new boat the quiet storm. It is 65 loa and 75k.lbs. Running a CQR 105 lb plow. I have full chain with snubbers. I anchor every weekend rain or shine. I am having classic anchor dragging problems in storm conditions. I need to change my anchor to something more reliable. Anchoring is in classic soft mud and crowed anchorages in the north east.

I am a lifetime boater whit tons off anchoring time. Technique is not the issue.

Please can anyone in this size category chime in with what they run. The cqr is rated for the size but just dose not have the holding power I need. . I have never had good luck with the Plow style anchor. I gave this 2 good seasons to try with 6 pull/slides. I also have Fortress fx55 's on board. I keep one rigged in the lazarette for an emergency. They are rated too small for the size boat. Fortress should be a fx85. The fortress website says go up to 2 sizes bigger for storm conditions. This puts me into an fx125. Which is were I think I am going to go.


I ran a fortress fx 55 on my 42 sf 33 k lbs for 15 years. Never had a pull even in 60k storms several time. That anchor was 2 times bigger than what fortress said the normal anchor should be.

Real world recommendations for the size and weight of the style of boat would be appreciated.

I would just go with the new generation anchors. I call them "weighted Picks". Rocna, Utra, etc., they are mentioned above. They seem to dig in better than CQR's or Bruce/Claw type. A Danforth type is always good for sand and mud, but I don't want to deal with one on my foredeck. I might put a Fortress in my bilge for an emergency, but otherwise, I'm not interested.

 

[Meander]

Hi Unicorn here 50,000# 49LOA 180ft all chain 60# CQR - no issues CQR looooves mud - drop and sets 30ft - resets loose 10ft around 180s no issue.

Have not seen thread owner lately - miss a little bit the current flow force vector in this discussion - craziest situations had when wind vector and current flow force vector come from different directions.
Wind force vector is easy to calculate or approximate and any anchor/ground tackle system has a theoretical limit - I placed mine around 1200lbs max holding power in best ground conditions -
wind pushing boat nearly perpendicular to current 2,5kts dont know 900# holding a boat my size in plaze?? - thats when I start praying for wind direction change - drag likely.

a calc for my boat rough guessing windage size and coefficient if hit from bow - I would feel ok till 45kts with my CQR (in east coast mud - sand I dont know honestly) - anything hitting me above I would daisy chain secondary Danforth - scope is king.

windspeed(kt) force(lbs) (warm southern temp)
10 30
15 68
20 121
25 189
30 275
35 371
40 485
45 613
50 757
55 916
60 1090
65 1280
70 1484
75 1703
80 1938
85 2188
90 2453
95 2733

Ya'll have a good one!

 

[J.T kearney]

Hi Unicorn here 50,000# 49LOA 180ft all chain 60# CQR - no issues CQR looooves mud - drop and sets 30ft - resets loose 10ft around 180s no issue.

Have not seen thread owner lately - miss a little bit the current flow force vector in this discussion - craziest situations had when wind vector and current flow force vector come from different directions.
Wind force vector is easy to calculate or approximate and any anchor/ground tackle system has a theoretical limit - I placed mine around 1200lbs max holding power in best ground conditions -
wind pushing boat nearly perpendicular to current 2,5kts dont know 900# holding a boat my size in plaze?? - thats when I start praying for wind direction change - drag likely.

a calc for my boat rough guessing windage size and coefficient if hit from bow - I would feel ok till 45kts with my CQR (in east coast mud - sand I dont know honestly) - anything hitting me above I would daisy chain secondary Danforth - scope is king.

windspeed(kt) force(lbs) (warm southern temp)
10 30
15 68
20 121
25 189
30 275
35 371
40 485
45 613
50 757
55 916
60 1090
65 1280
70 1484
75 1703
80 1938
85 2188
90 2453
95 2733

Ya'll have a good one!

Hi all
Finally returning to the thread, sorry for the delay. Decided to go with vulcan 25 kg , 100 ft 5/16 g4 chain and 250 ft of 5/8 3 strand. know just looking for the correct swivel. Thanks again everyone for your suggestions Cheers J.T.

 

[Greg QS]

Yes its gone now. 103 lb paper weight. Pulled out 500' of chain. Painted every 100' and 20' increments. Made sure it was attached in the boat. Install a new fortress anchor, fx 125 the largest they make. 99% of the northeast is sand or mud. Ill report back after firs storm.

 

[Mac2]

Hi all
Finally returning to the thread, sorry for the delay. Decided to go with vulcan 25 kg , 100 ft 5/16 g4 chain and 250 ft of 5/8 3 strand. know just looking for the correct swivel. Thanks again everyone for your suggestions Cheers J.T.

I would just go with a Crosby shackle. Curious why you went with rope instead of all chain (abrasion, short scope etc.).

 

[firehoser75]

I would avoid a swivel myself. Never had a real problem with bad "twist", and many swivels can actually turn out to be the weakest "link" in the entire system especially since most are not designed to withstand a "side load", which can happen. There have been several reports of boats being lost or badly damaged as a result of swivel failure.
Like Mac2, I would have gone mostly chain (250 feet with 100 feet of rope) so that for most anchorages, I would have been on 100% chain (except when anchoring in fairly deep water).
Just my thoughts, enjoy and have many good sleeps while anchored safely!

 

[Mac2]

I would avoid a swivel myself. Never had a real problem with bad "twist", and many swivels can actually turn out to be the weakest "link" in the entire system especially since most are not designed to withstand a "side load", which can happen. There have been several reports of boats being lost or badly damaged as a result of swivel failure.
Like Mac2, I would have gone mostly chain (250 feet with 100 feet of rope) so that for most anchorages, I would have been on 100% chain (except when anchoring in fairly deep water).
Just my thoughts, enjoy and have many good sleeps while anchored safely!

After dragging when I first started boating ( had my head shoved way way up my ass), I scuba dived on my set anchor in west sound Orcas Island. I was shocked at how many car sized rocks my rode was weaving through. Promptly purchased 320 feet of BBB.

 

[Mambo42]

Hi Unicorn here 50,000# 49LOA 180ft all chain 60# CQR - no issues CQR looooves mud - drop and sets 30ft - resets loose 10ft around 180s no issue.

Have not seen thread owner lately - miss a little bit the current flow force vector in this discussion - craziest situations had when wind vector and current flow force vector come from different directions.
Wind force vector is easy to calculate or approximate and any anchor/ground tackle system has a theoretical limit - I placed mine around 1200lbs max holding power in best ground conditions -
wind pushing boat nearly perpendicular to current 2,5kts dont know 900# holding a boat my size in plaze?? - thats when I start praying for wind direction change - drag likely.

a calc for my boat rough guessing windage size and coefficient if hit from bow - I would feel ok till 45kts with my CQR (in east coast mud - sand I dont know honestly) - anything hitting me above I would daisy chain secondary Danforth - scope is king.

windspeed(kt) force(lbs) (warm southern temp)
10 30
15 68
20 121
25 189
30 275
35 371
40 485
45 613
50 757
55 916
60 1090
65 1280
70 1484
75 1703
80 1938
85 2188
90 2453
95 2733

Ya'll have a good one!

For anyone wanting to make the calculation for their own boat herewith some additional figures.
Windspeed it usually calculated at 10 mtr above the surface, but our boats are usually between 2.5 and 5 mtrs off the sea level. Therefore you can deduct a bit to get to real wind speed on your boat. At 2.5 mtr that would be 70 % of the wind speed, for 5 mtr that would be 80 %.
However, if you want to calculate with the complete wind speed that is also fine.
At 4 Bft: 70 % of 14 kts = 9.8 kts
At 5 Bft: 70 % of 19 kts = 13.3 kts
At 6 Bft: 70 % of 25 kts = 17.5 kts
At 7 Bft: 70 % of 31 kts = 21.7 kts
At 8 Bft: 70 % of 37 kts = 25.9 kts
At 9 Bft: 70 % of 45 kts = 31.5 kts
At 10 Bft: 70 % of 52 kts = 36.4 kts

In order to calculate the forces on your hull (the part that is full in the wind) you can use the following figures:
Then calculate the total frontal surface of your boat and for my boat that is about 19 sqm.

Bft N/m2 kp/m2 N Kp
4 15 1.5 285 28.5
5 26 2.6 494 49.4
6 49 4.9 931 93.1
7 79 7.5 1501 150.1
8 106 10.6 2014 201.4
9 157 15.7 2983 298.3
10 204 20.4 3876 387.6

In other words, you can calculate the total force that the wind can put on your boat. As long as the holding power of your anchor plus chain is more than this wind force, you will not drag.
However, dragging is also a result of the angle of the shank with the sea bed. The maximum holding power of the anchor is at 0 degrees between shank and sea bed.
But at only 5 degrees angle you will no longer have 100 % holding power, you will only have 85 %.
At 10 degrees it is already down to 70 %
At 15 degrees it is 60 %
At 20 degrees it is 50 %
At 25 degrees anchor has lost all holding power.

So even if your maximum holding power is e.g. 2000 N and the total wind force is only 285 N, when the angle of the shank gets up to 25 degrees you won't have any holding power at all and you will drag, no matter what. Which means it is imperative to keep that angle at 0 degrees at all time, which means the chain needs to provide the holding power at the given wind speed.

As I have stated in another topic on anchoring, I let my chain to 90 % of the work, which means if I need a holding power of 1500 N I will drop at least that amount in anchor chain (and most of the time much more). It is the approach the large cargo ships use as well, they rely basically on the chain and not so much on the anchor itself.
Since I have taken that approach I have never dragged an anchor and before I applied this approach we have dragged a few times. In my opinion that was mostly because I did not understand the mathematics behind anchoring. Since I read this book I do understand the mathematics and it makes perfectly sense.

Now, where we are there is no current, so I don't have to calculate for that. But if you have to deal with current and wind it becomes a different story. If anyone is interested I can post those calculations as well and if anyone is interested in the book, it is called: Das ist Motorboot fahren, written by Joachim Schult. It is in German, but nowadays Google translate can solve a lot of language problems for those who don't speak or read German.

 

[J.T kearney]

I would just go with a Crosby shackle. Curious why you went with rope instead of all chain (abrasion, short scope etc.).

I originally had 200 ft. of chain but it was really rusted after 20 years, it looked like they started with non galvanized chain and I had 100 ft. of new G4 5/16 galvanized for our old boat I never installed. Went to look for options to get back to 200 ft. of chain and the price per ft. had tripled and it was 100 bucks to weld a link to combine 2 100 ft. lengths. I'd love to have 200 ft. of chain and sleep a lot better on the hook but for know its 20 ft of water and 4 to 1 will keep me on all chain.
any ideas?
Cheers J.T.

 

[Mac2]

I originally had 200 ft. of chain but it was really rusted after 20 years, it looked like they started with non galvanized chain and I had 100 ft. of new G4 5/16 galvanized for our old boat I never installed. Went to look for options to get back to 200 ft. of chain and the price per ft. had tripled and it was 100 bucks to weld a link to combine 2 100 ft. lengths. I'd love to have 200 ft. of chain and sleep a lot better on the hook but for know its 20 ft of water and 4 to 1 will keep me on all chain.
any ideas?
Cheers J.T.

Good choice on going up to the 25 kg. Not sure where you boat (depth and substrate), but I would work towards an all chain rode for at least a 7 to 1. When the storm comes, it makes a huge difference when you can let more chain out (strength, drag factor for slowing the swing, more weight for angles of rode to anchor, etc.). Also, mostly for me, peace of mind.

 

[Greg QS]

An interesting spring early summer.
Test on the anchor. I have been stuck in 2 storms not. First time 43k overnight and did not budge. Not a whisper of a drag at the same place I slid with the cqr in 30 k winds. . Mud bottom

Second was on a return trip. Wind blew up to 48 knts. I was sitting at the mouth of the marina ad said not a good idea to try to dock in these conditions. I tucked behind land and dropped. Instant hookup in sand . Waited 3 hours for for things to calm down. I think i made the right choice.

Accidental anchor test.
I was putting out the anchor set 5 to one scop and had backed down on the anchor to set. (Fyi this is my first boat with electronic gears) Went out on the bow and realized i was moving apparently I was in gear. I rushed back to the helm and realized I was in forward gear and pulled it out of gear. The chain was tightening and I was worried about reversing and getting chain in my running gear so I did not. I had no time left to loosen the capstan, 70000lbs jerked on the windlass and let a little chain out. Thank god i did not rip the windlass out of the deck or rip off the bow pulpit. The chain left a decent chip in the gelcoat on the bow. I was in 30k winds and let the boat settle back on the anchor. No chain in the gear. But the anchor held. 100% reversal. No damage to the anchor either.

Lesson learned. Leave your windlass clutch a little loose don't clamp it down. You never know what stupid thing can happen. The fact it was a little loose saved damaging the hardware and deck.

 

[Mac2]

I had a similar experience-leaving boat in gear with new to me electronic gears. I was docking boat by myself in a 20 knot wind. After getting a mid line on I realized the boat was still trying to go forward. Quick scramble to the helm and a new pair of underwear solved my problems.
What anchor are you using?